repo_name string | dataset string | owner string | lang string | func_name string | code string | docstring string | url string | sha string |
|---|---|---|---|---|---|---|---|---|
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | SSL_CTX_use_certificate_chain_file | int SSL_CTX_use_certificate_chain_file(SSL_CTX *ctx, const char *file)
{
BIO *in;
int ret=0;
X509 *x=NULL;
ERR_clear_error(); /* clear error stack for SSL_CTX_use_certificate() */
in=BIO_new(BIO_s_file_internal());
if (in == NULL)
{
SSLerr(SSL_F_SSL_CTX_USE_CERTIFICATE_CHAIN_FILE,ERR_R_BUF_LIB);
goto end;
}
if (BIO_read_filename(in,file) <= 0)
{
SSLerr(SSL_F_SSL_CTX_USE_CERTIFICATE_CHAIN_FILE,ERR_R_SYS_LIB);
goto end;
}
x=PEM_read_bio_X509(in,NULL,ctx->default_passwd_callback,ctx->default_passwd_callback_userdata);
if (x == NULL)
{
SSLerr(SSL_F_SSL_CTX_USE_CERTIFICATE_CHAIN_FILE,ERR_R_PEM_LIB);
goto end;
}
ret=SSL_CTX_use_certificate(ctx,x);
if (ERR_peek_error() != 0)
ret = 0; /* Key/certificate mismatch doesn't imply ret==0 ... */
if (ret)
{
/* If we could set up our certificate, now proceed to
* the CA certificates.
*/
X509 *ca;
int r;
unsigned long err;
if (ctx->extra_certs != NULL)
{
sk_X509_pop_free(ctx->extra_certs, X509_free);
ctx->extra_certs = NULL;
}
while ((ca = PEM_read_bio_X509(in,NULL,ctx->default_passwd_callback,ctx->default_passwd_callback_userdata))
!= NULL)
{
r = SSL_CTX_add_extra_chain_cert(ctx, ca);
if (!r)
{
X509_free(ca);
ret = 0;
goto end;
}
/* Note that we must not free r if it was successfully
* added to the chain (while we must free the main
* certificate, since its reference count is increased
* by SSL_CTX_use_certificate). */
}
/* When the while loop ends, it's usually just EOF. */
err = ERR_peek_last_error();
if (ERR_GET_LIB(err) == ERR_LIB_PEM && ERR_GET_REASON(err) == PEM_R_NO_START_LINE)
ERR_clear_error();
else
ret = 0; /* some real error */
}
end:
if (x != NULL) X509_free(x);
if (in != NULL) BIO_free(in);
return(ret);
} | /* Read a file that contains our certificate in "PEM" format,
* possibly followed by a sequence of CA certificates that should be
* sent to the peer in the Certificate message.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/openssl_android/ssl/ssl_rsa.c#L705-L778 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | get | static int get ( io_channel chan, char *buffer, int maxlen, int *length )
{
int status;
struct io_status iosb;
status = SYS$QIOW ( 0, chan, IO$_READVBLK, &iosb, 0, 0,
buffer, maxlen, 0, 0, 0, 0 );
if ( (status&1) == 1 ) status = iosb.status;
if ( (status&1) == 1 ) *length = iosb.count;
return status;
} | /*****************************************************************************/
/* Decnet I/O routines.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/openssl_android/ssl/ssl_task.c#L167-L176 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | general_request | static int general_request ( io_channel chan, struct rpc_msg *msg, int length )
{
return 48;
} | /***************************************************************************/
/* Handle operations on the 'G' channel.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/openssl_android/ssl/ssl_task.c#L190-L193 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | main | int main ( int argc, char **argv )
{
int status, length;
io_channel chan;
struct rpc_msg msg;
char *CApath=NULL,*CAfile=NULL;
int badop=0;
int ret=1;
int client_auth=0;
int server_auth=0;
SSL_CTX *s_ctx=NULL;
/*
* Confirm logical link with initiating client.
*/
LIB$INIT_TIMER();
status = SYS$ASSIGN ( &sysnet, &chan, 0, 0, 0 );
printf("status of assign to SYS$NET: %d\n", status );
/*
* Initialize standard out and error files.
*/
if (bio_err == NULL)
if ((bio_err=BIO_new(BIO_s_file())) != NULL)
BIO_set_fp(bio_err,stderr,BIO_NOCLOSE);
if (bio_stdout == NULL)
if ((bio_stdout=BIO_new(BIO_s_file())) != NULL)
BIO_set_fp(bio_stdout,stdout,BIO_NOCLOSE);
/*
* get the preferred cipher list and other initialization
*/
if (cipher == NULL) cipher=getenv("SSL_CIPHER");
printf("cipher list: %s\n", cipher ? cipher : "{undefined}" );
SSL_load_error_strings();
OpenSSL_add_all_algorithms();
/* DRM, this was the original, but there is no such thing as SSLv2()
s_ctx=SSL_CTX_new(SSLv2());
*/
s_ctx=SSL_CTX_new(SSLv2_server_method());
if (s_ctx == NULL) goto end;
SSL_CTX_use_certificate_file(s_ctx,TEST_SERVER_CERT,SSL_FILETYPE_PEM);
SSL_CTX_use_RSAPrivateKey_file(s_ctx,TEST_SERVER_CERT,SSL_FILETYPE_PEM);
printf("Loaded server certificate: '%s'\n", TEST_SERVER_CERT );
/*
* Take commands from client until bad status.
*/
LIB$SHOW_TIMER();
status = doit ( chan, s_ctx );
LIB$SHOW_TIMER();
/*
* do final cleanup and exit.
*/
end:
if (s_ctx != NULL) SSL_CTX_free(s_ctx);
LIB$SHOW_TIMER();
return 1;
} | /***************************************************************************/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/openssl_android/ssl/ssl_task.c#L195-L255 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | tls1_process_ticket | int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
const unsigned char *limit, SSL_SESSION **ret)
{
/* Point after session ID in client hello */
const unsigned char *p = session_id + len;
unsigned short i;
if ((s->version <= SSL3_VERSION) || !limit)
return 1;
if (p >= limit)
return -1;
/* Skip past cipher list */
n2s(p, i);
p+= i;
if (p >= limit)
return -1;
/* Skip past compression algorithm list */
i = *(p++);
p += i;
if (p > limit)
return -1;
/* Now at start of extensions */
if ((p + 2) >= limit)
return 1;
n2s(p, i);
while ((p + 4) <= limit)
{
unsigned short type, size;
n2s(p, type);
n2s(p, size);
if (p + size > limit)
return 1;
if (type == TLSEXT_TYPE_session_ticket)
{
/* If tickets disabled indicate cache miss which will
* trigger a full handshake
*/
if (SSL_get_options(s) & SSL_OP_NO_TICKET)
return 0;
/* If zero length not client will accept a ticket
* and indicate cache miss to trigger full handshake
*/
if (size == 0)
{
s->tlsext_ticket_expected = 1;
return 0; /* Cache miss */
}
return tls_decrypt_ticket(s, p, size, session_id, len,
ret);
}
p += size;
}
return 1;
} | /* Since the server cache lookup is done early on in the processing of client
* hello and other operations depend on the result we need to handle any TLS
* session ticket extension at the same time.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/openssl_android/ssl/t1_lib.c#L731-L783 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | write_png | void write_png(char *file_name /* , ... other image information ... */)
{
FILE *fp;
png_structp png_ptr;
png_infop info_ptr;
png_colorp palette;
/* Open the file */
fp = fopen(file_name, "wb");
if (fp == NULL)
return (ERROR);
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also check that
* the library version is compatible with the one used at compile time,
* in case we are using dynamically linked libraries. REQUIRED.
*/
png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
png_voidp user_error_ptr, user_error_fn, user_warning_fn);
if (png_ptr == NULL)
{
fclose(fp);
return (ERROR);
}
/* Allocate/initialize the image information data. REQUIRED */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL)
{
fclose(fp);
png_destroy_write_struct(&png_ptr, NULL);
return (ERROR);
}
/* Set error handling. REQUIRED if you aren't supplying your own
* error handling functions in the png_create_write_struct() call.
*/
if (setjmp(png_jmpbuf(png_ptr)))
{
/* If we get here, we had a problem writing the file */
fclose(fp);
png_destroy_write_struct(&png_ptr, &info_ptr);
return (ERROR);
}
/* One of the following I/O initialization functions is REQUIRED */
#ifdef streams /* I/O initialization method 1 */
/* Set up the output control if you are using standard C streams */
png_init_io(png_ptr, fp);
#else no_streams /* I/O initialization method 2 */
/* If you are using replacement write functions, instead of calling
* png_init_io() here you would call
*/
png_set_write_fn(png_ptr, (void *)user_io_ptr, user_write_fn,
user_IO_flush_function);
/* where user_io_ptr is a structure you want available to the callbacks */
#endif no_streams /* Only use one initialization method */
#ifdef hilevel
/* This is the easy way. Use it if you already have all the
* image info living in the structure. You could "|" many
* PNG_TRANSFORM flags into the png_transforms integer here.
*/
png_write_png(png_ptr, info_ptr, png_transforms, NULL);
#else
/* This is the hard way */
/* Set the image information here. Width and height are up to 2^31,
* bit_depth is one of 1, 2, 4, 8, or 16, but valid values also depend on
* the color_type selected. color_type is one of PNG_COLOR_TYPE_GRAY,
* PNG_COLOR_TYPE_GRAY_ALPHA, PNG_COLOR_TYPE_PALETTE, PNG_COLOR_TYPE_RGB,
* or PNG_COLOR_TYPE_RGB_ALPHA. interlace is either PNG_INTERLACE_NONE or
* PNG_INTERLACE_ADAM7, and the compression_type and filter_type MUST
* currently be PNG_COMPRESSION_TYPE_BASE and PNG_FILTER_TYPE_BASE. REQUIRED
*/
png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, PNG_COLOR_TYPE_???,
PNG_INTERLACE_????, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
/* Set the palette if there is one. REQUIRED for indexed-color images */
palette = (png_colorp)png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH
* (sizeof (png_color)));
/* ... Set palette colors ... */
png_set_PLTE(png_ptr, info_ptr, palette, PNG_MAX_PALETTE_LENGTH);
/* You must not free palette here, because png_set_PLTE only makes a link to
* the palette that you malloced. Wait until you are about to destroy
* the png structure.
*/
/* Optional significant bit (sBIT) chunk */
png_color_8 sig_bit;
/* If we are dealing with a grayscale image then */
sig_bit.gray = true_bit_depth;
/* Otherwise, if we are dealing with a color image then */
sig_bit.red = true_red_bit_depth;
sig_bit.green = true_green_bit_depth;
sig_bit.blue = true_blue_bit_depth;
/* If the image has an alpha channel then */
sig_bit.alpha = true_alpha_bit_depth;
png_set_sBIT(png_ptr, info_ptr, &sig_bit);
/* Optional gamma chunk is strongly suggested if you have any guess
* as to the correct gamma of the image.
*/
png_set_gAMA(png_ptr, info_ptr, gamma);
/* Optionally write comments into the image */
{
png_text text_ptr[3];
char key0[]="Title";
char text0[]="Mona Lisa";
text_ptr[0].key = key0;
text_ptr[0].text = text0;
text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[0].itxt_length = 0;
text_ptr[0].lang = NULL;
text_ptr[0].lang_key = NULL;
char key1[]="Author";
char text1[]="Leonardo DaVinci";
text_ptr[1].key = key1;
text_ptr[1].text = text1;
text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[1].itxt_length = 0;
text_ptr[1].lang = NULL;
text_ptr[1].lang_key = NULL;
char key2[]="Description";
char text2[]="<long text>";
text_ptr[2].key = key2;
text_ptr[2].text = text2;
text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
text_ptr[2].itxt_length = 0;
text_ptr[2].lang = NULL;
text_ptr[2].lang_key = NULL;
png_set_text(write_ptr, write_info_ptr, text_ptr, 3);
}
/* Other optional chunks like cHRM, bKGD, tRNS, tIME, oFFs, pHYs */
/* Note that if sRGB is present the gAMA and cHRM chunks must be ignored
* on read and, if your application chooses to write them, they must
* be written in accordance with the sRGB profile
*/
/* Write the file header information. REQUIRED */
png_write_info(png_ptr, info_ptr);
/* If you want, you can write the info in two steps, in case you need to
* write your private chunk ahead of PLTE:
*
* png_write_info_before_PLTE(write_ptr, write_info_ptr);
* write_my_chunk();
* png_write_info(png_ptr, info_ptr);
*
* However, given the level of known- and unknown-chunk support in 1.2.0
* and up, this should no longer be necessary.
*/
/* Once we write out the header, the compression type on the text
* chunks gets changed to PNG_TEXT_COMPRESSION_NONE_WR or
* PNG_TEXT_COMPRESSION_zTXt_WR, so it doesn't get written out again
* at the end.
*/
/* Set up the transformations you want. Note that these are
* all optional. Only call them if you want them.
*/
/* Invert monochrome pixels */
png_set_invert_mono(png_ptr);
/* Shift the pixels up to a legal bit depth and fill in
* as appropriate to correctly scale the image.
*/
png_set_shift(png_ptr, &sig_bit);
/* Pack pixels into bytes */
png_set_packing(png_ptr);
/* Swap location of alpha bytes from ARGB to RGBA */
png_set_swap_alpha(png_ptr);
/* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
* RGB (4 channels -> 3 channels). The second parameter is not used.
*/
png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
/* Flip BGR pixels to RGB */
png_set_bgr(png_ptr);
/* Swap bytes of 16-bit files to most significant byte first */
png_set_swap(png_ptr);
/* Swap bits of 1, 2, 4 bit packed pixel formats */
png_set_packswap(png_ptr);
/* Turn on interlace handling if you are not using png_write_image() */
if (interlacing)
number_passes = png_set_interlace_handling(png_ptr);
else
number_passes = 1;
/* The easiest way to write the image (you may have a different memory
* layout, however, so choose what fits your needs best). You need to
* use the first method if you aren't handling interlacing yourself.
*/
png_uint_32 k, height, width;
/* In this example, "image" is a one-dimensional array of bytes */
png_byte image[height*width*bytes_per_pixel];
png_bytep row_pointers[height];
if (height > PNG_UINT_32_MAX/(sizeof (png_bytep)))
png_error (png_ptr, "Image is too tall to process in memory");
/* Set up pointers into your "image" byte array */
for (k = 0; k < height; k++)
row_pointers[k] = image + k*width*bytes_per_pixel;
/* One of the following output methods is REQUIRED */
#ifdef entire /* Write out the entire image data in one call */
png_write_image(png_ptr, row_pointers);
/* The other way to write the image - deal with interlacing */
#else no_entire /* Write out the image data by one or more scanlines */
/* The number of passes is either 1 for non-interlaced images,
* or 7 for interlaced images.
*/
for (pass = 0; pass < number_passes; pass++)
{
/* Write a few rows at a time. */
png_write_rows(png_ptr, &row_pointers[first_row], number_of_rows);
/* If you are only writing one row at a time, this works */
for (y = 0; y < height; y++)
png_write_rows(png_ptr, &row_pointers[y], 1);
}
#endif no_entire /* Use only one output method */
/* You can write optional chunks like tEXt, zTXt, and tIME at the end
* as well. Shouldn't be necessary in 1.2.0 and up as all the public
* chunks are supported and you can use png_set_unknown_chunks() to
* register unknown chunks into the info structure to be written out.
*/
/* It is REQUIRED to call this to finish writing the rest of the file */
png_write_end(png_ptr, info_ptr);
#endif hilevel
/* If you png_malloced a palette, free it here (don't free info_ptr->palette,
* as recommended in versions 1.0.5m and earlier of this example; if
* libpng mallocs info_ptr->palette, libpng will free it). If you
* allocated it with malloc() instead of png_malloc(), use free() instead
* of png_free().
*/
png_free(png_ptr, palette);
palette = NULL;
/* Similarly, if you png_malloced any data that you passed in with
* png_set_something(), such as a hist or trans array, free it here,
* when you can be sure that libpng is through with it.
*/
png_free(png_ptr, trans);
trans = NULL;
/* Whenever you use png_free() it is a good idea to set the pointer to
* NULL in case your application inadvertently tries to png_free() it
* again. When png_free() sees a NULL it returns without action, thus
* avoiding the double-free security problem.
*/
/* Clean up after the write, and free any memory allocated */
png_destroy_write_struct(&png_ptr, &info_ptr);
/* Close the file */
fclose(fp);
/* That's it */
return (OK);
} | /* Write a png file */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/example.c#L764-L1059 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_sig_cmp | int PNGAPI
png_sig_cmp(png_const_bytep sig, png_size_t start, png_size_t num_to_check)
{
png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
if (num_to_check > 8)
num_to_check = 8;
else if (num_to_check < 1)
return (-1);
if (start > 7)
return (-1);
if (start + num_to_check > 8)
num_to_check = 8 - start;
return ((int)(memcmp(&sig[start], &png_signature[start], num_to_check)));
} | /* Checks whether the supplied bytes match the PNG signature. We allow
* checking less than the full 8-byte signature so that those apps that
* already read the first few bytes of a file to determine the file type
* can simply check the remaining bytes for extra assurance. Returns
* an integer less than, equal to, or greater than zero if sig is found,
* respectively, to be less than, to match, or be greater than the correct
* PNG signature (this is the same behavior as strcmp, memcmp, etc).
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L48-L66 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_destroy_info_struct | void PNGAPI
png_destroy_info_struct(png_const_structrp png_ptr, png_infopp info_ptr_ptr)
{
png_inforp info_ptr = NULL;
png_debug(1, "in png_destroy_info_struct");
if (png_ptr == NULL)
return;
if (info_ptr_ptr != NULL)
info_ptr = *info_ptr_ptr;
if (info_ptr != NULL)
{
/* Do this first in case of an error below; if the app implements its own
* memory management this can lead to png_free calling png_error, which
* will abort this routine and return control to the app error handler.
* An infinite loop may result if it then tries to free the same info
* ptr.
*/
*info_ptr_ptr = NULL;
png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
memset(info_ptr, 0, (sizeof *info_ptr));
png_free(png_ptr, info_ptr);
}
} | /* This function frees the memory associated with a single info struct.
* Normally, one would use either png_destroy_read_struct() or
* png_destroy_write_struct() to free an info struct, but this may be
* useful for some applications. From libpng 1.6.0 this function is also used
* internally to implement the png_info release part of the 'struct' destroy
* APIs. This ensures that all possible approaches free the same data (all of
* it).
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L361-L388 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_data_freer | void PNGAPI
png_data_freer(png_const_structrp png_ptr, png_inforp info_ptr,
int freer, png_uint_32 mask)
{
png_debug(1, "in png_data_freer");
if (png_ptr == NULL || info_ptr == NULL)
return;
if (freer == PNG_DESTROY_WILL_FREE_DATA)
info_ptr->free_me |= mask;
else if (freer == PNG_USER_WILL_FREE_DATA)
info_ptr->free_me &= ~mask;
else
png_error(png_ptr, "Unknown freer parameter in png_data_freer");
} | /* The following API is not called internally */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L425-L442 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_init_io | void PNGAPI
png_init_io(png_structrp png_ptr, png_FILE_p fp)
{
png_debug(1, "in png_init_io");
if (png_ptr == NULL)
return;
png_ptr->io_ptr = (png_voidp)fp;
} | /* Initialize the default input/output functions for the PNG file. If you
* use your own read or write routines, you can call either png_set_read_fn()
* or png_set_write_fn() instead of png_init_io(). If you have defined
* PNG_NO_STDIO or otherwise disabled PNG_STDIO_SUPPORTED, you must use a
* function of your own because "FILE *" isn't necessarily available.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L662-L671 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_save_int_32 | void PNGAPI
png_save_int_32(png_bytep buf, png_int_32 i)
{
buf[0] = (png_byte)((i >> 24) & 0xff);
buf[1] = (png_byte)((i >> 16) & 0xff);
buf[2] = (png_byte)((i >> 8) & 0xff);
buf[3] = (png_byte)(i & 0xff);
} | /* The png_save_int_32 function assumes integers are stored in two's
* complement format. If this isn't the case, then this routine needs to
* be modified to write data in two's complement format. Note that,
* the following works correctly even if png_int_32 has more than 32 bits
* (compare the more complex code required on read for sign extension.)
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L681-L688 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_convert_to_rfc1123_buffer | int PNGAPI
png_convert_to_rfc1123_buffer(char out[29], png_const_timep ptime)
{
static PNG_CONST char short_months[12][4] =
{"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
if (out == NULL)
return 0;
if (ptime->year > 9999 /* RFC1123 limitation */ ||
ptime->month == 0 || ptime->month > 12 ||
ptime->day == 0 || ptime->day > 31 ||
ptime->hour > 23 || ptime->minute > 59 ||
ptime->second > 60)
return 0;
{
size_t pos = 0;
char number_buf[5]; /* enough for a four-digit year */
# define APPEND_STRING(string) pos = png_safecat(out, 29, pos, (string))
# define APPEND_NUMBER(format, value)\
APPEND_STRING(PNG_FORMAT_NUMBER(number_buf, format, (value)))
# define APPEND(ch) if (pos < 28) out[pos++] = (ch)
APPEND_NUMBER(PNG_NUMBER_FORMAT_u, (unsigned)ptime->day);
APPEND(' ');
APPEND_STRING(short_months[(ptime->month - 1)]);
APPEND(' ');
APPEND_NUMBER(PNG_NUMBER_FORMAT_u, ptime->year);
APPEND(' ');
APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->hour);
APPEND(':');
APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->minute);
APPEND(':');
APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->second);
APPEND_STRING(" +0000"); /* This reliably terminates the buffer */
# undef APPEND
# undef APPEND_NUMBER
# undef APPEND_STRING
}
return 1;
} | /* Convert the supplied time into an RFC 1123 string suitable for use in
* a "Creation Time" or other text-based time string.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L695-L740 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_convert_to_rfc1123 | png_const_charp PNGAPI
png_convert_to_rfc1123(png_structrp png_ptr, png_const_timep ptime)
{
if (png_ptr != NULL)
{
/* The only failure above if png_ptr != NULL is from an invalid ptime */
if (!png_convert_to_rfc1123_buffer(png_ptr->time_buffer, ptime))
png_warning(png_ptr, "Ignoring invalid time value");
else
return png_ptr->time_buffer;
}
return NULL;
} | /* To do: remove the following from libpng-1.7 */
/* Original API that uses a private buffer in png_struct.
* Deprecated because it causes png_struct to carry a spurious temporary
* buffer (png_struct::time_buffer), better to have the caller pass this in.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L748-L762 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_reset_zstream | int PNGAPI
png_reset_zstream(png_structrp png_ptr)
{
if (png_ptr == NULL)
return Z_STREAM_ERROR;
/* WARNING: this resets the window bits to the maximum! */
return (inflateReset(&png_ptr->zstream));
} | /* This function, added to libpng-1.0.6g, is untested. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L878-L886 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_colorspace_check_gamma | static int
png_colorspace_check_gamma(png_const_structrp png_ptr,
png_colorspacerp colorspace, png_fixed_point gAMA, int from)
/* This is called to check a new gamma value against an existing one. The
* routine returns false if the new gamma value should not be written.
*
* 'from' says where the new gamma value comes from:
*
* 0: the new gamma value is the libpng estimate for an ICC profile
* 1: the new gamma value comes from a gAMA chunk
* 2: the new gamma value comes from an sRGB chunk
*/
{
png_fixed_point gtest;
if ((colorspace->flags & PNG_COLORSPACE_HAVE_GAMMA) != 0 &&
(!png_muldiv(>est, colorspace->gamma, PNG_FP_1, gAMA) ||
png_gamma_significant(gtest)))
{
/* Either this is an sRGB image, in which case the calculated gamma
* approximation should match, or this is an image with a profile and the
* value libpng calculates for the gamma of the profile does not match the
* value recorded in the file. The former, sRGB, case is an error, the
* latter is just a warning.
*/
if ((colorspace->flags & PNG_COLORSPACE_FROM_sRGB) != 0 || from == 2)
{
png_chunk_report(png_ptr, "gamma value does not match sRGB",
PNG_CHUNK_ERROR);
/* Do not overwrite an sRGB value */
return from == 2;
}
else /* sRGB tag not involved */
{
png_chunk_report(png_ptr, "gamma value does not match libpng estimate",
PNG_CHUNK_WARNING);
return from == 1;
}
}
return 1;
} | /* always set if COLORSPACE */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L976-L1018 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | if | else if (colorspace->flags & PNG_COLORSPACE_INVALID)
return;
else
{
if (png_colorspace_check_gamma(png_ptr, colorspace, gAMA, 1/*from gAMA*/))
{
/* Store this gamma value. */
colorspace->gamma = gAMA;
colorspace->flags |=
(PNG_COLORSPACE_HAVE_GAMMA | PNG_COLORSPACE_FROM_gAMA);
}
/* At present if the check_gamma test fails the gamma of the colorspace is
* not updated however the colorspace is not invalidated. This
* corresponds to the case where the existing gamma comes from an sRGB
* chunk or profile. An error message has already been output.
*/
return;
} | /* Do nothing if the colorspace is already invalid */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L1048-L1067 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_xy_from_XYZ | static int
png_xy_from_XYZ(png_xy *xy, const png_XYZ *XYZ)
{
png_int_32 d, dwhite, whiteX, whiteY;
d = XYZ->red_X + XYZ->red_Y + XYZ->red_Z;
if (!png_muldiv(&xy->redx, XYZ->red_X, PNG_FP_1, d)) return 1;
if (!png_muldiv(&xy->redy, XYZ->red_Y, PNG_FP_1, d)) return 1;
dwhite = d;
whiteX = XYZ->red_X;
whiteY = XYZ->red_Y;
d = XYZ->green_X + XYZ->green_Y + XYZ->green_Z;
if (!png_muldiv(&xy->greenx, XYZ->green_X, PNG_FP_1, d)) return 1;
if (!png_muldiv(&xy->greeny, XYZ->green_Y, PNG_FP_1, d)) return 1;
dwhite += d;
whiteX += XYZ->green_X;
whiteY += XYZ->green_Y;
d = XYZ->blue_X + XYZ->blue_Y + XYZ->blue_Z;
if (!png_muldiv(&xy->bluex, XYZ->blue_X, PNG_FP_1, d)) return 1;
if (!png_muldiv(&xy->bluey, XYZ->blue_Y, PNG_FP_1, d)) return 1;
dwhite += d;
whiteX += XYZ->blue_X;
whiteY += XYZ->blue_Y;
/* The reference white is simply the sum of the end-point (X,Y,Z) vectors,
* thus:
*/
if (!png_muldiv(&xy->whitex, whiteX, PNG_FP_1, dwhite)) return 1;
if (!png_muldiv(&xy->whitey, whiteY, PNG_FP_1, dwhite)) return 1;
return 0;
} | /* Added at libpng-1.5.5 to support read and write of true CIEXYZ values for
* cHRM, as opposed to using chromaticities. These internal APIs return
* non-zero on a parameter error. The X, Y and Z values are required to be
* positive and less than 1.0.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L1138-L1171 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_colorspace_check_xy | static int
png_colorspace_check_xy(png_XYZ *XYZ, const png_xy *xy)
{
int result;
png_xy xy_test;
/* As a side-effect this routine also returns the XYZ endpoints. */
result = png_XYZ_from_xy(XYZ, xy);
if (result) return result;
result = png_xy_from_XYZ(&xy_test, XYZ);
if (result) return result;
if (png_colorspace_endpoints_match(xy, &xy_test,
5/*actually, the math is pretty accurate*/))
return 0;
/* Too much slip */
return 1;
} | /* Added in libpng-1.6.0, a different check for the validity of a set of cHRM
* chunk chromaticities. Earlier checks used to simply look for the overflow
* condition (where the determinant of the matrix to solve for XYZ ends up zero
* because the chromaticity values are not all distinct.) Despite this it is
* theoretically possible to produce chromaticities that are apparently valid
* but that rapidly degrade to invalid, potentially crashing, sets because of
* arithmetic inaccuracies when calculations are performed on them. The new
* check is to round-trip xy -> XYZ -> xy and then check that the result is
* within a small percentage of the original.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L1496-L1515 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_colorspace_check_XYZ | static int
png_colorspace_check_XYZ(png_xy *xy, png_XYZ *XYZ)
{
int result;
png_XYZ XYZtemp;
result = png_XYZ_normalize(XYZ);
if (result) return result;
result = png_xy_from_XYZ(xy, XYZ);
if (result) return result;
XYZtemp = *XYZ;
return png_colorspace_check_xy(&XYZtemp, xy);
} | /* This is the check going the other way. The XYZ is modified to normalize it
* (another side-effect) and the xy chromaticities are returned.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L1520-L1534 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_icc_tag_char | static char
png_icc_tag_char(png_uint_32 byte)
{
byte &= 0xff;
if (byte >= 32 && byte <= 126)
return (char)byte;
else
return '?';
} | /* Error message generation */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L1660-L1668 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_colorspace_set_ICC | int /* PRIVATE */
png_colorspace_set_ICC(png_const_structrp png_ptr, png_colorspacerp colorspace,
png_const_charp name, png_uint_32 profile_length, png_const_bytep profile,
int color_type)
{
if (colorspace->flags & PNG_COLORSPACE_INVALID)
return 0;
if (png_icc_check_length(png_ptr, colorspace, name, profile_length) &&
png_icc_check_header(png_ptr, colorspace, name, profile_length, profile,
color_type) &&
png_icc_check_tag_table(png_ptr, colorspace, name, profile_length,
profile))
{
# ifdef PNG_sRGB_SUPPORTED
/* If no sRGB support, don't try storing sRGB information */
png_icc_set_sRGB(png_ptr, colorspace, profile, 0);
# endif
return 1;
}
/* Failure case */
return 0;
} | /* PNG_READ_sRGB_SUPPORTED */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L2270-L2293 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_check_fp_string | int
png_check_fp_string(png_const_charp string, png_size_t size)
{
int state=0;
png_size_t char_index=0;
if (png_check_fp_number(string, size, &state, &char_index) &&
(char_index == size || string[char_index] == 0))
return state /* must be non-zero - see above */;
return 0; /* i.e. fail */
} | /* The same but for a complete string. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L2643-L2654 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_pow10 | static double
png_pow10(int power)
{
int recip = 0;
double d = 1;
/* Handle negative exponent with a reciprocal at the end because
* 10 is exact whereas .1 is inexact in base 2
*/
if (power < 0)
{
if (power < DBL_MIN_10_EXP) return 0;
recip = 1, power = -power;
}
if (power > 0)
{
/* Decompose power bitwise. */
double mult = 10;
do
{
if (power & 1) d *= mult;
mult *= mult;
power >>= 1;
}
while (power > 0);
if (recip) d = 1/d;
}
/* else power is 0 and d is 1 */
return d;
} | /* Utility used below - a simple accurate power of ten from an integral
* exponent.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L2662-L2694 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_ascii_from_fp | void /* PRIVATE */
png_ascii_from_fp(png_const_structrp png_ptr, png_charp ascii, png_size_t size,
double fp, unsigned int precision)
{
/* We use standard functions from math.h, but not printf because
* that would require stdio. The caller must supply a buffer of
* sufficient size or we will png_error. The tests on size and
* the space in ascii[] consumed are indicated below.
*/
if (precision < 1)
precision = DBL_DIG;
/* Enforce the limit of the implementation precision too. */
if (precision > DBL_DIG+1)
precision = DBL_DIG+1;
/* Basic sanity checks */
if (size >= precision+5) /* See the requirements below. */
{
if (fp < 0)
{
fp = -fp;
*ascii++ = 45; /* '-' PLUS 1 TOTAL 1 */
--size;
}
if (fp >= DBL_MIN && fp <= DBL_MAX)
{
int exp_b10; /* A base 10 exponent */
double base; /* 10^exp_b10 */
/* First extract a base 10 exponent of the number,
* the calculation below rounds down when converting
* from base 2 to base 10 (multiply by log10(2) -
* 0.3010, but 77/256 is 0.3008, so exp_b10 needs to
* be increased. Note that the arithmetic shift
* performs a floor() unlike C arithmetic - using a
* C multiply would break the following for negative
* exponents.
*/
(void)frexp(fp, &exp_b10); /* exponent to base 2 */
exp_b10 = (exp_b10 * 77) >> 8; /* <= exponent to base 10 */
/* Avoid underflow here. */
base = png_pow10(exp_b10); /* May underflow */
while (base < DBL_MIN || base < fp)
{
/* And this may overflow. */
double test = png_pow10(exp_b10+1);
if (test <= DBL_MAX)
++exp_b10, base = test;
else
break;
}
/* Normalize fp and correct exp_b10, after this fp is in the
* range [.1,1) and exp_b10 is both the exponent and the digit
* *before* which the decimal point should be inserted
* (starting with 0 for the first digit). Note that this
* works even if 10^exp_b10 is out of range because of the
* test on DBL_MAX above.
*/
fp /= base;
while (fp >= 1) fp /= 10, ++exp_b10;
/* Because of the code above fp may, at this point, be
* less than .1, this is ok because the code below can
* handle the leading zeros this generates, so no attempt
* is made to correct that here.
*/
{
int czero, clead, cdigits;
char exponent[10];
/* Allow up to two leading zeros - this will not lengthen
* the number compared to using E-n.
*/
if (exp_b10 < 0 && exp_b10 > -3) /* PLUS 3 TOTAL 4 */
{
czero = -exp_b10; /* PLUS 2 digits: TOTAL 3 */
exp_b10 = 0; /* Dot added below before first output. */
}
else
czero = 0; /* No zeros to add */
/* Generate the digit list, stripping trailing zeros and
* inserting a '.' before a digit if the exponent is 0.
*/
clead = czero; /* Count of leading zeros */
cdigits = 0; /* Count of digits in list. */
do
{
double d;
fp *= 10;
/* Use modf here, not floor and subtract, so that
* the separation is done in one step. At the end
* of the loop don't break the number into parts so
* that the final digit is rounded.
*/
if (cdigits+czero-clead+1 < (int)precision)
fp = modf(fp, &d);
else
{
d = floor(fp + .5);
if (d > 9)
{
/* Rounding up to 10, handle that here. */
if (czero > 0)
{
--czero, d = 1;
if (cdigits == 0) --clead;
}
else
{
while (cdigits > 0 && d > 9)
{
int ch = *--ascii;
if (exp_b10 != (-1))
++exp_b10;
else if (ch == 46)
{
ch = *--ascii, ++size;
/* Advance exp_b10 to '1', so that the
* decimal point happens after the
* previous digit.
*/
exp_b10 = 1;
}
--cdigits;
d = ch - 47; /* I.e. 1+(ch-48) */
}
/* Did we reach the beginning? If so adjust the
* exponent but take into account the leading
* decimal point.
*/
if (d > 9) /* cdigits == 0 */
{
if (exp_b10 == (-1))
{
/* Leading decimal point (plus zeros?), if
* we lose the decimal point here it must
* be reentered below.
*/
int ch = *--ascii;
if (ch == 46)
++size, exp_b10 = 1;
/* Else lost a leading zero, so 'exp_b10' is
* still ok at (-1)
*/
}
else
++exp_b10;
/* In all cases we output a '1' */
d = 1;
}
}
}
fp = 0; /* Guarantees termination below. */
}
if (d == 0)
{
++czero;
if (cdigits == 0) ++clead;
}
else
{
/* Included embedded zeros in the digit count. */
cdigits += czero - clead;
clead = 0;
while (czero > 0)
{
/* exp_b10 == (-1) means we just output the decimal
* place - after the DP don't adjust 'exp_b10' any
* more!
*/
if (exp_b10 != (-1))
{
if (exp_b10 == 0) *ascii++ = 46, --size;
/* PLUS 1: TOTAL 4 */
--exp_b10;
}
*ascii++ = 48, --czero;
}
if (exp_b10 != (-1))
{
if (exp_b10 == 0) *ascii++ = 46, --size; /* counted
above */
--exp_b10;
}
*ascii++ = (char)(48 + (int)d), ++cdigits;
}
}
while (cdigits+czero-clead < (int)precision && fp > DBL_MIN);
/* The total output count (max) is now 4+precision */
/* Check for an exponent, if we don't need one we are
* done and just need to terminate the string. At
* this point exp_b10==(-1) is effectively if flag - it got
* to '-1' because of the decrement after outputing
* the decimal point above (the exponent required is
* *not* -1!)
*/
if (exp_b10 >= (-1) && exp_b10 <= 2)
{
/* The following only happens if we didn't output the
* leading zeros above for negative exponent, so this
* doest add to the digit requirement. Note that the
* two zeros here can only be output if the two leading
* zeros were *not* output, so this doesn't increase
* the output count.
*/
while (--exp_b10 >= 0) *ascii++ = 48;
*ascii = 0;
/* Total buffer requirement (including the '\0') is
* 5+precision - see check at the start.
*/
return;
}
/* Here if an exponent is required, adjust size for
* the digits we output but did not count. The total
* digit output here so far is at most 1+precision - no
* decimal point and no leading or trailing zeros have
* been output.
*/
size -= cdigits;
*ascii++ = 69, --size; /* 'E': PLUS 1 TOTAL 2+precision */
/* The following use of an unsigned temporary avoids ambiguities in
* the signed arithmetic on exp_b10 and permits GCC at least to do
* better optimization.
*/
{
unsigned int uexp_b10;
if (exp_b10 < 0)
{
*ascii++ = 45, --size; /* '-': PLUS 1 TOTAL 3+precision */
uexp_b10 = -exp_b10;
}
else
uexp_b10 = exp_b10;
cdigits = 0;
while (uexp_b10 > 0)
{
exponent[cdigits++] = (char)(48 + uexp_b10 % 10);
uexp_b10 /= 10;
}
}
/* Need another size check here for the exponent digits, so
* this need not be considered above.
*/
if ((int)size > cdigits)
{
while (cdigits > 0) *ascii++ = exponent[--cdigits];
*ascii = 0;
return;
}
}
}
else if (!(fp >= DBL_MIN))
{
*ascii++ = 48; /* '0' */
*ascii = 0;
return;
}
else
{
*ascii++ = 105; /* 'i' */
*ascii++ = 110; /* 'n' */
*ascii++ = 102; /* 'f' */
*ascii = 0;
return;
}
}
/* Here on buffer too small. */
png_error(png_ptr, "ASCII conversion buffer too small");
} | /* Function to format a floating point value in ASCII with a given
* precision.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L2699-L3006 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_ascii_from_fixed | void /* PRIVATE */
png_ascii_from_fixed(png_const_structrp png_ptr, png_charp ascii,
png_size_t size, png_fixed_point fp)
{
/* Require space for 10 decimal digits, a decimal point, a minus sign and a
* trailing \0, 13 characters:
*/
if (size > 12)
{
png_uint_32 num;
/* Avoid overflow here on the minimum integer. */
if (fp < 0)
*ascii++ = 45, --size, num = -fp;
else
num = fp;
if (num <= 0x80000000) /* else overflowed */
{
unsigned int ndigits = 0, first = 16 /* flag value */;
char digits[10];
while (num)
{
/* Split the low digit off num: */
unsigned int tmp = num/10;
num -= tmp*10;
digits[ndigits++] = (char)(48 + num);
/* Record the first non-zero digit, note that this is a number
* starting at 1, it's not actually the array index.
*/
if (first == 16 && num > 0)
first = ndigits;
num = tmp;
}
if (ndigits > 0)
{
while (ndigits > 5) *ascii++ = digits[--ndigits];
/* The remaining digits are fractional digits, ndigits is '5' or
* smaller at this point. It is certainly not zero. Check for a
* non-zero fractional digit:
*/
if (first <= 5)
{
unsigned int i;
*ascii++ = 46; /* decimal point */
/* ndigits may be <5 for small numbers, output leading zeros
* then ndigits digits to first:
*/
i = 5;
while (ndigits < i) *ascii++ = 48, --i;
while (ndigits >= first) *ascii++ = digits[--ndigits];
/* Don't output the trailing zeros! */
}
}
else
*ascii++ = 48;
/* And null terminate the string: */
*ascii = 0;
return;
}
}
/* Here on buffer too small. */
png_error(png_ptr, "ASCII conversion buffer too small");
} | /* Function to format a fixed point value in ASCII.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3013-L3080 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_muldiv | int
png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
png_int_32 divisor)
{
/* Return a * times / divisor, rounded. */
if (divisor != 0)
{
if (a == 0 || times == 0)
{
*res = 0;
return 1;
}
else
{
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
double r = a;
r *= times;
r /= divisor;
r = floor(r+.5);
/* A png_fixed_point is a 32-bit integer. */
if (r <= 2147483647. && r >= -2147483648.)
{
*res = (png_fixed_point)r;
return 1;
}
#else
int negative = 0;
png_uint_32 A, T, D;
png_uint_32 s16, s32, s00;
if (a < 0)
negative = 1, A = -a;
else
A = a;
if (times < 0)
negative = !negative, T = -times;
else
T = times;
if (divisor < 0)
negative = !negative, D = -divisor;
else
D = divisor;
/* Following can't overflow because the arguments only
* have 31 bits each, however the result may be 32 bits.
*/
s16 = (A >> 16) * (T & 0xffff) +
(A & 0xffff) * (T >> 16);
/* Can't overflow because the a*times bit is only 30
* bits at most.
*/
s32 = (A >> 16) * (T >> 16) + (s16 >> 16);
s00 = (A & 0xffff) * (T & 0xffff);
s16 = (s16 & 0xffff) << 16;
s00 += s16;
if (s00 < s16)
++s32; /* carry */
if (s32 < D) /* else overflow */
{
/* s32.s00 is now the 64-bit product, do a standard
* division, we know that s32 < D, so the maximum
* required shift is 31.
*/
int bitshift = 32;
png_fixed_point result = 0; /* NOTE: signed */
while (--bitshift >= 0)
{
png_uint_32 d32, d00;
if (bitshift > 0)
d32 = D >> (32-bitshift), d00 = D << bitshift;
else
d32 = 0, d00 = D;
if (s32 > d32)
{
if (s00 < d00) --s32; /* carry */
s32 -= d32, s00 -= d00, result += 1<<bitshift;
}
else
if (s32 == d32 && s00 >= d00)
s32 = 0, s00 -= d00, result += 1<<bitshift;
}
/* Handle the rounding. */
if (s00 >= (D >> 1))
++result;
if (negative)
result = -result;
/* Check for overflow. */
if ((negative && result <= 0) || (!negative && result >= 0))
{
*res = result;
return 1;
}
}
#endif
}
}
return 0;
} | /* muldiv functions */
/* This API takes signed arguments and rounds the result to the nearest
* integer (or, for a fixed point number - the standard argument - to
* the nearest .00001). Overflow and divide by zero are signalled in
* the result, a boolean - true on success, false on overflow.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3111-L3223 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_muldiv_warn | png_fixed_point
png_muldiv_warn(png_const_structrp png_ptr, png_fixed_point a, png_int_32 times,
png_int_32 divisor)
{
png_fixed_point result;
if (png_muldiv(&result, a, times, divisor))
return result;
png_warning(png_ptr, "fixed point overflow ignored");
return 0;
} | /* The following is for when the caller doesn't much care about the
* result.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3230-L3241 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_reciprocal | png_fixed_point
png_reciprocal(png_fixed_point a)
{
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
double r = floor(1E10/a+.5);
if (r <= 2147483647. && r >= -2147483648.)
return (png_fixed_point)r;
#else
png_fixed_point res;
if (png_muldiv(&res, 100000, 100000, a))
return res;
#endif
return 0; /* error/overflow */
} | /* more fixed point functions for gamma */
/* Calculate a reciprocal, return 0 on div-by-zero or overflow. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3246-L3262 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_gamma_significant | int /* PRIVATE */
png_gamma_significant(png_fixed_point gamma_val)
{
return gamma_val < PNG_FP_1 - PNG_GAMMA_THRESHOLD_FIXED ||
gamma_val > PNG_FP_1 + PNG_GAMMA_THRESHOLD_FIXED;
} | /* This is the shared test on whether a gamma value is 'significant' - whether
* it is worth doing gamma correction.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3267-L3272 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_product2 | static png_fixed_point
png_product2(png_fixed_point a, png_fixed_point b)
{
/* The required result is 1/a * 1/b; the following preserves accuracy. */
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
double r = a * 1E-5;
r *= b;
r = floor(r+.5);
if (r <= 2147483647. && r >= -2147483648.)
return (png_fixed_point)r;
#else
png_fixed_point res;
if (png_muldiv(&res, a, b, 100000))
return res;
#endif
return 0; /* overflow */
} | /* A local convenience routine. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3277-L3296 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_reciprocal2 | png_fixed_point
png_reciprocal2(png_fixed_point a, png_fixed_point b)
{
/* The required result is 1/a * 1/b; the following preserves accuracy. */
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
double r = 1E15/a;
r /= b;
r = floor(r+.5);
if (r <= 2147483647. && r >= -2147483648.)
return (png_fixed_point)r;
#else
/* This may overflow because the range of png_fixed_point isn't symmetric,
* but this API is only used for the product of file and screen gamma so it
* doesn't matter that the smallest number it can produce is 1/21474, not
* 1/100000
*/
png_fixed_point res = png_product2(a, b);
if (res != 0)
return png_reciprocal(res);
#endif
return 0; /* overflow */
} | /* The inverse of the above. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3299-L3323 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_log16bit | static png_int_32
png_log16bit(png_uint_32 x)
{
unsigned int lg2 = 0;
/* As above, but now the input has 16 bits. */
if ((x &= 0xffff) == 0)
return -1;
if ((x & 0xff00) == 0)
lg2 = 8, x <<= 8;
if ((x & 0xf000) == 0)
lg2 += 4, x <<= 4;
if ((x & 0xc000) == 0)
lg2 += 2, x <<= 2;
if ((x & 0x8000) == 0)
lg2 += 1, x <<= 1;
/* Calculate the base logarithm from the top 8 bits as a 28-bit fractional
* value.
*/
lg2 <<= 28;
lg2 += (png_8bit_l2[(x>>8)-128]+8) >> 4;
/* Now we need to interpolate the factor, this requires a division by the top
* 8 bits. Do this with maximum precision.
*/
x = ((x << 16) + (x >> 9)) / (x >> 8);
/* Since we divided by the top 8 bits of 'x' there will be a '1' at 1<<24,
* the value at 1<<16 (ignoring this) will be 0 or 1; this gives us exactly
* 16 bits to interpolate to get the low bits of the result. Round the
* answer. Note that the end point values are scaled by 64 to retain overall
* precision and that 'lg2' is current scaled by an extra 12 bits, so adjust
* the overall scaling by 6-12. Round at every step.
*/
x -= 1U << 24;
if (x <= 65536U) /* <= '257' */
lg2 += ((23591U * (65536U-x)) + (1U << (16+6-12-1))) >> (16+6-12);
else
lg2 -= ((23499U * (x-65536U)) + (1U << (16+6-12-1))) >> (16+6-12);
/* Safe, because the result can't have more than 20 bits: */
return (png_int_32)((lg2 + 2048) >> 12);
} | /* The above gives exact (to 16 binary places) log2 values for 8-bit images,
* for 16-bit images we use the most significant 8 bits of the 16-bit value to
* get an approximation then multiply the approximation by a correction factor
* determined by the remaining up to 8 bits. This requires an additional step
* in the 16-bit case.
*
* We want log2(value/65535), we have log2(v'/255), where:
*
* value = v' * 256 + v''
* = v' * f
*
* So f is value/v', which is equal to (256+v''/v') since v' is in the range 128
* to 255 and v'' is in the range 0 to 255 f will be in the range 256 to less
* than 258. The final factor also needs to correct for the fact that our 8-bit
* value is scaled by 255, whereas the 16-bit values must be scaled by 65535.
*
* This gives a final formula using a calculated value 'x' which is value/v' and
* scaling by 65536 to match the above table:
*
* log2(x/257) * 65536
*
* Since these numbers are so close to '1' we can use simple linear
* interpolation between the two end values 256/257 (result -368.61) and 258/257
* (result 367.179). The values used below are scaled by a further 64 to give
* 16-bit precision in the interpolation:
*
* Start (256): -23591
* Zero (257): 0
* End (258): 23499
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3448-L3497 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_gamma_8bit_correct | png_byte
png_gamma_8bit_correct(unsigned int value, png_fixed_point gamma_val)
{
if (value > 0 && value < 255)
{
# ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
double r = floor(255*pow(value/255.,gamma_val*.00001)+.5);
return (png_byte)r;
# else
png_int_32 lg2 = png_log8bit(value);
png_fixed_point res;
if (png_muldiv(&res, gamma_val, lg2, PNG_FP_1))
return png_exp8bit(res);
/* Overflow. */
value = 0;
# endif
}
return (png_byte)value;
} | /* FLOATING_ARITHMETIC */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3613-L3634 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_gamma_correct | png_uint_16 /* PRIVATE */
png_gamma_correct(png_structrp png_ptr, unsigned int value,
png_fixed_point gamma_val)
{
if (png_ptr->bit_depth == 8)
return png_gamma_8bit_correct(value, gamma_val);
else
return png_gamma_16bit_correct(value, gamma_val);
} | /* This does the right thing based on the bit_depth field of the
* png_struct, interpreting values as 8-bit or 16-bit. While the result
* is nominally a 16-bit value if bit depth is 8 then the result is
* 8-bit (as are the arguments.)
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3664-L3673 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_build_16bit_table | static void
png_build_16bit_table(png_structrp png_ptr, png_uint_16pp *ptable,
PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
{
/* Various values derived from 'shift': */
PNG_CONST unsigned int num = 1U << (8U - shift);
PNG_CONST unsigned int max = (1U << (16U - shift))-1U;
PNG_CONST unsigned int max_by_2 = 1U << (15U-shift);
unsigned int i;
png_uint_16pp table = *ptable =
(png_uint_16pp)png_calloc(png_ptr, num * (sizeof (png_uint_16p)));
for (i = 0; i < num; i++)
{
png_uint_16p sub_table = table[i] =
(png_uint_16p)png_malloc(png_ptr, 256 * (sizeof (png_uint_16)));
/* The 'threshold' test is repeated here because it can arise for one of
* the 16-bit tables even if the others don't hit it.
*/
if (png_gamma_significant(gamma_val))
{
/* The old code would overflow at the end and this would cause the
* 'pow' function to return a result >1, resulting in an
* arithmetic error. This code follows the spec exactly; ig is
* the recovered input sample, it always has 8-16 bits.
*
* We want input * 65535/max, rounded, the arithmetic fits in 32
* bits (unsigned) so long as max <= 32767.
*/
unsigned int j;
for (j = 0; j < 256; j++)
{
png_uint_32 ig = (j << (8-shift)) + i;
# ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
/* Inline the 'max' scaling operation: */
double d = floor(65535*pow(ig/(double)max, gamma_val*.00001)+.5);
sub_table[j] = (png_uint_16)d;
# else
if (shift)
ig = (ig * 65535U + max_by_2)/max;
sub_table[j] = png_gamma_16bit_correct(ig, gamma_val);
# endif
}
}
else
{
/* We must still build a table, but do it the fast way. */
unsigned int j;
for (j = 0; j < 256; j++)
{
png_uint_32 ig = (j << (8-shift)) + i;
if (shift)
ig = (ig * 65535U + max_by_2)/max;
sub_table[j] = (png_uint_16)ig;
}
}
}
} | /* Internal function to build a single 16-bit table - the table consists of
* 'num' 256 entry subtables, where 'num' is determined by 'shift' - the amount
* to shift the input values right (or 16-number_of_signifiant_bits).
*
* The caller is responsible for ensuring that the table gets cleaned up on
* png_error (i.e. if one of the mallocs below fails) - i.e. the *table argument
* should be somewhere that will be cleaned.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3683-L3746 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_build_16to8_table | static void
png_build_16to8_table(png_structrp png_ptr, png_uint_16pp *ptable,
PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
{
PNG_CONST unsigned int num = 1U << (8U - shift);
PNG_CONST unsigned int max = (1U << (16U - shift))-1U;
unsigned int i;
png_uint_32 last;
png_uint_16pp table = *ptable =
(png_uint_16pp)png_calloc(png_ptr, num * (sizeof (png_uint_16p)));
/* 'num' is the number of tables and also the number of low bits of low
* bits of the input 16-bit value used to select a table. Each table is
* itself index by the high 8 bits of the value.
*/
for (i = 0; i < num; i++)
table[i] = (png_uint_16p)png_malloc(png_ptr,
256 * (sizeof (png_uint_16)));
/* 'gamma_val' is set to the reciprocal of the value calculated above, so
* pow(out,g) is an *input* value. 'last' is the last input value set.
*
* In the loop 'i' is used to find output values. Since the output is
* 8-bit there are only 256 possible values. The tables are set up to
* select the closest possible output value for each input by finding
* the input value at the boundary between each pair of output values
* and filling the table up to that boundary with the lower output
* value.
*
* The boundary values are 0.5,1.5..253.5,254.5. Since these are 9-bit
* values the code below uses a 16-bit value in i; the values start at
* 128.5 (for 0.5) and step by 257, for a total of 254 values (the last
* entries are filled with 255). Start i at 128 and fill all 'last'
* table entries <= 'max'
*/
last = 0;
for (i = 0; i < 255; ++i) /* 8-bit output value */
{
/* Find the corresponding maximum input value */
png_uint_16 out = (png_uint_16)(i * 257U); /* 16-bit output value */
/* Find the boundary value in 16 bits: */
png_uint_32 bound = png_gamma_16bit_correct(out+128U, gamma_val);
/* Adjust (round) to (16-shift) bits: */
bound = (bound * max + 32768U)/65535U + 1U;
while (last < bound)
{
table[last & (0xffU >> shift)][last >> (8U - shift)] = out;
last++;
}
}
/* And fill in the final entries. */
while (last < (num << 8))
{
table[last & (0xff >> shift)][last >> (8U - shift)] = 65535U;
last++;
}
} | /* NOTE: this function expects the *inverse* of the overall gamma transformation
* required.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3751-L3812 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_build_8bit_table | static void
png_build_8bit_table(png_structrp png_ptr, png_bytepp ptable,
PNG_CONST png_fixed_point gamma_val)
{
unsigned int i;
png_bytep table = *ptable = (png_bytep)png_malloc(png_ptr, 256);
if (png_gamma_significant(gamma_val)) for (i=0; i<256; i++)
table[i] = png_gamma_8bit_correct(i, gamma_val);
else for (i=0; i<256; ++i)
table[i] = (png_byte)i;
} | /* Build a single 8-bit table: same as the 16-bit case but much simpler (and
* typically much faster). Note that libpng currently does no sBIT processing
* (apparently contrary to the spec) so a 256 entry table is always generated.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3818-L3830 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_destroy_gamma_table | void /* PRIVATE */
png_destroy_gamma_table(png_structrp png_ptr)
{
png_free(png_ptr, png_ptr->gamma_table);
png_ptr->gamma_table = NULL;
if (png_ptr->gamma_16_table != NULL)
{
int i;
int istop = (1 << (8 - png_ptr->gamma_shift));
for (i = 0; i < istop; i++)
{
png_free(png_ptr, png_ptr->gamma_16_table[i]);
}
png_free(png_ptr, png_ptr->gamma_16_table);
png_ptr->gamma_16_table = NULL;
}
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
png_free(png_ptr, png_ptr->gamma_from_1);
png_ptr->gamma_from_1 = NULL;
png_free(png_ptr, png_ptr->gamma_to_1);
png_ptr->gamma_to_1 = NULL;
if (png_ptr->gamma_16_from_1 != NULL)
{
int i;
int istop = (1 << (8 - png_ptr->gamma_shift));
for (i = 0; i < istop; i++)
{
png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
}
png_free(png_ptr, png_ptr->gamma_16_from_1);
png_ptr->gamma_16_from_1 = NULL;
}
if (png_ptr->gamma_16_to_1 != NULL)
{
int i;
int istop = (1 << (8 - png_ptr->gamma_shift));
for (i = 0; i < istop; i++)
{
png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
}
png_free(png_ptr, png_ptr->gamma_16_to_1);
png_ptr->gamma_16_to_1 = NULL;
}
#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
} | /* Used from png_read_destroy and below to release the memory used by the gamma
* tables.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3835-L3884 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_build_gamma_table | void /* PRIVATE */
png_build_gamma_table(png_structrp png_ptr, int bit_depth)
{
png_debug(1, "in png_build_gamma_table");
/* Remove any existing table; this copes with multiple calls to
* png_read_update_info. The warning is because building the gamma tables
* multiple times is a performance hit - it's harmless but the ability to call
* png_read_update_info() multiple times is new in 1.5.6 so it seems sensible
* to warn if the app introduces such a hit.
*/
if (png_ptr->gamma_table != NULL || png_ptr->gamma_16_table != NULL)
{
png_warning(png_ptr, "gamma table being rebuilt");
png_destroy_gamma_table(png_ptr);
}
if (bit_depth <= 8)
{
png_build_8bit_table(png_ptr, &png_ptr->gamma_table,
png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->colorspace.gamma,
png_ptr->screen_gamma) : PNG_FP_1);
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
{
png_build_8bit_table(png_ptr, &png_ptr->gamma_to_1,
png_reciprocal(png_ptr->colorspace.gamma));
png_build_8bit_table(png_ptr, &png_ptr->gamma_from_1,
png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
}
#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
}
else
{
png_byte shift, sig_bit;
if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
{
sig_bit = png_ptr->sig_bit.red;
if (png_ptr->sig_bit.green > sig_bit)
sig_bit = png_ptr->sig_bit.green;
if (png_ptr->sig_bit.blue > sig_bit)
sig_bit = png_ptr->sig_bit.blue;
}
else
sig_bit = png_ptr->sig_bit.gray;
/* 16-bit gamma code uses this equation:
*
* ov = table[(iv & 0xff) >> gamma_shift][iv >> 8]
*
* Where 'iv' is the input color value and 'ov' is the output value -
* pow(iv, gamma).
*
* Thus the gamma table consists of up to 256 256 entry tables. The table
* is selected by the (8-gamma_shift) most significant of the low 8 bits of
* the color value then indexed by the upper 8 bits:
*
* table[low bits][high 8 bits]
*
* So the table 'n' corresponds to all those 'iv' of:
*
* <all high 8-bit values><n << gamma_shift>..<(n+1 << gamma_shift)-1>
*
*/
if (sig_bit > 0 && sig_bit < 16U)
shift = (png_byte)(16U - sig_bit); /* shift == insignificant bits */
else
shift = 0; /* keep all 16 bits */
if (png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8))
{
/* PNG_MAX_GAMMA_8 is the number of bits to keep - effectively
* the significant bits in the *input* when the output will
* eventually be 8 bits. By default it is 11.
*/
if (shift < (16U - PNG_MAX_GAMMA_8))
shift = (16U - PNG_MAX_GAMMA_8);
}
if (shift > 8U)
shift = 8U; /* Guarantees at least one table! */
png_ptr->gamma_shift = shift;
#ifdef PNG_16BIT_SUPPORTED
/* NOTE: prior to 1.5.4 this test used to include PNG_BACKGROUND (now
* PNG_COMPOSE). This effectively smashed the background calculation for
* 16-bit output because the 8-bit table assumes the result will be reduced
* to 8 bits.
*/
if (png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8))
#endif
png_build_16to8_table(png_ptr, &png_ptr->gamma_16_table, shift,
png_ptr->screen_gamma > 0 ? png_product2(png_ptr->colorspace.gamma,
png_ptr->screen_gamma) : PNG_FP_1);
#ifdef PNG_16BIT_SUPPORTED
else
png_build_16bit_table(png_ptr, &png_ptr->gamma_16_table, shift,
png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->colorspace.gamma,
png_ptr->screen_gamma) : PNG_FP_1);
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
{
png_build_16bit_table(png_ptr, &png_ptr->gamma_16_to_1, shift,
png_reciprocal(png_ptr->colorspace.gamma));
/* Notice that the '16 from 1' table should be full precision, however
* the lookup on this table still uses gamma_shift, so it can't be.
* TODO: fix this.
*/
png_build_16bit_table(png_ptr, &png_ptr->gamma_16_from_1, shift,
png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
}
#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
}
} | /* We build the 8- or 16-bit gamma tables here. Note that for 16-bit
* tables, we don't make a full table if we are reducing to 8-bit in
* the future. Note also how the gamma_16 tables are segmented so that
* we don't need to allocate > 64K chunks for a full 16-bit table.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/png.c#L3891-L4021 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_safecat | size_t
png_safecat(png_charp buffer, size_t bufsize, size_t pos,
png_const_charp string)
{
if (buffer != NULL && pos < bufsize)
{
if (string != NULL)
while (*string != '\0' && pos < bufsize-1)
buffer[pos++] = *string++;
buffer[pos] = '\0';
}
return pos;
} | /* PNG_ERROR_TEXT_SUPPORTED */
/* Utility to safely appends strings to a buffer. This never errors out so
* error checking is not required in the caller.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L111-L125 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_format_number | png_charp
png_format_number(png_const_charp start, png_charp end, int format,
png_alloc_size_t number)
{
int count = 0; /* number of digits output */
int mincount = 1; /* minimum number required */
int output = 0; /* digit output (for the fixed point format) */
*--end = '\0';
/* This is written so that the loop always runs at least once, even with
* number zero.
*/
while (end > start && (number != 0 || count < mincount))
{
static const char digits[] = "0123456789ABCDEF";
switch (format)
{
case PNG_NUMBER_FORMAT_fixed:
/* Needs five digits (the fraction) */
mincount = 5;
if (output || number % 10 != 0)
{
*--end = digits[number % 10];
output = 1;
}
number /= 10;
break;
case PNG_NUMBER_FORMAT_02u:
/* Expects at least 2 digits. */
mincount = 2;
/* FALL THROUGH */
case PNG_NUMBER_FORMAT_u:
*--end = digits[number % 10];
number /= 10;
break;
case PNG_NUMBER_FORMAT_02x:
/* This format expects at least two digits */
mincount = 2;
/* FALL THROUGH */
case PNG_NUMBER_FORMAT_x:
*--end = digits[number & 0xf];
number >>= 4;
break;
default: /* an error */
number = 0;
break;
}
/* Keep track of the number of digits added */
++count;
/* Float a fixed number here: */
if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start)
{
/* End of the fraction, but maybe nothing was output? In that case
* drop the decimal point. If the number is a true zero handle that
* here.
*/
if (output)
*--end = '.';
else if (number == 0) /* and !output */
*--end = '0';
}
}
return end;
} | /* Utility to dump an unsigned value into a buffer, given a start pointer and
* and end pointer (which should point just *beyond* the end of the buffer!)
* Returns the pointer to the start of the formatted string.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L132-L206 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_warning | void PNGAPI
png_warning(png_const_structrp png_ptr, png_const_charp warning_message)
{
int offset = 0;
if (png_ptr != NULL)
{
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
if (png_ptr->flags&
(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
#endif
{
if (*warning_message == PNG_LITERAL_SHARP)
{
for (offset = 1; offset < 15; offset++)
if (warning_message[offset] == ' ')
break;
}
}
}
if (png_ptr != NULL && png_ptr->warning_fn != NULL)
(*(png_ptr->warning_fn))(png_constcast(png_structrp,png_ptr),
warning_message + offset);
else
png_default_warning(png_ptr, warning_message + offset);
} | /* This function is called whenever there is a non-fatal error. This function
* should not be changed. If there is a need to handle warnings differently,
* you should supply a replacement warning function and use
* png_set_error_fn() to replace the warning function at run-time.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L215-L239 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_warning_parameter | void
png_warning_parameter(png_warning_parameters p, int number,
png_const_charp string)
{
if (number > 0 && number <= PNG_WARNING_PARAMETER_COUNT)
(void)png_safecat(p[number-1], (sizeof p[number-1]), 0, string);
} | /* These functions support 'formatted' warning messages with up to
* PNG_WARNING_PARAMETER_COUNT parameters. In the format string the parameter
* is introduced by @<number>, where 'number' starts at 1. This follows the
* standard established by X/Open for internationalizable error messages.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L246-L252 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_chunk_report | void /* PRIVATE */
png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
{
/* This is always supported, but for just read or just write it
* unconditionally does the right thing.
*/
# if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
if (png_ptr->mode & PNG_IS_READ_STRUCT)
# endif
# ifdef PNG_READ_SUPPORTED
{
if (error < PNG_CHUNK_ERROR)
png_chunk_warning(png_ptr, message);
else
png_chunk_benign_error(png_ptr, message);
}
# endif
# if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
else if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
# endif
# ifdef PNG_WRITE_SUPPORTED
{
if (error < PNG_CHUNK_WRITE_ERROR)
png_app_warning(png_ptr, message);
else
png_app_error(png_ptr, message);
}
# endif
} | /* PNG_READ_SUPPORTED */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L513-L546 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_default_warning | static void /* PRIVATE */
png_default_warning(png_const_structrp png_ptr, png_const_charp warning_message)
{
#ifdef PNG_CONSOLE_IO_SUPPORTED
# ifdef PNG_ERROR_NUMBERS_SUPPORTED
if (*warning_message == PNG_LITERAL_SHARP)
{
int offset;
char warning_number[16];
for (offset = 0; offset < 15; offset++)
{
warning_number[offset] = warning_message[offset + 1];
if (warning_message[offset] == ' ')
break;
}
if ((offset > 1) && (offset < 15))
{
warning_number[offset + 1] = '\0';
fprintf(stderr, "libpng warning no. %s: %s",
warning_number, warning_message + offset);
fprintf(stderr, PNG_STRING_NEWLINE);
}
else
{
fprintf(stderr, "libpng warning: %s",
warning_message);
fprintf(stderr, PNG_STRING_NEWLINE);
}
}
else
# endif
{
fprintf(stderr, "libpng warning: %s", warning_message);
fprintf(stderr, PNG_STRING_NEWLINE);
}
#else
PNG_UNUSED(warning_message) /* Make compiler happy */
#endif
PNG_UNUSED(png_ptr) /* Make compiler happy */
} | /* This function is called when there is a warning, but the library thinks
* it can continue anyway. Replacement functions don't have to do anything
* here if you don't want them to. In the default configuration, png_ptr is
* not used, but it is passed in case it may be useful.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L753-L795 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_error_fn | void PNGAPI
png_set_error_fn(png_structrp png_ptr, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warning_fn)
{
if (png_ptr == NULL)
return;
png_ptr->error_ptr = error_ptr;
png_ptr->error_fn = error_fn;
#ifdef PNG_WARNINGS_SUPPORTED
png_ptr->warning_fn = warning_fn;
#else
PNG_UNUSED(warning_fn)
#endif
} | /* PNG_WARNINGS_SUPPORTED */
/* This function is called when the application wants to use another method
* of handling errors and warnings. Note that the error function MUST NOT
* return to the calling routine or serious problems will occur. The return
* method used in the default routine calls longjmp(png_ptr->jmp_buf_ptr, 1)
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L803-L817 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_get_error_ptr | png_voidp PNGAPI
png_get_error_ptr(png_const_structrp png_ptr)
{
if (png_ptr == NULL)
return NULL;
return ((png_voidp)png_ptr->error_ptr);
} | /* This function returns a pointer to the error_ptr associated with the user
* functions. The application should free any memory associated with this
* pointer before png_write_destroy and png_read_destroy are called.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngerror.c#L824-L831 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_get_image_width | png_uint_32 PNGAPI
png_get_image_width(png_const_structrp png_ptr, png_const_inforp info_ptr)
{
if (png_ptr != NULL && info_ptr != NULL)
return info_ptr->width;
return (0);
} | /* Easy access to info, added in libpng-0.99 */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngget.c#L51-L58 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_get_sCAL_s | png_uint_32 PNGAPI
png_get_sCAL_s(png_const_structrp png_ptr, png_const_inforp info_ptr,
int *unit, png_charpp width, png_charpp height)
{
if (png_ptr != NULL && info_ptr != NULL &&
(info_ptr->valid & PNG_INFO_sCAL))
{
*unit = info_ptr->scal_unit;
*width = info_ptr->scal_s_width;
*height = info_ptr->scal_s_height;
return (PNG_INFO_sCAL);
}
return(0);
} | /* FLOATING POINT */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngget.c#L888-L902 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_get_user_width_max | png_uint_32 PNGAPI
png_get_user_width_max (png_const_structrp png_ptr)
{
return (png_ptr ? png_ptr->user_width_max : 0);
} | /* These functions were added to libpng 1.2.6 and were enabled
* by default in libpng-1.4.0 */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngget.c#L1122-L1126 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_get_chunk_cache_max | png_uint_32 PNGAPI
png_get_chunk_cache_max (png_const_structrp png_ptr)
{
return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
} | /* This function was added to libpng 1.4.0 */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngget.c#L1135-L1139 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_get_chunk_malloc_max | png_alloc_size_t PNGAPI
png_get_chunk_malloc_max (png_const_structrp png_ptr)
{
return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
} | /* This function was added to libpng 1.4.1 */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngget.c#L1142-L1146 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_destroy_png_struct | void /* PRIVATE */
png_destroy_png_struct(png_structrp png_ptr)
{
if (png_ptr != NULL)
{
/* png_free might call png_error and may certainly call
* png_get_mem_ptr, so fake a temporary png_struct to support this.
*/
png_struct dummy_struct = *png_ptr;
memset(png_ptr, 0, (sizeof *png_ptr));
png_free(&dummy_struct, png_ptr);
# ifdef PNG_SETJMP_SUPPORTED
/* We may have a jmp_buf left to deallocate. */
png_free_jmpbuf(&dummy_struct);
# endif
}
} | /* Free a png_struct */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngmem.c#L24-L41 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_malloc_array_checked | static png_voidp
png_malloc_array_checked(png_const_structrp png_ptr, int nelements,
size_t element_size)
{
png_alloc_size_t req = nelements; /* known to be > 0 */
if (req <= PNG_SIZE_MAX/element_size)
return png_malloc_base(png_ptr, req * element_size);
/* The failure case when the request is too large */
return NULL;
} | /* This is really here only to work round a spurious warning in GCC 4.6 and 4.7
* that arises because of the checks in png_realloc_array that are repeated in
* png_malloc_array.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngmem.c#L102-L113 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_free | void PNGAPI
png_free(png_const_structrp png_ptr, png_voidp ptr)
{
if (png_ptr == NULL || ptr == NULL)
return;
#ifdef PNG_USER_MEM_SUPPORTED
if (png_ptr->free_fn != NULL)
png_ptr->free_fn(png_constcast(png_structrp,png_ptr), ptr);
else
png_free_default(png_ptr, ptr);
}
PNG_FUNCTION(void,PNGAPI
png_free_default,(png_const_structrp png_ptr, png_voidp ptr),PNG_DEPRECATED)
{
if (png_ptr == NULL || ptr == NULL)
return;
#endif /* PNG_USER_MEM_SUPPORTED */
free(ptr);
} | /* Free a pointer allocated by png_malloc(). If ptr is NULL, return
* without taking any action.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngmem.c#L224-L246 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_mem_fn | void PNGAPI
png_set_mem_fn(png_structrp png_ptr, png_voidp mem_ptr, png_malloc_ptr
malloc_fn, png_free_ptr free_fn)
{
if (png_ptr != NULL)
{
png_ptr->mem_ptr = mem_ptr;
png_ptr->malloc_fn = malloc_fn;
png_ptr->free_fn = free_fn;
}
} | /* This function is called when the application wants to use another method
* of allocating and freeing memory.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngmem.c#L252-L262 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_get_mem_ptr | png_voidp PNGAPI
png_get_mem_ptr(png_const_structrp png_ptr)
{
if (png_ptr == NULL)
return NULL;
return png_ptr->mem_ptr;
} | /* This function returns a pointer to the mem_ptr associated with the user
* functions. The application should free any memory associated with this
* pointer before png_write_destroy and png_read_destroy are called.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngmem.c#L268-L275 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_process_some_data | void /* PRIVATE */
png_process_some_data(png_structrp png_ptr, png_inforp info_ptr)
{
if (png_ptr == NULL)
return;
switch (png_ptr->process_mode)
{
case PNG_READ_SIG_MODE:
{
png_push_read_sig(png_ptr, info_ptr);
break;
}
case PNG_READ_CHUNK_MODE:
{
png_push_read_chunk(png_ptr, info_ptr);
break;
}
case PNG_READ_IDAT_MODE:
{
png_push_read_IDAT(png_ptr);
break;
}
case PNG_SKIP_MODE:
{
png_push_crc_finish(png_ptr);
break;
}
default:
{
png_ptr->buffer_size = 0;
break;
}
}
} | /* What we do with the incoming data depends on what we were previously
* doing before we ran out of data...
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngpread.c#L105-L143 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_push_read_sig | void /* PRIVATE */
png_push_read_sig(png_structrp png_ptr, png_inforp info_ptr)
{
png_size_t num_checked = png_ptr->sig_bytes,
num_to_check = 8 - num_checked;
if (png_ptr->buffer_size < num_to_check)
{
num_to_check = png_ptr->buffer_size;
}
png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
num_to_check);
png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes + num_to_check);
if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
{
if (num_checked < 4 &&
png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
png_error(png_ptr, "Not a PNG file");
else
png_error(png_ptr, "PNG file corrupted by ASCII conversion");
}
else
{
if (png_ptr->sig_bytes >= 8)
{
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
}
}
} | /* Read any remaining signature bytes from the stream and compare them with
* the correct PNG signature. It is possible that this routine is called
* with bytes already read from the signature, either because they have been
* checked by the calling application, or because of multiple calls to this
* routine.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngpread.c#L151-L182 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_progressive_read_fn | void PNGAPI
png_set_progressive_read_fn(png_structrp png_ptr, png_voidp progressive_ptr,
png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
png_progressive_end_ptr end_fn)
{
if (png_ptr == NULL)
return;
png_ptr->info_fn = info_fn;
png_ptr->row_fn = row_fn;
png_ptr->end_fn = end_fn;
png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer);
} | /* PNG_READ_INTERLACING_SUPPORTED */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngpread.c#L1268-L1281 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_read_info | void PNGAPI
png_read_info(png_structrp png_ptr, png_inforp info_ptr)
{
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
int keep;
#endif
png_debug(1, "in png_read_info");
if (png_ptr == NULL || info_ptr == NULL)
return;
/* Read and check the PNG file signature. */
png_read_sig(png_ptr, info_ptr);
for (;;)
{
png_uint_32 length = png_read_chunk_header(png_ptr);
png_uint_32 chunk_name = png_ptr->chunk_name;
/* IDAT logic needs to happen here to simplify getting the two flags
* right.
*/
if (chunk_name == png_IDAT)
{
if (!(png_ptr->mode & PNG_HAVE_IHDR))
png_chunk_error(png_ptr, "Missing IHDR before IDAT");
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
!(png_ptr->mode & PNG_HAVE_PLTE))
png_chunk_error(png_ptr, "Missing PLTE before IDAT");
else if (png_ptr->mode & PNG_AFTER_IDAT)
png_chunk_benign_error(png_ptr, "Too many IDATs found");
png_ptr->mode |= PNG_HAVE_IDAT;
}
else if (png_ptr->mode & PNG_HAVE_IDAT)
png_ptr->mode |= PNG_AFTER_IDAT;
/* This should be a binary subdivision search or a hash for
* matching the chunk name rather than a linear search.
*/
if (chunk_name == png_IHDR)
png_handle_IHDR(png_ptr, info_ptr, length);
else if (chunk_name == png_IEND)
png_handle_IEND(png_ptr, info_ptr, length);
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
else if ((keep = png_chunk_unknown_handling(png_ptr, chunk_name)) != 0)
{
png_handle_unknown(png_ptr, info_ptr, length, keep);
if (chunk_name == png_PLTE)
png_ptr->mode |= PNG_HAVE_PLTE;
else if (chunk_name == png_IDAT)
{
png_ptr->idat_size = 0; /* It has been consumed */
break;
}
}
#endif
else if (chunk_name == png_PLTE)
png_handle_PLTE(png_ptr, info_ptr, length);
else if (chunk_name == png_IDAT)
{
png_ptr->idat_size = length;
break;
}
#ifdef PNG_READ_bKGD_SUPPORTED
else if (chunk_name == png_bKGD)
png_handle_bKGD(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_cHRM_SUPPORTED
else if (chunk_name == png_cHRM)
png_handle_cHRM(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_gAMA_SUPPORTED
else if (chunk_name == png_gAMA)
png_handle_gAMA(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_hIST_SUPPORTED
else if (chunk_name == png_hIST)
png_handle_hIST(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_oFFs_SUPPORTED
else if (chunk_name == png_oFFs)
png_handle_oFFs(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_pCAL_SUPPORTED
else if (chunk_name == png_pCAL)
png_handle_pCAL(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sCAL_SUPPORTED
else if (chunk_name == png_sCAL)
png_handle_sCAL(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_pHYs_SUPPORTED
else if (chunk_name == png_pHYs)
png_handle_pHYs(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sBIT_SUPPORTED
else if (chunk_name == png_sBIT)
png_handle_sBIT(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sRGB_SUPPORTED
else if (chunk_name == png_sRGB)
png_handle_sRGB(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_iCCP_SUPPORTED
else if (chunk_name == png_iCCP)
png_handle_iCCP(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sPLT_SUPPORTED
else if (chunk_name == png_sPLT)
png_handle_sPLT(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_tEXt_SUPPORTED
else if (chunk_name == png_tEXt)
png_handle_tEXt(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_tIME_SUPPORTED
else if (chunk_name == png_tIME)
png_handle_tIME(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_tRNS_SUPPORTED
else if (chunk_name == png_tRNS)
png_handle_tRNS(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_zTXt_SUPPORTED
else if (chunk_name == png_zTXt)
png_handle_zTXt(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_iTXt_SUPPORTED
else if (chunk_name == png_iTXt)
png_handle_iTXt(png_ptr, info_ptr, length);
#endif
else
png_handle_unknown(png_ptr, info_ptr, length,
PNG_HANDLE_CHUNK_AS_DEFAULT);
}
} | /* Read the information before the actual image data. This has been
* changed in v0.90 to allow reading a file that already has the magic
* bytes read from the stream. You can tell libpng how many bytes have
* been read from the beginning of the stream (up to the maximum of 8)
* via png_set_sig_bytes(), and we will only check the remaining bytes
* here. The application can then have access to the signature bytes we
* read if it is determined that this isn't a valid PNG file.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L91-L254 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_start_read_image | void PNGAPI
png_start_read_image(png_structrp png_ptr)
{
png_debug(1, "in png_start_read_image");
if (png_ptr != NULL)
{
if ((png_ptr->flags & PNG_FLAG_ROW_INIT) == 0)
png_read_start_row(png_ptr);
/* New in 1.6.0 this avoids the bug of doing the initializations twice */
else
png_app_error(png_ptr,
"png_start_read_image/png_read_update_info: duplicate call");
}
} | /* Initialize palette, background, etc, after transformations
* are set, but before any reading takes place. This allows
* the user to obtain a gamma-corrected palette, for example.
* If the user doesn't call this, we will do it ourselves.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L289-L304 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_read_rows | void PNGAPI
png_read_rows(png_structrp png_ptr, png_bytepp row,
png_bytepp display_row, png_uint_32 num_rows)
{
png_uint_32 i;
png_bytepp rp;
png_bytepp dp;
png_debug(1, "in png_read_rows");
if (png_ptr == NULL)
return;
rp = row;
dp = display_row;
if (rp != NULL && dp != NULL)
for (i = 0; i < num_rows; i++)
{
png_bytep rptr = *rp++;
png_bytep dptr = *dp++;
png_read_row(png_ptr, rptr, dptr);
}
else if (rp != NULL)
for (i = 0; i < num_rows; i++)
{
png_bytep rptr = *rp;
png_read_row(png_ptr, rptr, NULL);
rp++;
}
else if (dp != NULL)
for (i = 0; i < num_rows; i++)
{
png_bytep dptr = *dp;
png_read_row(png_ptr, NULL, dptr);
dp++;
}
} | /* Read one or more rows of image data. If the image is interlaced,
* and png_set_interlace_handling() has been called, the rows need to
* contain the contents of the rows from the previous pass. If the
* image has alpha or transparency, and png_handle_alpha()[*] has been
* called, the rows contents must be initialized to the contents of the
* screen.
*
* "row" holds the actual image, and pixels are placed in it
* as they arrive. If the image is displayed after each pass, it will
* appear to "sparkle" in. "display_row" can be used to display a
* "chunky" progressive image, with finer detail added as it becomes
* available. If you do not want this "chunky" display, you may pass
* NULL for display_row. If you do not want the sparkle display, and
* you have not called png_handle_alpha(), you may pass NULL for rows.
* If you have called png_handle_alpha(), and the image has either an
* alpha channel or a transparency chunk, you must provide a buffer for
* rows. In this case, you do not have to provide a display_row buffer
* also, but you may. If the image is not interlaced, or if you have
* not called png_set_interlace_handling(), the display_row buffer will
* be ignored, so pass NULL to it.
*
* [*] png_handle_alpha() does not exist yet, as of this version of libpng
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L567-L606 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_read_image | void PNGAPI
png_read_image(png_structrp png_ptr, png_bytepp image)
{
png_uint_32 i, image_height;
int pass, j;
png_bytepp rp;
png_debug(1, "in png_read_image");
if (png_ptr == NULL)
return;
#ifdef PNG_READ_INTERLACING_SUPPORTED
if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
{
pass = png_set_interlace_handling(png_ptr);
/* And make sure transforms are initialized. */
png_start_read_image(png_ptr);
}
else
{
if (png_ptr->interlaced && !(png_ptr->transformations & PNG_INTERLACE))
{
/* Caller called png_start_read_image or png_read_update_info without
* first turning on the PNG_INTERLACE transform. We can fix this here,
* but the caller should do it!
*/
png_warning(png_ptr, "Interlace handling should be turned on when "
"using png_read_image");
/* Make sure this is set correctly */
png_ptr->num_rows = png_ptr->height;
}
/* Obtain the pass number, which also turns on the PNG_INTERLACE flag in
* the above error case.
*/
pass = png_set_interlace_handling(png_ptr);
}
#else
if (png_ptr->interlaced)
png_error(png_ptr,
"Cannot read interlaced image -- interlace handler disabled");
pass = 1;
#endif
image_height=png_ptr->height;
for (j = 0; j < pass; j++)
{
rp = image;
for (i = 0; i < image_height; i++)
{
png_read_row(png_ptr, *rp, NULL);
rp++;
}
}
} | /* Read the entire image. If the image has an alpha channel or a tRNS
* chunk, and you have called png_handle_alpha()[*], you will need to
* initialize the image to the current image that PNG will be overlaying.
* We set the num_rows again here, in case it was incorrectly set in
* png_read_start_row() by a call to png_read_update_info() or
* png_start_read_image() if png_set_interlace_handling() wasn't called
* prior to either of these functions like it should have been. You can
* only call this function once. If you desire to have an image for
* each pass of a interlaced image, use png_read_rows() instead.
*
* [*] png_handle_alpha() does not exist yet, as of this version of libpng
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L622-L679 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_read_init | static int
png_image_read_init(png_imagep image)
{
if (image->opaque == NULL)
{
png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, image,
png_safe_error, png_safe_warning);
/* And set the rest of the structure to NULL to ensure that the various
* fields are consistent.
*/
memset(image, 0, (sizeof *image));
image->version = PNG_IMAGE_VERSION;
if (png_ptr != NULL)
{
png_infop info_ptr = png_create_info_struct(png_ptr);
if (info_ptr != NULL)
{
png_controlp control = png_voidcast(png_controlp,
png_malloc_warn(png_ptr, (sizeof *control)));
if (control != NULL)
{
memset(control, 0, (sizeof *control));
control->png_ptr = png_ptr;
control->info_ptr = info_ptr;
control->for_write = 0;
image->opaque = control;
return 1;
}
/* Error clean up */
png_destroy_info_struct(png_ptr, &info_ptr);
}
png_destroy_read_struct(&png_ptr, NULL, NULL);
}
return png_image_error(image, "png_image_read: out of memory");
}
return png_image_error(image, "png_image_read: opaque pointer not NULL");
} | /* Do all the *safe* initialization - 'safe' means that png_error won't be
* called, so setting up the jmp_buf is not required. This means that anything
* called from here must *not* call png_malloc - it has to call png_malloc_warn
* instead so that control is returned safely back to this routine.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L1173-L1219 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_format | static png_uint_32
png_image_format(png_structrp png_ptr)
{
png_uint_32 format = 0;
if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
format |= PNG_FORMAT_FLAG_COLOR;
if (png_ptr->color_type & PNG_COLOR_MASK_ALPHA)
format |= PNG_FORMAT_FLAG_ALPHA;
/* Use png_ptr here, not info_ptr, because by examination png_handle_tRNS
* sets the png_struct fields; that's all we are interested in here. The
* precise interaction with an app call to png_set_tRNS and PNG file reading
* is unclear.
*/
else if (png_ptr->num_trans > 0)
format |= PNG_FORMAT_FLAG_ALPHA;
if (png_ptr->bit_depth == 16)
format |= PNG_FORMAT_FLAG_LINEAR;
if (png_ptr->color_type & PNG_COLOR_MASK_PALETTE)
format |= PNG_FORMAT_FLAG_COLORMAP;
return format;
} | /* Utility to find the base format of a PNG file from a png_struct. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L1222-L1248 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_gamma_not_sRGB | static int
png_gamma_not_sRGB(png_fixed_point g)
{
if (g < PNG_FP_1)
{
/* An uninitialized gamma is assumed to be sRGB for the simplified API. */
if (g == 0)
return 0;
return png_gamma_significant((g * 11 + 2)/5 /* i.e. *2.2, rounded */);
}
return 1;
} | /* Is the given gamma significantly different from sRGB? The test is the same
* one used in pngrtran.c when deciding whether to do gamma correction. The
* arithmetic optimizes the division by using the fact that the inverse of the
* file sRGB gamma is 2.2
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L1255-L1268 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_read_header | static int
png_image_read_header(png_voidp argument)
{
png_imagep image = png_voidcast(png_imagep, argument);
png_structrp png_ptr = image->opaque->png_ptr;
png_inforp info_ptr = image->opaque->info_ptr;
png_set_benign_errors(png_ptr, 1/*warn*/);
png_read_info(png_ptr, info_ptr);
/* Do this the fast way; just read directly out of png_struct. */
image->width = png_ptr->width;
image->height = png_ptr->height;
{
png_uint_32 format = png_image_format(png_ptr);
image->format = format;
#ifdef PNG_COLORSPACE_SUPPORTED
/* Does the colorspace match sRGB? If there is no color endpoint
* (colorant) information assume yes, otherwise require the
* 'ENDPOINTS_MATCHE_sRGB' colorspace flag to have been set. If the
* colorspace has been determined to be invalid ignore it.
*/
if ((format & PNG_FORMAT_FLAG_COLOR) != 0 && ((png_ptr->colorspace.flags
& (PNG_COLORSPACE_HAVE_ENDPOINTS|PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB|
PNG_COLORSPACE_INVALID)) == PNG_COLORSPACE_HAVE_ENDPOINTS))
image->flags |= PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB;
#endif
}
/* We need the maximum number of entries regardless of the format the
* application sets here.
*/
{
png_uint_32 cmap_entries;
switch (png_ptr->color_type)
{
case PNG_COLOR_TYPE_GRAY:
cmap_entries = 1U << png_ptr->bit_depth;
break;
case PNG_COLOR_TYPE_PALETTE:
cmap_entries = png_ptr->num_palette;
break;
default:
cmap_entries = 256;
break;
}
if (cmap_entries > 256)
cmap_entries = 256;
image->colormap_entries = cmap_entries;
}
return 1;
} | /* Do the main body of a 'png_image_begin_read' function; read the PNG file
* header and fill in all the information. This is executed in a safe context,
* unlike the init routine above.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L1274-L1334 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_memory_read | static void PNGCBAPI
png_image_memory_read(png_structp png_ptr, png_bytep out, png_size_t need)
{
if (png_ptr != NULL)
{
png_imagep image = png_voidcast(png_imagep, png_ptr->io_ptr);
if (image != NULL)
{
png_controlp cp = image->opaque;
if (cp != NULL)
{
png_const_bytep memory = cp->memory;
png_size_t size = cp->size;
if (memory != NULL && size >= need)
{
memcpy(out, memory, need);
cp->memory = memory + need;
cp->size = size - need;
return;
}
png_error(png_ptr, "read beyond end of data");
}
}
png_error(png_ptr, "invalid memory read");
}
} | /* PNG_STDIO_SUPPORTED */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L1406-L1434 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | set_file_encoding | static void
set_file_encoding(png_image_read_control *display)
{
png_fixed_point g = display->image->opaque->png_ptr->colorspace.gamma;
if (png_gamma_significant(g))
{
if (png_gamma_not_sRGB(g))
{
display->file_encoding = E_FILE;
display->gamma_to_linear = png_reciprocal(g);
}
else
display->file_encoding = E_sRGB;
}
else
display->file_encoding = E_LINEAR8;
} | /* Utility functions to make particular color-maps */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L1524-L1542 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_create_colormap_entry | static void
png_create_colormap_entry(png_image_read_control *display,
png_uint_32 ip, png_uint_32 red, png_uint_32 green, png_uint_32 blue,
png_uint_32 alpha, int encoding)
{
png_imagep image = display->image;
const int output_encoding = (image->format & PNG_FORMAT_FLAG_LINEAR) ?
E_LINEAR : E_sRGB;
const int convert_to_Y = (image->format & PNG_FORMAT_FLAG_COLOR) == 0 &&
(red != green || green != blue);
if (ip > 255)
png_error(image->opaque->png_ptr, "color-map index out of range");
/* Update the cache with whether the file gamma is significantly different
* from sRGB.
*/
if (encoding == E_FILE)
{
if (display->file_encoding == E_NOTSET)
set_file_encoding(display);
/* Note that the cached value may be E_FILE too, but if it is then the
* gamma_to_linear member has been set.
*/
encoding = display->file_encoding;
}
if (encoding == E_FILE)
{
png_fixed_point g = display->gamma_to_linear;
red = png_gamma_16bit_correct(red*257, g);
green = png_gamma_16bit_correct(green*257, g);
blue = png_gamma_16bit_correct(blue*257, g);
if (convert_to_Y || output_encoding == E_LINEAR)
{
alpha *= 257;
encoding = E_LINEAR;
}
else
{
red = PNG_sRGB_FROM_LINEAR(red * 255);
green = PNG_sRGB_FROM_LINEAR(green * 255);
blue = PNG_sRGB_FROM_LINEAR(blue * 255);
encoding = E_sRGB;
}
}
else if (encoding == E_LINEAR8)
{
/* This encoding occurs quite frequently in test cases because PngSuite
* includes a gAMA 1.0 chunk with most images.
*/
red *= 257;
green *= 257;
blue *= 257;
alpha *= 257;
encoding = E_LINEAR;
}
else if (encoding == E_sRGB && (convert_to_Y || output_encoding == E_LINEAR))
{
/* The values are 8-bit sRGB values, but must be converted to 16-bit
* linear.
*/
red = png_sRGB_table[red];
green = png_sRGB_table[green];
blue = png_sRGB_table[blue];
alpha *= 257;
encoding = E_LINEAR;
}
/* This is set if the color isn't gray but the output is. */
if (encoding == E_LINEAR)
{
if (convert_to_Y)
{
/* NOTE: these values are copied from png_do_rgb_to_gray */
png_uint_32 y = (png_uint_32)6968 * red + (png_uint_32)23434 * green +
(png_uint_32)2366 * blue;
if (output_encoding == E_LINEAR)
y = (y + 16384) >> 15;
else
{
/* y is scaled by 32768, we need it scaled by 255: */
y = (y + 128) >> 8;
y *= 255;
y = PNG_sRGB_FROM_LINEAR((y + 64) >> 7);
encoding = E_sRGB;
}
blue = red = green = y;
}
else if (output_encoding == E_sRGB)
{
red = PNG_sRGB_FROM_LINEAR(red * 255);
green = PNG_sRGB_FROM_LINEAR(green * 255);
blue = PNG_sRGB_FROM_LINEAR(blue * 255);
alpha = PNG_DIV257(alpha);
encoding = E_sRGB;
}
}
if (encoding != output_encoding)
png_error(image->opaque->png_ptr, "bad encoding (internal error)");
/* Store the value. */
{
# ifdef PNG_FORMAT_BGR_SUPPORTED
const int afirst = (image->format & PNG_FORMAT_FLAG_AFIRST) != 0 &&
(image->format & PNG_FORMAT_FLAG_ALPHA) != 0;
# else
# define afirst 0
# endif
# ifdef PNG_FORMAT_BGR_SUPPORTED
const int bgr = (image->format & PNG_FORMAT_FLAG_BGR) ? 2 : 0;
# else
# define bgr 0
# endif
if (output_encoding == E_LINEAR)
{
png_uint_16p entry = png_voidcast(png_uint_16p, display->colormap);
entry += ip * PNG_IMAGE_SAMPLE_CHANNELS(image->format);
/* The linear 16-bit values must be pre-multiplied by the alpha channel
* value, if less than 65535 (this is, effectively, composite on black
* if the alpha channel is removed.)
*/
switch (PNG_IMAGE_SAMPLE_CHANNELS(image->format))
{
case 4:
entry[afirst ? 0 : 3] = (png_uint_16)alpha;
/* FALL THROUGH */
case 3:
if (alpha < 65535)
{
if (alpha > 0)
{
blue = (blue * alpha + 32767U)/65535U;
green = (green * alpha + 32767U)/65535U;
red = (red * alpha + 32767U)/65535U;
}
else
red = green = blue = 0;
}
entry[afirst + (2 ^ bgr)] = (png_uint_16)blue;
entry[afirst + 1] = (png_uint_16)green;
entry[afirst + bgr] = (png_uint_16)red;
break;
case 2:
entry[1 ^ afirst] = (png_uint_16)alpha;
/* FALL THROUGH */
case 1:
if (alpha < 65535)
{
if (alpha > 0)
green = (green * alpha + 32767U)/65535U;
else
green = 0;
}
entry[afirst] = (png_uint_16)green;
break;
default:
break;
}
}
else /* output encoding is E_sRGB */
{
png_bytep entry = png_voidcast(png_bytep, display->colormap);
entry += ip * PNG_IMAGE_SAMPLE_CHANNELS(image->format);
switch (PNG_IMAGE_SAMPLE_CHANNELS(image->format))
{
case 4:
entry[afirst ? 0 : 3] = (png_byte)alpha;
case 3:
entry[afirst + (2 ^ bgr)] = (png_byte)blue;
entry[afirst + 1] = (png_byte)green;
entry[afirst + bgr] = (png_byte)red;
break;
case 2:
entry[1 ^ afirst] = (png_byte)alpha;
case 1:
entry[afirst] = (png_byte)green;
break;
default:
break;
}
}
# ifdef afirst
# undef afirst
# endif
# ifdef bgr
# undef bgr
# endif
}
} | /* NOTE: E_LINEAR values to this routine must be 16-bit, but E_FILE values must
* be 8-bit.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L1619-L1834 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_read_and_map | static int
png_image_read_and_map(png_voidp argument)
{
png_image_read_control *display = png_voidcast(png_image_read_control*,
argument);
png_imagep image = display->image;
png_structrp png_ptr = image->opaque->png_ptr;
int passes;
/* Called when the libpng data must be transformed into the color-mapped
* form. There is a local row buffer in display->local and this routine must
* do the interlace handling.
*/
switch (png_ptr->interlaced)
{
case PNG_INTERLACE_NONE:
passes = 1;
break;
case PNG_INTERLACE_ADAM7:
passes = PNG_INTERLACE_ADAM7_PASSES;
break;
default:
passes = 0;
png_error(png_ptr, "unknown interlace type");
}
{
png_uint_32 height = image->height;
png_uint_32 width = image->width;
int proc = display->colormap_processing;
png_bytep first_row = png_voidcast(png_bytep, display->first_row);
ptrdiff_t step_row = display->row_bytes;
int pass;
for (pass = 0; pass < passes; ++pass)
{
unsigned int startx, stepx, stepy;
png_uint_32 y;
if (png_ptr->interlaced == PNG_INTERLACE_ADAM7)
{
/* The row may be empty for a short image: */
if (PNG_PASS_COLS(width, pass) == 0)
continue;
startx = PNG_PASS_START_COL(pass);
stepx = PNG_PASS_COL_OFFSET(pass);
y = PNG_PASS_START_ROW(pass);
stepy = PNG_PASS_ROW_OFFSET(pass);
}
else
{
y = 0;
startx = 0;
stepx = stepy = 1;
}
for (; y<height; y += stepy)
{
png_bytep inrow = png_voidcast(png_bytep, display->local_row);
png_bytep outrow = first_row + y * step_row;
png_const_bytep end_row = outrow + width;
/* Read read the libpng data into the temporary buffer. */
png_read_row(png_ptr, inrow, NULL);
/* Now process the row according to the processing option, note
* that the caller verifies that the format of the libpng output
* data is as required.
*/
outrow += startx;
switch (proc)
{
case PNG_CMAP_GA:
for (; outrow < end_row; outrow += stepx)
{
/* The data is always in the PNG order */
unsigned int gray = *inrow++;
unsigned int alpha = *inrow++;
unsigned int entry;
/* NOTE: this code is copied as a comment in
* make_ga_colormap above. Please update the
* comment if you change this code!
*/
if (alpha > 229) /* opaque */
{
entry = (231 * gray + 128) >> 8;
}
else if (alpha < 26) /* transparent */
{
entry = 231;
}
else /* partially opaque */
{
entry = 226 + 6 * PNG_DIV51(alpha) + PNG_DIV51(gray);
}
*outrow = (png_byte)entry;
}
break;
case PNG_CMAP_TRANS:
for (; outrow < end_row; outrow += stepx)
{
png_byte gray = *inrow++;
png_byte alpha = *inrow++;
if (alpha == 0)
*outrow = PNG_CMAP_TRANS_BACKGROUND;
else if (gray != PNG_CMAP_TRANS_BACKGROUND)
*outrow = gray;
else
*outrow = (png_byte)(PNG_CMAP_TRANS_BACKGROUND+1);
}
break;
case PNG_CMAP_RGB:
for (; outrow < end_row; outrow += stepx)
{
*outrow = PNG_RGB_INDEX(inrow[0], inrow[1], inrow[2]);
inrow += 3;
}
break;
case PNG_CMAP_RGB_ALPHA:
for (; outrow < end_row; outrow += stepx)
{
unsigned int alpha = inrow[3];
/* Because the alpha entries only hold alpha==0.5 values
* split the processing at alpha==0.25 (64) and 0.75
* (196).
*/
if (alpha >= 196)
*outrow = PNG_RGB_INDEX(inrow[0], inrow[1],
inrow[2]);
else if (alpha < 64)
*outrow = PNG_CMAP_RGB_ALPHA_BACKGROUND;
else
{
/* Likewise there are three entries for each of r, g
* and b. We could select the entry by popcount on
* the top two bits on those architectures that
* support it, this is what the code below does,
* crudely.
*/
unsigned int back_i = PNG_CMAP_RGB_ALPHA_BACKGROUND+1;
/* Here are how the values map:
*
* 0x00 .. 0x3f -> 0
* 0x40 .. 0xbf -> 1
* 0xc0 .. 0xff -> 2
*
* So, as above with the explicit alpha checks, the
* breakpoints are at 64 and 196.
*/
if (inrow[0] & 0x80) back_i += 9; /* red */
if (inrow[0] & 0x40) back_i += 9;
if (inrow[0] & 0x80) back_i += 3; /* green */
if (inrow[0] & 0x40) back_i += 3;
if (inrow[0] & 0x80) back_i += 1; /* blue */
if (inrow[0] & 0x40) back_i += 1;
*outrow = (png_byte)back_i;
}
inrow += 4;
}
break;
default:
break;
}
}
}
}
return 1;
} | /* The final part of the color-map read called from png_image_finish_read. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L2784-L2972 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_read_composite | static int
png_image_read_composite(png_voidp argument)
{
png_image_read_control *display = png_voidcast(png_image_read_control*,
argument);
png_imagep image = display->image;
png_structrp png_ptr = image->opaque->png_ptr;
int passes;
switch (png_ptr->interlaced)
{
case PNG_INTERLACE_NONE:
passes = 1;
break;
case PNG_INTERLACE_ADAM7:
passes = PNG_INTERLACE_ADAM7_PASSES;
break;
default:
passes = 0;
png_error(png_ptr, "unknown interlace type");
}
{
png_uint_32 height = image->height;
png_uint_32 width = image->width;
ptrdiff_t step_row = display->row_bytes;
unsigned int channels = (image->format & PNG_FORMAT_FLAG_COLOR) ? 3 : 1;
int pass;
for (pass = 0; pass < passes; ++pass)
{
unsigned int startx, stepx, stepy;
png_uint_32 y;
if (png_ptr->interlaced == PNG_INTERLACE_ADAM7)
{
/* The row may be empty for a short image: */
if (PNG_PASS_COLS(width, pass) == 0)
continue;
startx = PNG_PASS_START_COL(pass) * channels;
stepx = PNG_PASS_COL_OFFSET(pass) * channels;
y = PNG_PASS_START_ROW(pass);
stepy = PNG_PASS_ROW_OFFSET(pass);
}
else
{
y = 0;
startx = 0;
stepx = channels;
stepy = 1;
}
for (; y<height; y += stepy)
{
png_bytep inrow = png_voidcast(png_bytep, display->local_row);
png_bytep outrow;
png_const_bytep end_row;
/* Read the row, which is packed: */
png_read_row(png_ptr, inrow, NULL);
outrow = png_voidcast(png_bytep, display->first_row);
outrow += y * step_row;
end_row = outrow + width * channels;
/* Now do the composition on each pixel in this row. */
outrow += startx;
for (; outrow < end_row; outrow += stepx)
{
png_byte alpha = inrow[channels];
if (alpha > 0) /* else no change to the output */
{
unsigned int c;
for (c=0; c<channels; ++c)
{
png_uint_32 component = inrow[c];
if (alpha < 255) /* else just use component */
{
/* This is PNG_OPTIMIZED_ALPHA, the component value
* is a linear 8-bit value. Combine this with the
* current outrow[c] value which is sRGB encoded.
* Arithmetic here is 16-bits to preserve the output
* values correctly.
*/
component *= 257*255; /* =65535 */
component += (255-alpha)*png_sRGB_table[outrow[c]];
/* So 'component' is scaled by 255*65535 and is
* therefore appropriate for the sRGB to linear
* conversion table.
*/
component = PNG_sRGB_FROM_LINEAR(component);
}
outrow[c] = (png_byte)component;
}
}
inrow += channels+1; /* components and alpha channel */
}
}
}
}
return 1;
} | /* Just the row reading part of png_image_read. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L3107-L3219 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_read_background | static int
png_image_read_background(png_voidp argument)
{
png_image_read_control *display = png_voidcast(png_image_read_control*,
argument);
png_imagep image = display->image;
png_structrp png_ptr = image->opaque->png_ptr;
png_inforp info_ptr = image->opaque->info_ptr;
png_uint_32 height = image->height;
png_uint_32 width = image->width;
int pass, passes;
/* Double check the convoluted logic below. We expect to get here with
* libpng doing rgb to gray and gamma correction but background processing
* left to the png_image_read_background function. The rows libpng produce
* might be 8 or 16-bit but should always have two channels; gray plus alpha.
*/
if ((png_ptr->transformations & PNG_RGB_TO_GRAY) == 0)
png_error(png_ptr, "lost rgb to gray");
if ((png_ptr->transformations & PNG_COMPOSE) != 0)
png_error(png_ptr, "unexpected compose");
if (png_get_channels(png_ptr, info_ptr) != 2)
png_error(png_ptr, "lost/gained channels");
/* Expect the 8-bit case to always remove the alpha channel */
if ((image->format & PNG_FORMAT_FLAG_LINEAR) == 0 &&
(image->format & PNG_FORMAT_FLAG_ALPHA) != 0)
png_error(png_ptr, "unexpected 8-bit transformation");
switch (png_ptr->interlaced)
{
case PNG_INTERLACE_NONE:
passes = 1;
break;
case PNG_INTERLACE_ADAM7:
passes = PNG_INTERLACE_ADAM7_PASSES;
break;
default:
passes = 0;
png_error(png_ptr, "unknown interlace type");
}
switch (png_get_bit_depth(png_ptr, info_ptr))
{
default:
png_error(png_ptr, "unexpected bit depth");
break;
case 8:
/* 8-bit sRGB gray values with an alpha channel; the alpha channel is
* to be removed by composing on a backgroundi: either the row if
* display->background is NULL or display->background->green if not.
* Unlike the code above ALPHA_OPTIMIZED has *not* been done.
*/
{
png_bytep first_row = png_voidcast(png_bytep, display->first_row);
ptrdiff_t step_row = display->row_bytes;
for (pass = 0; pass < passes; ++pass)
{
png_bytep row = png_voidcast(png_bytep,
display->first_row);
unsigned int startx, stepx, stepy;
png_uint_32 y;
if (png_ptr->interlaced == PNG_INTERLACE_ADAM7)
{
/* The row may be empty for a short image: */
if (PNG_PASS_COLS(width, pass) == 0)
continue;
startx = PNG_PASS_START_COL(pass);
stepx = PNG_PASS_COL_OFFSET(pass);
y = PNG_PASS_START_ROW(pass);
stepy = PNG_PASS_ROW_OFFSET(pass);
}
else
{
y = 0;
startx = 0;
stepx = stepy = 1;
}
if (display->background == NULL)
{
for (; y<height; y += stepy)
{
png_bytep inrow = png_voidcast(png_bytep,
display->local_row);
png_bytep outrow = first_row + y * step_row;
png_const_bytep end_row = outrow + width;
/* Read the row, which is packed: */
png_read_row(png_ptr, inrow, NULL);
/* Now do the composition on each pixel in this row. */
outrow += startx;
for (; outrow < end_row; outrow += stepx)
{
png_byte alpha = inrow[1];
if (alpha > 0) /* else no change to the output */
{
png_uint_32 component = inrow[0];
if (alpha < 255) /* else just use component */
{
/* Since PNG_OPTIMIZED_ALPHA was not set it is
* necessary to invert the sRGB transfer
* function and multiply the alpha out.
*/
component = png_sRGB_table[component] * alpha;
component += png_sRGB_table[outrow[0]] *
(255-alpha);
component = PNG_sRGB_FROM_LINEAR(component);
}
outrow[0] = (png_byte)component;
}
inrow += 2; /* gray and alpha channel */
}
}
}
else /* constant background value */
{
png_byte background8 = display->background->green;
png_uint_16 background = png_sRGB_table[background8];
for (; y<height; y += stepy)
{
png_bytep inrow = png_voidcast(png_bytep,
display->local_row);
png_bytep outrow = first_row + y * step_row;
png_const_bytep end_row = outrow + width;
/* Read the row, which is packed: */
png_read_row(png_ptr, inrow, NULL);
/* Now do the composition on each pixel in this row. */
outrow += startx;
for (; outrow < end_row; outrow += stepx)
{
png_byte alpha = inrow[1];
if (alpha > 0) /* else use background */
{
png_uint_32 component = inrow[0];
if (alpha < 255) /* else just use component */
{
component = png_sRGB_table[component] * alpha;
component += background * (255-alpha);
component = PNG_sRGB_FROM_LINEAR(component);
}
outrow[0] = (png_byte)component;
}
else
outrow[0] = background8;
inrow += 2; /* gray and alpha channel */
}
row += display->row_bytes;
}
}
}
}
break;
case 16:
/* 16-bit linear with pre-multiplied alpha; the pre-multiplication must
* still be done and, maybe, the alpha channel removed. This code also
* handles the alpha-first option.
*/
{
png_uint_16p first_row = png_voidcast(png_uint_16p,
display->first_row);
/* The division by two is safe because the caller passed in a
* stride which was multiplied by 2 (below) to get row_bytes.
*/
ptrdiff_t step_row = display->row_bytes / 2;
int preserve_alpha = (image->format & PNG_FORMAT_FLAG_ALPHA) != 0;
unsigned int outchannels = 1+preserve_alpha;
int swap_alpha = 0;
if (preserve_alpha && (image->format & PNG_FORMAT_FLAG_AFIRST))
swap_alpha = 1;
for (pass = 0; pass < passes; ++pass)
{
unsigned int startx, stepx, stepy;
png_uint_32 y;
/* The 'x' start and step are adjusted to output components here.
*/
if (png_ptr->interlaced == PNG_INTERLACE_ADAM7)
{
/* The row may be empty for a short image: */
if (PNG_PASS_COLS(width, pass) == 0)
continue;
startx = PNG_PASS_START_COL(pass) * outchannels;
stepx = PNG_PASS_COL_OFFSET(pass) * outchannels;
y = PNG_PASS_START_ROW(pass);
stepy = PNG_PASS_ROW_OFFSET(pass);
}
else
{
y = 0;
startx = 0;
stepx = outchannels;
stepy = 1;
}
for (; y<height; y += stepy)
{
png_const_uint_16p inrow;
png_uint_16p outrow = first_row + y*step_row;
png_uint_16p end_row = outrow + width * outchannels;
/* Read the row, which is packed: */
png_read_row(png_ptr, png_voidcast(png_bytep,
display->local_row), NULL);
inrow = png_voidcast(png_const_uint_16p, display->local_row);
/* Now do the pre-multiplication on each pixel in this row.
*/
outrow += startx;
for (; outrow < end_row; outrow += stepx)
{
png_uint_32 component = inrow[0];
png_uint_16 alpha = inrow[1];
if (alpha > 0) /* else 0 */
{
if (alpha < 65535) /* else just use component */
{
component *= alpha;
component += 32767;
component /= 65535;
}
}
else
component = 0;
outrow[swap_alpha] = (png_uint_16)component;
if (preserve_alpha)
outrow[1 ^ swap_alpha] = alpha;
inrow += 2; /* components and alpha channel */
}
}
}
}
break;
}
return 1;
} | /* The do_local_background case; called when all the following transforms are to
* be done:
*
* PNG_RGB_TO_GRAY
* PNG_COMPOSITE
* PNG_GAMMA
*
* This is a work-round for the fact that both the PNG_RGB_TO_GRAY and
* PNG_COMPOSITE code performs gamma correction, so we get double gamma
* correction. The fix-up is to prevent the PNG_COMPOSITE operation happening
* inside libpng, so this routine sees an 8 or 16-bit gray+alpha row and handles
* the removal or pre-multiplication of the alpha channel.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L3234-L3503 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_image_read_direct | static int
png_image_read_direct(png_voidp argument)
{
png_image_read_control *display = png_voidcast(png_image_read_control*,
argument);
png_imagep image = display->image;
png_structrp png_ptr = image->opaque->png_ptr;
png_inforp info_ptr = image->opaque->info_ptr;
png_uint_32 format = image->format;
int linear = (format & PNG_FORMAT_FLAG_LINEAR) != 0;
int do_local_compose = 0;
int do_local_background = 0; /* to avoid double gamma correction bug */
int passes = 0;
/* Add transforms to ensure the correct output format is produced then check
* that the required implementation support is there. Always expand; always
* need 8 bits minimum, no palette and expanded tRNS.
*/
png_set_expand(png_ptr);
/* Now check the format to see if it was modified. */
{
png_uint_32 base_format = png_image_format(png_ptr) &
~PNG_FORMAT_FLAG_COLORMAP /* removed by png_set_expand */;
png_uint_32 change = format ^ base_format;
png_fixed_point output_gamma;
int mode; /* alpha mode */
/* Do this first so that we have a record if rgb to gray is happening. */
if (change & PNG_FORMAT_FLAG_COLOR)
{
/* gray<->color transformation required. */
if (format & PNG_FORMAT_FLAG_COLOR)
png_set_gray_to_rgb(png_ptr);
else
{
/* libpng can't do both rgb to gray and
* background/pre-multiplication if there is also significant gamma
* correction, because both operations require linear colors and
* the code only supports one transform doing the gamma correction.
* Handle this by doing the pre-multiplication or background
* operation in this code, if necessary.
*
* TODO: fix this by rewriting pngrtran.c (!)
*
* For the moment (given that fixing this in pngrtran.c is an
* enormous change) 'do_local_background' is used to indicate that
* the problem exists.
*/
if (base_format & PNG_FORMAT_FLAG_ALPHA)
do_local_background = 1/*maybe*/;
png_set_rgb_to_gray_fixed(png_ptr, PNG_ERROR_ACTION_NONE,
PNG_RGB_TO_GRAY_DEFAULT, PNG_RGB_TO_GRAY_DEFAULT);
}
change &= ~PNG_FORMAT_FLAG_COLOR;
}
/* Set the gamma appropriately, linear for 16-bit input, sRGB otherwise.
*/
{
png_fixed_point input_gamma_default;
if ((base_format & PNG_FORMAT_FLAG_LINEAR) &&
(image->flags & PNG_IMAGE_FLAG_16BIT_sRGB) == 0)
input_gamma_default = PNG_GAMMA_LINEAR;
else
input_gamma_default = PNG_DEFAULT_sRGB;
/* Call png_set_alpha_mode to set the default for the input gamma; the
* output gamma is set by a second call below.
*/
png_set_alpha_mode_fixed(png_ptr, PNG_ALPHA_PNG, input_gamma_default);
}
if (linear)
{
/* If there *is* an alpha channel in the input it must be multiplied
* out; use PNG_ALPHA_STANDARD, otherwise just use PNG_ALPHA_PNG.
*/
if (base_format & PNG_FORMAT_FLAG_ALPHA)
mode = PNG_ALPHA_STANDARD; /* associated alpha */
else
mode = PNG_ALPHA_PNG;
output_gamma = PNG_GAMMA_LINEAR;
}
else
{
mode = PNG_ALPHA_PNG;
output_gamma = PNG_DEFAULT_sRGB;
}
/* If 'do_local_background' is set check for the presence of gamma
* correction; this is part of the work-round for the libpng bug
* described above.
*
* TODO: fix libpng and remove this.
*/
if (do_local_background)
{
png_fixed_point gtest;
/* This is 'png_gamma_threshold' from pngrtran.c; the test used for
* gamma correction, the screen gamma hasn't been set on png_struct
* yet; it's set below. png_struct::gamma, however, is set to the
* final value.
*/
if (png_muldiv(>est, output_gamma, png_ptr->colorspace.gamma,
PNG_FP_1) && !png_gamma_significant(gtest))
do_local_background = 0;
else if (mode == PNG_ALPHA_STANDARD)
{
do_local_background = 2/*required*/;
mode = PNG_ALPHA_PNG; /* prevent libpng doing it */
}
/* else leave as 1 for the checks below */
}
/* If the bit-depth changes then handle that here. */
if (change & PNG_FORMAT_FLAG_LINEAR)
{
if (linear /*16-bit output*/)
png_set_expand_16(png_ptr);
else /* 8-bit output */
png_set_scale_16(png_ptr);
change &= ~PNG_FORMAT_FLAG_LINEAR;
}
/* Now the background/alpha channel changes. */
if (change & PNG_FORMAT_FLAG_ALPHA)
{
/* Removing an alpha channel requires composition for the 8-bit
* formats; for the 16-bit it is already done, above, by the
* pre-multiplication and the channel just needs to be stripped.
*/
if (base_format & PNG_FORMAT_FLAG_ALPHA)
{
/* If RGB->gray is happening the alpha channel must be left and the
* operation completed locally.
*
* TODO: fix libpng and remove this.
*/
if (do_local_background)
do_local_background = 2/*required*/;
/* 16-bit output: just remove the channel */
else if (linear) /* compose on black (well, pre-multiply) */
png_set_strip_alpha(png_ptr);
/* 8-bit output: do an appropriate compose */
else if (display->background != NULL)
{
png_color_16 c;
c.index = 0; /*unused*/
c.red = display->background->red;
c.green = display->background->green;
c.blue = display->background->blue;
c.gray = display->background->green;
/* This is always an 8-bit sRGB value, using the 'green' channel
* for gray is much better than calculating the luminance here;
* we can get off-by-one errors in that calculation relative to
* the app expectations and that will show up in transparent
* pixels.
*/
png_set_background_fixed(png_ptr, &c,
PNG_BACKGROUND_GAMMA_SCREEN, 0/*need_expand*/,
0/*gamma: not used*/);
}
else /* compose on row: implemented below. */
{
do_local_compose = 1;
/* This leaves the alpha channel in the output, so it has to be
* removed by the code below. Set the encoding to the 'OPTIMIZE'
* one so the code only has to hack on the pixels that require
* composition.
*/
mode = PNG_ALPHA_OPTIMIZED;
}
}
else /* output needs an alpha channel */
{
/* This is tricky because it happens before the swap operation has
* been accomplished; however, the swap does *not* swap the added
* alpha channel (weird API), so it must be added in the correct
* place.
*/
png_uint_32 filler; /* opaque filler */
int where;
if (linear)
filler = 65535;
else
filler = 255;
# ifdef PNG_FORMAT_AFIRST_SUPPORTED
if (format & PNG_FORMAT_FLAG_AFIRST)
{
where = PNG_FILLER_BEFORE;
change &= ~PNG_FORMAT_FLAG_AFIRST;
}
else
# endif
where = PNG_FILLER_AFTER;
png_set_add_alpha(png_ptr, filler, where);
}
/* This stops the (irrelevant) call to swap_alpha below. */
change &= ~PNG_FORMAT_FLAG_ALPHA;
}
/* Now set the alpha mode correctly; this is always done, even if there is
* no alpha channel in either the input or the output because it correctly
* sets the output gamma.
*/
png_set_alpha_mode_fixed(png_ptr, mode, output_gamma);
# ifdef PNG_FORMAT_BGR_SUPPORTED
if (change & PNG_FORMAT_FLAG_BGR)
{
/* Check only the output format; PNG is never BGR; don't do this if
* the output is gray, but fix up the 'format' value in that case.
*/
if (format & PNG_FORMAT_FLAG_COLOR)
png_set_bgr(png_ptr);
else
format &= ~PNG_FORMAT_FLAG_BGR;
change &= ~PNG_FORMAT_FLAG_BGR;
}
# endif
# ifdef PNG_FORMAT_AFIRST_SUPPORTED
if (change & PNG_FORMAT_FLAG_AFIRST)
{
/* Only relevant if there is an alpha channel - it's particularly
* important to handle this correctly because do_local_compose may
* be set above and then libpng will keep the alpha channel for this
* code to remove.
*/
if (format & PNG_FORMAT_FLAG_ALPHA)
{
/* Disable this if doing a local background,
* TODO: remove this when local background is no longer required.
*/
if (do_local_background != 2)
png_set_swap_alpha(png_ptr);
}
else
format &= ~PNG_FORMAT_FLAG_AFIRST;
change &= ~PNG_FORMAT_FLAG_AFIRST;
}
# endif
/* If the *output* is 16-bit then we need to check for a byte-swap on this
* architecture.
*/
if (linear)
{
PNG_CONST png_uint_16 le = 0x0001;
if (*(png_const_bytep)&le)
png_set_swap(png_ptr);
}
/* If change is not now 0 some transformation is missing - error out. */
if (change)
png_error(png_ptr, "png_read_image: unsupported transformation");
}
PNG_SKIP_CHUNKS(png_ptr);
/* Update the 'info' structure and make sure the result is as required; first
* make sure to turn on the interlace handling if it will be required
* (because it can't be turned on *after* the call to png_read_update_info!)
*
* TODO: remove the do_local_background fixup below.
*/
if (!do_local_compose && do_local_background != 2)
passes = png_set_interlace_handling(png_ptr);
png_read_update_info(png_ptr, info_ptr);
{
png_uint_32 info_format = 0;
if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
info_format |= PNG_FORMAT_FLAG_COLOR;
if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
{
/* do_local_compose removes this channel below. */
if (!do_local_compose)
{
/* do_local_background does the same if required. */
if (do_local_background != 2 ||
(format & PNG_FORMAT_FLAG_ALPHA) != 0)
info_format |= PNG_FORMAT_FLAG_ALPHA;
}
}
else if (do_local_compose) /* internal error */
png_error(png_ptr, "png_image_read: alpha channel lost");
if (info_ptr->bit_depth == 16)
info_format |= PNG_FORMAT_FLAG_LINEAR;
# ifdef PNG_FORMAT_BGR_SUPPORTED
if (png_ptr->transformations & PNG_BGR)
info_format |= PNG_FORMAT_FLAG_BGR;
# endif
# ifdef PNG_FORMAT_AFIRST_SUPPORTED
if (do_local_background == 2)
{
if (format & PNG_FORMAT_FLAG_AFIRST)
info_format |= PNG_FORMAT_FLAG_AFIRST;
}
if ((png_ptr->transformations & PNG_SWAP_ALPHA) != 0 ||
((png_ptr->transformations & PNG_ADD_ALPHA) != 0 &&
(png_ptr->flags & PNG_FLAG_FILLER_AFTER) == 0))
{
if (do_local_background == 2)
png_error(png_ptr, "unexpected alpha swap transformation");
info_format |= PNG_FORMAT_FLAG_AFIRST;
}
# endif
/* This is actually an internal error. */
if (info_format != format)
png_error(png_ptr, "png_read_image: invalid transformations");
}
/* Now read the rows. If do_local_compose is set then it is necessary to use
* a local row buffer. The output will be GA, RGBA or BGRA and must be
* converted to G, RGB or BGR as appropriate. The 'local_row' member of the
* display acts as a flag.
*/
{
png_voidp first_row = display->buffer;
ptrdiff_t row_bytes = display->row_stride;
if (linear)
row_bytes *= 2;
/* The following expression is designed to work correctly whether it gives
* a signed or an unsigned result.
*/
if (row_bytes < 0)
{
char *ptr = png_voidcast(char*, first_row);
ptr += (image->height-1) * (-row_bytes);
first_row = png_voidcast(png_voidp, ptr);
}
display->first_row = first_row;
display->row_bytes = row_bytes;
}
if (do_local_compose)
{
int result;
png_voidp row = png_malloc(png_ptr, png_get_rowbytes(png_ptr, info_ptr));
display->local_row = row;
result = png_safe_execute(image, png_image_read_composite, display);
display->local_row = NULL;
png_free(png_ptr, row);
return result;
}
else if (do_local_background == 2)
{
int result;
png_voidp row = png_malloc(png_ptr, png_get_rowbytes(png_ptr, info_ptr));
display->local_row = row;
result = png_safe_execute(image, png_image_read_background, display);
display->local_row = NULL;
png_free(png_ptr, row);
return result;
}
else
{
png_alloc_size_t row_bytes = display->row_bytes;
while (--passes >= 0)
{
png_uint_32 y = image->height;
png_bytep row = png_voidcast(png_bytep, display->first_row);
while (y-- > 0)
{
png_read_row(png_ptr, row, NULL);
row += row_bytes;
}
}
return 1;
}
} | /* The guts of png_image_finish_read as a png_safe_execute callback. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngread.c#L3506-L3930 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_read_data | void /* PRIVATE */
png_read_data(png_structrp png_ptr, png_bytep data, png_size_t length)
{
png_debug1(4, "reading %d bytes", (int)length);
if (png_ptr->read_data_fn != NULL)
(*(png_ptr->read_data_fn))(png_ptr, data, length);
else
png_error(png_ptr, "Call to NULL read function");
} | /* Read the data from whatever input you are using. The default routine
* reads from a file pointer. Note that this routine sometimes gets called
* with very small lengths, so you should implement some kind of simple
* buffering if you are using unbuffered reads. This should never be asked
* to read more then 64K on a 16 bit machine.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrio.c#L31-L41 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_default_read_data | void PNGCBAPI
png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
png_size_t check;
if (png_ptr == NULL)
return;
/* fread() returns 0 on error, so it is OK to store this in a png_size_t
* instead of an int, which is what fread() actually returns.
*/
check = fread(data, 1, length, png_voidcast(png_FILE_p, png_ptr->io_ptr));
if (check != length)
png_error(png_ptr, "Read Error");
} | /* This is the function that does the actual reading of data. If you are
* not reading from a standard C stream, you should create a replacement
* read_data function and use it at run time with png_set_read_fn(), rather
* than changing the library.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrio.c#L49-L64 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_read_fn | void PNGAPI
png_set_read_fn(png_structrp png_ptr, png_voidp io_ptr,
png_rw_ptr read_data_fn)
{
if (png_ptr == NULL)
return;
png_ptr->io_ptr = io_ptr;
#ifdef PNG_STDIO_SUPPORTED
if (read_data_fn != NULL)
png_ptr->read_data_fn = read_data_fn;
else
png_ptr->read_data_fn = png_default_read_data;
#else
png_ptr->read_data_fn = read_data_fn;
#endif
/* It is an error to write to a read device */
if (png_ptr->write_data_fn != NULL)
{
png_ptr->write_data_fn = NULL;
png_warning(png_ptr,
"Can't set both read_data_fn and write_data_fn in the"
" same structure");
}
#ifdef PNG_WRITE_FLUSH_SUPPORTED
png_ptr->output_flush_fn = NULL;
#endif
} | /* This function allows the application to supply a new input function
* for libpng if standard C streams aren't being used.
*
* This function takes as its arguments:
*
* png_ptr - pointer to a png input data structure
*
* io_ptr - pointer to user supplied structure containing info about
* the input functions. May be NULL.
*
* read_data_fn - pointer to a new input function that takes as its
* arguments a pointer to a png_struct, a pointer to
* a location where input data can be stored, and a 32-bit
* unsigned int that is the number of bytes to be read.
* To exit and output any fatal error messages the new write
* function should call png_error(png_ptr, "Error msg").
* May be NULL, in which case libpng's default function will
* be used.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrio.c#L86-L117 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_crc_action | void PNGAPI
png_set_crc_action(png_structrp png_ptr, int crit_action, int ancil_action)
{
png_debug(1, "in png_set_crc_action");
if (png_ptr == NULL)
return;
/* Tell libpng how we react to CRC errors in critical chunks */
switch (crit_action)
{
case PNG_CRC_NO_CHANGE: /* Leave setting as is */
break;
case PNG_CRC_WARN_USE: /* Warn/use data */
png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE;
break;
case PNG_CRC_QUIET_USE: /* Quiet/use data */
png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE |
PNG_FLAG_CRC_CRITICAL_IGNORE;
break;
case PNG_CRC_WARN_DISCARD: /* Not a valid action for critical data */
png_warning(png_ptr,
"Can't discard critical data on CRC error");
case PNG_CRC_ERROR_QUIT: /* Error/quit */
case PNG_CRC_DEFAULT:
default:
png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
break;
}
/* Tell libpng how we react to CRC errors in ancillary chunks */
switch (ancil_action)
{
case PNG_CRC_NO_CHANGE: /* Leave setting as is */
break;
case PNG_CRC_WARN_USE: /* Warn/use data */
png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE;
break;
case PNG_CRC_QUIET_USE: /* Quiet/use data */
png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE |
PNG_FLAG_CRC_ANCILLARY_NOWARN;
break;
case PNG_CRC_ERROR_QUIT: /* Error/quit */
png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_NOWARN;
break;
case PNG_CRC_WARN_DISCARD: /* Warn/discard data */
case PNG_CRC_DEFAULT:
default:
png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
break;
}
} | /* Set the action on getting a CRC error for an ancillary or critical chunk. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L24-L89 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_rtran_ok | static int
png_rtran_ok(png_structrp png_ptr, int need_IHDR)
{
if (png_ptr != NULL)
{
if (png_ptr->flags & PNG_FLAG_ROW_INIT)
png_app_error(png_ptr,
"invalid after png_start_read_image or png_read_update_info");
else if (need_IHDR && (png_ptr->mode & PNG_HAVE_IHDR) == 0)
png_app_error(png_ptr, "invalid before the PNG header has been read");
else
{
/* Turn on failure to initialize correctly for all transforms. */
png_ptr->flags |= PNG_FLAG_DETECT_UNINITIALIZED;
return 1; /* Ok */
}
}
return 0; /* no png_error possible! */
} | /* Is it OK to set a transformation now? Only if png_start_read_image or
* png_read_update_info have not been called. It is not necessary for the IHDR
* to have been read in all cases, the parameter allows for this check too.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L96-L118 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_background_fixed | void PNGFAPI
png_set_background_fixed(png_structrp png_ptr,
png_const_color_16p background_color, int background_gamma_code,
int need_expand, png_fixed_point background_gamma)
{
png_debug(1, "in png_set_background_fixed");
if (!png_rtran_ok(png_ptr, 0) || background_color == NULL)
return;
if (background_gamma_code == PNG_BACKGROUND_GAMMA_UNKNOWN)
{
png_warning(png_ptr, "Application must supply a known background gamma");
return;
}
png_ptr->transformations |= PNG_COMPOSE | PNG_STRIP_ALPHA;
png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
png_ptr->background = *background_color;
png_ptr->background_gamma = background_gamma;
png_ptr->background_gamma_type = (png_byte)(background_gamma_code);
if (need_expand)
png_ptr->transformations |= PNG_BACKGROUND_EXPAND;
else
png_ptr->transformations &= ~PNG_BACKGROUND_EXPAND;
} | /* Handle alpha and tRNS via a background color */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L123-L150 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_strip_16 | void PNGAPI
png_set_strip_16(png_structrp png_ptr)
{
png_debug(1, "in png_set_strip_16");
if (!png_rtran_ok(png_ptr, 0))
return;
png_ptr->transformations |= PNG_16_TO_8;
} | /* Chop 16-bit depth files to 8-bit depth */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L183-L192 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_expand | void PNGAPI
png_set_expand(png_structrp png_ptr)
{
png_debug(1, "in png_set_expand");
if (!png_rtran_ok(png_ptr, 0))
return;
png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
} | /* Expand paletted images to RGB, expand grayscale images of
* less than 8-bit depth to 8-bit depth, and expand tRNS chunks
* to alpha channels.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L853-L862 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_palette_to_rgb | void PNGAPI
png_set_palette_to_rgb(png_structrp png_ptr)
{
png_debug(1, "in png_set_palette_to_rgb");
if (!png_rtran_ok(png_ptr, 0))
return;
png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
} | /* GRR 19990627: the following three functions currently are identical
* to png_set_expand(). However, it is entirely reasonable that someone
* might wish to expand an indexed image to RGB but *not* expand a single,
* fully transparent palette entry to a full alpha channel--perhaps instead
* convert tRNS to the grayscale/RGB format (16-bit RGB value), or replace
* the transparent color with a particular RGB value, or drop tRNS entirely.
* IOW, a future version of the library may make the transformations flag
* a bit more fine-grained, with separate bits for each of these three
* functions.
*
* More to the point, these functions make it obvious what libpng will be
* doing, whereas "expand" can (and does) mean any number of things.
*
* GRP 20060307: In libpng-1.2.9, png_set_gray_1_2_4_to_8() was modified
* to expand only the sample depth but not to expand the tRNS to alpha
* and its name was changed to png_set_expand_gray_1_2_4_to_8().
*/
/* Expand paletted images to RGB. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L883-L892 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_gray_1_2_4_to_8 | void PNGAPI
png_set_gray_1_2_4_to_8(png_structrp png_ptr)
{
png_set_expand_gray_1_2_4_to_8(png_ptr);
} | /* Obsolete function call */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L895-L899 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_expand_gray_1_2_4_to_8 | void PNGAPI
png_set_expand_gray_1_2_4_to_8(png_structrp png_ptr)
{
png_debug(1, "in png_set_expand_gray_1_2_4_to_8");
if (!png_rtran_ok(png_ptr, 0))
return;
png_ptr->transformations |= PNG_EXPAND;
} | /* Expand grayscale images of less than 8-bit depth to 8 bits. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L903-L912 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_tRNS_to_alpha | void PNGAPI
png_set_tRNS_to_alpha(png_structrp png_ptr)
{
png_debug(1, "in png_set_tRNS_to_alpha");
if (!png_rtran_ok(png_ptr, 0))
return;
png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
} | /* Expand tRNS chunks to alpha channels. */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L915-L924 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_expand_16 | void PNGAPI
png_set_expand_16(png_structrp png_ptr)
{
png_debug(1, "in png_set_expand_16");
if (!png_rtran_ok(png_ptr, 0))
return;
png_ptr->transformations |= (PNG_EXPAND_16 | PNG_EXPAND | PNG_EXPAND_tRNS);
} | /* Expand to 16-bit channels, expand the tRNS chunk too (because otherwise
* it may not work correctly.)
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L931-L940 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_set_rgb_to_gray | void PNGAPI
png_set_rgb_to_gray(png_structrp png_ptr, int error_action, double red,
double green)
{
png_set_rgb_to_gray_fixed(png_ptr, error_action,
png_fixed(png_ptr, red, "rgb to gray red coefficient"),
png_fixed(png_ptr, green, "rgb to gray green coefficient"));
} | /* Convert a RGB image to a grayscale of the same width. This allows us,
* for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L1049-L1056 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_gamma_threshold | static int /* PRIVATE */
png_gamma_threshold(png_fixed_point screen_gamma, png_fixed_point file_gamma)
{
/* PNG_GAMMA_THRESHOLD is the threshold for performing gamma
* correction as a difference of the overall transform from 1.0
*
* We want to compare the threshold with s*f - 1, if we get
* overflow here it is because of wacky gamma values so we
* turn on processing anyway.
*/
png_fixed_point gtest;
return !png_muldiv(>est, screen_gamma, file_gamma, PNG_FP_1) ||
png_gamma_significant(gtest);
} | /* In the case of gamma transformations only do transformations on images where
* the [file] gamma and screen_gamma are not close reciprocals, otherwise it
* slows things down slightly, and also needlessly introduces small errors.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L1082-L1095 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_init_palette_transformations | static void /* PRIVATE */
png_init_palette_transformations(png_structrp png_ptr)
{
/* Called to handle the (input) palette case. In png_do_read_transformations
* the first step is to expand the palette if requested, so this code must
* take care to only make changes that are invariant with respect to the
* palette expansion, or only do them if there is no expansion.
*
* STRIP_ALPHA has already been handled in the caller (by setting num_trans
* to 0.)
*/
int input_has_alpha = 0;
int input_has_transparency = 0;
if (png_ptr->num_trans > 0)
{
int i;
/* Ignore if all the entries are opaque (unlikely!) */
for (i=0; i<png_ptr->num_trans; ++i)
if (png_ptr->trans_alpha[i] == 255)
continue;
else if (png_ptr->trans_alpha[i] == 0)
input_has_transparency = 1;
else
input_has_alpha = 1;
}
/* If no alpha we can optimize. */
if (!input_has_alpha)
{
/* Any alpha means background and associative alpha processing is
* required, however if the alpha is 0 or 1 throughout OPTIIMIZE_ALPHA
* and ENCODE_ALPHA are irrelevant.
*/
png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
if (!input_has_transparency)
png_ptr->transformations &= ~(PNG_COMPOSE | PNG_BACKGROUND_EXPAND);
}
#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
/* png_set_background handling - deals with the complexity of whether the
* background color is in the file format or the screen format in the case
* where an 'expand' will happen.
*/
/* The following code cannot be entered in the alpha pre-multiplication case
* because PNG_BACKGROUND_EXPAND is cancelled below.
*/
if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
(png_ptr->transformations & PNG_EXPAND))
{
{
png_ptr->background.red =
png_ptr->palette[png_ptr->background.index].red;
png_ptr->background.green =
png_ptr->palette[png_ptr->background.index].green;
png_ptr->background.blue =
png_ptr->palette[png_ptr->background.index].blue;
#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
if (png_ptr->transformations & PNG_INVERT_ALPHA)
{
if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
{
/* Invert the alpha channel (in tRNS) unless the pixels are
* going to be expanded, in which case leave it for later
*/
int i, istop = png_ptr->num_trans;
for (i=0; i<istop; i++)
png_ptr->trans_alpha[i] = (png_byte)(255 -
png_ptr->trans_alpha[i]);
}
}
#endif /* PNG_READ_INVERT_ALPHA_SUPPORTED */
}
} /* background expand and (therefore) no alpha association. */
#endif /* PNG_READ_EXPAND_SUPPORTED && PNG_READ_BACKGROUND_SUPPORTED */
} | /* Initialize everything needed for the read. This includes modifying
* the palette.
*/
/*For the moment 'png_init_palette_transformations' and
* 'png_init_rgb_transformations' only do some flag canceling optimizations.
* The intent is that these two routines should have palette or rgb operations
* extracted from 'png_init_read_transformations'.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L1107-L1188 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_read_transform_info | void /* PRIVATE */
png_read_transform_info(png_structrp png_ptr, png_inforp info_ptr)
{
png_debug(1, "in png_read_transform_info");
#ifdef PNG_READ_EXPAND_SUPPORTED
if (png_ptr->transformations & PNG_EXPAND)
{
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
/* This check must match what actually happens in
* png_do_expand_palette; if it ever checks the tRNS chunk to see if
* it is all opaque we must do the same (at present it does not.)
*/
if (png_ptr->num_trans > 0)
info_ptr->color_type = PNG_COLOR_TYPE_RGB_ALPHA;
else
info_ptr->color_type = PNG_COLOR_TYPE_RGB;
info_ptr->bit_depth = 8;
info_ptr->num_trans = 0;
}
else
{
if (png_ptr->num_trans)
{
if (png_ptr->transformations & PNG_EXPAND_tRNS)
info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
}
if (info_ptr->bit_depth < 8)
info_ptr->bit_depth = 8;
info_ptr->num_trans = 0;
}
}
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
defined(PNG_READ_ALPHA_MODE_SUPPORTED)
/* The following is almost certainly wrong unless the background value is in
* the screen space!
*/
if (png_ptr->transformations & PNG_COMPOSE)
info_ptr->background = png_ptr->background;
#endif
#ifdef PNG_READ_GAMMA_SUPPORTED
/* The following used to be conditional on PNG_GAMMA (prior to 1.5.4),
* however it seems that the code in png_init_read_transformations, which has
* been called before this from png_read_update_info->png_read_start_row
* sometimes does the gamma transform and cancels the flag.
*
* TODO: this looks wrong; the info_ptr should end up with a gamma equal to
* the screen_gamma value. The following probably results in weirdness if
* the info_ptr is used by the app after the rows have been read.
*/
info_ptr->colorspace.gamma = png_ptr->colorspace.gamma;
#endif
if (info_ptr->bit_depth == 16)
{
# ifdef PNG_READ_16BIT_SUPPORTED
# ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
if (png_ptr->transformations & PNG_SCALE_16_TO_8)
info_ptr->bit_depth = 8;
# endif
# ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
if (png_ptr->transformations & PNG_16_TO_8)
info_ptr->bit_depth = 8;
# endif
# else
/* No 16 bit support: force chopping 16-bit input down to 8, in this case
* the app program can chose if both APIs are available by setting the
* correct scaling to use.
*/
# ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
/* For compatibility with previous versions use the strip method by
* default. This code works because if PNG_SCALE_16_TO_8 is already
* set the code below will do that in preference to the chop.
*/
png_ptr->transformations |= PNG_16_TO_8;
info_ptr->bit_depth = 8;
# else
# ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
png_ptr->transformations |= PNG_SCALE_16_TO_8;
info_ptr->bit_depth = 8;
# else
CONFIGURATION ERROR: you must enable at least one 16 to 8 method
# endif
# endif
#endif /* !READ_16BIT_SUPPORTED */
}
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
if (png_ptr->transformations & PNG_GRAY_TO_RGB)
info_ptr->color_type = (png_byte)(info_ptr->color_type |
PNG_COLOR_MASK_COLOR);
#endif
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
if (png_ptr->transformations & PNG_RGB_TO_GRAY)
info_ptr->color_type = (png_byte)(info_ptr->color_type &
~PNG_COLOR_MASK_COLOR);
#endif
#ifdef PNG_READ_QUANTIZE_SUPPORTED
if (png_ptr->transformations & PNG_QUANTIZE)
{
if (((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
(info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) &&
png_ptr->palette_lookup && info_ptr->bit_depth == 8)
{
info_ptr->color_type = PNG_COLOR_TYPE_PALETTE;
}
}
#endif
#ifdef PNG_READ_EXPAND_16_SUPPORTED
if (png_ptr->transformations & PNG_EXPAND_16 && info_ptr->bit_depth == 8 &&
info_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
{
info_ptr->bit_depth = 16;
}
#endif
#ifdef PNG_READ_PACK_SUPPORTED
if ((png_ptr->transformations & PNG_PACK) && (info_ptr->bit_depth < 8))
info_ptr->bit_depth = 8;
#endif
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
info_ptr->channels = 1;
else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
info_ptr->channels = 3;
else
info_ptr->channels = 1;
#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
if (png_ptr->transformations & PNG_STRIP_ALPHA)
{
info_ptr->color_type = (png_byte)(info_ptr->color_type &
~PNG_COLOR_MASK_ALPHA);
info_ptr->num_trans = 0;
}
#endif
if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
info_ptr->channels++;
#ifdef PNG_READ_FILLER_SUPPORTED
/* STRIP_ALPHA and FILLER allowed: MASK_ALPHA bit stripped above */
if ((png_ptr->transformations & PNG_FILLER) &&
((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
(info_ptr->color_type == PNG_COLOR_TYPE_GRAY)))
{
info_ptr->channels++;
/* If adding a true alpha channel not just filler */
if (png_ptr->transformations & PNG_ADD_ALPHA)
info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
}
#endif
#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) && \
defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
if (png_ptr->transformations & PNG_USER_TRANSFORM)
{
if (info_ptr->bit_depth < png_ptr->user_transform_depth)
info_ptr->bit_depth = png_ptr->user_transform_depth;
if (info_ptr->channels < png_ptr->user_transform_channels)
info_ptr->channels = png_ptr->user_transform_channels;
}
#endif
info_ptr->pixel_depth = (png_byte)(info_ptr->channels *
info_ptr->bit_depth);
info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, info_ptr->width);
/* Adding in 1.5.4: cache the above value in png_struct so that we can later
* check in png_rowbytes that the user buffer won't get overwritten. Note
* that the field is not always set - if png_read_update_info isn't called
* the application has to either not do any transforms or get the calculation
* right itself.
*/
png_ptr->info_rowbytes = info_ptr->rowbytes;
#ifndef PNG_READ_EXPAND_SUPPORTED
if (png_ptr)
return;
#endif
} | /* Modify the info structure to reflect the transformations. The
* info should be updated so a PNG file could be written with it,
* assuming the transformations result in valid PNG data.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L1922-L2120 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_do_read_transformations | void /* PRIVATE */
png_do_read_transformations(png_structrp png_ptr, png_row_infop row_info)
{
png_debug(1, "in png_do_read_transformations");
if (png_ptr->row_buf == NULL)
{
/* Prior to 1.5.4 this output row/pass where the NULL pointer is, but this
* error is incredibly rare and incredibly easy to debug without this
* information.
*/
png_error(png_ptr, "NULL row buffer");
}
/* The following is debugging; prior to 1.5.4 the code was never compiled in;
* in 1.5.4 PNG_FLAG_DETECT_UNINITIALIZED was added and the macro
* PNG_WARN_UNINITIALIZED_ROW removed. In 1.6 the new flag is set only for
* all transformations, however in practice the ROW_INIT always gets done on
* demand, if necessary.
*/
if ((png_ptr->flags & PNG_FLAG_DETECT_UNINITIALIZED) != 0 &&
!(png_ptr->flags & PNG_FLAG_ROW_INIT))
{
/* Application has failed to call either png_read_start_image() or
* png_read_update_info() after setting transforms that expand pixels.
* This check added to libpng-1.2.19 (but not enabled until 1.5.4).
*/
png_error(png_ptr, "Uninitialized row");
}
#ifdef PNG_READ_EXPAND_SUPPORTED
if (png_ptr->transformations & PNG_EXPAND)
{
if (row_info->color_type == PNG_COLOR_TYPE_PALETTE)
{
png_do_expand_palette(row_info, png_ptr->row_buf + 1,
png_ptr->palette, png_ptr->trans_alpha, png_ptr->num_trans);
}
else
{
if (png_ptr->num_trans &&
(png_ptr->transformations & PNG_EXPAND_tRNS))
png_do_expand(row_info, png_ptr->row_buf + 1,
&(png_ptr->trans_color));
else
png_do_expand(row_info, png_ptr->row_buf + 1,
NULL);
}
}
#endif
#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
if ((png_ptr->transformations & PNG_STRIP_ALPHA) &&
!(png_ptr->transformations & PNG_COMPOSE) &&
(row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
png_do_strip_channel(row_info, png_ptr->row_buf + 1,
0 /* at_start == false, because SWAP_ALPHA happens later */);
#endif
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
if (png_ptr->transformations & PNG_RGB_TO_GRAY)
{
int rgb_error =
png_do_rgb_to_gray(png_ptr, row_info,
png_ptr->row_buf + 1);
if (rgb_error)
{
png_ptr->rgb_to_gray_status=1;
if ((png_ptr->transformations & PNG_RGB_TO_GRAY) ==
PNG_RGB_TO_GRAY_WARN)
png_warning(png_ptr, "png_do_rgb_to_gray found nongray pixel");
if ((png_ptr->transformations & PNG_RGB_TO_GRAY) ==
PNG_RGB_TO_GRAY_ERR)
png_error(png_ptr, "png_do_rgb_to_gray found nongray pixel");
}
}
#endif
/* From Andreas Dilger e-mail to png-implement, 26 March 1998:
*
* In most cases, the "simple transparency" should be done prior to doing
* gray-to-RGB, or you will have to test 3x as many bytes to check if a
* pixel is transparent. You would also need to make sure that the
* transparency information is upgraded to RGB.
*
* To summarize, the current flow is:
* - Gray + simple transparency -> compare 1 or 2 gray bytes and composite
* with background "in place" if transparent,
* convert to RGB if necessary
* - Gray + alpha -> composite with gray background and remove alpha bytes,
* convert to RGB if necessary
*
* To support RGB backgrounds for gray images we need:
* - Gray + simple transparency -> convert to RGB + simple transparency,
* compare 3 or 6 bytes and composite with
* background "in place" if transparent
* (3x compare/pixel compared to doing
* composite with gray bkgrnd)
* - Gray + alpha -> convert to RGB + alpha, composite with background and
* remove alpha bytes (3x float
* operations/pixel compared with composite
* on gray background)
*
* Greg's change will do this. The reason it wasn't done before is for
* performance, as this increases the per-pixel operations. If we would check
* in advance if the background was gray or RGB, and position the gray-to-RGB
* transform appropriately, then it would save a lot of work/time.
*/
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
/* If gray -> RGB, do so now only if background is non-gray; else do later
* for performance reasons
*/
if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
!(png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
png_do_gray_to_rgb(row_info, png_ptr->row_buf + 1);
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
defined(PNG_READ_ALPHA_MODE_SUPPORTED)
if (png_ptr->transformations & PNG_COMPOSE)
png_do_compose(row_info, png_ptr->row_buf + 1, png_ptr);
#endif
#ifdef PNG_READ_GAMMA_SUPPORTED
if ((png_ptr->transformations & PNG_GAMMA) &&
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
/* Because RGB_TO_GRAY does the gamma transform. */
!(png_ptr->transformations & PNG_RGB_TO_GRAY) &&
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
defined(PNG_READ_ALPHA_MODE_SUPPORTED)
/* Because PNG_COMPOSE does the gamma transform if there is something to
* do (if there is an alpha channel or transparency.)
*/
!((png_ptr->transformations & PNG_COMPOSE) &&
((png_ptr->num_trans != 0) ||
(png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) &&
#endif
/* Because png_init_read_transformations transforms the palette, unless
* RGB_TO_GRAY will do the transform.
*/
(png_ptr->color_type != PNG_COLOR_TYPE_PALETTE))
png_do_gamma(row_info, png_ptr->row_buf + 1, png_ptr);
#endif
#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
if ((png_ptr->transformations & PNG_STRIP_ALPHA) &&
(png_ptr->transformations & PNG_COMPOSE) &&
(row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
png_do_strip_channel(row_info, png_ptr->row_buf + 1,
0 /* at_start == false, because SWAP_ALPHA happens later */);
#endif
#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
if ((png_ptr->transformations & PNG_ENCODE_ALPHA) &&
(row_info->color_type & PNG_COLOR_MASK_ALPHA))
png_do_encode_alpha(row_info, png_ptr->row_buf + 1, png_ptr);
#endif
#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
if (png_ptr->transformations & PNG_SCALE_16_TO_8)
png_do_scale_16_to_8(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
/* There is no harm in doing both of these because only one has any effect,
* by putting the 'scale' option first if the app asks for scale (either by
* calling the API or in a TRANSFORM flag) this is what happens.
*/
if (png_ptr->transformations & PNG_16_TO_8)
png_do_chop(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_QUANTIZE_SUPPORTED
if (png_ptr->transformations & PNG_QUANTIZE)
{
png_do_quantize(row_info, png_ptr->row_buf + 1,
png_ptr->palette_lookup, png_ptr->quantize_index);
if (row_info->rowbytes == 0)
png_error(png_ptr, "png_do_quantize returned rowbytes=0");
}
#endif /* PNG_READ_QUANTIZE_SUPPORTED */
#ifdef PNG_READ_EXPAND_16_SUPPORTED
/* Do the expansion now, after all the arithmetic has been done. Notice
* that previous transformations can handle the PNG_EXPAND_16 flag if this
* is efficient (particularly true in the case of gamma correction, where
* better accuracy results faster!)
*/
if (png_ptr->transformations & PNG_EXPAND_16)
png_do_expand_16(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
/* NOTE: moved here in 1.5.4 (from much later in this list.) */
if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
(png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
png_do_gray_to_rgb(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_INVERT_SUPPORTED
if (png_ptr->transformations & PNG_INVERT_MONO)
png_do_invert(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_SHIFT_SUPPORTED
if (png_ptr->transformations & PNG_SHIFT)
png_do_unshift(row_info, png_ptr->row_buf + 1,
&(png_ptr->shift));
#endif
#ifdef PNG_READ_PACK_SUPPORTED
if (png_ptr->transformations & PNG_PACK)
png_do_unpack(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
/* Added at libpng-1.5.10 */
if (row_info->color_type == PNG_COLOR_TYPE_PALETTE &&
png_ptr->num_palette_max >= 0)
png_do_check_palette_indexes(png_ptr, row_info);
#endif
#ifdef PNG_READ_BGR_SUPPORTED
if (png_ptr->transformations & PNG_BGR)
png_do_bgr(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_PACKSWAP_SUPPORTED
if (png_ptr->transformations & PNG_PACKSWAP)
png_do_packswap(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_FILLER_SUPPORTED
if (png_ptr->transformations & PNG_FILLER)
png_do_read_filler(row_info, png_ptr->row_buf + 1,
(png_uint_32)png_ptr->filler, png_ptr->flags);
#endif
#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
if (png_ptr->transformations & PNG_INVERT_ALPHA)
png_do_read_invert_alpha(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
if (png_ptr->transformations & PNG_SWAP_ALPHA)
png_do_read_swap_alpha(row_info, png_ptr->row_buf + 1);
#endif
#ifdef PNG_READ_16BIT_SUPPORTED
#ifdef PNG_READ_SWAP_SUPPORTED
if (png_ptr->transformations & PNG_SWAP_BYTES)
png_do_swap(row_info, png_ptr->row_buf + 1);
#endif
#endif
#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
if (png_ptr->transformations & PNG_USER_TRANSFORM)
{
if (png_ptr->read_user_transform_fn != NULL)
(*(png_ptr->read_user_transform_fn)) /* User read transform function */
(png_ptr, /* png_ptr */
row_info, /* row_info: */
/* png_uint_32 width; width of row */
/* png_size_t rowbytes; number of bytes in row */
/* png_byte color_type; color type of pixels */
/* png_byte bit_depth; bit depth of samples */
/* png_byte channels; number of channels (1-4) */
/* png_byte pixel_depth; bits per pixel (depth*channels) */
png_ptr->row_buf + 1); /* start of pixel data for row */
#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
if (png_ptr->user_transform_depth)
row_info->bit_depth = png_ptr->user_transform_depth;
if (png_ptr->user_transform_channels)
row_info->channels = png_ptr->user_transform_channels;
#endif
row_info->pixel_depth = (png_byte)(row_info->bit_depth *
row_info->channels);
row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_info->width);
}
#endif
} | /* Transform the row. The order of transformations is significant,
* and is very touchy. If you add a transformation, take care to
* decide how it fits in with the other transformations here.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L2126-L2417 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_do_unpack | void /* PRIVATE */
png_do_unpack(png_row_infop row_info, png_bytep row)
{
png_debug(1, "in png_do_unpack");
if (row_info->bit_depth < 8)
{
png_uint_32 i;
png_uint_32 row_width=row_info->width;
switch (row_info->bit_depth)
{
case 1:
{
png_bytep sp = row + (png_size_t)((row_width - 1) >> 3);
png_bytep dp = row + (png_size_t)row_width - 1;
png_uint_32 shift = 7 - (int)((row_width + 7) & 0x07);
for (i = 0; i < row_width; i++)
{
*dp = (png_byte)((*sp >> shift) & 0x01);
if (shift == 7)
{
shift = 0;
sp--;
}
else
shift++;
dp--;
}
break;
}
case 2:
{
png_bytep sp = row + (png_size_t)((row_width - 1) >> 2);
png_bytep dp = row + (png_size_t)row_width - 1;
png_uint_32 shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
for (i = 0; i < row_width; i++)
{
*dp = (png_byte)((*sp >> shift) & 0x03);
if (shift == 6)
{
shift = 0;
sp--;
}
else
shift += 2;
dp--;
}
break;
}
case 4:
{
png_bytep sp = row + (png_size_t)((row_width - 1) >> 1);
png_bytep dp = row + (png_size_t)row_width - 1;
png_uint_32 shift = (int)((1 - ((row_width + 1) & 0x01)) << 2);
for (i = 0; i < row_width; i++)
{
*dp = (png_byte)((*sp >> shift) & 0x0f);
if (shift == 4)
{
shift = 0;
sp--;
}
else
shift = 4;
dp--;
}
break;
}
default:
break;
}
row_info->bit_depth = 8;
row_info->pixel_depth = (png_byte)(8 * row_info->channels);
row_info->rowbytes = row_width * row_info->channels;
}
} | /* Unpack pixels of 1, 2, or 4 bits per pixel into 1 byte per pixel,
* without changing the actual values. Thus, if you had a row with
* a bit depth of 1, you would end up with bytes that only contained
* the numbers 0 or 1. If you would rather they contain 0 and 255, use
* png_do_shift() after this.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L2426-L2515 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_do_unshift | void /* PRIVATE */
png_do_unshift(png_row_infop row_info, png_bytep row,
png_const_color_8p sig_bits)
{
int color_type;
png_debug(1, "in png_do_unshift");
/* The palette case has already been handled in the _init routine. */
color_type = row_info->color_type;
if (color_type != PNG_COLOR_TYPE_PALETTE)
{
int shift[4];
int channels = 0;
int bit_depth = row_info->bit_depth;
if (color_type & PNG_COLOR_MASK_COLOR)
{
shift[channels++] = bit_depth - sig_bits->red;
shift[channels++] = bit_depth - sig_bits->green;
shift[channels++] = bit_depth - sig_bits->blue;
}
else
{
shift[channels++] = bit_depth - sig_bits->gray;
}
if (color_type & PNG_COLOR_MASK_ALPHA)
{
shift[channels++] = bit_depth - sig_bits->alpha;
}
{
int c, have_shift;
for (c = have_shift = 0; c < channels; ++c)
{
/* A shift of more than the bit depth is an error condition but it
* gets ignored here.
*/
if (shift[c] <= 0 || shift[c] >= bit_depth)
shift[c] = 0;
else
have_shift = 1;
}
if (!have_shift)
return;
}
switch (bit_depth)
{
default:
/* Must be 1bpp gray: should not be here! */
/* NOTREACHED */
break;
case 2:
/* Must be 2bpp gray */
/* assert(channels == 1 && shift[0] == 1) */
{
png_bytep bp = row;
png_bytep bp_end = bp + row_info->rowbytes;
while (bp < bp_end)
{
int b = (*bp >> 1) & 0x55;
*bp++ = (png_byte)b;
}
break;
}
case 4:
/* Must be 4bpp gray */
/* assert(channels == 1) */
{
png_bytep bp = row;
png_bytep bp_end = bp + row_info->rowbytes;
int gray_shift = shift[0];
int mask = 0xf >> gray_shift;
mask |= mask << 4;
while (bp < bp_end)
{
int b = (*bp >> gray_shift) & mask;
*bp++ = (png_byte)b;
}
break;
}
case 8:
/* Single byte components, G, GA, RGB, RGBA */
{
png_bytep bp = row;
png_bytep bp_end = bp + row_info->rowbytes;
int channel = 0;
while (bp < bp_end)
{
int b = *bp >> shift[channel];
if (++channel >= channels)
channel = 0;
*bp++ = (png_byte)b;
}
break;
}
#ifdef PNG_READ_16BIT_SUPPORTED
case 16:
/* Double byte components, G, GA, RGB, RGBA */
{
png_bytep bp = row;
png_bytep bp_end = bp + row_info->rowbytes;
int channel = 0;
while (bp < bp_end)
{
int value = (bp[0] << 8) + bp[1];
value >>= shift[channel];
if (++channel >= channels)
channel = 0;
*bp++ = (png_byte)(value >> 8);
*bp++ = (png_byte)(value & 0xff);
}
break;
}
#endif
}
}
} | /* Reverse the effects of png_do_shift. This routine merely shifts the
* pixels back to their significant bits values. Thus, if you have
* a row of bit depth 8, but only 5 are significant, this will shift
* the values back to 0 through 31.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L2524-L2658 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_do_scale_16_to_8 | void /* PRIVATE */
png_do_scale_16_to_8(png_row_infop row_info, png_bytep row)
{
png_debug(1, "in png_do_scale_16_to_8");
if (row_info->bit_depth == 16)
{
png_bytep sp = row; /* source */
png_bytep dp = row; /* destination */
png_bytep ep = sp + row_info->rowbytes; /* end+1 */
while (sp < ep)
{
/* The input is an array of 16 bit components, these must be scaled to
* 8 bits each. For a 16 bit value V the required value (from the PNG
* specification) is:
*
* (V * 255) / 65535
*
* This reduces to round(V / 257), or floor((V + 128.5)/257)
*
* Represent V as the two byte value vhi.vlo. Make a guess that the
* result is the top byte of V, vhi, then the correction to this value
* is:
*
* error = floor(((V-vhi.vhi) + 128.5) / 257)
* = floor(((vlo-vhi) + 128.5) / 257)
*
* This can be approximated using integer arithmetic (and a signed
* shift):
*
* error = (vlo-vhi+128) >> 8;
*
* The approximate differs from the exact answer only when (vlo-vhi) is
* 128; it then gives a correction of +1 when the exact correction is
* 0. This gives 128 errors. The exact answer (correct for all 16 bit
* input values) is:
*
* error = (vlo-vhi+128)*65535 >> 24;
*
* An alternative arithmetic calculation which also gives no errors is:
*
* (V * 255 + 32895) >> 16
*/
png_int_32 tmp = *sp++; /* must be signed! */
tmp += (((int)*sp++ - tmp + 128) * 65535) >> 24;
*dp++ = (png_byte)tmp;
}
row_info->bit_depth = 8;
row_info->pixel_depth = (png_byte)(8 * row_info->channels);
row_info->rowbytes = row_info->width * row_info->channels;
}
} | /* Scale rows of bit depth 16 down to 8 accurately */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L2663-L2717 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_do_read_filler | void /* PRIVATE */
png_do_read_filler(png_row_infop row_info, png_bytep row,
png_uint_32 filler, png_uint_32 flags)
{
png_uint_32 i;
png_uint_32 row_width = row_info->width;
#ifdef PNG_READ_16BIT_SUPPORTED
png_byte hi_filler = (png_byte)((filler>>8) & 0xff);
#endif
png_byte lo_filler = (png_byte)(filler & 0xff);
png_debug(1, "in png_do_read_filler");
if (
row_info->color_type == PNG_COLOR_TYPE_GRAY)
{
if (row_info->bit_depth == 8)
{
if (flags & PNG_FLAG_FILLER_AFTER)
{
/* This changes the data from G to GX */
png_bytep sp = row + (png_size_t)row_width;
png_bytep dp = sp + (png_size_t)row_width;
for (i = 1; i < row_width; i++)
{
*(--dp) = lo_filler;
*(--dp) = *(--sp);
}
*(--dp) = lo_filler;
row_info->channels = 2;
row_info->pixel_depth = 16;
row_info->rowbytes = row_width * 2;
}
else
{
/* This changes the data from G to XG */
png_bytep sp = row + (png_size_t)row_width;
png_bytep dp = sp + (png_size_t)row_width;
for (i = 0; i < row_width; i++)
{
*(--dp) = *(--sp);
*(--dp) = lo_filler;
}
row_info->channels = 2;
row_info->pixel_depth = 16;
row_info->rowbytes = row_width * 2;
}
}
#ifdef PNG_READ_16BIT_SUPPORTED
else if (row_info->bit_depth == 16)
{
if (flags & PNG_FLAG_FILLER_AFTER)
{
/* This changes the data from GG to GGXX */
png_bytep sp = row + (png_size_t)row_width * 2;
png_bytep dp = sp + (png_size_t)row_width * 2;
for (i = 1; i < row_width; i++)
{
*(--dp) = hi_filler;
*(--dp) = lo_filler;
*(--dp) = *(--sp);
*(--dp) = *(--sp);
}
*(--dp) = hi_filler;
*(--dp) = lo_filler;
row_info->channels = 2;
row_info->pixel_depth = 32;
row_info->rowbytes = row_width * 4;
}
else
{
/* This changes the data from GG to XXGG */
png_bytep sp = row + (png_size_t)row_width * 2;
png_bytep dp = sp + (png_size_t)row_width * 2;
for (i = 0; i < row_width; i++)
{
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = hi_filler;
*(--dp) = lo_filler;
}
row_info->channels = 2;
row_info->pixel_depth = 32;
row_info->rowbytes = row_width * 4;
}
}
#endif
} /* COLOR_TYPE == GRAY */
else if (row_info->color_type == PNG_COLOR_TYPE_RGB)
{
if (row_info->bit_depth == 8)
{
if (flags & PNG_FLAG_FILLER_AFTER)
{
/* This changes the data from RGB to RGBX */
png_bytep sp = row + (png_size_t)row_width * 3;
png_bytep dp = sp + (png_size_t)row_width;
for (i = 1; i < row_width; i++)
{
*(--dp) = lo_filler;
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
}
*(--dp) = lo_filler;
row_info->channels = 4;
row_info->pixel_depth = 32;
row_info->rowbytes = row_width * 4;
}
else
{
/* This changes the data from RGB to XRGB */
png_bytep sp = row + (png_size_t)row_width * 3;
png_bytep dp = sp + (png_size_t)row_width;
for (i = 0; i < row_width; i++)
{
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = lo_filler;
}
row_info->channels = 4;
row_info->pixel_depth = 32;
row_info->rowbytes = row_width * 4;
}
}
#ifdef PNG_READ_16BIT_SUPPORTED
else if (row_info->bit_depth == 16)
{
if (flags & PNG_FLAG_FILLER_AFTER)
{
/* This changes the data from RRGGBB to RRGGBBXX */
png_bytep sp = row + (png_size_t)row_width * 6;
png_bytep dp = sp + (png_size_t)row_width * 2;
for (i = 1; i < row_width; i++)
{
*(--dp) = hi_filler;
*(--dp) = lo_filler;
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
}
*(--dp) = hi_filler;
*(--dp) = lo_filler;
row_info->channels = 4;
row_info->pixel_depth = 64;
row_info->rowbytes = row_width * 8;
}
else
{
/* This changes the data from RRGGBB to XXRRGGBB */
png_bytep sp = row + (png_size_t)row_width * 6;
png_bytep dp = sp + (png_size_t)row_width * 2;
for (i = 0; i < row_width; i++)
{
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = hi_filler;
*(--dp) = lo_filler;
}
row_info->channels = 4;
row_info->pixel_depth = 64;
row_info->rowbytes = row_width * 8;
}
}
#endif
} /* COLOR_TYPE == RGB */
} | /* Add filler channel if we have RGB color */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L2948-L3130 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_do_gray_to_rgb | void /* PRIVATE */
png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
{
png_uint_32 i;
png_uint_32 row_width = row_info->width;
png_debug(1, "in png_do_gray_to_rgb");
if (row_info->bit_depth >= 8 &&
!(row_info->color_type & PNG_COLOR_MASK_COLOR))
{
if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
{
if (row_info->bit_depth == 8)
{
/* This changes G to RGB */
png_bytep sp = row + (png_size_t)row_width - 1;
png_bytep dp = sp + (png_size_t)row_width * 2;
for (i = 0; i < row_width; i++)
{
*(dp--) = *sp;
*(dp--) = *sp;
*(dp--) = *(sp--);
}
}
else
{
/* This changes GG to RRGGBB */
png_bytep sp = row + (png_size_t)row_width * 2 - 1;
png_bytep dp = sp + (png_size_t)row_width * 4;
for (i = 0; i < row_width; i++)
{
*(dp--) = *sp;
*(dp--) = *(sp - 1);
*(dp--) = *sp;
*(dp--) = *(sp - 1);
*(dp--) = *(sp--);
*(dp--) = *(sp--);
}
}
}
else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
{
if (row_info->bit_depth == 8)
{
/* This changes GA to RGBA */
png_bytep sp = row + (png_size_t)row_width * 2 - 1;
png_bytep dp = sp + (png_size_t)row_width * 2;
for (i = 0; i < row_width; i++)
{
*(dp--) = *(sp--);
*(dp--) = *sp;
*(dp--) = *sp;
*(dp--) = *(sp--);
}
}
else
{
/* This changes GGAA to RRGGBBAA */
png_bytep sp = row + (png_size_t)row_width * 4 - 1;
png_bytep dp = sp + (png_size_t)row_width * 4;
for (i = 0; i < row_width; i++)
{
*(dp--) = *(sp--);
*(dp--) = *(sp--);
*(dp--) = *sp;
*(dp--) = *(sp - 1);
*(dp--) = *sp;
*(dp--) = *(sp - 1);
*(dp--) = *(sp--);
*(dp--) = *(sp--);
}
}
}
row_info->channels = (png_byte)(row_info->channels + 2);
row_info->color_type |= PNG_COLOR_MASK_COLOR;
row_info->pixel_depth = (png_byte)(row_info->channels *
row_info->bit_depth);
row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
}
} | /* Expand grayscale files to RGB, with or without alpha */ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L3135-L3218 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_do_rgb_to_gray | int /* PRIVATE */
png_do_rgb_to_gray(png_structrp png_ptr, png_row_infop row_info, png_bytep row)
{
int rgb_error = 0;
png_debug(1, "in png_do_rgb_to_gray");
if (!(row_info->color_type & PNG_COLOR_MASK_PALETTE) &&
(row_info->color_type & PNG_COLOR_MASK_COLOR))
{
PNG_CONST png_uint_32 rc = png_ptr->rgb_to_gray_red_coeff;
PNG_CONST png_uint_32 gc = png_ptr->rgb_to_gray_green_coeff;
PNG_CONST png_uint_32 bc = 32768 - rc - gc;
PNG_CONST png_uint_32 row_width = row_info->width;
PNG_CONST int have_alpha =
(row_info->color_type & PNG_COLOR_MASK_ALPHA) != 0;
if (row_info->bit_depth == 8)
{
#ifdef PNG_READ_GAMMA_SUPPORTED
/* Notice that gamma to/from 1 are not necessarily inverses (if
* there is an overall gamma correction). Prior to 1.5.5 this code
* checked the linearized values for equality; this doesn't match
* the documentation, the original values must be checked.
*/
if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL)
{
png_bytep sp = row;
png_bytep dp = row;
png_uint_32 i;
for (i = 0; i < row_width; i++)
{
png_byte red = *(sp++);
png_byte green = *(sp++);
png_byte blue = *(sp++);
if (red != green || red != blue)
{
red = png_ptr->gamma_to_1[red];
green = png_ptr->gamma_to_1[green];
blue = png_ptr->gamma_to_1[blue];
rgb_error |= 1;
*(dp++) = png_ptr->gamma_from_1[
(rc*red + gc*green + bc*blue + 16384)>>15];
}
else
{
/* If there is no overall correction the table will not be
* set.
*/
if (png_ptr->gamma_table != NULL)
red = png_ptr->gamma_table[red];
*(dp++) = red;
}
if (have_alpha)
*(dp++) = *(sp++);
}
}
else
#endif
{
png_bytep sp = row;
png_bytep dp = row;
png_uint_32 i;
for (i = 0; i < row_width; i++)
{
png_byte red = *(sp++);
png_byte green = *(sp++);
png_byte blue = *(sp++);
if (red != green || red != blue)
{
rgb_error |= 1;
/* NOTE: this is the historical approach which simply
* truncates the results.
*/
*(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15);
}
else
*(dp++) = red;
if (have_alpha)
*(dp++) = *(sp++);
}
}
}
else /* RGB bit_depth == 16 */
{
#ifdef PNG_READ_GAMMA_SUPPORTED
if (png_ptr->gamma_16_to_1 != NULL && png_ptr->gamma_16_from_1 != NULL)
{
png_bytep sp = row;
png_bytep dp = row;
png_uint_32 i;
for (i = 0; i < row_width; i++)
{
png_uint_16 red, green, blue, w;
red = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
green = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
blue = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
if (red == green && red == blue)
{
if (png_ptr->gamma_16_table != NULL)
w = png_ptr->gamma_16_table[(red&0xff)
>> png_ptr->gamma_shift][red>>8];
else
w = red;
}
else
{
png_uint_16 red_1 = png_ptr->gamma_16_to_1[(red&0xff)
>> png_ptr->gamma_shift][red>>8];
png_uint_16 green_1 =
png_ptr->gamma_16_to_1[(green&0xff) >>
png_ptr->gamma_shift][green>>8];
png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff)
>> png_ptr->gamma_shift][blue>>8];
png_uint_16 gray16 = (png_uint_16)((rc*red_1 + gc*green_1
+ bc*blue_1 + 16384)>>15);
w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
png_ptr->gamma_shift][gray16 >> 8];
rgb_error |= 1;
}
*(dp++) = (png_byte)((w>>8) & 0xff);
*(dp++) = (png_byte)(w & 0xff);
if (have_alpha)
{
*(dp++) = *(sp++);
*(dp++) = *(sp++);
}
}
}
else
#endif
{
png_bytep sp = row;
png_bytep dp = row;
png_uint_32 i;
for (i = 0; i < row_width; i++)
{
png_uint_16 red, green, blue, gray16;
red = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
green = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
blue = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
if (red != green || red != blue)
rgb_error |= 1;
/* From 1.5.5 in the 16 bit case do the accurate conversion even
* in the 'fast' case - this is because this is where the code
* ends up when handling linear 16 bit data.
*/
gray16 = (png_uint_16)((rc*red + gc*green + bc*blue + 16384) >>
15);
*(dp++) = (png_byte)((gray16>>8) & 0xff);
*(dp++) = (png_byte)(gray16 & 0xff);
if (have_alpha)
{
*(dp++) = *(sp++);
*(dp++) = *(sp++);
}
}
}
}
row_info->channels = (png_byte)(row_info->channels - 2);
row_info->color_type = (png_byte)(row_info->color_type &
~PNG_COLOR_MASK_COLOR);
row_info->pixel_depth = (png_byte)(row_info->channels *
row_info->bit_depth);
row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
}
return rgb_error;
} | /* Reduce RGB files to grayscale, with or without alpha
* using the equation given in Poynton's ColorFAQ of 1998-01-04 at
* <http://www.inforamp.net/~poynton/> (THIS LINK IS DEAD June 2008 but
* versions dated 1998 through November 2002 have been archived at
* http://web.archive.org/web/20000816232553/http://www.inforamp.net/
* ~poynton/notes/colour_and_gamma/ColorFAQ.txt )
* Charles Poynton poynton at poynton.com
*
* Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
*
* which can be expressed with integers as
*
* Y = (6969 * R + 23434 * G + 2365 * B)/32768
*
* Poynton's current link (as of January 2003 through July 2011):
* <http://www.poynton.com/notes/colour_and_gamma/>
* has changed the numbers slightly:
*
* Y = 0.2126*R + 0.7152*G + 0.0722*B
*
* which can be expressed with integers as
*
* Y = (6966 * R + 23436 * G + 2366 * B)/32768
*
* Historically, however, libpng uses numbers derived from the ITU-R Rec 709
* end point chromaticities and the D65 white point. Depending on the
* precision used for the D65 white point this produces a variety of different
* numbers, however if the four decimal place value used in ITU-R Rec 709 is
* used (0.3127,0.3290) the Y calculation would be:
*
* Y = (6968 * R + 23435 * G + 2366 * B)/32768
*
* While this is correct the rounding results in an overflow for white, because
* the sum of the rounded coefficients is 32769, not 32768. Consequently
* libpng uses, instead, the closest non-overflowing approximation:
*
* Y = (6968 * R + 23434 * G + 2366 * B)/32768
*
* Starting with libpng-1.5.5, if the image being converted has a cHRM chunk
* (including an sRGB chunk) then the chromaticities are used to calculate the
* coefficients. See the chunk handling in pngrutil.c for more information.
*
* In all cases the calculation is to be done in a linear colorspace. If no
* gamma information is available to correct the encoding of the original RGB
* values this results in an implicit assumption that the original PNG RGB
* values were linear.
*
* Other integer coefficents can be used via png_set_rgb_to_gray(). Because
* the API takes just red and green coefficients the blue coefficient is
* calculated to make the sum 32768. This will result in different rounding
* to that used above.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L3274-L3466 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
BigWorld-Engine-14.4.1 | github_2023 | v2v3v4 | c | png_build_grayscale_palette | void PNGAPI
png_build_grayscale_palette(int bit_depth, png_colorp palette)
{
int num_palette;
int color_inc;
int i;
int v;
png_debug(1, "in png_do_build_grayscale_palette");
if (palette == NULL)
return;
switch (bit_depth)
{
case 1:
num_palette = 2;
color_inc = 0xff;
break;
case 2:
num_palette = 4;
color_inc = 0x55;
break;
case 4:
num_palette = 16;
color_inc = 0x11;
break;
case 8:
num_palette = 256;
color_inc = 1;
break;
default:
num_palette = 0;
color_inc = 0;
break;
}
for (i = 0, v = 0; i < num_palette; i++, v += color_inc)
{
palette[i].red = (png_byte)v;
palette[i].green = (png_byte)v;
palette[i].blue = (png_byte)v;
}
} | /* Build a grayscale palette. Palette is assumed to be 1 << bit_depth
* large of png_color. This lets grayscale images be treated as
* paletted. Most useful for gamma correction and simplification
* of code. This API is not used internally.
*/ | https://github.com/v2v3v4/BigWorld-Engine-14.4.1/blob/4389085c8ce35cff887a4cc18fc47d1133d89ffb/programming/bigworld/third_party/png/pngrtran.c#L3476-L3523 | 4389085c8ce35cff887a4cc18fc47d1133d89ffb |
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