Spaces:
Running on Zero
Running on Zero
File size: 3,090 Bytes
db89723 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 |
from pathlib import Path
from PIL import Image
DEFAULT_TILE_SIZE = 128
DEFAULT_OVERLAP = 32
def calculate_positions(length, tile_size, overlap):
"""
Calculate tile starting positions along one dimension.
The final tile always reaches the image boundary.
"""
if tile_size <= 0:
raise ValueError("tile_size must be positive.")
if overlap < 0 or overlap >= tile_size:
raise ValueError(
"overlap must satisfy 0 <= overlap < tile_size."
)
stride = tile_size - overlap
if length <= tile_size:
return [0]
positions = list(range(0, length - tile_size + 1, stride))
# Ensure the final region is covered.
last_position = length - tile_size
if positions[-1] != last_position:
positions.append(last_position)
return positions
def create_tiles(
image,
tile_size=DEFAULT_TILE_SIZE,
overlap=DEFAULT_OVERLAP
):
"""
Split a PIL image into overlapping tiles.
Returns:
list of dictionaries containing:
image
x
y
width
height
index
"""
if not isinstance(image, Image.Image):
raise TypeError(
"image must be a PIL.Image.Image"
)
image = image.convert("RGB")
width, height = image.size
x_positions = calculate_positions(
width,
tile_size,
overlap
)
y_positions = calculate_positions(
height,
tile_size,
overlap
)
tiles = []
index = 0
for y in y_positions:
for x in x_positions:
right = min(
x + tile_size,
width
)
bottom = min(
y + tile_size,
height
)
tile = image.crop(
(x, y, right, bottom)
)
tiles.append(
{
"image": tile,
"x": x,
"y": y,
"width": right - x,
"height": bottom - y,
"index": index
}
)
index += 1
return tiles
def save_tiles(
tiles,
output_dir,
prefix="tile"
):
"""
Save generated tiles to disk.
"""
output_dir = Path(output_dir)
output_dir.mkdir(
parents=True,
exist_ok=True
)
metadata = []
for tile_info in tiles:
image = tile_info["image"]
filename = (
f"{prefix}_"
f"{tile_info['index']:03d}_"
f"x{tile_info['x']}_"
f"y{tile_info['y']}.png"
)
path = output_dir / filename
image.save(path)
metadata.append(
{
"index": tile_info["index"],
"x": tile_info["x"],
"y": tile_info["y"],
"width": tile_info["width"],
"height": tile_info["height"],
"filename": filename
}
)
return metadata
|