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		<link rel="modulepreload" href="/docs/diffusers/main/en/_app/immutable/chunks/HfOption.fad27e59.js"><!-- HEAD_svelte-u9bgzb_START --><meta name="hf:doc:metadata" content="{&quot;title&quot;:&quot;SequentialPipelineBlocks&quot;,&quot;local&quot;:&quot;sequentialpipelineblocks&quot;,&quot;sections&quot;:[],&quot;depth&quot;:1}"><!-- HEAD_svelte-u9bgzb_END -->      <p></p>   <div class="items-center shrink-0 min-w-[100px] max-sm:min-w-[50px] justify-end ml-auto flex" style="float: right; margin-left: 10px; display: inline-flex; position: relative; z-index: 10;"><div class="inline-flex rounded-md max-sm:rounded-sm"><button class="inline-flex items-center gap-1 h-7 max-sm:h-7 px-2 max-sm:px-1.5 text-sm font-medium text-gray-800 border border-r-0 rounded-l-md max-sm:rounded-l-sm border-gray-200 bg-white hover:shadow-inner dark:border-gray-850 dark:bg-gray-950 dark:text-gray-200 dark:hover:bg-gray-800" aria-live="polite"><span class="inline-flex items-center justify-center rounded-md p-0.5 max-sm:p-0 hover:text-gray-800 dark:hover:text-gray-200"><svg class="sm:size-3.5 size-3" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg></span> <span>Copy page</span></button> <button class="inline-flex items-center justify-center w-6 max-sm:w-5 h-7 max-sm:h-7 disabled:pointer-events-none text-sm text-gray-500 hover:text-gray-700 dark:hover:text-white rounded-r-md max-sm:rounded-r-sm border border-l transition border-gray-200 bg-white hover:shadow-inner dark:border-gray-850 dark:bg-gray-950 dark:text-gray-200 dark:hover:bg-gray-800" aria-haspopup="menu" aria-expanded="false" aria-label="Open copy menu"><svg class="transition-transform text-gray-400 overflow-visible sm:size-3.5 size-3 rotate-0" width="1em" height="1em" viewBox="0 0 12 7" fill="none" xmlns="http://www.w3.org/2000/svg"><path d="M1 1L6 6L11 1" stroke="currentColor"></path></svg></button></div> </div>  <h1 class="relative group"><a id="sequentialpipelineblocks" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#sequentialpipelineblocks"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>SequentialPipelineBlocks</span></h1> <p data-svelte-h="svelte-p6vcuq"><a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_blocks#diffusers.SequentialPipelineBlocks">SequentialPipelineBlocks</a> are a multi-block type that composes other <a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_blocks#diffusers.ModularPipelineBlocks">ModularPipelineBlocks</a> together in a sequence. Data flows linearly from one block to the next using <code>inputs</code> and <code>intermediate_outputs</code>. Each block in <a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_blocks#diffusers.SequentialPipelineBlocks">SequentialPipelineBlocks</a> usually represents a step in the pipeline, and by combining them, you gradually build a pipeline.</p> <p data-svelte-h="svelte-gi2z0i">This guide shows you how to connect two blocks into a <a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_blocks#diffusers.SequentialPipelineBlocks">SequentialPipelineBlocks</a>.</p> <p data-svelte-h="svelte-10eyw45">Create two <a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_blocks#diffusers.ModularPipelineBlocks">ModularPipelineBlocks</a>. The first block, <code>InputBlock</code>, outputs a <code>batch_size</code> value and the second block, <code>ImageEncoderBlock</code> uses <code>batch_size</code> as <code>inputs</code>.</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white">InputBlock </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm">ImageEncoderBlock </div></div> <div class="language-select"><div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5   text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> diffusers.modular_pipelines <span class="hljs-keyword">import</span> ModularPipelineBlocks, InputParam, OutputParam

<span class="hljs-keyword">class</span> <span class="hljs-title class_">InputBlock</span>(<span class="hljs-title class_ inherited__">ModularPipelineBlocks</span>):

<span class="hljs-meta">    @property</span>
    <span class="hljs-keyword">def</span> <span class="hljs-title function_">inputs</span>(<span class="hljs-params">self</span>):
        <span class="hljs-keyword">return</span> [
            InputParam(name=<span class="hljs-string">&quot;prompt&quot;</span>, type_hint=<span class="hljs-built_in">list</span>, description=<span class="hljs-string">&quot;list of text prompts&quot;</span>),
            InputParam(name=<span class="hljs-string">&quot;num_images_per_prompt&quot;</span>, type_hint=<span class="hljs-built_in">int</span>, description=<span class="hljs-string">&quot;number of images per prompt&quot;</span>),
        ]

<span class="hljs-meta">    @property</span>
    <span class="hljs-keyword">def</span> <span class="hljs-title function_">intermediate_outputs</span>(<span class="hljs-params">self</span>):
        <span class="hljs-keyword">return</span> [
            OutputParam(name=<span class="hljs-string">&quot;batch_size&quot;</span>, description=<span class="hljs-string">&quot;calculated batch size&quot;</span>),
        ]

<span class="hljs-meta">    @property</span>
    <span class="hljs-keyword">def</span> <span class="hljs-title function_">description</span>(<span class="hljs-params">self</span>):
        <span class="hljs-keyword">return</span> <span class="hljs-string">&quot;A block that determines batch_size based on the number of prompts and num_images_per_prompt argument.&quot;</span>

    <span class="hljs-keyword">def</span> <span class="hljs-title function_">__call__</span>(<span class="hljs-params">self, components, state</span>):
        block_state = self.get_block_state(state)
        batch_size = <span class="hljs-built_in">len</span>(block_state.prompt)
        block_state.batch_size = batch_size * block_state.num_images_per_prompt
        self.set_block_state(state, block_state)
        <span class="hljs-keyword">return</span> components, state<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-6vyu6n">Connect the two blocks by defining a <a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_blocks#diffusers.SequentialPipelineBlocks">SequentialPipelineBlocks</a>. List the block instances in <code>block_classes</code> and their corresponding names in <code>block_names</code>. The blocks are executed in the order they appear in <code>block_classes</code>, and data flows from one block to the next through <a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_states#diffusers.modular_pipelines.PipelineState">PipelineState</a>.</p> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5   text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">class</span> <span class="hljs-title class_">ImageProcessingStep</span>(<span class="hljs-title class_ inherited__">SequentialPipelineBlocks</span>):
    <span class="hljs-string">&quot;&quot;&quot;
    # auto_docstring
    &quot;&quot;&quot;</span>
    model_name = <span class="hljs-string">&quot;my_model&quot;</span>
    block_classes = [InputBlock(), ImageEncoderBlock()]
    block_names = [<span class="hljs-string">&quot;input&quot;</span>, <span class="hljs-string">&quot;image_encoder&quot;</span>]

<span class="hljs-meta">    @property</span>
    <span class="hljs-keyword">def</span> <span class="hljs-title function_">description</span>(<span class="hljs-params">self</span>):
        <span class="hljs-keyword">return</span> (
            <span class="hljs-string">&quot;Process text prompts and images for the pipeline. It:\n&quot;</span>
            <span class="hljs-string">&quot; - Determines the batch size from the prompts.\n&quot;</span>
            <span class="hljs-string">&quot; - Encodes the image into latent space.&quot;</span>
        )<!-- HTML_TAG_END --></pre></div> <p data-svelte-h="svelte-1ovhm7s">When you create a <a href="/docs/diffusers/main/en/api/modular_diffusers/pipeline_blocks#diffusers.SequentialPipelineBlocks">SequentialPipelineBlocks</a>, properties like <code>inputs</code>, <code>intermediate_outputs</code>, and <code>expected_components</code> are automatically aggregated from the sub-blocks, so there is no need to define them again.</p> <p data-svelte-h="svelte-1jm02rm">There are a few properties you should set:</p> <ul data-svelte-h="svelte-4pf42"><li><code>description</code>: We recommend adding a description for the assembled block to explain what the combined step does.</li> <li><code>model_name</code>: This is automatically derived from the sub-blocks but isn’t always correct, so you may need to override it.</li> <li><code>outputs</code>: By default this is the same as <code>intermediate_outputs</code>, but you can manually set it to control which values appear in the doc. This is useful for showing only the final outputs instead of all intermediate values.</li></ul> <p data-svelte-h="svelte-g4j0d1">These properties, together with the aggregated <code>inputs</code>, <code>intermediate_outputs</code>, and <code>expected_components</code>, are used to automatically generate the <code>doc</code> property.</p> <p data-svelte-h="svelte-u486z9">Print the <code>ImageProcessingStep</code> block to inspect its sub-blocks, and use <code>doc</code> for a full summary of the block’s inputs, outputs, and components.</p> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5   text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->blocks = ImageProcessingStep()
<span class="hljs-built_in">print</span>(blocks)
<span class="hljs-built_in">print</span>(blocks.doc)<!-- HTML_TAG_END --></pre></div> <a class="!text-gray-400 !no-underline text-sm flex items-center not-prose mt-4" href="https://github.com/huggingface/diffusers/blob/main/docs/source/en/modular_diffusers/sequential_pipeline_blocks.md" target="_blank"><svg class="mr-1" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M31,16l-7,7l-1.41-1.41L28.17,16l-5.58-5.59L24,9l7,7z"></path><path d="M1,16l7-7l1.41,1.41L3.83,16l5.58,5.59L8,23l-7-7z"></path><path d="M12.419,25.484L17.639,6.552l1.932,0.518L14.351,26.002z"></path></svg> <span data-svelte-h="svelte-zjs2n5"><span class="underline">Update</span> on GitHub</span></a>  <p></p> 
			
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