---
title: request_adapter
---

<div class="python-reference">
<a id="fastvideo.entrypoints.openai.request_adapter-classes"></a>
<a id="fastvideo.entrypoints.openai.request_adapter-functions"></a>
<a id="fastvideo.entrypoints.openai.request_adapter"></a>
<p>Translate OpenAI/vLLM-Omni requests into FastVideo's typed request API.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.MediaPolicy"><code>fastvideo.entrypoints.openai.request_adapter.MediaPolicy</code></h2>
<pre class="doc-signature"><code>MediaPolicy(roots: tuple&#91;str, ...&#93; = (), allow_private_urls: bool = False)</code></pre>


<h2 id="fastvideo.entrypoints.openai.request_adapter.MediaPolicyError"><code>fastvideo.entrypoints.openai.request_adapter.MediaPolicyError</code></h2>
<pre class="doc-signature"><code>MediaPolicyError()</code></pre>
<p>A media reference is not allowed by the server's media policy.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.discard"><code>fastvideo.entrypoints.openai.request_adapter.discard</code></h2>
<pre class="doc-signature"><code>discard(path: str) -&gt; None</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.fetch_media"><code>fastvideo.entrypoints.openai.request_adapter.fetch_media</code></h2>
<pre class="doc-signature"><code>fetch_media(url: str, target: str, *, max_bytes: int, policy: MediaPolicy, transport: httpx.AsyncBaseTransport | None = None) -&gt; httpx.Headers</code></pre>
<p>Download <code>url</code> to <code>target</code> under <code>policy</code>; returns the final response headers.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.resolve_local_media"><code>fastvideo.entrypoints.openai.request_adapter.resolve_local_media</code></h2>
<pre class="doc-signature"><code>resolve_local_media(source: str, policy: MediaPolicy) -&gt; str</code></pre>
<p>Return the real path of a caller-supplied local file inside a configured root.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.get_media_policy"><code>fastvideo.entrypoints.openai.request_adapter.get_media_policy</code></h2>
<pre class="doc-signature"><code>get_media_policy() -&gt; MediaPolicy</code></pre>
<p>Return the local-root and private-address rules for caller media references.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.get_media_reference_max_bytes"><code>fastvideo.entrypoints.openai.request_adapter.get_media_reference_max_bytes</code></h2>
<pre class="doc-signature"><code>get_media_reference_max_bytes() -&gt; int</code></pre>
<p>Return the server's URL media-reference byte cap.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.explicit_request_updates"><code>fastvideo.entrypoints.openai.request_adapter.explicit_request_updates</code></h2>
<pre class="doc-signature"><code>explicit_request_updates(request: GenerationRequest) -&gt; dict&#91;str, Any&#93;</code></pre>
<p>Project a <code>GenerationRequest</code> down to <em>explicitly set</em> fields only.</p>
<p>Returns a flat kwargs dict suitable for merging into a generator call.
The projection uses <code>_fastvideo_explicit_paths</code> (populated during
<code>parse_config</code> / raw binding) so schema defaults on the dataclass
are <strong>not</strong> emitted — only paths the caller/operator actually wrote.</p>
<p>This is what makes <code>ServeConfig.default_request</code> work as an
operator-pinned baseline rather than a full override: a YAML with just
<code>sampling.seed: 42</code> yields <code>&#123;"seed": 42&#125;</code>, not the full sampling
config with its 15 schema defaults.</p>
<p>Precondition: the request must carry <code>_fastvideo_explicit_paths</code> —
populated by :func:<code>fastvideo.api.parser.parse_config</code> or
:func:<code>fastvideo.api.compat.normalize_generation_request</code>. Calling on
a raw <code>GenerationRequest()</code> asserts.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.legacy_generate_call_to_request"><code>fastvideo.entrypoints.openai.request_adapter.legacy_generate_call_to_request</code></h2>
<pre class="doc-signature"><code>legacy_generate_call_to_request(prompt: str | None, sampling_param: SamplingParam | None, *, mouse_cond: Any | None = None, keyboard_cond: Any | None = None, grid_sizes: Any | None = None, legacy_kwargs: Mapping&#91;str, Any&#93; | None = None) -&gt; GenerationRequest</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.request_to_sampling_param"><code>fastvideo.entrypoints.openai.request_adapter.request_to_sampling_param</code></h2>
<pre class="doc-signature"><code>request_to_sampling_param(request: GenerationRequest, *, model_path: str) -&gt; SamplingParam</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.GenerationRequest"><code>fastvideo.entrypoints.openai.request_adapter.GenerationRequest</code></h2>
<pre class="doc-signature"><code>GenerationRequest(prompt: str | list&#91;str&#93; | None = None, negative_prompt: str | None = None, inputs: InputConfig = InputConfig(), sampling: SamplingConfig = SamplingConfig(), runtime: RequestRuntimeConfig = RequestRuntimeConfig(), output: OutputConfig = OutputConfig(), stage_overrides: dict&#91;str, Any&#93; = dict(), state: ContinuationState | None = None, plan: GenerationPlan | None = None, extensions: dict&#91;str, Any&#93; = dict())</code></pre>


<h2 id="fastvideo.entrypoints.openai.request_adapter.FileImageReference"><code>fastvideo.entrypoints.openai.request_adapter.FileImageReference</code></h2>
<pre class="doc-signature"><code>FileImageReference()</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.FileVideoReference"><code>fastvideo.entrypoints.openai.request_adapter.FileVideoReference</code></h2>
<pre class="doc-signature"><code>FileVideoReference()</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.UrlImageReference"><code>fastvideo.entrypoints.openai.request_adapter.UrlImageReference</code></h2>
<pre class="doc-signature"><code>UrlImageReference()</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.UrlVideoReference"><code>fastvideo.entrypoints.openai.request_adapter.UrlVideoReference</code></h2>
<pre class="doc-signature"><code>UrlVideoReference()</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.VideoGenerationRequest"><code>fastvideo.entrypoints.openai.request_adapter.VideoGenerationRequest</code></h2>
<pre class="doc-signature"><code>VideoGenerationRequest()</code></pre>
<p>OpenAI/vLLM-Omni-compatible video generation request.</p>
<p>Model-specific parameters belong in <code>extra_params</code>. FastVideo keeps the
legacy <code>input_reference</code> and <code>reference_url</code> fields for clients that
predate vLLM-Omni's typed reference objects.</p>
<h3 id="fastvideo.entrypoints.openai.request_adapter.VideoGenerationRequest.validate_prompt"><code>fastvideo.entrypoints.openai.request_adapter.VideoGenerationRequest.validate_prompt</code></h3>
<pre class="doc-signature"><code>validate_prompt(value: str) -&gt; str</code></pre>

<h3 id="fastvideo.entrypoints.openai.request_adapter.VideoGenerationRequest.resolve_video_params"><code>fastvideo.entrypoints.openai.request_adapter.VideoGenerationRequest.resolve_video_params</code></h3>
<pre class="doc-signature"><code>resolve_video_params() -&gt; VideoParams</code></pre>
<p>Resolve top-level, nested, and <code>size</code> dimensions like vLLM-Omni.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.image_suffix"><code>fastvideo.entrypoints.openai.request_adapter.image_suffix</code></h2>
<pre class="doc-signature"><code>image_suffix(image_url: str) -&gt; str</code></pre>
<p>File suffix for a downloaded image; decoding inspects content, so this is only a hint.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.save_base64_image_to_path"><code>fastvideo.entrypoints.openai.request_adapter.save_base64_image_to_path</code></h2>
<pre class="doc-signature"><code>save_base64_image_to_path(base64_data: str, target_path: str) -&gt; str</code></pre>

<h2 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs</code></h2>
<pre class="doc-signature"><code>FastVideoArgs(model_path: str, mode: ExecutionMode = ExecutionMode.INFERENCE, workload_type: WorkloadType = WorkloadType.T2V, distributed_executor_backend: str = &#x27;mp&#x27;, enable_streaming_ipc_queues: bool = False, ray_placement_group: PlacementGroup | None = None, ray_runtime_env: RuntimeEnv | None = None, inference_mode: bool = True, trust_remote_code: bool = False, revision: str | None = None, num_gpus: int = 1, tp_size: int = -1, sp_size: int = -1, hsdp_replicate_dim: int = 1, hsdp_shard_dim: int = -1, dist_timeout: int | None = None, pipeline_config: PipelineConfig = PipelineConfig(), preprocess_config: PreprocessConfig | None = None, lora_path: str | None = None, lora_nickname: str = &#x27;default&#x27;, lora_strength: float = 1.0, lora_target_modules: list&#91;str&#93; | None = None, output_type: str = &#x27;pil&#x27;, attention_backend: str | None = None, dit_cpu_offload: bool = True, use_fsdp_inference: bool = False, dit_layerwise_offload: bool = True, text_encoder_cpu_offload: bool = True, image_encoder_cpu_offload: bool = True, vae_cpu_offload: bool = True, pin_cpu_memory: bool = True, h3_sequential_load: bool | None = None, h3_encoder_split: bool | None = None, h3_encoder_nodes: int = -1, h3_encoder_workers: int = 0, video_decode_backend: str = &#x27;h3-vae&#x27;, taeh3_checkpoint: str | None = None, taeh3_chunk_size: int = 5, h3_vae_nvfp4_decoder: str | None = None, lazy_module_load: bool | None = None, vae_parallel_decode: bool = False, vae_parallel_encode: bool = False, vae_parallel_decode_strategy: str | None = None, enable_torch_compile: bool = False, regional_compile: bool = False, enable_torch_compile_text_encoder: bool = False, enable_torch_compile_vae: bool = False, enable_torch_compile_audio_vae: bool = False, torch_compile_kwargs: dict&#91;str, Any&#93; = dict(), torch_compile_kwargs_dit: dict&#91;str, Any&#93; = dict(), torch_compile_kwargs_text_encoder: dict&#91;str, Any&#93; = dict(), torch_compile_kwargs_vae: dict&#91;str, Any&#93; = dict(), torch_compile_kwargs_audio_vae: dict&#91;str, Any&#93; = dict(), inference_torch_compile: bool = False, h3_vsa_fp4: dict&#91;str, Any&#93; = dict(), disable_autocast: bool = False, VSA_sparsity: float | None = None, VSA_tile_size: int | None = None, moba_config_path: str | None = None, moba_config: dict&#91;str, Any&#93; = dict(), master_port: int | None = None, enable_stage_verification: bool = True, prompt_txt: str | None = None, ltx2_vae_tiling: bool | None = None, ltx2_vae_spatial_tile_size_in_pixels: int | None = None, ltx2_vae_spatial_tile_overlap_in_pixels: int | None = None, ltx2_vae_temporal_tile_size_in_frames: int | None = None, ltx2_vae_temporal_tile_overlap_in_frames: int | None = None, ltx2_initial_latent_path: str | None = None, ltx2_audio_latent_path: str | None = None, refine_enabled: bool | None = None, refine_upsampler_path: str | None = None, refine_transformer_path: str | None = None, refine_lora_path: str | None = None, refine_num_inference_steps: int | None = None, refine_guidance_scale: float | None = None, refine_add_noise: bool | None = None, refine_noise_path: str | None = None, refine_audio_noise_path: str | None = None, ltx2_refine_enabled: bool = False, ltx2_refine_upsampler_path: str | None = None, ltx2_refine_transformer_path: str | None = None, ltx2_refine_lora_path: str | None = None, ltx2_refine_num_inference_steps: int = 3, ltx2_refine_guidance_scale: float = 1.0, ltx2_refine_add_noise: bool = True, ltx2_refine_noise_path: str | None = None, ltx2_refine_audio_noise_path: str | None = None, ltx2_legacy_native_noise_order: bool = False, ltx2_use_distilled_sigmas: bool = True, model_paths: dict&#91;str, str&#93; = dict(), model_loaded: dict&#91;str, bool&#93; = (lambda: &#123;&#x27;transformer&#x27;: True, &#x27;vae&#x27;: True, &#x27;upsampler&#x27;: True&#125;)(), override_text_encoder_safetensors: str | None = None, override_text_encoder_quant: QuantizationMethods = None, transformer_quant: Any | None = None, override_transformer_cls_name: str | None = None, init_weights_from_safetensors: str = &#x27;&#x27;, init_weights_from_safetensors_2: str = &#x27;&#x27;, override_pipeline_cls_name: str | None = None, boundary_ratio: float | None = 0.875)</code></pre>


<h3 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.is_output_rank"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.is_output_rank</code></h3>
<pre class="doc-signature"><code>is_output_rank: bool</code></pre>
<p>Whether this process may materialize user-facing outputs.</p>
<p>This is runtime state assigned by an SPMD executor, not a public
configuration field, so dataclass serialization and typed config
parsing deliberately ignore it.</p>
<h3 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.add_cli_args"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.add_cli_args</code></h3>
<pre class="doc-signature"><code>add_cli_args(parser: FlexibleArgumentParser) -&gt; FlexibleArgumentParser</code></pre>

<h3 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.from_cli_args"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.from_cli_args</code></h3>
<pre class="doc-signature"><code>from_cli_args(args: argparse.Namespace) -&gt; FastVideoArgs</code></pre>

<h3 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.from_kwargs"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.from_kwargs</code></h3>
<pre class="doc-signature"><code>from_kwargs(**kwargs: Any) -&gt; FastVideoArgs</code></pre>

<h3 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.check_fastvideo_args"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.check_fastvideo_args</code></h3>
<pre class="doc-signature"><code>check_fastvideo_args() -&gt; None</code></pre>
<p>Validate inference arguments for consistency</p>
<h3 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.finalize_device_offload_policy"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.finalize_device_offload_policy</code></h3>
<pre class="doc-signature"><code>finalize_device_offload_policy(device_id: int = 0) -&gt; bool</code></pre>
<p>Apply device-local memory policy, then resolve incompatible modes.</p>
<h3 id="fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.disable_offload_on_unified_memory"><code>fastvideo.entrypoints.openai.request_adapter.FastVideoArgs.disable_offload_on_unified_memory</code></h3>
<pre class="doc-signature"><code>disable_offload_on_unified_memory(device_id: int = 0, *, offload_flag: str | None = None) -&gt; bool</code></pre>
<p>Disable host offload after a worker has selected its device.</p>
<p>CUDA's unified-memory probe reads runtime device properties and may
initialize a CUDA context. Callers must therefore use this only inside
a device-owning process, after selecting and binding <code>device_id</code>.
Returning the classification lets direct component-loader callers
apply the same policy to explicit per-call overrides. When
<code>offload_flag</code> is given, the return value says whether this policy
covers that component role.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.load_image"><code>fastvideo.entrypoints.openai.request_adapter.load_image</code></h2>
<pre class="doc-signature"><code>load_image(image: str | PIL.Image.Image, convert_method: Callable&#91;&#91;PIL.Image.Image&#93;, PIL.Image.Image&#93; | None = None) -&gt; PIL.Image.Image</code></pre>
<p>Loads <code>image</code> to a PIL Image.</p>
<h3>Parameters</h3>
<dl>
<dt><code>image: `str` or `PIL.Image.Image`</code></dt><dd><p>The image to convert to the PIL Image format.</p></dd>
<dt><code>convert_method: Callable[[PIL.Image.Image], PIL.Image.Image], *optional*</code></dt><dd><p>A conversion method to apply to the image after loading it. When set to <code>None</code> the image will be converted
"RGB".</p></dd>
</dl>
<h3>Returns</h3>
<dl>
<dt><code>PIL.Image.Image</code></dt><dd><p><code>PIL.Image.Image</code>:
A PIL Image.</p></dd>
</dl>
<h2 id="fastvideo.entrypoints.openai.request_adapter.get_preset_selection"><code>fastvideo.entrypoints.openai.request_adapter.get_preset_selection</code></h2>
<pre class="doc-signature"><code>get_preset_selection(model_path: str) -&gt; tuple&#91;str | None, str | None&#93;</code></pre>
<p>Return <code>(default_preset, model_family)</code> for a model path.</p>
<p>Single-lookup variant of :func:<code>get_default_preset</code> +
:func:<code>get_model_family</code>; callers that need both should prefer this
to avoid walking the registry twice.</p>
<h2 id="fastvideo.entrypoints.openai.request_adapter.RequestAdaptationError"><code>fastvideo.entrypoints.openai.request_adapter.RequestAdaptationError</code></h2>
<pre class="doc-signature"><code>RequestAdaptationError()</code></pre>
<p>The transport request cannot be represented by the loaded pipeline.</p>
<details><summary>Source</summary><pre><code>class RequestAdaptationError(ValueError):
    &quot;&quot;&quot;The transport request cannot be represented by the loaded pipeline.&quot;&quot;&quot;</code></pre></details>
<h2 id="fastvideo.entrypoints.openai.request_adapter.discard_materialized_media"><code>fastvideo.entrypoints.openai.request_adapter.discard_materialized_media</code></h2>
<pre class="doc-signature"><code>discard_materialized_media(paths: list&#91;str&#93;) -&gt; None</code></pre>

<details><summary>Source</summary><pre><code>def discard_materialized_media(paths: list&#91;str&#93;) -&gt; None:
    for path in paths:
        discard(path)</code></pre></details>
<h2 id="fastvideo.entrypoints.openai.request_adapter.prepare_reference_media"><code>fastvideo.entrypoints.openai.request_adapter.prepare_reference_media</code></h2>
<pre class="doc-signature"><code>prepare_reference_media(request_id: str, request: VideoGenerationRequest, output_dir: str, *, max_bytes: int | None = None, policy: MediaPolicy | None = None) -&gt; list&#91;str&#93;</code></pre>
<p>Materialize media references and return the files created for this request.</p>
<details><summary>Source</summary><pre><code>async def prepare_reference_media(
    request_id: str,
    request: VideoGenerationRequest,
    output_dir: str,
    *,
    max_bytes: int | None = None,
    policy: MediaPolicy | None = None,
) -&gt; list&#91;str&#93;:
    &quot;&quot;&quot;Materialize media references and return the files created for this request.&quot;&quot;&quot;
    policy = get_media_policy() if policy is None else policy
    _image_sources(request)
    _video_sources(request)
    uploads_dir = os.path.join(os.path.abspath(output_dir), &quot;uploads&quot;)
    created: list&#91;str&#93; = &#91;&#93;

    def track(path: str) -&gt; str:
        if path not in created:
            created.append(path)
        return path

    def is_remote(source: str) -&gt; bool:
        return source.lower().startswith((&quot;http://&quot;, &quot;https://&quot;, &quot;data:image&quot;))

    async def materialize(source: str, index: int) -&gt; str:
        source = source.strip()
        if not source:
            raise RequestAdaptationError(&quot;Image references must not be empty.&quot;)
        target = os.path.join(uploads_dir, f&quot;&#123;request_id&#125;_&#123;index&#125;&quot;)
        if source.startswith(&quot;data:image&quot;):
            try:
                local_path = track(await save_base64_image_to_path(source, target))
            except Exception as error:
                raise RequestAdaptationError(f&quot;Unable to decode image reference: &#123;error&#125;&quot;) from error
        elif is_remote(source):
            local_path = track(await _materialize_image_url(source, target, max_bytes=max_bytes, policy=policy))
        else:
            local_path = _local_media(source, policy)
        try:
            await asyncio.to_thread(load_image, local_path)
        except Exception as error:
            raise RequestAdaptationError(f&quot;Unable to decode image reference: &#123;error&#125;&quot;) from error
        return local_path

    try:
        index = 0
        for reference in _as_list(request.image_reference):
            if isinstance(reference, UrlImageReference):
                reference.image_url = await materialize(reference.image_url, index)
                index += 1
        if request.input_reference:
            request.input_reference = await materialize(request.input_reference, index)
            index += 1
        elif request.input_reference == &quot;&quot;:
            request.input_reference = None
        if request.reference_url:
            request.reference_url = await materialize(request.reference_url, index)
        elif request.reference_url == &quot;&quot;:
            request.reference_url = None

        for index, reference in enumerate(_as_list(request.video_reference)):
            if isinstance(reference, UrlVideoReference):
                remote = is_remote(reference.video_url)
                reference.video_url = await _materialize_video(reference.video_url,
                                                               os.path.join(uploads_dir, f&quot;&#123;request_id&#125;_video_&#123;index&#125;&quot;),
                                                               max_bytes=max_bytes,
                                                               policy=policy)
                if remote:
                    track(reference.video_url)
        if request.video_path:
            remote = is_remote(request.video_path)
            request.video_path = await _materialize_video(request.video_path,
                                                          os.path.join(uploads_dir, f&quot;&#123;request_id&#125;_video_path&quot;),
                                                          max_bytes=max_bytes,
                                                          policy=policy)
            if remote:
                track(request.video_path)
        if request.video_url:
            remote = is_remote(request.video_url)
            request.video_url = await _materialize_video(request.video_url,
                                                         os.path.join(uploads_dir, f&quot;&#123;request_id&#125;_video_url&quot;),
                                                         max_bytes=max_bytes,
                                                         policy=policy)
            if remote:
                track(request.video_url)
    except BaseException:
        # Includes cancellation, so a disconnected client leaves no downloaded inputs behind.
        discard_materialized_media(created)
        raise
    return created</code></pre></details>
<h2 id="fastvideo.entrypoints.openai.request_adapter.validate_served_model_name"><code>fastvideo.entrypoints.openai.request_adapter.validate_served_model_name</code></h2>
<pre class="doc-signature"><code>validate_served_model_name(model: str | None, args: FastVideoArgs, served_model_name: str) -&gt; None</code></pre>
<p>Reject a request model id that is not the one this server loaded.</p>
<details><summary>Source</summary><pre><code>def validate_served_model_name(
    model: str | None,
    args: FastVideoArgs,
    served_model_name: str,
) -&gt; None:
    &quot;&quot;&quot;Reject a request model id that is not the one this server loaded.&quot;&quot;&quot;
    if model is None:
        return
    allowed_models = &#123;args.lora_nickname&#125; if args.lora_path else &#123;served_model_name&#125;
    if model not in allowed_models:
        choices = &quot;, &quot;.join(sorted(allowed_models))
        raise RequestAdaptationError(f&quot;Model mismatch: request specifies &#123;model!r&#125;; this server provides &#123;choices&#125;.&quot;)</code></pre></details>
<h2 id="fastvideo.entrypoints.openai.request_adapter.validate_model_and_lora"><code>fastvideo.entrypoints.openai.request_adapter.validate_model_and_lora</code></h2>
<pre class="doc-signature"><code>validate_model_and_lora(request: VideoGenerationRequest, args: FastVideoArgs, served_model_name: str) -&gt; None</code></pre>
<p>Validate vLLM-style model and LoRA selectors against startup state.</p>
<p>FastVideo's published FastH3 adapters include dense replacement tensors in
addition to low-rank factors. Those tensors are applied while the model is
loaded and cannot be swapped safely between concurrent requests. The API
accepts vLLM's selector shape, but it must identify the startup adapter.</p>
<details><summary>Source</summary><pre><code>def validate_model_and_lora(
    request: VideoGenerationRequest,
    args: FastVideoArgs,
    served_model_name: str,
) -&gt; None:
    &quot;&quot;&quot;Validate vLLM-style model and LoRA selectors against startup state.

    FastVideo&#x27;s published FastH3 adapters include dense replacement tensors in
    addition to low-rank factors. Those tensors are applied while the model is
    loaded and cannot be swapped safely between concurrent requests. The API
    accepts vLLM&#x27;s selector shape, but it must identify the startup adapter.
    &quot;&quot;&quot;
    validate_served_model_name(request.model, args, served_model_name)

    if request.lora is None:
        return
    if not args.lora_path:
        raise RequestAdaptationError(
            &quot;This server has no startup LoRA. Configure generator.pipeline.components.lora_path before using &quot;
            &quot;the request lora selector.&quot;)

    body = request.lora
    name = next((body&#91;key&#93; for key in (&quot;name&quot;, &quot;lora_name&quot;, &quot;adapter&quot;) if body.get(key) is not None), None)
    path = next((body&#91;key&#93; for key in (&quot;path&quot;, &quot;lora_path&quot;, &quot;local_path&quot;) if body.get(key) is not None), None)
    scale = next((body&#91;key&#93; for key in (&quot;scale&quot;, &quot;lora_scale&quot;) if body.get(key) is not None), None)
    if name is None and path is None:
        raise RequestAdaptationError(&quot;lora must provide a name or path&quot;)
    if name is not None and str(name) != args.lora_nickname:
        raise RequestAdaptationError(f&quot;Requested LoRA &#123;name!r&#125; is not the startup adapter &#123;args.lora_nickname!r&#125;.&quot;)
    if path is not None and str(path) != args.lora_path:
        raise RequestAdaptationError(
            f&quot;Requested LoRA path &#123;path!r&#125; does not match the startup adapter &#123;args.lora_path!r&#125;.&quot;)
    if scale is not None:
        try:
            scale_value = float(scale)
        except (TypeError, ValueError) as error:
            raise RequestAdaptationError(f&quot;Invalid LoRA scale &#123;scale!r&#125;&quot;) from error
        if not math.isclose(scale_value, args.lora_strength, rel_tol=0.0, abs_tol=1e-8):
            raise RequestAdaptationError(
                f&quot;Requested LoRA scale &#123;scale_value:g&#125; does not match startup strength &#123;args.lora_strength:g&#125;.&quot;)</code></pre></details>
<h2 id="fastvideo.entrypoints.openai.request_adapter.build_generation_request"><code>fastvideo.entrypoints.openai.request_adapter.build_generation_request</code></h2>
<pre class="doc-signature"><code>build_generation_request(request_id: str, request: VideoGenerationRequest, args: FastVideoArgs, *, served_model_name: str, output_dir: str, default_request: GenerationRequest | None = None) -&gt; GenerationRequest</code></pre>
<p>Build one tracked FastVideo request using explicit-field precedence.</p>
<details><summary>Source</summary><pre><code>def build_generation_request(
    request_id: str,
    request: VideoGenerationRequest,
    args: FastVideoArgs,
    *,
    served_model_name: str,
    output_dir: str,
    default_request: GenerationRequest | None = None,
) -&gt; GenerationRequest:
    &quot;&quot;&quot;Build one tracked FastVideo request using explicit-field precedence.&quot;&quot;&quot;
    validate_model_and_lora(request, args, served_model_name)
    workload_type = getattr(args, &quot;workload_type&quot;, &quot;&quot;)
    workload_value = str(getattr(workload_type, &quot;value&quot;, workload_type) or &quot;&quot;)
    is_audio = workload_value.endswith(&quot;2a&quot;)
    kwargs: dict&#91;str, Any&#93; = &#123;&#125;
    if default_request is not None:
        kwargs.update(explicit_request_updates(default_request))

    body_set = request.model_fields_set
    nested_set = request.video_params.model_fields_set if request.video_params is not None else set()
    if &quot;size&quot; in body_set and request.size is not None:
        width, height = request.size.split(&quot;x&quot;, 1)
        kwargs&#91;&quot;width&quot;&#93;, kwargs&#91;&quot;height&quot;&#93; = int(width), int(height)
    else:
        if &quot;width&quot; in body_set and request.width is not None:
            kwargs&#91;&quot;width&quot;&#93; = request.width
        elif &quot;video_params&quot; in body_set and &quot;width&quot; in nested_set and request.video_params.width is not None:
            kwargs&#91;&quot;width&quot;&#93; = request.video_params.width
        if &quot;height&quot; in body_set and request.height is not None:
            kwargs&#91;&quot;height&quot;&#93; = request.height
        elif &quot;video_params&quot; in body_set and &quot;height&quot; in nested_set and request.video_params.height is not None:
            kwargs&#91;&quot;height&quot;&#93; = request.video_params.height

    fps_explicit = (&quot;fps&quot; in body_set
                    and request.fps is not None) or (&quot;video_params&quot; in body_set and &quot;fps&quot; in nested_set
                                                     and request.video_params.fps is not None)
    if fps_explicit:
        fps = request.fps if &quot;fps&quot; in body_set else request.video_params.fps
        if fps is not None:
            kwargs&#91;&quot;fps&quot;&#93; = fps
    kwargs.setdefault(&quot;fps&quot;, 24)

    frames_explicit = (&quot;num_frames&quot; in body_set
                       and request.num_frames is not None) or (&quot;video_params&quot; in body_set and &quot;num_frames&quot; in nested_set
                                                               and request.video_params.num_frames is not None)
    if frames_explicit:
        num_frames = request.num_frames if &quot;num_frames&quot; in body_set else request.video_params.num_frames
        if num_frames is not None:
            kwargs&#91;&quot;num_frames&quot;&#93; = num_frames
    elif not is_audio and &quot;seconds&quot; in body_set and request.seconds is not None:
        kwargs&#91;&quot;num_frames&quot;&#93; = int(request.seconds) * int(kwargs&#91;&quot;fps&quot;&#93;)

    direct_fields = (
        &quot;seed&quot;,
        &quot;num_inference_steps&quot;,
        &quot;guidance_scale&quot;,
        &quot;guidance_scale_2&quot;,
        &quot;true_cfg_scale&quot;,
        &quot;negative_prompt&quot;,
        &quot;enable_teacache&quot;,
        &quot;max_sequence_length&quot;,
        &quot;boundary_ratio&quot;,
        &quot;audio_start_in_s&quot;,
        &quot;audio_end_in_s&quot;,
    )
    for name in direct_fields:
        if name in body_set:
            value = getattr(request, name)
            if value is not None:
                kwargs&#91;name&#93; = value
    if is_audio and &quot;seconds&quot; in body_set and request.seconds is not None and &quot;audio_end_in_s&quot; not in body_set:
        start = float(kwargs.get(&quot;audio_start_in_s&quot;) or 0.0)
        kwargs&#91;&quot;audio_start_in_s&quot;&#93; = start
        kwargs&#91;&quot;audio_end_in_s&quot;&#93; = start + float(int(request.seconds))
    if is_audio:
        if &#123;&quot;size&quot;, &quot;width&quot;, &quot;height&quot;, &quot;video_params&quot;&#125; &amp; body_set:
            raise RequestAdaptationError(&quot;Audio generation does not accept size, width, height, or video_params.&quot;)
        start = float(kwargs.get(&quot;audio_start_in_s&quot;) or 0.0)
        end = kwargs.get(&quot;audio_end_in_s&quot;)
        if end is not None and float(end) &lt;= start:
            raise RequestAdaptationError(f&quot;audio_end_in_s (&#123;end&#125;) must be greater than audio_start_in_s (&#123;start&#125;).&quot;)
    if &quot;n&quot; in body_set or &quot;num_outputs_per_prompt&quot; in body_set:
        kwargs&#91;&quot;num_videos_per_prompt&quot;&#93; = request.resolved_num_outputs

    try:
        _, model_family = get_preset_selection(args.model_path)
    except (RuntimeError, ValueError):
        model_family = None
    if request.resolved_num_outputs != 1:
        raise RequestAdaptationError(&quot;FastVideo serving currently supports exactly one video output per request.&quot;)
    if &quot;short_edge&quot; in body_set and request.short_edge is not None and request.aspect_ratio is None:
        raise RequestAdaptationError(&quot;short_edge requires aspect_ratio.&quot;)
    _apply_aspect_ratio(kwargs, request, model_family=model_family)
    _apply_reference_inputs(kwargs, request, args, model_family=model_family)
    if model_family == &quot;mmaudio&quot; and not workload_value.endswith(&quot;t2a&quot;) and not kwargs.get(&quot;video_path&quot;):
        raise RequestAdaptationError(&quot;MMAudio video-to-audio generation requires video_reference or video_path.&quot;)

    extension_fields = (&quot;flow_shift&quot;, &quot;sound_duration&quot;, &quot;start_time_seconds&quot;)
    for name in extension_fields:
        if name in body_set and getattr(request, name) is not None:
            kwargs&#91;name&#93; = getattr(request, name)
    if &quot;generate_sound&quot; in body_set and request.generate_sound and model_family != &quot;minimax_h3&quot;:
        kwargs&#91;&quot;generate_sound&quot;&#93; = True
    if &quot;enable_frame_interpolation&quot; in body_set and request.enable_frame_interpolation:
        kwargs&#91;&quot;enable_frame_interpolation&quot;&#93; = True
        for name in (
                &quot;frame_interpolation_exp&quot;,
                &quot;frame_interpolation_scale&quot;,
                &quot;frame_interpolation_model_path&quot;,
        ):
            kwargs&#91;name&#93; = getattr(request, name)
    if request.extra_params:
        unknown_extra_params = sorted(set(request.extra_params) - set(REQUEST_BATCH_EXTRA_PASSTHROUGH_FIELDS))
        if unknown_extra_params:
            raise RequestAdaptationError(&quot;Unsupported extra_params fields: &quot; + &quot;, &quot;.join(unknown_extra_params))
        kwargs.update(request.extra_params)

    width = kwargs.get(&quot;width&quot;)
    height = kwargs.get(&quot;height&quot;)
    if width is not None and (not isinstance(width, int) or width &lt;= 0):
        raise RequestAdaptationError(f&quot;width must be a positive integer, got &#123;width!r&#125;&quot;)
    if height is not None and (not isinstance(height, int) or height &lt;= 0):
        raise RequestAdaptationError(f&quot;height must be a positive integer, got &#123;height!r&#125;&quot;)

    if model_family == &quot;minimax_h3&quot;:
        from fastvideo.pipelines.basic.minimax_h3.packing import (
            MINIMAX_H3_CANVAS_MULTIPLE,
            MINIMAX_H3_MAX_PIXELS,
        )
        from fastvideo.pipelines.basic.minimax_h3.stages.minimax_h3_input_preparation import (
            resolve_target_num_frames, )

        if kwargs&#91;&quot;fps&quot;&#93; != 24:
            raise RequestAdaptationError(f&quot;MiniMax-H3 requires fps=24, got &#123;kwargs&#91;&#x27;fps&#x27;&#93;&#125;.&quot;)
        if width is None or height is None:
            raise RequestAdaptationError(&quot;MiniMax-H3 requires both width and height.&quot;)
        if width % MINIMAX_H3_CANVAS_MULTIPLE or height % MINIMAX_H3_CANVAS_MULTIPLE:
            raise RequestAdaptationError(&quot;MiniMax-H3 width and height must be positive multiples of &quot;
                                         f&quot;&#123;MINIMAX_H3_CANVAS_MULTIPLE&#125;, got &#123;width&#125;x&#123;height&#125;.&quot;)
        if width * height &gt; MINIMAX_H3_MAX_PIXELS:
            raise RequestAdaptationError(
                f&quot;MiniMax-H3 canvas exceeds the &#123;MINIMAX_H3_MAX_PIXELS&#125;-pixel limit: &#123;width&#125;x&#123;height&#125;.&quot;)
        try:
            requested_num_frames = kwargs.get(&quot;num_frames&quot;)
            aligned_num_frames = resolve_target_num_frames(requested_num_frames)
        except (TypeError, ValueError) as error:
            raise RequestAdaptationError(str(error)) from error
        if frames_explicit and aligned_num_frames != requested_num_frames:
            raise RequestAdaptationError(&quot;MiniMax-H3 num_frames must be on the causal-VAE grid (17 * n + 5); &quot;
                                         f&quot;got &#123;requested_num_frames&#125;, next valid value is &#123;aligned_num_frames&#125;.&quot;)
        kwargs&#91;&quot;num_frames&quot;&#93; = aligned_num_frames

    media_dir = &quot;audio&quot; if is_audio else &quot;videos&quot;
    extension = &quot;.wav&quot; if is_audio else &quot;.mp4&quot;
    output_path = os.path.join(os.path.abspath(output_dir), media_dir, f&quot;&#123;request_id&#125;&#123;extension&#125;&quot;)
    os.makedirs(os.path.dirname(output_path), exist_ok=True)
    kwargs.update(&#123;
        &quot;output_path&quot;: output_path,
        &quot;save_video&quot;: True,
        &quot;return_frames&quot;: False,
    &#125;)
    generation_request = legacy_generate_call_to_request(request.prompt, None, legacy_kwargs=kwargs)
    try:
        # Resolve once at admission time so unsupported model-specific fields
        # are a deterministic 400, rather than an asynchronous failed job.
        request_to_sampling_param(generation_request, model_path=args.model_path)
    except (TypeError, ValueError) as error:
        raise RequestAdaptationError(str(error)) from error
    return generation_request</code></pre></details>
</div>
