> ## Documentation Index > Fetch the complete documentation index at: https://docs.imini.ai/llms.txt > Use this file to discover all available pages before exploring further. # Seedance 2.0 Fast > Seedance 2.0 Fast video generation model (with or without audio). A lightweight, faster variant of Seedance 2.0 with identical capabilities and parameters. ## OpenAPI ````yaml /en/openapi/videos/seedance-2-0-fast.yaml POST /v1/videos/generate openapi: 3.1.0 info: title: Seedance 2.0 Fast version: '1.0' description: >- Seedance 2.0 Fast video generation model (with or without audio). A lightweight, faster variant of Seedance 2.0 with identical parameters and capabilities. servers: - url: https://openapi.imini.ai/imini/router security: - ApiKeyAuth: [] paths: /v1/videos/generate: post: summary: Seedance 2.0 Fast description: > Submit an asynchronous video generation task. You will need to poll the query endpoint to retrieve the result. > Model ID: `doubao/seedance-2.0-fast` · Underlying: Seedance 2.0 Fast Capabilities, parameters, and input modes are identical to `doubao/seedance-2.0`, but generation is faster and cheaper — ideal for use cases where inference latency matters. **Supported input modes**: - **Text-to-video**: pass `prompt` only - **Image-to-video (first frame)**: 1 image with `first_frame` - **Image-to-video (first + last frame)**: 1 `first_frame` + 1 `last_frame` - **Multimodal reference-to-video**: any combination of reference images (1–9 with `reference_type=asset`) + reference videos (0–3 clips) + reference audios (0–3 clips); audio cannot be used alone > The three scenarios (first frame / first + last frame / multimodal reference) are **mutually exclusive** and cannot be mixed. operationId: generateSeedance20Fast requestBody: required: true content: application/json: schema: type: object required: - model properties: model: type: string description: Fixed value `doubao/seedance-2.0-fast`. prompt: type: string description: > The prompt. Supports Chinese, English, Japanese, Indonesian, Spanish, and Portuguese. > We recommend ≤ 500 Chinese characters or ≤ 1000 English words; overly long prompts may cause the model to ignore some details. example: >- A slow pan across a misty mountain valley at sunrise, cinematic resolution: type: string description: Output resolution. Defaults to `720P`. default: 720P enum: - 480P - 720P aspect_ratio: type: string description: > Output aspect ratio. Defaults to `adaptive` (auto-adapted by the model based on the input assets or prompt). default: adaptive enum: - '16:9' - '4:3' - '1:1' - '3:4' - '9:16' - '21:9' - adaptive duration: type: integer description: >- Video duration in seconds. Defaults to `5`; integer in the range `4 ~ 15`. default: 5 minimum: 4 maximum: 15 generate_audio: type: boolean description: >- Whether to generate audio in sync with the video. Defaults to `true`. Generated audio is mono. default: true reference_images: type: array description: > Reference image list. Up to **9** images. The input mode is determined by the `reference_type` combination: - **Image-to-video (first frame)**: 1 `first_frame` - **Image-to-video (first + last frame)**: 1 `first_frame` + 1 `last_frame` - **Multimodal reference-to-video**: 1–9 with `asset`; may be combined with `reference_videos` / `reference_audios` > Image requirements: formats `jpeg` / `png` / `webp` / `bmp` / `tiff` / `gif`; ≤ 30 MB per image; total request body ≤ 64 MB (avoid base64 for large files); width/height 300–6000 px; aspect ratio between 1:2.5 and 2.5:1. maxItems: 9 items: type: object required: - url properties: url: type: string description: > Image address, in one of two forms: **1)** A publicly accessible URL (`http://` or `https://`); **2)** A Data URI base64 encoding (starting with `data:image/`). reference_type: type: string description: | Reference type: - `asset` — multimodal reference (default) - `first_frame` — first frame - `last_frame` — last frame default: asset enum: - asset - first_frame - last_frame reference_videos: type: array description: > Reference video list. Up to **3** clips; total duration across all videos ≤ 15 seconds; public URL only. > Video requirements: formats `mp4` / `mov`; resolution 480P / 720P; 2–15 seconds per clip, ≤ 50 MB each; width/height 300–6000 px; aspect ratio between 1:2.5 and 2.5:1; pixel-product range [640×640, 834×1112]; FPS 24–60. maxItems: 3 items: type: object required: - url properties: url: type: string description: >- Publicly accessible video URL. base64 is not supported. refer_type: type: string description: > Reference type. Currently only `base` (reference video) is supported. default: base enum: - base reference_audios: type: array description: > Reference audio list. Up to **3** clips; total duration across all audios ≤ 15 seconds. **Cannot be used alone** — must be accompanied by at least one `reference_image` or `reference_video`. > Audio requirements: formats `wav` / `mp3`; 2–15 seconds per clip, ≤ 15 MB each; total request body ≤ 64 MB (avoid base64 for large files). maxItems: 3 items: type: object required: - url properties: url: type: string description: > Audio address, in one of two forms: **1)** A publicly accessible URL (`http://` or `https://`); **2)** A Data URI base64 encoding (starting with `data:audio/`). refer_type: type: string description: > Reference type. Currently only `reference` (reference audio) is supported. default: reference enum: - reference extra_params: type: object description: > Supports Seedance's official extension parameters. All optional: - `seed` — integer in `[-1, 2^32-1]`. `-1` or omitted uses a random seed; the same seed yields similar (but not guaranteed identical) outputs. - `watermark` — boolean, defaults to `false`. Whether to add a watermark to the generated video. - `return_last_frame` — boolean, defaults to `false`. When enabled, you can retrieve the generated video's last-frame image (PNG, no watermark, same dimensions as the video) via the query endpoint, useful for chaining multiple continuous video segments. additionalProperties: true examples: Text to Video: summary: Text to Video value: model: doubao/seedance-2.0-fast prompt: >- A slow pan across a misty mountain valley at sunrise, cinematic resolution: 720P aspect_ratio: '16:9' duration: 5 Image to Video (first frame): summary: Image to Video - First Frame value: model: doubao/seedance-2.0-fast prompt: The mountain comes alive as birds fly past reference_images: - url: https://example.com/first.jpg reference_type: first_frame resolution: 720P aspect_ratio: adaptive duration: 5 Multimodal Reference: summary: Multimodal Reference (images + video + audio) value: model: doubao/seedance-2.0-fast prompt: >- The apple from [image 1] and the fruit-tea cup from [image 2], with background music reference_images: - url: https://example.com/apple.jpg reference_type: asset - url: https://example.com/cup.jpg reference_type: asset reference_videos: - url: https://example.com/reference.mp4 refer_type: base reference_audios: - url: https://example.com/bgm.mp3 refer_type: reference resolution: 720P aspect_ratio: adaptive duration: 6 generate_audio: true extra_params: seed: 42 watermark: false responses: '200': description: Submitted successfully (asynchronous mode) content: application/json: schema: type: object properties: task_id: type: string description: Unique task ID, used for subsequent polling example: task_2044275355061448704 model: type: string description: The model ID used for this task example: doubao/seedance-2.0-fast created_at: type: string description: Task creation time (ISO 8601) example: '2026-04-15T04:43:20.233Z' request_id: type: string description: Unique request ID example: 67e2e394-cf6f-4998-b293-ebf20d14dc26 '400': description: Validation Error (e.g. invalid parameter, invalid prompt) content: application/json: schema: type: object properties: error: type: object properties: code: type: string description: Error code example: INVALID_PARAMETER message: type: string description: Error message details example: >- reference_audios must be accompanied by at least one reference_image or reference_video status: type: integer description: HTTP status code example: 400 request_id: type: string description: Unique request identifier example: req_abc123 security: - ApiKeyAuth: [] components: securitySchemes: ApiKeyAuth: type: http scheme: bearer bearerFormat: API Key description: > Pass `Authorization: Bearer ` in the request header. Go to the [API Keys management page](https://imini.ai/api-keys) to create and manage API Keys. ````