Seedance Video Generation

Seedance 2.0 video generation and asset library API reference.

Overview Video Generation Request Parameters Asset Library Recommended Workflow

Base URL & Authentication

All requests use the unified Base URL with your API key in the Authorization header.

Base URL

https://api.onekeymodel.com/v1

Authorization Header Format

Authorization: Bearer YOUR_API_KEY

Supported Models

The following Seedance 2.0 models are available via the video generation API:

seedance2_0seedance2_0_fastseedance2_0_mini

Video Generation API

Video generation is a two-step process: submit a task and poll for results. Via the gateway, Seedance parameters go in metadata; prompt is auto-converted to a content text item.

Step 1: Create Video TaskPOST /v1/video/generations

Submit generation parameters. Returns a task record with an id.

Text-to-Video

bash

curl -X POST https://api.onekeymodel.com/v1/video/generations \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{
    "model": "seedance2_0",
    "prompt": "一只猫在海边奔跑，电影感镜头，阳光，慢动作",
    "metadata": {
      "ratio": "16:9",
      "duration": 5,
      "resolution": "720p",
      "generate_audio": true,
      "bitrate_mode": "standard",
      "watermark": false
    }
  }'

Image-to-Video

bash

curl -X POST https://api.onekeymodel.com/v1/video/generations \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{
    "model": "seedance2_0",
    "prompt": "让图片中的人物向镜头微笑并挥手",
    "metadata": {
      "content": [
        {
          "type": "image_url",
          "image_url": { "url": "https://example.com/input.png" },
          "role": "first_frame"
        }
      ],
      "ratio": "adaptive",
      "duration": 5,
      "resolution": "720p",
      "watermark": false
    }
  }'

Using asset:// from library

bash

curl -X POST https://api.onekeymodel.com/v1/video/generations \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{
    "model": "seedance2_0",
    "prompt": "基于参考素材生成一段产品展示视频",
    "metadata": {
      "content": [
        {
          "type": "image_url",
          "image_url": { "url": "asset://Asset-2026xxxx" },
          "role": "reference_image"
        }
      ],
      "ratio": "16:9",
      "duration": 5,
      "resolution": "720p"
    }
  }'

Response Example

json

{ "id": "task_xxx" }

Step 2: Query Video TaskGET /v1/video/generations/:task_id

Poll using the returned id every few seconds. When status becomes SUCCESS, retrieve the video URL from result_url.

bash

curl -X GET "https://api.onekeymodel.com/v1/video/generations/task_xxx" \
  -H "Authorization: Bearer $YOUR_API_KEY"

Response Example

json

{
  "code": "success",
  "data": {
    "task_id": "task_xxx",
    "status": "SUCCESS",
    "result_url": "https://example.com/video.mp4"
  }
}

Request Parameters

Via the OneKeyModel gateway, place parameters in metadata except model and prompt.

The gateway appends prompt as a type=text item in content. If metadata.content is provided, prompt is still appended as text.

Request Parameters

Parameter	Type	Required	Description
model	string	Yes	Model name. Supports seedance2_0, seedance2_0_fast, seedance2_0_mini
prompt	string	Yes	Text prompt. Gateway auto-converts to type=text in content
metadata.content	array	No	Input content array for image, video, and audio assets
metadata.generate_audio	boolean	No	Whether to generate audio
metadata.bitrate_mode	string	No	Bitrate mode, e.g. standard, high
metadata.resolution	string	No	Output resolution, e.g. 480p, 720p, 1080p, 4k. Model-dependent
metadata.ratio	string	No	Aspect ratio. Common: 21:9, 16:9, 4:3, 1:1, 3:4, 9:16, adaptive
metadata.duration	integer	No	Video duration, typically 4–15 seconds
metadata.watermark	boolean	No	Whether to include watermark

content Array Elements

content is an array for image, video, and audio assets. Use asset:// URLs for library assets.

json

// Image
{ "type": "image_url", "image_url": { "url": "https://example.com/image.png" }, "role": "reference_image" }

// Video
{ "type": "video_url", "video_url": { "url": "https://example.com/video.mp4" }, "role": "reference_video" }

// Audio
{ "type": "audio_url", "audio_url": { "url": "https://example.com/audio.mp3" }, "role": "reference_audio" }

// Asset library
{ "type": "image_url", "image_url": { "url": "asset://Asset-2026xxxx" }, "role": "reference_image" }

Common role Values

role	Description
first_frame	First frame image
last_frame	Last frame image
reference_image	Reference image
reference_video	Reference video
reference_audio	Reference audio

Task Status

status	Description
QUEUED	Queued or submitted
IN_PROGRESS	In progress
SUCCESS	Succeeded
FAILURE	Failed

Asset Library API

Unified endpoint with Action parameter. Version is optional, defaults to 2024-01-01.

Unified EndpointPOST /v1/seedance_asset

https://api.onekeymodel.com/v1/seedance_asset?Action={Action}&Version=2024-01-01

Common Parameters

Parameter	Type	Required	Description
Action	query	Yes	Asset operation name (query). Lowercase action also supported
Version	query	No	OpenAPI version, default 2024-01-01. Lowercase version also supported
ProjectName	body	No	Ark project name, optional (body)

Supported Actions

CreateAssetGroupCreateAssetListAssetGroupsListAssetsGetAssetGetAssetGroupUpdateAssetGroupUpdateAssetDeleteAssetDeleteAssetGroup

CreateAssetGroup — Create Asset Group

Create an asset group to organize uploaded assets.

bash

curl -X POST "https://api.onekeymodel.com/v1/seedance_asset?Action=CreateAssetGroup&Version=2024-01-01" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{
    "Name": "seedance-demo-group",
    "Description": "Seedance demo assets",
    "GroupType": "AIGC"
  }'

CreateAsset — Create Asset

Create an asset from a URL. Assets typically enter Processing state and become usable after completion.

bash

curl -X POST "https://api.onekeymodel.com/v1/seedance_asset?Action=CreateAsset&Version=2024-01-01" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{
    "GroupId": "group-2026xxxx",
    "URL": "https://example.com/input.png",
    "Name": "demo-image",
    "AssetType": "Image",
    "Moderation": { "Strategy": "Skip" }
  }'

json

{ "Result": { "Id": "Asset-2026xxxx" } }

ListAssetGroups — List Asset Groups

Query asset groups with pagination.

bash

curl -X POST "https://api.onekeymodel.com/v1/seedance_asset?Action=ListAssetGroups&Version=2024-01-01" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{
    "Filter": { "GroupType": "AIGC" },
    "PageNumber": 1,
    "PageSize": 10,
    "SortBy": "CreateTime",
    "SortOrder": "Desc"
  }'

ListAssets — List Assets

Query assets with pagination, filterable by group and status.

bash

curl -X POST "https://api.onekeymodel.com/v1/seedance_asset?Action=ListAssets&Version=2024-01-01" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{
    "Filter": {
      "GroupType": "AIGC",
      "GroupIds": ["group-2026xxxx"],
      "Statuses": ["Active"]
    },
    "PageNumber": 1,
    "PageSize": 10,
    "SortBy": "CreateTime",
    "SortOrder": "Desc"
  }'

GetAsset — Get Asset Details

Retrieve asset details by Asset ID.

bash

curl -X POST "https://api.onekeymodel.com/v1/seedance_asset?Action=GetAsset&Version=2024-01-01" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $YOUR_API_KEY" \
  -d '{ "Id": "Asset-2026xxxx" }'

Asset Status

Status	Description
Active	Ready for video generation
Processing	Preprocessing, not yet usable
Failed	Processing failed

Also supports GetAssetGroup, UpdateAssetGroup, UpdateAsset, DeleteAsset, DeleteAssetGroup.

Recommended Workflow

Typical flow combining asset library and video generation:

1. Create an asset group (CreateAssetGroup)
2. Upload assets (CreateAsset), wait for Active status, obtain Asset ID
3. Submit video task and poll until the final video URL is available