> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crun.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Seedance Asset Upload API
> Upload custom image, video, and audio assets for Seedance workflows
## Overview
Use this endpoint when your Seedance workflow needs a reviewed asset ID instead of a direct public URL.
Typical cases:
* Real-person photos
* Realistic AI characters or avatars
* Any material that needs to enter the asset review process before generation
Only assets whose `Status` is `Active` can be used in Seedance generation requests.
## When Upload Is Required
| Asset type | Typical content | How to use |
| ------------------------ | ----------------------------------------------------------------------- | ------------------------------------------------------------- |
| Normal image | Landscapes, products, buildings, animals, cartoons, pure scene material | Use the public URL directly in the video generation request |
| Human face image | Photos containing a real person | Upload first, wait for review, then use the approved asset ID |
| Realistic humanoid image | AI characters, virtual idols, digital humans, realistic avatars | Upload first, wait for review, then use the approved asset ID |
## Flow
1. Prepare a publicly accessible resource URL.
2. Call [Seedance Asset Upload API](/models/seedance/asset-upload) with `name`, `asset_type`, and `asset_url`.
3. For real-person assets, first complete [Seedance Real-Person Asset Validation API](/models/seedance/visual-validate), then pass the returned `GroupId` as `group_id`.
4. If the upload succeeds, the API returns an `asset_id`.
5. Asset requires review, wait until the review is approved before using it in generation. Call [Seedance Asset Info API](/models/seedance/asset-info) and keep polling until `Status` becomes `Active`.
6. Use the approved asset identifier in Seedance video generation requests, typically in the form `asset://xxx`.
## Request Example
```json theme={null}
{
"name": "fashion-model-front",
"asset_type": "Image",
"asset_url": "https://example.com/assets/fashion-model-front.jpg",
"group_id": "group-20260331145705-*****"
}
```
For non-real-person assets, omit `group_id`. For real-person assets, `group_id` must be the `GroupId` returned by the validation result endpoint.
## Response Example
```json theme={null}
{
"code": 200,
"message": "success",
"data": {
"AssetId": "asset-20260420153000-ab12c"
}
}
```
## Use Uploaded Assets In Seedance
After approval, pass the asset ID into the Seedance video generation endpoint:
* `img_urls`
* `last_frame_image`
* `reference_images`
* `reference_videos`
* `reference_audios`
## Related Resources
Query upload status and wait for the asset to become active
Get the Asset Group ID required for real-person asset uploads
Use uploaded image assets in image-to-video requests
Use uploaded image, video, and audio assets in reference-to-video requests
## OpenAPI
````yaml models/seedance/asset-upload.json post /api/v1/client/job/asset-upload
openapi: 3.0.0
info:
title: Seedance Asset Upload API
description: >-
API documentation for uploading custom image, video, and audio assets used
by Seedance workflows
version: 1.0.0
contact:
name: Technical Support
email: support@crun.ai
servers:
- url: https://api.crun.ai
description: API Server
security:
- ApiKeyAuth: []
paths:
/api/v1/client/job/asset-upload:
post:
summary: Upload a custom asset for Seedance
description: Upload custom image, video, or audio assets for Seedance workflows.
operationId: seedance/asset-upload
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- name
- asset_type
- asset_url
properties:
name:
type: string
description: Display name of the asset.
minLength: 1
maxLength: 64
example: fashion-model-front
asset_type:
type: string
description: Type of asset being uploaded.
enum:
- Image
- Video
- Audio
example: Image
asset_url:
type: string
format: uri
description: >-
Publicly accessible asset URL. Image, video, and audio
uploads only support URL input; Base64 is not supported.
## Input Requirements
### General Rules
- When passing image, video, or audio materials, **only URLs
are supported**.
- **Base64 encoding is NOT supported**.
---
## Image Requirements
- **Formats**: jpeg, png, webp, bmp, tiff, gif, heic, heif
- **Aspect Ratio (width / height)**: (0.4, 2.5)
- **Dimensions (px)**: (300, 6000)
- **File Size**: less than 30 MB per image
---
## Video Requirements
- **Formats**: mp4, mov
- **Resolution**: 480p, 720p
- **Duration**: [2, 15] seconds
- **Dimensions**:
- Aspect Ratio (width / height): [0.4, 2.5]
- Width/Height (px): [300, 6000]
- Total Pixels: width × height ∈ [409600, 927408]
- **File Size**: ≤ 50 MB per video
- **Frame Rate (FPS)**: [24, 60]
---
## Audio Requirements
- **Formats**: wav, mp3
- **Duration**: [2, 15] seconds
- **File Size**: ≤ 15 MB per audio
example: https://example.com/assets/fashion-model-front.jpg
group_id:
type: string
nullable: true
description: >-
Optional Asset Group ID for real-person asset uploads. Get
this value from [Seedance Real-Person Asset Validation
API](/models/seedance/visual-validate) and pass it only when
uploading assets that should be bound to that validated real
person.
example: group-20260331145705-*****
example:
name: fashion-model-front
asset_type: Image
asset_url: https://example.com/assets/fashion-model-front.jpg
group_id: group-20260331145705-*****
responses:
'200':
description: Upload request accepted
content:
application/json:
schema:
allOf:
- $ref: '#/components/schemas/ApiResponse'
- type: object
properties:
data:
type: object
properties:
AssetId:
type: string
description: >-
Returned asset identifier. Query its status with
[Seedance Asset Info
API](/models/seedance/asset-info) and use it only
after `Status` becomes `Active`.
example: asset-20260420153000-ab12c
example:
code: 200
message: success
data:
AssetId: asset-20260420153000-ab12c
'422':
description: Validation Error
content:
application/json:
schema:
allOf:
- $ref: '#/components/schemas/ApiResponse'
- type: object
properties:
errors:
type: array
description: Detailed validation error messages
items:
type: string
example:
- Value error, asset upload failed
example:
code: 422
message: Asset upload failed. Please try other resources.
'500':
$ref: '#/components/responses/Error'
components:
schemas:
ApiResponse:
type: object
properties:
code:
type: integer
enum:
- 200
- 401
- 402
- 404
- 422
- 429
- 455
- 500
- 501
- 505
description: >-
Response status code
- **200**: Success - Request has been processed successfully
- **401**: Unauthorized - Authentication credentials are missing or
invalid
- **402**: Insufficient Credits - Account does not have enough
credits to perform the operation
- **404**: Not Found - The requested resource or endpoint does not
exist
- **422**: Validation Error - The request parameters failed
validation checks
- **429**: Rate Limited - Request limit has been exceeded for this
resource
- **455**: Service Unavailable - System is currently undergoing
maintenance
- **500**: Server Error - An unexpected error occurred while
processing the request
- **501**: Generation Failed - Content generation task failed
- **505**: Feature Disabled - The requested feature is currently
disabled
message:
type: string
description: Response message, error description when failed
example: success
responses:
Error:
description: Server Error
securitySchemes:
ApiKeyAuth:
type: apiKey
in: header
name: x-api-key
description: >-
All APIs require authentication via API Key.
Get API Key:
1. Visit [API Key Management Page](https://crun.ai/user-api-key) to get
your API Key
Usage:
Add to request header:
x-api-key: YOUR_API_KEY
Note:
- Keep your API Key secure and do not share it with others
- If you suspect your API Key has been compromised, reset it immediately
in the management page
````