curl --request POST \
  --url https://api.evolink.ai/v1/videos/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "model": "seedance-2.5-flash-reference-to-video",
  "prompt": "Use the first-person perspective framing of @video1 throughout, and use @audio1 as background music throughout. First-person perspective fruit tea promotional video...",
  "image_urls": [
    "https://example.com/ref1.jpg",
    "https://example.com/ref2.jpg"
  ],
  "video_urls": [
    "https://example.com/reference.mp4"
  ],
  "audio_urls": [
    "https://example.com/bgm.mp3"
  ],
  "duration": 10,
  "quality": "720p",
  "aspect_ratio": "16:9",
  "generate_audio": true,
  "content_filter": true
}
'

{
  "created": 1761313744,
  "id": "task-unified-1774857405-abc123",
  "model": "seedance-2.5-flash-reference-to-video",
  "object": "video.generation.task",
  "progress": 0,
  "status": "pending",
  "task_info": {
    "can_cancel": false,
    "estimated_time": 165,
    "video_duration": 8
  },
  "type": "video",
  "usage": {
    "billing_rule": "per_second",
    "credits_reserved": 50,
    "user_group": "default"
  }
}

{
  "error": {
    "code": "invalid_parameter",
    "message": "Invalid request parameters",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid or expired token",
    "type": "authentication_error"
  }
}

{
  "error": {
    "code": "insufficient_quota",
    "message": "Insufficient quota. Please top up your account.",
    "type": "insufficient_quota"
  }
}

{
  "error": {
    "code": "model_access_denied",
    "message": "Token does not have access to model: seedance-2.5-flash-reference-to-video",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "rate_limit_exceeded",
    "message": "Too many requests, please try again later",
    "type": "rate_limit_error"
  }
}

{
  "error": {
    "code": "internal_error",
    "message": "Internal server error",
    "type": "api_error"
  }
}

{
  "error": {
    "code": "<string>",
    "message": "<string>",
    "type": "<string>"
  }
}

Seedance 2.5 Flash

Seedance 2.5 Flash Reference-to-Video

Generate video from a text prompt with optional reference images (0–10), videos (0–5), and audio clips (0–5). References may be omitted entirely, and audio-only reference input is supported.
Best suited for generating new footage: images, videos, and audio act as style, subject, camera-movement, and soundtrack references
To rewrite or continue an existing video, switch to Video Edit / Video Extend: once this model’s prompt carries an editing or extension intent, the request is validated as an edit / extend task — it is accepted without an error and the task only fails while it runs
Now supports AIGC realistic human materials
Asynchronous processing mode, use the returned task ID to query status
Generated video links are valid for 24 hours, please save them promptly

Draft limitation: Seedance 2.5 Flash does not support draft: true or draft-to-final conversion.

POST

videos

generations

curl --request POST \
  --url https://api.evolink.ai/v1/videos/generations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "model": "seedance-2.5-flash-reference-to-video",
  "prompt": "Use the first-person perspective framing of @video1 throughout, and use @audio1 as background music throughout. First-person perspective fruit tea promotional video...",
  "image_urls": [
    "https://example.com/ref1.jpg",
    "https://example.com/ref2.jpg"
  ],
  "video_urls": [
    "https://example.com/reference.mp4"
  ],
  "audio_urls": [
    "https://example.com/bgm.mp3"
  ],
  "duration": 10,
  "quality": "720p",
  "aspect_ratio": "16:9",
  "generate_audio": true,
  "content_filter": true
}
'

{
  "created": 1761313744,
  "id": "task-unified-1774857405-abc123",
  "model": "seedance-2.5-flash-reference-to-video",
  "object": "video.generation.task",
  "progress": 0,
  "status": "pending",
  "task_info": {
    "can_cancel": false,
    "estimated_time": 165,
    "video_duration": 8
  },
  "type": "video",
  "usage": {
    "billing_rule": "per_second",
    "credits_reserved": 50,
    "user_group": "default"
  }
}

{
  "error": {
    "code": "invalid_parameter",
    "message": "Invalid request parameters",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid or expired token",
    "type": "authentication_error"
  }
}

{
  "error": {
    "code": "insufficient_quota",
    "message": "Insufficient quota. Please top up your account.",
    "type": "insufficient_quota"
  }
}

{
  "error": {
    "code": "model_access_denied",
    "message": "Token does not have access to model: seedance-2.5-flash-reference-to-video",
    "type": "invalid_request_error"
  }
}

{
  "error": {
    "code": "rate_limit_exceeded",
    "message": "Too many requests, please try again later",
    "type": "rate_limit_error"
  }
}

{
  "error": {
    "code": "internal_error",
    "message": "Internal server error",
    "type": "api_error"
  }
}

{
  "error": {
    "code": "<string>",
    "message": "<string>",
    "type": "<string>"
  }
}

Authorizations

Authorization

string

header

required

##All endpoints require Bearer Token authentication##

Get API Key:

Visit the API Key Management Page to obtain your API Key

Add to request header:

Authorization: Bearer YOUR_API_KEY

Body

application/json

model

enum<string>

default:seedance-2.5-flash-reference-to-video

required

Video generation model name

Available options:

seedance-2.5-flash-reference-to-video

Example:

"seedance-2.5-flash-reference-to-video"

prompt

string

required

Text prompt describing the desired video. Supports both Chinese and English, recommended no more than 500 characters for Chinese. Maximum prompt length: 10000 tokens

Details:

When referring to input materials in the prompt, prefer explicit tags such as @image1, @video1, and @audio1 instead of relying only on natural-language references such as "image 1", "video 1", or "audio 1"
Tag numbers follow the order of the corresponding URL array and start at 1: the first image_urls item is @image1, the first video_urls item is @video1, and the first audio_urls item is @audio1
Natural-language numbering may still be understood, but explicit tags provide a clearer mapping between each material and its intended use

Avoid being classified as an edit / extend task:

The task type is inferred from the prompt intent: wording such as "edit the video", "add", "remove / delete", "change / replace" is treated as video editing; wording such as "extend forward / backward", "continue" is treated as video extension
Once classified as either task, aspect_ratio must be adaptive, and for video editing duration must be -1; otherwise the request is accepted without an error and the task later turns failed with error code InvalidParameter.TaskTypeConstraint. The pre-authorized quota is refunded, but the waiting time is wasted
If you really need editing / extension, use seedance-2.5-flash-video-edit or seedance-2.5-flash-video-extend instead: parameters are validated at submission, so invalid values return an immediate synchronous error
For pure reference generation, rephrase words like "replace" or "remove" descriptively, e.g. "the shot features ..." or "rendered in the style of @image1"

Example:

"Use the first-person perspective framing of @video1 throughout, and use @audio1 as background music throughout. First-person perspective fruit tea promotional video..."

image_urls

string<uri>[]

Reference image URL array, optional; 1–10 images when provided

Optional references: image_urls, video_urls, and audio_urls may all be omitted. Providing only audio_urls is also supported.

Role description:

Media Type	Role	Typical Usage
Image	`reference_image`	Style reference, product image, first/last frame (specified via prompt)

Image requirements:

Supported formats: .jpeg, .png, .webp
Aspect ratio (width/height): 0.4 ~ 2.5
Width/height pixels: 300 ~ 6000 px
Max size per image: 30MB
Total request body size must not exceed 64MB, do not use Base64 encoding
Image URLs must be directly accessible by the server

Media addresses: Publicly accessible HTTP(S) URLs and asset:// media IDs accessible to the selected upstream account are supported.

Maximum array length: 10

Example:

[
  "https://example.com/ref1.jpg",
  "https://example.com/ref2.jpg"
]

video_urls

string<uri>[]

Reference video URL array, optional; 1–5 videos when provided

Optional references: image_urls, video_urls, and audio_urls may all be omitted. Providing only audio_urls is also supported.

Role description:

Media Type	Role	Typical Usage
Video	`reference_video`	Camera movement reference, motion reference, original video for editing/extension

Video requirements:

Supported formats: .mp4, .mov
Resolution: 480p, 720p, 1080p, 4K
Duration per video: 2 ~ 30 seconds, max 5 videos, total duration of all videos ≤ 30 seconds
Aspect ratio (width/height): 0.4 ~ 2.5
Width/height pixels: 300 ~ 6000 px
Frame pixels (width × height): 409,600 ~ 8,295,044 (e.g., 640×640 ~ 3326×2494)
Max size per video: 200MB
Frame rate: 24 ~ 60 FPS
Total request body size must not exceed 64MB, do not use Base64 encoding
Specific codec, resolution, and other media validity checks are performed by the model
Using video references will increase costs (input video duration is counted in billing)
Video URLs must be directly accessible by the server

Media addresses: Publicly accessible HTTP(S) URLs and asset:// media IDs accessible to the selected upstream account are supported.

Maximum array length: 5

Example:

["https://example.com/reference.mp4"]

audio_urls

string<uri>[]

Reference audio URL array, optional; 1–5 clips when provided

Optional references: image_urls, video_urls, and audio_urls may all be omitted. Providing only audio_urls is also supported.

Role description:

Media Type	Role	Typical Usage
Audio	`reference_audio`	Background music, sound effects, voice/dialogue reference

Audio requirements:

Supported formats: .wav, .mp3
Duration per clip: 2 ~ 30 seconds, max 5 clips, total duration of all audio ≤ 30 seconds
Max size per clip: 15MB
Total request body size must not exceed 64MB, do not use Base64 encoding
Audio URLs must be directly accessible by the server

Media addresses: Publicly accessible HTTP(S) URLs and asset:// media IDs accessible to the selected upstream account are supported.

Maximum array length: 5

Example:

["https://example.com/bgm.mp3"]

duration

default:5

Output video duration (seconds), defaults to 5 seconds

Details:

Supports any integer value between 4–30 seconds
-1: automatic duration, the model picks a length within 4–30 seconds and billing follows the actual output length
Duration directly affects billing

If the prompt is classified as a video edit task, only -1 is accepted; an explicit number of seconds makes the task fail later, with no error at submission

Available options:

-1

Example:

10

quality

enum<string>

default:720p

Video resolution, defaults to 720p

Options:

480p: Lower clarity, lower cost
720p: Standard clarity, this is the default

Available options:

480p,

720p

Example:

"720p"

aspect_ratio

enum<string>

default:adaptive

Video aspect ratio, defaults to adaptive

Options:

16:9 (landscape), 9:16 (portrait), 1:1 (square), 4:3, 3:4, 21:9 (ultrawide)
adaptive: Determined based on prompt intent, priority: video > image > prompt

Pixel values per resolution:

Aspect Ratio	480p	720p
16:9	854×480	1280×720
4:3	752×560	1112×834
1:1	640×640	960×960
3:4	560×752	834×1112
9:16	480×854	720×1280
21:9	992×432	1470×630

If the prompt is classified as a video edit / extend task, only adaptive is accepted; a fixed ratio makes the task fail later, with no error at submission

Available options:

16:9,

9:16,

1:1,

4:3,

3:4,

21:9,

adaptive

Example:

"16:9"

generate_audio

boolean

default:true

Whether to generate synchronized audio, defaults to true

Options:

true: Video includes synchronized audio at no additional charge
false: Output silent video

Example:

true

content_filter

boolean

default:true

Content filter, enabled by default true

Options:

true: Standard content safety check, this is the default
false: Relaxes content restrictions, billed at +10% (1.1x). Illegal and prohibited content is always enforced regardless of this setting

Mutually exclusive with web search:

content_filter: false and model_params.web_search: true cannot be used together; sending both returns a 400 parameter error
Keep content_filter: true (the default) when web search is needed

Example:

true

output_format

enum<string>

default:mp4

Output container format, defaults to mp4

Options:

mp4: H.264 encoding with the best compatibility and standard color precision, this is the default
mov: H.264 + yuv444p chroma sampling + PCM audio for higher color fidelity, recommended for color grading, keying and compositing workflows. Browser inline playback may not support it; download and play with VLC / mpv / ffplay. No extra charge

Available options:

mp4,

mov

Example:

"mp4"

callback_url

string<uri>

HTTPS callback URL for task completion

Callback timing:

Triggered when the task is completed or failed
Sent after billing confirmation is complete

Security restrictions:

Only HTTPS protocol is supported
Callbacks to private IP addresses are prohibited (127.0.0.1, 10.x.x.x, 172.16-31.x.x, 192.168.x.x, etc.)
URL length must not exceed 2048 characters

Callback mechanism:

Timeout: 10 seconds
Up to 3 retries after failure (at 1/2/4 seconds after failure respectively)
Callback response body format is consistent with the task query endpoint response format
A 2xx status code is considered successful; other status codes trigger retries

Example:

"https://your-domain.com/webhooks/video-task-completed"

Response

Video generation task created successfully

created

integer

Task creation timestamp

Example:

1761313744

string

Task ID

Example:

"task-unified-1774857405-abc123"

model

string

Actual model name used

Example:

"seedance-2.5-flash-reference-to-video"

object

enum<string>

Specific type of the task

Available options:

video.generation.task

progress

integer

Task progress percentage (0-100)

Required range: 0 <= x <= 100

Example:

0

status

enum<string>

Task status

Available options:

pending,

processing,

completed,

failed

Example:

"pending"

task_info

object

Video task details

Show child attributes

type

enum<string>

Output type of the task

Available options:

text,

image,

audio,

video

Example:

"video"

usage

object

Usage and billing information

Show child attributes

Image Series

Video Series

Audio Series

Text Series

Account Management

Task Management

File Management

Seedance 2.5 Flash Reference-to-Video

Authorizations

Body

Response