Seedance 1.5 Pro I2V

Seedance 1.5 Pro supports audio-visual co-generation with multi-shot narrative, start/end frame control, and integrated audio output (voice, music, SFX).

POST /seedance-1.5-pro-i2v/async

cURL

basic

curl --request POST \
  --url https://api.modellix.ai/api/v1/bytedance/seedance-1.5-pro-i2v/async \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "first_frame_image": "https://example.com/image.jpg",
  "prompt": "The person smiles and waves"
}
'

200

{
  "code": 0,
  "message": "success",
  "data": {
    "status": "pending",
    "task_id": "task-abc123",
    "model_id": "model-123",
    "get_result": {
      "method": "GET",
      "url": "https://api.modellix.ai/api/v1/tasks/task-abc123"
    }
  }
}

Authorizations

Authorization · string · header · required

API Key authentication. Format: Bearer YOUR_API_KEY.

Body

application/json

At least one of first_frame_image or last_frame_image must be provided.

first_frame_image · string

URL or Base64 data for the first frame image.

Minimum string length: 1

Example:

"https://example.com/first.jpg"

last_frame_image · string

URL or Base64 data for the last frame image.

Minimum string length: 1

Example:

"https://example.com/last.jpg"

prompt · string

Description of the desired output.

Required string length: 1 - 2000

ratio · enum<string> · default: adaptive

Aspect ratio of the generated video.

Available options: 16:9, 4:3, 1:1, 3:4, 9:16, 21:9, adaptive

resolution · enum<string> · default: 720p

Output resolution of the video.

Available options: 480p, 720p, 1080p

duration · enum<integer> · default: 5

Video duration in seconds (4-12 seconds).

Available options: 4, 5, 6, 7, 8, 9, 10, 11, 12

seed · integer · default: -1

Random seed for reproducible generation. Use -1 for random.

Required range: -1 <= x <= 2147483647

camera_fixed · boolean · default: false

Whether to keep the camera fixed during generation.

generate_audio · boolean · default: true

Whether to generate audio. 1.5 Pro exclusive feature.

service_tier · enum<string> · default: default

Service tier for generation (e.g., default or flex).

Available options: default, flex

execution_expires_after · integer · default: 172800

Task expiration time in seconds.

Required range: 3600 <= x <= 259200

return_last_frame · boolean · default: false

Whether to return the last frame of the generated video.

Response

200 - application/json

Task submitted successfully

code · integer · required

Response code, 0 indicates success

Example:

0

message · string · required

Response message

Example:

"success"

data · object · required

Detailed data about the submitted asynchronous task.

Show child attributes