LongCat Single Avatar

POST/v1/run

Longcat Single Avatar Image Audio To Video by sandbase-ai - advanced AI model for audio-to-video. Delivers high-quality results with fast inference, suitable for both creative and production workflows.

Request body

Submit an async generation request. The model field selects the model; other fields are model-specific input parameters.

stringmodelrequired

Model identifier. Set to meituan/longcat-single-avatar/image-audio-to-video.

Default: meituan/longcat-single-avatar/image-audio-to-video

stringpromptrequired

The prompt to guide the video generation.

Default: A person is talking naturally with natural expressions and movements.

stringimagerequired

The URL of the image to animate.

Optional<string>audio

The URL of the audio file to drive the avatar.

Optional<string>resolution

Resolution of the generated video (480p or 720p). Billing is per video-second (16 frames): 480p is 1 unit per second and 720p is 4 units per second.

Allowed values: 480p, 720p

Default: 480p

Optional<number>audio_guidance_scale

The audio guidance scale. Higher values may lead to exaggerated mouth movements.

Range: 1 to 10

Default: 4

Optional<number>text_guidance_scale

The text guidance scale for classifier-free guidance.

Range: 1 to 10

Default: 4

Optional<integer>num_segments

Number of video segments to generate. Each segment adds ~5 seconds of video. First segment is ~5.8s, additional segments are 5s each.

Range: 1 to 10

Default: 1

Optional<integer>seed

The seed for the random number generator.

Optional<integer>num_inference_steps

Number of denoising or inference steps to run when supported.

Range: 10 to 100

Default: 50

Response Schema

The submit endpoint returns an accepted generation task. Poll the result endpoint with the returned id for terminal outputs or errors.

Optional<string>error

Error message if the task failed. Empty on success.

stringidrequired

Unique identifier for the generation task.

Optional<string>model

Model ID used for the prediction.

Optional<array>outputs

Array of generated content. Empty when status is not completed.

stringstatusrequired

Status of the task: pending, running, completed, failed, or timeout.

Allowed values: pending, running, completed, failed, timeout

Model capabilities

array<string>capability_tagsrequired

Capabilities declared by the model registry.

Default: audio-to-video

stringexecution_moderequired

Execution mode declared by the model registry.

Default: async

# 1. Submit a generation request
curl -X POST https://api.sandbase.ai/v1/run \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "meituan/longcat-single-avatar/image-audio-to-video",
  "prompt": "A person is talking naturally with natural expressions and movements.",
  "image": "https://raw.githubusercontent.com/meituan-longcat/LongCat-Video/refs/heads/main/assets/avatar/single/man.png",
  "audio": "https://raw.githubusercontent.com/meituan-longcat/LongCat-Video/refs/heads/main/assets/avatar/single/man.mp3"
}'

# 2. If the response is still running, poll the returned id
curl https://api.sandbase.ai/v1/run/run_abc123 \
  -H "Authorization: Bearer $SANDBASE_API_KEY"

Response202 Accepted

{
  "id": "run_abc123",
  "model": "meituan/longcat-single-avatar/image-audio-to-video",
  "status": "running",
  "outputs": []
}