Wan 2.1 VACE Outpainting API Reference

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 alibaba/wan/2.1/vace/outpainting.

Default: alibaba/wan/2.1/vace/outpainting

stringpromptrequired

The text prompt to guide video generation.

Optional<string>aspect_ratio

The aspect ratio of the generated image.

Allowed values: 21:9, 16:9, 3:2, 4:3, 5:4, 1:1, 4:5, 3:4, 2:3, 9:16

Optional<string>video

URL to the source video file. Required for outpainting.

Optional<string>resolution

Resolution of the generated video.

Allowed values: auto, 240p, 360p, 480p, 720p

Default: auto

Optional<integer>seed

Random seed for reproducibility. If None, a random seed is chosen.

Optional<boolean>expand_left

Whether to expand the video to the left.

Default: false

Optional<boolean>expand_top

Whether to expand the video to the top.

Default: false

Optional<boolean>expand_right

Whether to expand the video to the right.

Default: false

Optional<number>expand_ratio

Amount of expansion. This is a float value between 0 and 1, where 0.25 adds 25% to the original video size on the specified sides.

Range: 0 to 1

Default: 0.25

Optional<boolean>expand_bottom

Whether to expand the video to the bottom.

Default: false

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: video-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": "alibaba/wan/2.1/vace/outpainting", "prompt": "A lone woman strides through the neon-drenched streets of Tokyo at night. Her crimson dress, a vibrant splash of color against the deep blues and blacks of the cityscape, flows slightly with each step. A tailored black jacket, crisp and elegant, contrasts sharply with the dress's rich texture. Medium shot: The city hums around her, blurred lights creating streaks of color in the background. Close-up: The fabric of her dress catches the streetlight's glow, revealing a subtle silk sheen and the intricate stitching at the hem. Her black jacket’s subtle texture is visible – a fine wool perhaps, with a matte finish. The overall mood is one of quiet confidence and mystery, a vibrant woman navigating a bustling, nocturnal landscape. High resolution 4k.", "aspect_ratio": "21:9", "video": "https://static.sandbase.ai/examples/alibaba/wan/2.1/vace/outpainting/input_video_0.mp4" }' # 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"