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HeyGen Lipsync Speed

POST/v1/run

HeyGen v3 Lipsync (speed) replaces the speech in a video and re-syncs the speaker's lips to the new audio.

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 heygen/lipsync/speed.

Default: heygen/lipsync/speed

stringaudiorequired

Input audio URL.

Optional<boolean>disable_music_track

Remove background music from the source video.

Default: false

Optional<boolean>enable_caption

Burn in captions.

Default: false

Optional<boolean>enable_dynamic_duration

Allow the video length to follow the new audio.

Default: true

Optional<boolean>enable_speech_enhancement

Enhance the replacement audio.

Default: false

Optional<number>end_time

End time (seconds) for partial lipsync.

Minimum: 0

Optional<number>start_time

Start time (seconds) for partial lipsync.

Minimum: 0

stringvideorequired

Input video URL.

Response Schema

The submit endpoint returns a run response. If its status is pending or running, poll GET /v1/run/{id} with the returned opaque ID until it reaches a terminal state.

stringidrequired

Opaque SandBase run identifier. Use it exactly as returned; no prefix is guaranteed.

stringstatusrequired

Current public run status.

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

Optional<string>model

Public SandBase model name used for this run.

Optional<array<object>>outputs

Present only for completed runs. Each object is capability-specific; inspect the selected model schema for its fields.

Optional<object>error

Present only for failed or timeout runs. Contains a public error type and sanitized message.

Optional<string>error.type

Stable public error category.

Optional<string>error.message

Sanitized error message safe to show to clients.

Optional<object>usage

Usage details when available.

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