Seedance 2.5 First & Last Frame
seedance-2.5-first-last-frame-480pCommercial useSeedance 2.5 first/last-frame generates a smooth transition between opening and closing keyframes. Requires both first_frame_url and last_frame_url with aspect_ratio set to adaptive. Cannot be combined with reference_* fields.
Provide both first_frame_url and last_frame_url with aspect_ratio adaptive. Does not support reference_* video/audio fields.
First-frame image URL or asset://{assetId}. Mutually exclusive with reference_* fields.
Last-frame image URL or asset://{assetId}. Requires first_frame_url.
Portrait-library route: ingest hint for first_frame_url. Default skip (direct URL). Use virtual/real to upload portraits to the asset library.
Portrait-library route: ingest hint for last_frame_url. Default skip (direct URL). Use virtual/real to upload portraits to the asset library.
Text prompt describing the transition and motion.
Generate synchronized audio with the video.
Return the generated video's last frame. Cannot be true when draft=true.
Output video resolution.
Must be adaptive — the direct route follows the input image aspect ratio for keyframe-driven tasks.
Video duration from 4 to 30 seconds, or -1 for automatic selection.
Video output format.
Enable online search for the generation.
Enable content safety checking.