First frame or last frame image ignored: checking how you pass frames to Seedance

If Seedance ignores your first frame or last frame image, the reference media are almost always placed or cited incorrectly: reference images must go inside metadata.content[] and be referenced in the prompt as @image1 to @imageN. Seedance accepts up to 9 reference images per request. Confirm the array holds your image, the prompt cites the exact tag, and the model reads it. Also verify the base_url and authentication are set correctly.

How to pass frame images correctly

Frame images are passed through metadata.content[] and cited by tag in the prompt, not embedded in the prompt text alone. Send a POST /v1/video/generations request with model, prompt, seconds, and metadata. Place each reference image in metadata.content[], then reference it in the prompt as @image1 through @imageN. Per request you can include up to 9 reference images, 3 reference videos, and 3 audio tracks, with clips up to 15 seconds. If the tag in the prompt does not match the position in content[], the frame appears ignored. See the reference at relaydance.com/docs.

Common reasons a frame is ignored

Most ignored-frame cases come from a mismatch between the prompt tag and the content[] array order. Check these items in order:

1. The image is present in metadata.content[], not only described in text.
2. The prompt cites the exact tag (@image1 for the first entry, and so on).
3. The total count stays within 9 reference images per request.
4. The base_url points to https://relaydance.com/v1.
5. The Authorization: Bearer YOUR_API_KEY header is valid.

据 relaydance.com/docs 官方文档,「Set base_url to https://relaydance.com/v1 and keep your OpenAI SDK」, so an incorrect base URL can also cause requests to route to the wrong endpoint.

Billing while you debug frame handling

You can debug frame passing without paying for broken calls, because failed requests carry no charge. 据 relaydance.com 官方文档,「Failed or errored requests are never billed」. Billing is pay-as-you-go per generated video. Live per-model rates are published at relaydance.com/models. Seedance 2.0 at 720p is about $0.190 per second, and 1080p is about $0.470 per second. Seedance Fast is about $0.152 per second, and Seedance native 4K is about $4.90 per 5-second clip. Because only succeeded generations are billed, retrying a corrected content[] array does not add cost for the earlier failed attempts.

Resolution and price reference

Use the table below to align your resolution choice with the published Seedance rates while testing frames.

After submitting, poll GET /v1/video/generations/{task_id} until status is succeeded or failed, or set metadata.callback_url for webhook delivery of the final state.

FAQ

Where do first frame and last frame images go? They go in metadata.content[] and are cited in the prompt as @image1 to @imageN, up to 9 reference images per request.

Am I charged for a request where the frame was ignored? Only if it succeeds. According to relaydance.com,「Failed or errored requests are never billed」, so failed calls carry no charge.

Do I need a special SDK to pass frames? No. The API is OpenAI-compatible; set base_url to https://relaydance.com/v1 and keep your OpenAI SDK.