Videos

Accepted as mode too; if both are sent, model wins. An unknown value fails with invalid_model.

Required for every model except kling-motion, lipsync and genjutsu. Over the model's max_prompt_chars the request is rejected.

Length in seconds, as a string, from the model's durations in GET /models/; anything else is rejected and an omitted value takes the model default. Send it as a string: a JSON number passes the check but the model then renders its default length. Ignored where the length comes from an input: kling-motion, lipsync, genjutsu, gemini-omni-video when video1 is sent, and seedance25 in seedance_mode: edit.

One of 480, 720, 1080, 4k, per model, from its qualities in GET /models/; anything else is rejected and an omitted value takes the model default. Send it as a string, as with duration. kling is 1080-only and lipsync takes only auto.

Per-model set from GET /models/. image makes the output follow the input image where supported (sent upstream as auto or adaptive). Anything outside the model's set is rejected; an omitted value takes the model default.

Selects the variant within a model family, and with it the price.

A value outside the model's set is rejected. Send it as a string: a JSON number such as 2.6 is not read and the default is used. lipsync at v2-pro needs a video input; v3 takes either one video or one image. genjutsu at lite takes a reference video of at most 15 s. seedance2 renders 1080 and 4k only at pro; asking for them at another level is rejected rather than quietly lowered.

veo3 only. Derived from the number of input images when omitted: none → text-to-video; one → first-frame-last-frame, with the image as the first frame; two or three → image-to-video, with the images as references. Send first-frame-last-frame explicitly to use two images as the first and last frame. image-to-video takes 1 to 3 images and first-frame-last-frame 1 or 2.

seedance2 and seedance25 only. Derived when omitted: no images → text-to-video; one image → image-to-video; two images → first-frame-last-frame on seedance2 but reference-to-video on seedance25; three or more images, or any video1/audio1 → reference-to-video.

reference-to-video is the multimodal scene and needs at least one image or video. Limits:

edit and extend are seedance25 only and need at least one input video. In edit the output follows the input footage, so duration, aspect ratio and mode come from it, and every input video must be at least 4 s; it holds twice the input seconds plus 3 s at the with-video rate. extend continues the footage and charges the input plus the requested duration. Both settle on delivery to the input plus the delivered seconds.

seedance2 and seedance25. The price is identical either way, so leaving it on never costs extra.

No longer has any effect. seedance2 text-to-video requests always ground the scene in a web lookup.

seedance25 only.

lipsync only. How a video and an audio of different lengths are matched: bounce plays the video back and forth, loop repeats it, cut_off trims the longer one, silence pads the audio with silence, and remap changes the video speed. The price follows the output length: the audio length, except the longer of the two with silence and the shorter with cut_off.

kling-motion. Which source sets the character's facing. image limits the reference video to 10 s.

kling-motion at model_level: 3.0 only. Which source provides the background.

Hosted input images, https:// only and not on Hoosha media hosts; they are handed to the provider as-is. They fill the lowest free image1…imageN slots: if you sent only image2, the first URL becomes image1. They count toward the model's image cap.

Input image: an upload id (/videos/ reads upload ids only from these positional fields, not from uploads), or a file part in multipart (png, jpg, jpeg, webp or gif, at most 10,000,000 bytes, not converted). Continue with image2, image3, …

How many images each model reads: seedance25 30, seedance2 9, genjutsu 8 (at least 1 required), grok-imagine 7, gemini-omni-video 7 (5 when video1 is sent), veo3 3, kling3 1, kling-motion exactly 1, lipsync 1 when no video1 is sent (ignored with one), runway and seedance only image1. On kling, image2 is the end frame. Only grok-imagine and genjutsu reject extra images with too_many_images; elsewhere images beyond the limit are dropped. For first-frame-last-frame, image1 is the first frame and image2 the last.

Reference video, as an upload id. Required by kling-motion (3–30 s), by genjutsu (5–30 s, 5–15 s on lite, at most 200 MB) and by lipsync at model_level: v2-pro; optional on v3, which falls back to image1. gemini-omni-video reads video1 only (at most 10 s and 100 MB). seedance25 reference scenes take up to video10 and seedance2 up to video3.

Reference audio, as an upload id. Required by lipsync, where its length (2–30 s, 2–15 s with an image) sets the bill and files over 10 MB are rejected. seedance25 reference scenes take up to audio10 and seedance2 up to audio3.