Video Modes, Assets, and Prompt Optimization
The Video page only displays modes and parameters supported by the current model. After switching models, review the mode, media, and estimated credits again.
Creative mode
Uses the video description as the primary input and is suitable for starting from an idea. You can add reference images, videos, audio, and person assets when supported by the current model.
First/Last Frame mode
Uses a first-frame image as the start of the new video. The last frame is optional. You can upload images or extract a selected point from a video as the first or last frame.
The aspect ratio may be locked to the first frame, so choose the first frame before reviewing the remaining settings.
Edit and Extend
Edit or Extend only appears when supported by the current model. Both require a source video. After reading source metadata, the page locks duration or aspect ratio values determined by that source.
Review the settings again after replacing the source. Do not treat a compatibility preview as proof of original quality. When Download Original is available, use that result as the source of truth.
Reference media
- Reference images, videos, and audio: entry points and limits depend on the current model.
- Person assets: media containing a real person should use the person asset flow instead of being added only as an ordinary reference image.
- Seedance and Doubao person assets: register or create the asset on the Assets page before selecting it on Video Generation.
- Asset mentions: type
@in the prompt and select an asset that has already been chosen.
Switching models or providers may remove incompatible assets. Before submitting, review thumbnails, names, and mention markers again.
Prompt optimization
Supported models display Optimize Prompt. The page obtains a quote first and explains the reserved amount, maximum charge, and available balance. The final cost follows the server settlement result.
The optimized text is shown as a candidate and does not automatically replace the main prompt. Before applying it, check that:
- person and asset mentions remain complete;
- structural markers remain intact;
- the main prompt, model, and assets did not change during optimization.
If the context changed, the page blocks the old candidate. Start a new optimization against the latest content instead of carrying old asset relationships into a new task.
Drafts and devices
The Video form stores its main settings in the current browser. Drafts do not automatically sync to another device or browser and are lost when local browser data is cleared.
Next steps
View Video Results and History