Start Frame

Start by adding your start image in the “Start Frame” section and your end image in the “End Frame” section. These two images define the beginning and end of your video clip.

WanVideo Cliplength & Start - End Ratio

Next, use the “num_frames” setting to define the total length of your clip — that is, how many frames will be generated in between. The “ratio” parameter controls how the transition is distributed: a value of 0.5 creates an even blend between start and end. A value below 0.5 means the start frame will linger longer, while a value above 0.5 keeps the end frame visible for a greater portion of the clip.

Prompt

In the “Prompt” field, describe what happens in the scene. Think of the prompt as a mini story that unfolds over the duration of the clip. For example, describe what the character is doing at the start, how the transition plays out, and where they end up. This kind of narrative prompt helps define a clear and coherent structure for the video.

WanVideo

In the final step, the video is sampled. Make sure to set the number of sampling steps to 30 in order to achieve a quality result.