Creating Sprite sheet without encoding the video

I am trying to create a sprite sheet without needing to encode the video. I would like to essentially have the video “passthrough” the encoding step, but still be used to create a Sprite.

Is this possible? It seems like the Sprite has to take in a Stream and Encoding and the Stream must be associated with a Muxing. Ideally, I’d like to just create a Sprite in isolation.