- for-each-frame f vprocedure
- for-each-frame-but-last f vprocedure
- for-each-frame-reversed f vprocedure
- for-each-frame-indexed f vprocedure
- for-each-frame-indexed-but-last f vprocedure
- map-frame f vprocedure
- map-frame-but-last f vprocedure
- map-frame-indexed f vprocedure
- map-frame-indexed-but-last f vprocedure
Walk over the frames of a video. Note that this does not fetch any data, even though decoding must happen for frame-level accuracy, it simply calls the function with one argument, the frame index. The indexed versions of these functions also pass an index (guaranteed to be 0-based) into the current movie.