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Trim(clip clip, int first_frame, int last_frame)
Trim(clip clip, int first_frame, int -num_frames)
Trim trims a video clip so that it includes only the frames first_frame through last_frame. The audio is similarly trimmed so that it stays synchronized. Remember AviSynth starts counting at frame 0.
If you pass a negative number for last_frames it returns frames first_frame through first_frame + num_frames - 1. For example:
Trim(100,-100) # same as Trim(100,199)
If you pass 0 for last_frame it means "end of the clip". This also means the only way to return just the first frame is to use the alternate syntax with num_frames. For example:
Trim(100,0) # deletes the first 100 frames
Trim(0,-1) # NOT the same as Trim(0,0) -- that would just return the whole thing
