std.SelectEvery(clip clip, int cycle, int[] offsets)

Returns a clip with only some of the frames in every cycle selected. The offsets given must be between 0 and cycle - 1.

Below are some examples of useful operations.

Return even numbered frames, starting with 0:

SelectEvery(clip=clip, cycle=2, offsets=0)

Return odd numbered frames, starting with 1:

SelectEvery(clip=clip, cycle=2, offsets=1)

Fixed pattern 1 in 5 decimation, first frame in every cycle removed:

SelectEvery(clip=clip, cycle=5, offsets=[1, 2, 3, 4])

Duplicate every fourth frame:

SelectEvery(clip=clip, cycle=4, offsets=[0, 1, 2, 3, 3])

In Python, std.SelectEvery can also be invoked by slicing a clip.

The clip’s frame rate is multiplied by the number of offsets and divided by cycle. The frame durations are multiplied by cycle and divided by the number of offsets.