Select

"Select" redirects here. For the switch-like control function, see Internal Functions: Select

SelectEven/SelectOdd

SelectEven(clip clip)
SelectOdd(clip clip)

SelectEven makes an output video stream using only the even-numbered frames from the input. SelectOdd is its odd counterpart.

Since frames are numbered starting from zero, SelectEven actually selects the first, third, fifth,... frames by human counting conventions.

SelectEvery

SelectEvery(clip clip, int step-size, int offset1 [, int offset2, ...])

SelectEvery is a generalization of filters like SelectEven and Pulldown. The easiest way to describe it is by example:

SelectEvery(clip, 2, 0)         # identical to SelectEven(clip)
SelectEvery(clip, 2, 1)         # identical to SelectOdd(clip)
SelectEvery(clip, 10, 3, 6, 7)  # select frames 3, 6, 7, 13, 16, 17, 23, 26, 27, ... from source clip
SelectEvery(clip, 9, 0)         # select frames 0, 9, 18, 27, ... from source clip

And how about this:

# Take a 24fps progressive input clip and apply 3:2 pulldown,
# yielding a 30fps interlaced output clip
AssumeFrameBased()
SeparateFields()
SelectEvery(8, 0,1, 2,3,2, 5,4, 7,6,7)
Weave()

SelectRangeEvery

SelectRangeEvery(clip clip [, int every] [, int length] [, int offset] [, bool audio])

This filter is available starting from v2.5. The filter selects length number of frames every n frames, starting from frame offset. Default values are: Select 50 frames every 1500 frames, starting with first selection at frame 0. (every = 1500, length = 50, offset = 0).

Starting from v2.55, SelectRangeEvery will also process audio. To keep the original audio, use audio = false.

Examples:

# Selects the frames 0 to 13, 280 to 293, 560 to 573, etc.
SelectRangeEvery(clip, 280, 14)

# Selects the frames 2 to 15, 282 to 295, 562 to 575, etc.
SelectRangeEvery(clip, 280, 14, 2)

External Links

• Doom9 Forum - Deinterlacing BFF/TFF - which SelectEvery setting?