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StackHorizontal(clip1 clip, clip2 clip [, ...])
StackVertical(clip1 clip, clip2 clip [, ...])
StackHorizontal takes two or more video clips and displays them together in left-to-right order. The heights of the images and their color formats must be the same. Most other information (sound track, frame rate, etc) is taken from the first clip - see here for the resulting clip properties. StackVertical does the same, except from top to bottom.
Examples:
# compare frames with and without noise reduction:
StackVertical(last, last.SpatialSoften(2, 3, 6))
# show clips in variables a,b,c,d in a box like this:
# a b
# c d
StackVertical(StackHorizontal(a, b), StackHorizontal(c, d))
