# ShuffleChannels

std.ShuffleChannels(anode[] clips, int[] channels_in, int[] channels_out)

  ShuffleChannels can extract and combine channels from different clips in the most general way possible.

  Most of the returned clip’s properties are implicitly determined from the first clip given to clips.

  The clips parameter takes one or more clips with the same format. If the clips are different lengths they’ll be zero extended to that of the longest.

  The argument channels_in controls which of the input clips’ channels to use and takes a channel constants as its argument. Specifying a non-existent channel is an error. If more channels_in than clips values are specified then the last clip in the clips list is reused as a source. In addition to the channel constant it’s also possible to specify the nth channel by using negative numbers.

  The output channel mapping is determined by channels_out and corresponds to the input channel order. The number of channels_out entries must be the same as the number of channels_in entries. Specifying the same output channel twice is an error.

  Below are some examples of useful operations.

  Extract the left channel (assuming it exists):

      ShuffleChannels(clips=clip, channels_in=vs.FRONT_LEFT, channels_out=vs.FRONT_LEFT)

  Swap left and right audio channels in a stereo clip:

      ShuffleChannels(clips=clip, channels_in=[vs.FRONT_RIGHT, vs.FRONT_LEFT], channels_out=[vs.FRONT_LEFT, vs.FRONT_RIGHT])

  Swap left and right audio channels in a stereo clip (alternate ordering of arguments):

      ShuffleChannels(clips=clip, channels_in=[vs.FRONT_LEFT, vs.FRONT_RIGHT], channels_out=[vs.FRONT_RIGHT, vs.FRONT_LEFT])

  Swap left and right audio channels in a stereo clip (alternate indexing):

      ShuffleChannels(clips=clip, channels_in=[-2, -1], channels_out=[vs.FRONT_LEFT, vs.FRONT_RIGHT])

  Merge 2 mono audio clips into a single stereo clip:

      ShuffleChannels(clips=[clipa, clipb], channels_in=[vs.FRONT_LEFT, vs.FRONT_LEFT], channels_out=[vs.FRONT_LEFT, vs.FRONT_RIGHT])