Character, indicating whether the left or right channel should be extracted,
or whether both channels should be averaged.
left
Object of class Wave containing monophonic sound,
to be used for the left channel.
right
Object of class Wave containing monophonic sound,
to be used for the right channel (if missing, the left channel is duplicated).
If right is missing,
Value
An object of class Wave.
If argument right is missing in stereo, a logical values is returned
that indicates whether left is stereo (TRUE) or mono (FALSE).