Optional. Transform the metadata on the input buffer to the
output buffer. By default this method is copies all meta without
tags and meta with only the "video" tag. subclasses can
implement this method and return true if the metadata is to be
copied. Since: 1.6
Optional. Transform the metadata on the input buffer to the output buffer. By default this method is copies all meta without tags and meta with only the "video" tag. subclasses can implement this method and return true if the metadata is to be copied. Since: 1.6