video-color: allow to define colorimetry quatruplet using strings
At the moment colorimetry can either be defined using a well known name (
colorimetry=bt601) or by defining a numerical quatruplet with the range, matrix, transfer and primaries values (
colorimetry=2:4:5:4), see https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/blob/master/gst-libs/gst/video/video-color.c#L115
The latter isn't very user friendly and hard to read in logs as the numerical values of the enums are being used directly.
I was wondering if it would makes sense to add support for a string representation of this quatruplet so we could have something like