CHANNEL_NUMBER    703 modules/videoio/src/cap_libv4l.cpp        capture->inp.index = CHANNEL_NUMBER;
CHANNEL_NUMBER    920 modules/videoio/src/cap_libv4l.cpp        selectedChannel.channel=CHANNEL_NUMBER;
CHANNEL_NUMBER    851 modules/videoio/src/cap_v4l.cpp        capture->inp.index = CHANNEL_NUMBER;
CHANNEL_NUMBER   1039 modules/videoio/src/cap_v4l.cpp        selectedChannel.channel=CHANNEL_NUMBER;