CH_LAYOUT_STEREO_DOWNMIX  114 libavcodec/audioconvert.c     { "5.1+downmix", 8,  CH_LAYOUT_5POINT1|CH_LAYOUT_STEREO_DOWNMIX, },
CH_LAYOUT_STEREO_DOWNMIX  117 libavcodec/audioconvert.c     { "7.1+downmix", 10, CH_LAYOUT_7POINT1|CH_LAYOUT_STEREO_DOWNMIX, },