When mixing 3 front channels into 2, the center channel is mixed into left and right with the center mix level, not -3dB.
/* mix front center to front left/right */
if (unaccounted & AV_CH_FRONT_CENTER) {
if ((out_layout & AV_CH_LAYOUT_STEREO) == AV_CH_LAYOUT_STEREO) {
- matrix[FRONT_LEFT ][FRONT_CENTER] += M_SQRT1_2;
- matrix[FRONT_RIGHT][FRONT_CENTER] += M_SQRT1_2;
+ if ((in_layout & AV_CH_LAYOUT_STEREO) == AV_CH_LAYOUT_STEREO) {
+ matrix[FRONT_LEFT ][FRONT_CENTER] += center_mix_level;
+ matrix[FRONT_RIGHT][FRONT_CENTER] += center_mix_level;
+ } else {
+ matrix[FRONT_LEFT ][FRONT_CENTER] += M_SQRT1_2;
+ matrix[FRONT_RIGHT][FRONT_CENTER] += M_SQRT1_2;
+ }
} else
return AVERROR_PATCHWELCOME;
}