From 157542ebc15dd175e5b4d14ffa92afd74ab4a991 Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Sun, 27 Jan 2013 14:47:54 -0500 Subject: lavr: fix mixing matrix reduction when normalization is disabled In some cases when an input contributes fully to the corresponding output, other inputs may also contribute to the same output. This is the case, for example, for the default 5.1 to stereo downmix matrix without normalization. --- libavresample/audio_mix.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'libavresample/audio_mix.c') diff --git a/libavresample/audio_mix.c b/libavresample/audio_mix.c index 487bddf746..b69bfbcf3e 100644 --- a/libavresample/audio_mix.c +++ b/libavresample/audio_mix.c @@ -572,11 +572,22 @@ static void reduce_matrix(AudioMix *am, const double *matrix, int stride) int skip = 1; for (o = 0; o < am->out_channels; o++) { + int i0; if ((o != i && matrix[o * stride + i] != 0.0) || (o == i && matrix[o * stride + i] != 1.0)) { skip = 0; break; } + /* if the input contributes fully to the output, also check that no + other inputs contribute to this output */ + if (o == i) { + for (i0 = 0; i0 < am->in_channels; i0++) { + if (i0 != i && matrix[o * stride + i0] != 0.0) { + skip = 0; + break; + } + } + } } if (skip) { am->input_skip[i] = 1; -- cgit v1.2.3