lavr: call mix_function_init() in ff_audio_mix_set_matrix()

This is needed if a custom matrix is set by the user after opening the
AVAudioResampleContext because the matrix channel count can change if
different mixing coefficients are used.

CC:libav-stable@libav.org
(cherry picked from commit f07ef2d9c9e9d1e84c532e9102594834e88a5c83)

Conflicts:

	libavresample/audio_mix.c

1 files changed, 1 insertions, 8 deletions

diff --git a/libavresample/audio_mix.c b/libavresample/audio_mix.c
index 2b3d9f1f7a..c0560288a5 100644
--- a/libavresample/audio_mix.c
+++ b/libavresample/audio_mix.c
@@ -401,10 +401,6 @@ AudioMix *ff_audio_mix_alloc(AVAudioResampleContext *avr)
         av_free(matrix_dbl);
     }
 
-    ret = mix_function_init(am);
-    if (ret < 0)
-        goto error;
-
     return am;
 
 error:
@@ -544,8 +540,5 @@ int ff_audio_mix_set_matrix(AudioMix *am, const double *matrix, int stride)
         return AVERROR(EINVAL);
     }
 
-    /* TODO: detect situations where we can just swap around pointers
-             instead of doing matrix multiplications with 0.0 and 1.0 */
-
-    return 0;
+    return mix_function_init(am);
 }