swr: special case for empty channels in rematrix.

Speed += 10% overall for pan=stereo:FL=FL+FR from wav to null.
13 years ago · a8cdb7b95a
parent 1ea3b657d6
commit a8cdb7b95a
1 changed files with 3 additions and 0 deletions
--- a/libswresample/rematrix.c
+++ b/libswresample/rematrix.c
@ -280,6 +280,9 @@ int swri_rematrix(SwrContext *s, AudioData *out, AudioData *in, int len, int mus

    for(out_i=0; out_i<out->ch_count; out_i++){
        switch(s->matrix_ch[out_i][0]){
+        case 0:
+            memset(out->ch[out_i], 0, len * (s->int_sample_fmt == AV_SAMPLE_FMT_FLT ? sizeof(float) : sizeof(int16_t)));
+            break;
        case 1:
            in_i= s->matrix_ch[out_i][1];
            if(mustcopy || s->matrix[out_i][in_i]!=1.0){