+int swr_set_matrix(struct SwrContext *s, const double *matrix, int stride)
+{
+ int nb_in, nb_out, in, out;
+
+ if (!s || s->in_convert) // s needs to be allocated but not initialized
+ return AVERROR(EINVAL);
+ memset(s->matrix, 0, sizeof(s->matrix));
+ nb_in = av_get_channel_layout_nb_channels(s->in_ch_layout);
+ nb_out = av_get_channel_layout_nb_channels(s->out_ch_layout);
+ for (out = 0; out < nb_out; out++) {
+ for (in = 0; in < nb_in; in++)
+ s->matrix[out][in] = matrix[in];
+ matrix += stride;
+ }
+ s->rematrix_custom = 1;
+ return 0;
+}
+