+static int select_reference_stream(AVFormatContext *s)
+{
+ SegmentContext *seg = s->priv_data;
+ int ret, i;
+
+ seg->reference_stream_index = -1;
+ if (!strcmp(seg->reference_stream_specifier, "auto")) {
+ /* select first index of type with highest priority */
+ int type_index_map[AVMEDIA_TYPE_NB];
+ static const enum AVMediaType type_priority_list[] = {
+ AVMEDIA_TYPE_VIDEO,
+ AVMEDIA_TYPE_AUDIO,
+ AVMEDIA_TYPE_SUBTITLE,
+ AVMEDIA_TYPE_DATA,
+ AVMEDIA_TYPE_ATTACHMENT
+ };
+ enum AVMediaType type;
+
+ for (i = 0; i < AVMEDIA_TYPE_NB; i++)
+ type_index_map[i] = -1;
+
+ /* select first index for each type */
+ for (i = 0; i < s->nb_streams; i++) {
+ type = s->streams[i]->codec->codec_type;
+ if ((unsigned)type < AVMEDIA_TYPE_NB && type_index_map[type] == -1
+ /* ignore attached pictures/cover art streams */
+ && !(s->streams[i]->disposition & AV_DISPOSITION_ATTACHED_PIC))
+ type_index_map[type] = i;
+ }
+
+ for (i = 0; i < FF_ARRAY_ELEMS(type_priority_list); i++) {
+ type = type_priority_list[i];
+ if ((seg->reference_stream_index = type_index_map[type]) >= 0)
+ break;
+ }
+ } else {
+ for (i = 0; i < s->nb_streams; i++) {
+ ret = avformat_match_stream_specifier(s, s->streams[i],
+ seg->reference_stream_specifier);
+ if (ret < 0)
+ return ret;
+ if (ret > 0) {
+ seg->reference_stream_index = i;
+ break;
+ }
+ }
+ }
+
+ if (seg->reference_stream_index < 0) {
+ av_log(s, AV_LOG_ERROR, "Could not select stream matching identifier '%s'\n",
+ seg->reference_stream_specifier);
+ return AVERROR(EINVAL);
+ }
+
+ return 0;
+}
+