matroskademux: Parse successive Tracks elements
This patch allows matroskademux to parse a second Tracks element,
erroring out if the tracks are not compatible (different number, type or
codec) and emitting new caps and tag events should they have changed.
https://bugzilla.gnome.org/show_bug.cgi?id=793333
diff --git a/gst/matroska/matroska-demux.c b/gst/matroska/matroska-demux.c
index 7c8990c..08e5a60 100644
--- a/gst/matroska/matroska-demux.c
+++ b/gst/matroska/matroska-demux.c
@@ -2815,6 +2815,113 @@
return ret;
}
+static GstFlowReturn
+gst_matroska_demux_update_tracks (GstMatroskaDemux * demux, GstEbmlRead * ebml)
+{
+ GstFlowReturn ret = GST_FLOW_OK;
+ guint num_tracks_found = 0;
+ guint32 id;
+
+ GST_INFO_OBJECT (demux, "Reparsing Tracks element");
+
+ DEBUG_ELEMENT_START (demux, ebml, "Tracks");
+
+ if ((ret = gst_ebml_read_master (ebml, &id)) != GST_FLOW_OK) {
+ DEBUG_ELEMENT_STOP (demux, ebml, "Tracks", ret);
+ return ret;
+ }
+
+ while (ret == GST_FLOW_OK && gst_ebml_read_has_remaining (ebml, 1, TRUE)) {
+ if ((ret = gst_ebml_peek_id (ebml, &id)) != GST_FLOW_OK)
+ break;
+
+ switch (id) {
+ /* one track within the "all-tracks" header */
+ case GST_MATROSKA_ID_TRACKENTRY:{
+ GstMatroskaTrackContext *new_track;
+ gint old_track_index;
+ GstMatroskaTrackContext *old_track;
+ ret = gst_matroska_demux_parse_stream (demux, ebml, &new_track);
+ if (new_track == NULL)
+ break;
+ num_tracks_found++;
+
+ if (gst_matroska_read_common_tracknumber_unique (&demux->common,
+ new_track->num)) {
+ GST_ERROR_OBJECT (demux,
+ "Unexpected new TrackNumber: %" G_GUINT64_FORMAT, new_track->num);
+ goto track_mismatch_error;
+ }
+
+ old_track_index =
+ gst_matroska_read_common_stream_from_num (&demux->common,
+ new_track->num);
+ g_assert (old_track_index != -1);
+ old_track = g_ptr_array_index (demux->common.src, old_track_index);
+
+ if (old_track->type != new_track->type) {
+ GST_ERROR_OBJECT (demux,
+ "Mismatch reparsing track %" G_GUINT64_FORMAT
+ " on track type. Expected %d, found %d", new_track->num,
+ old_track->type, new_track->type);
+ goto track_mismatch_error;
+ }
+
+ if (g_strcmp0 (old_track->codec_id, new_track->codec_id) != 0) {
+ GST_ERROR_OBJECT (demux,
+ "Mismatch reparsing track %" G_GUINT64_FORMAT
+ " on codec id. Expected '%s', found '%s'", new_track->num,
+ old_track->codec_id, new_track->codec_id);
+ goto track_mismatch_error;
+ }
+
+ /* The new track matches the old track. No problems on our side.
+ * Let's make it replace the old track. */
+ new_track->pad = old_track->pad;
+ new_track->index = old_track->index;
+ new_track->pos = old_track->pos;
+ g_ptr_array_index (demux->common.src, old_track_index) = new_track;
+ gst_pad_set_element_private (new_track->pad, new_track);
+
+ if (!gst_caps_is_equal (old_track->caps, new_track->caps)) {
+ gst_pad_set_caps (new_track->pad, new_track->caps);
+ }
+
+ if (!gst_tag_list_is_equal (old_track->tags, new_track->tags)) {
+ GST_DEBUG_OBJECT (old_track->pad, "Sending tags %p: %"
+ GST_PTR_FORMAT, new_track->tags, new_track->tags);
+ gst_pad_push_event (new_track->pad,
+ gst_event_new_tag (gst_tag_list_copy (new_track->tags)));
+ }
+
+ gst_matroska_track_free (old_track);
+ break;
+
+ track_mismatch_error:
+ gst_matroska_track_free (new_track);
+ new_track = NULL;
+ ret = GST_FLOW_ERROR;
+ break;
+ }
+
+ default:
+ ret = gst_matroska_read_common_parse_skip (&demux->common, ebml,
+ "Track", id);
+ break;
+ }
+ }
+ DEBUG_ELEMENT_STOP (demux, ebml, "Tracks", ret);
+
+ if (ret != GST_FLOW_ERROR && demux->common.num_streams != num_tracks_found) {
+ GST_ERROR_OBJECT (demux,
+ "Mismatch on the number of tracks. Expected %du tracks, found %du",
+ demux->common.num_streams, num_tracks_found);
+ ret = GST_FLOW_ERROR;
+ }
+
+ return ret;
+}
+
/*
* Read signed/unsigned "EBML" numbers.
* Return: number of bytes processed.
@@ -4706,11 +4813,11 @@
}
break;
case GST_MATROSKA_ID_TRACKS:
+ GST_READ_CHECK (gst_matroska_demux_take (demux, read, &ebml));
if (!demux->tracks_parsed) {
- GST_READ_CHECK (gst_matroska_demux_take (demux, read, &ebml));
ret = gst_matroska_demux_parse_tracks (demux, &ebml);
} else {
- GST_READ_CHECK (gst_matroska_demux_flush (demux, read));
+ ret = gst_matroska_demux_update_tracks (demux, &ebml);
}
break;
case GST_MATROSKA_ID_CLUSTER:
