qtdemux: Provide a 30 frames lead-in for MP3

mpegaudioparse suggests MP3 needs 10 or 30 frames of lead-in (depending on
mpegaudioversion, which we don't know here), thus provide at least 30 frames
lead-in for such cases as a followup to commit cbfa4531ee.
This commit is contained in:
Mart Raudsepp 2019-07-02 21:21:05 +03:00 committed by Olivier Crête
parent af618cb081
commit ade531183f

View file

@ -5141,8 +5141,20 @@ gst_qtdemux_activate_segment (GstQTDemux * qtdemux, QtDemuxStream * stream,
/* go back two frames to provide lead-in for non-raw audio decoders */
if (stream->subtype == FOURCC_soun && !stream->need_clip) {
guint32 lead_in = 2;
guint32 old_index = kf_index;
kf_index = MAX (kf_index, 2) - 2;
GstStructure *s = gst_caps_get_structure (CUR_STREAM (stream)->caps, 0);
if (gst_structure_has_name (s, "audio/mpeg")) {
gint mpegversion;
if (gst_structure_get_int (s, "mpegversion", &mpegversion)
&& mpegversion == 1) {
/* mp3 could need up to 30 frames of lead-in per mpegaudioparse */
lead_in = 30;
}
}
kf_index = MAX (kf_index, lead_in) - lead_in;
if (qtdemux_parse_samples (qtdemux, stream, kf_index)) {
GST_DEBUG_OBJECT (stream->pad,
"Moving backwards %u frames to ensure sufficient sound lead-in",