mpegtsdemux: Protect bitrate estimation against bogus values.

If the estimated bitrate is lower than 188 bytes, there's most likely
something completely wrong with the two samples. If that happens,
force recalculation.

Use guint64 for observation PCR, I saw cases where it would overflow.
This commit is contained in:
Edward Hervey 2009-05-11 16:59:20 +02:00
parent bc062b9acf
commit f9dfc44a67
2 changed files with 18 additions and 5 deletions

View file

@ -2355,14 +2355,27 @@ gst_mpegts_demux_parse_transport_packet (GstMpegTSDemux * demux,
MPEGTS_NORMAL_TS_PACKETSIZE - 1);
if (demux->pcr[1] != -1 && demux->bitrate == -1) {
GST_DEBUG_OBJECT (demux, "stream->last_PCR_difference: %" G_GINT64_FORMAT
guint64 bitrate;
GST_DEBUG_OBJECT (demux, "pcr[0]:%" G_GUINT64_FORMAT, demux->pcr[0]);
GST_DEBUG_OBJECT (demux, "pcr[1]:%" G_GUINT64_FORMAT, demux->pcr[1]);
GST_DEBUG_OBJECT (demux, "diff in time %" GST_TIME_FORMAT,
GST_TIME_ARGS (MPEGTIME_TO_GSTTIME (demux->pcr[1] - demux->pcr[0])));
GST_DEBUG_OBJECT (demux, "stream->last_PCR_difference: %" G_GUINT64_FORMAT
", demux->num_packets %" G_GUINT64_FORMAT,
demux->pcr[1] - demux->pcr[0], demux->num_packets);
demux->bitrate = gst_util_uint64_scale (GST_SECOND,
bitrate = gst_util_uint64_scale (GST_SECOND,
MPEGTS_NORMAL_TS_PACKETSIZE * demux->num_packets,
MPEGTIME_TO_GSTTIME (demux->pcr[1] - demux->pcr[0]));
GST_DEBUG_OBJECT (demux, "bitrate is %" G_GINT64_FORMAT
" bytes per second", demux->bitrate);
/* somehow... I doubt a bitrate below one packet per second is valid */
if (bitrate > MPEGTS_NORMAL_TS_PACKETSIZE - 1) {
demux->bitrate = bitrate;
GST_DEBUG_OBJECT (demux, "bitrate is %" G_GINT64_FORMAT
" bytes per second", demux->bitrate);
} else {
GST_WARNING_OBJECT (demux, "Couldn't compute valid bitrate, recomputing");
demux->pcr[0] = demux->pcr[1] = -1;
demux->num_packets = -1;
}
}
demux->num_packets++;
return ret;

View file

@ -213,7 +213,7 @@ struct _GstMpegTSDemux {
gint64 bitrate;
/* Two PCRs observations to calculate bitrate */
gint64 pcr[2];
guint64 pcr[2];
/* Cached duration estimation */
GstClockTime cache_duration;