From 82de8d71118f4eafd6a43e9ea9169bd411793798 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?John=20H=C3=B6gberg?= Date: Tue, 28 Apr 2015 10:20:33 +0200 Subject: [PATCH] mpegts: Update the PSI/SI table only if the version change If a PAT is finished while a PMT section filter is opened but not yet finished, the PMT section filter is closed and all the received data is discarded. This is usually not an issue but some multiplexers (With very quick PAT/PMT repetition settings) consistently emit a PMT section start, then a PAT, and then the rest of the PMT, causing the aforementioned behavior to result in no PMT being finished. In the most pathologic situation the stream information are lost and the probe fallback miscategorizes subtitles as mp3 audio. Avoid the issue through eliminating redundant PSI/SI table updates by checking their version field, which is required by the standard to be incremented on every change no matter how minor. CC: libav-stable@libav.org Signed-off-by: Luca Barbato --- libavformat/mpegts.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c index ae9d1f4e93..8f61f1727d 100644 --- a/libavformat/mpegts.c +++ b/libavformat/mpegts.c @@ -73,6 +73,7 @@ typedef void SetServiceCallback (void *opaque, int ret); typedef struct MpegTSSectionFilter { int section_index; int section_h_size; + int last_ver; uint8_t *section_buf; unsigned int check_crc : 1; unsigned int end_of_section_reached : 1; @@ -372,6 +373,8 @@ static MpegTSFilter *mpegts_open_section_filter(MpegTSContext *ts, sec->opaque = opaque; sec->section_buf = av_malloc(MAX_SECTION_SIZE); sec->check_crc = check_crc; + sec->last_ver = -1; + if (!sec->section_buf) { av_free(filter); return NULL; @@ -1255,6 +1258,7 @@ static void m4sl_cb(MpegTSFilter *filter, const uint8_t *section, int section_len) { MpegTSContext *ts = filter->u.section_filter.opaque; + MpegTSSectionFilter *tssf = &filter->u.section_filter; SectionHeader h; const uint8_t *p, *p_end; AVIOContext pb; @@ -1269,6 +1273,9 @@ static void m4sl_cb(MpegTSFilter *filter, const uint8_t *section, return; if (h.tid != M4OD_TID) return; + if (h.version == tssf->last_ver) + return; + tssf->last_ver = h.version; mp4_read_od(s, p, (unsigned) (p_end - p), mp4_descr, &mp4_descr_count, MAX_MP4_DESCR_COUNT); @@ -1507,6 +1514,7 @@ int ff_parse_mpeg2_descriptor(AVFormatContext *fc, AVStream *st, int stream_type static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len) { MpegTSContext *ts = filter->u.section_filter.opaque; + MpegTSSectionFilter *tssf = &filter->u.section_filter; SectionHeader h1, *h = &h1; PESContext *pes; AVStream *st; @@ -1526,6 +1534,9 @@ static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len p = section; if (parse_section_header(h, &p, p_end) < 0) return; + if (h->version == tssf->last_ver) + return; + tssf->last_ver = h->version; av_log(ts->stream, AV_LOG_TRACE, "sid=0x%x sec_num=%d/%d\n", h->id, h->sec_num, h->last_sec_num); @@ -1657,6 +1668,7 @@ out: static void pat_cb(MpegTSFilter *filter, const uint8_t *section, int section_len) { MpegTSContext *ts = filter->u.section_filter.opaque; + MpegTSSectionFilter *tssf = &filter->u.section_filter; SectionHeader h1, *h = &h1; const uint8_t *p, *p_end; int sid, pmt_pid; @@ -1670,6 +1682,9 @@ static void pat_cb(MpegTSFilter *filter, const uint8_t *section, int section_len return; if (h->tid != PAT_TID) return; + if (h->version == tssf->last_ver) + return; + tssf->last_ver = h->version; clear_programs(ts); for (;;) { @@ -1700,6 +1715,7 @@ static void pat_cb(MpegTSFilter *filter, const uint8_t *section, int section_len static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len) { MpegTSContext *ts = filter->u.section_filter.opaque; + MpegTSSectionFilter *tssf = &filter->u.section_filter; SectionHeader h1, *h = &h1; const uint8_t *p, *p_end, *desc_list_end, *desc_end; int onid, val, sid, desc_list_len, desc_tag, desc_len, service_type; @@ -1714,6 +1730,10 @@ static void sdt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len return; if (h->tid != SDT_TID) return; + if (h->version == tssf->last_ver) + return; + tssf->last_ver = h->version; + onid = get16(&p, p_end); if (onid < 0) return;