[FFmpeg-devel] [PATCH v3 2/3] avformat/mpegts: keep track of AVProgram.pmt_version and set AV_PROGRAM_CHANGED on version updates

[Aman Gupta]

From: Aman Gupta <aman at tmm1.net>

This can be used to detect changes to the streams in an AVProgram

Signed-off-by: Aman Gupta <aman at tmm1.net>
---
 libavformat/mpegts.c | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
index fc9bb3940e..e83238d733 100644
--- a/libavformat/mpegts.c
+++ b/libavformat/mpegts.c
@@ -330,12 +330,24 @@ static void set_pmt_found(MpegTSContext *ts, unsigned int programid)
     p->pmt_found = 1;
 }
 
-static void set_pcr_pid(AVFormatContext *s, unsigned int programid, unsigned int pid)
+static void update_av_program_info(AVFormatContext *s, unsigned int programid,
+                                   unsigned int pid, int version)
 {
     int i;
     for (i = 0; i < s->nb_programs; i++) {
-        if (s->programs[i]->id == programid) {
-            s->programs[i]->pcr_pid = pid;
+        AVProgram *program = s->programs[i];
+        if (program->id == programid) {
+            int old_pcr_pid = program->pcr_pid,
+                old_version = program->pmt_version;
+            program->pcr_pid = pid;
+            program->pmt_version = version;
+
+            if (old_version != -1 && old_version != version) {
+                program->flags |= AV_PROGRAM_CHANGED;
+                av_log(s, AV_LOG_DEBUG,
+                       "detected PMT change on program %d (version=%d/%d, pcr_pid=0x%x/0x%x)\n",
+                       programid, old_version, version, old_pcr_pid, pid);
+            }
             break;
         }
     }
@@ -2036,7 +2048,7 @@ static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len
         return;
     pcr_pid &= 0x1fff;
     add_pid_to_pmt(ts, h->id, pcr_pid);
-    set_pcr_pid(ts->stream, h->id, pcr_pid);
+    update_av_program_info(ts->stream, h->id, pcr_pid, h->version);
 
     av_log(ts->stream, AV_LOG_TRACE, "pcr_pid=0x%x\n", pcr_pid);
 
-- 
2.14.2