[FFmpeg-devel] [PATCH] avformat: set start_time_realtime when demuxing

[Gyan Doshi]

Add new flag AVFMT_START_REALTIME for the couple of demuxers that set it
internally.
---
 doc/APIchanges         | 3 +++
 libavformat/avformat.h | 1 +
 libavformat/demux.c    | 3 +++
 libavformat/rtsp.c     | 3 ++-
 libavformat/version.h  | 2 +-
 5 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/doc/APIchanges b/doc/APIchanges
index 5857e67ae6..4aa9e36777 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -14,6 +14,9 @@ libavutil:     2021-04-27
 
 API changes, most recent first:
 
+2022-06-xx - xxxxxxxxxx - lavf 59.26.100 - avformat.h
+  Add AVFMT_START_REALTIME flag.
+
 2022-06-12 - xxxxxxxxxx - lavf 59.25.100 - avio.h
   Add avio_vprintf(), similar to avio_printf() but allow to use it
   from within a function taking a variable argument list as input.
diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index f12fa7d904..4e247d68fc 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -499,6 +499,7 @@ typedef struct AVProbeData {
                                         The user or muxer can override this through
                                         AVFormatContext.avoid_negative_ts
                                         */
+#define AVFMT_START_REALTIME 0x80000 /**< Demuxer sets start_time_realtime */
 
 #define AVFMT_SEEK_TO_PTS   0x4000000 /**< Seeking is based on PTS */
 
diff --git a/libavformat/demux.c b/libavformat/demux.c
index 1620716716..28c6966e71 100644
--- a/libavformat/demux.c
+++ b/libavformat/demux.c
@@ -628,6 +628,9 @@ FF_ENABLE_DEPRECATION_WARNINGS
 
         force_codec_ids(s, st);
 
+        if (!(s->iformat->flags & AVFMT_START_REALTIME) && s->start_time_realtime == AV_NOPTS_VALUE)
+            s->start_time_realtime = av_gettime();
+
         /* TODO: audio: time filter; video: frame reordering (pts != dts) */
         if (s->use_wallclock_as_timestamps)
             pkt->dts = pkt->pts = av_rescale_q(av_gettime(), AV_TIME_BASE_Q, st->time_base);
diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
index 88e9ef5226..2cafe33887 100644
--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -2489,6 +2489,7 @@ const AVInputFormat ff_sdp_demuxer = {
     .read_header    = sdp_read_header,
     .read_packet    = ff_rtsp_fetch_packet,
     .read_close     = sdp_read_close,
+    .flags          = AVFMT_START_REALTIME,
     .priv_class     = &sdp_demuxer_class,
 };
 #endif /* CONFIG_SDP_DEMUXER */
@@ -2648,7 +2649,7 @@ const AVInputFormat ff_rtp_demuxer = {
     .read_header    = rtp_read_header,
     .read_packet    = ff_rtsp_fetch_packet,
     .read_close     = sdp_read_close,
-    .flags          = AVFMT_NOFILE,
+    .flags          = AVFMT_NOFILE | AVFMT_START_REALTIME,
     .priv_class     = &rtp_demuxer_class,
 };
 #endif /* CONFIG_RTP_DEMUXER */
diff --git a/libavformat/version.h b/libavformat/version.h
index 966ebb7ed3..0708d619c0 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -31,7 +31,7 @@
 
 #include "version_major.h"
 
-#define LIBAVFORMAT_VERSION_MINOR  25
+#define LIBAVFORMAT_VERSION_MINOR  26
 #define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
-- 
2.36.1