Message ID | 20171207093738.52358-2-rodger.combs@gmail.com |
---|---|
State | Superseded |
Headers | show |
On Thu, Dec 07, 2017 at 03:37:38AM -0600, Rodger Combs wrote: > --- > libavformat/avformat.h | 1 + > libavformat/internal.h | 5 +++++ > libavformat/options_table.h | 1 + > libavformat/utils.c | 12 ++++++++++++ > 4 files changed, 19 insertions(+) > > diff --git a/libavformat/avformat.h b/libavformat/avformat.h > index 4f2798a871..e2d88280a8 100644 > --- a/libavformat/avformat.h > +++ b/libavformat/avformat.h > @@ -1450,6 +1450,7 @@ typedef struct AVFormatContext { > #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats > #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops. > #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer > +#define AVFMT_FLAG_DISCARD_CORRUPT_TS 0x400000 ///< Discard timestamps of frames marked corrupt (replacing with wallclock offset from last non-corrupt frame) Using wallclock to fill in timestamps feels wrong if you discard a timestamp it should be set to AV_NOPTS_VALUE or recomputed based on information from the specification where this is possible, fps when constant or other hard information. [...]
On Thu, Dec 7, 2017 at 9:46 PM, Michael Niedermayer <michael@niedermayer.cc> wrote: > On Thu, Dec 07, 2017 at 03:37:38AM -0600, Rodger Combs wrote: >> --- >> libavformat/avformat.h | 1 + >> libavformat/internal.h | 5 +++++ >> libavformat/options_table.h | 1 + >> libavformat/utils.c | 12 ++++++++++++ >> 4 files changed, 19 insertions(+) >> >> diff --git a/libavformat/avformat.h b/libavformat/avformat.h >> index 4f2798a871..e2d88280a8 100644 >> --- a/libavformat/avformat.h >> +++ b/libavformat/avformat.h >> @@ -1450,6 +1450,7 @@ typedef struct AVFormatContext { >> #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats >> #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops. >> #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer >> +#define AVFMT_FLAG_DISCARD_CORRUPT_TS 0x400000 ///< Discard timestamps of frames marked corrupt (replacing with wallclock offset from last non-corrupt frame) > > Using wallclock to fill in timestamps feels wrong > if you discard a timestamp it should be set to AV_NOPTS_VALUE or > recomputed based on information from the specification where this is > possible, fps when constant or other hard information. > I agree, discard should be just that, set it to invalid. Wallclock is meaningless on anything but a live stream. - Hendrik
> On Dec 7, 2017, at 16:53, Hendrik Leppkes <h.leppkes@gmail.com> wrote: > > On Thu, Dec 7, 2017 at 9:46 PM, Michael Niedermayer > <michael@niedermayer.cc <mailto:michael@niedermayer.cc>> wrote: >> On Thu, Dec 07, 2017 at 03:37:38AM -0600, Rodger Combs wrote: >>> --- >>> libavformat/avformat.h | 1 + >>> libavformat/internal.h | 5 +++++ >>> libavformat/options_table.h | 1 + >>> libavformat/utils.c | 12 ++++++++++++ >>> 4 files changed, 19 insertions(+) >>> >>> diff --git a/libavformat/avformat.h b/libavformat/avformat.h >>> index 4f2798a871..e2d88280a8 100644 >>> --- a/libavformat/avformat.h >>> +++ b/libavformat/avformat.h >>> @@ -1450,6 +1450,7 @@ typedef struct AVFormatContext { >>> #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats >>> #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops. >>> #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer >>> +#define AVFMT_FLAG_DISCARD_CORRUPT_TS 0x400000 ///< Discard timestamps of frames marked corrupt (replacing with wallclock offset from last non-corrupt frame) >> >> Using wallclock to fill in timestamps feels wrong >> if you discard a timestamp it should be set to AV_NOPTS_VALUE or >> recomputed based on information from the specification where this is >> possible, fps when constant or other hard information. >> > > I agree, discard should be just that, set it to invalid. Wallclock is > meaningless on anything but a live stream. My intended use-case is live streams, where wallclock can be more useful than deriving from fps if e.g. entire packets are dropped. I could have one flag to unset timestamps on corrupt packets, and another to fill unset DTS from wallclock? > > - Hendrik > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org <mailto:ffmpeg-devel@ffmpeg.org> > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel <http://ffmpeg.org/mailman/listinfo/ffmpeg-devel>
diff --git a/libavformat/avformat.h b/libavformat/avformat.h index 4f2798a871..e2d88280a8 100644 --- a/libavformat/avformat.h +++ b/libavformat/avformat.h @@ -1450,6 +1450,7 @@ typedef struct AVFormatContext { #define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats #define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops. #define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer +#define AVFMT_FLAG_DISCARD_CORRUPT_TS 0x400000 ///< Discard timestamps of frames marked corrupt (replacing with wallclock offset from last non-corrupt frame) /** * Maximum size of the data read from input for determining diff --git a/libavformat/internal.h b/libavformat/internal.h index 36a57214ce..39a69cf630 100644 --- a/libavformat/internal.h +++ b/libavformat/internal.h @@ -192,6 +192,11 @@ struct AVStreamInternal { int need_context_update; FFFrac *priv_pts; + + /** + * The wallclock timestamp of the most recent read packet (if AVFMT_FLAG_DISCARD_CORRUPT_TS is set) + */ + int64_t cur_wallclock_time; }; #ifdef __GNUC__ diff --git a/libavformat/options_table.h b/libavformat/options_table.h index b8fa47c6fd..515574d3e0 100644 --- a/libavformat/options_table.h +++ b/libavformat/options_table.h @@ -58,6 +58,7 @@ static const AVOption avformat_options[] = { {"bitexact", "do not write random/volatile data", 0, AV_OPT_TYPE_CONST, { .i64 = AVFMT_FLAG_BITEXACT }, 0, 0, E, "fflags" }, {"shortest", "stop muxing with the shortest stream", 0, AV_OPT_TYPE_CONST, { .i64 = AVFMT_FLAG_SHORTEST }, 0, 0, E, "fflags" }, {"autobsf", "add needed bsfs automatically", 0, AV_OPT_TYPE_CONST, { .i64 = AVFMT_FLAG_AUTO_BSF }, 0, 0, E, "fflags" }, +{"discardcorruptts", "discard timestamps on corrupted frames", 0, AV_OPT_TYPE_CONST, { .i64 = AVFMT_FLAG_DISCARD_CORRUPT_TS }, 0, 0, E, "fflags" }, {"analyzeduration", "specify how many microseconds are analyzed to probe the input", OFFSET(max_analyze_duration), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT64_MAX, D}, {"cryptokey", "decryption key", OFFSET(key), AV_OPT_TYPE_BINARY, {.dbl = 0}, 0, 0, D}, {"indexmem", "max memory used for timestamp index (per stream)", OFFSET(max_index_size), AV_OPT_TYPE_INT, {.i64 = 1<<20 }, 0, INT_MAX, D}, diff --git a/libavformat/utils.c b/libavformat/utils.c index 84e49208b8..1adb007244 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -873,6 +873,18 @@ int ff_read_packet(AVFormatContext *s, AVPacket *pkt) st->cur_dts = wrap_timestamp(st, st->cur_dts); } + if ((s->flags & AVFMT_FLAG_DISCARD_CORRUPT_TS)) { + int64_t cur_wallclock_time = av_gettime_relative(); + if (pkt->flags & AV_PKT_FLAG_CORRUPT) { + int64_t wallclock_offset = av_rescale_q(st->internal->cur_wallclock_time - cur_wallclock_time, AV_TIME_BASE_Q, st->time_base); + pkt->pts = pkt->dts = st->cur_dts + FFMAX(wallclock_offset, 1); + av_log(s, AV_LOG_WARNING, + "Discarded timestamp on corrupted packet (stream = %d)\n", + pkt->stream_index); + } + st->internal->cur_wallclock_time = cur_wallclock_time; + } + pkt->dts = wrap_timestamp(st, pkt->dts); pkt->pts = wrap_timestamp(st, pkt->pts);