From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 94769420A1 for ; Mon, 27 Jun 2022 13:26:10 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 1542268B8C8; Mon, 27 Jun 2022 16:26:09 +0300 (EEST) Received: from mout-p-101.mailbox.org (mout-p-101.mailbox.org [80.241.56.151]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id E752868B656 for ; Mon, 27 Jun 2022 16:26:02 +0300 (EEST) Received: from smtp202.mailbox.org (smtp202.mailbox.org [10.196.197.202]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-101.mailbox.org (Postfix) with ESMTPS id 4LWpQJ4lx8z9sTR for ; Mon, 27 Jun 2022 15:26:00 +0200 (CEST) Message-ID: <9ec10c6b-e19a-47a5-c037-4c1a1255a9cd@gyani.pro> Date: Mon, 27 Jun 2022 18:55:48 +0530 MIME-Version: 1.0 Content-Language: en-US To: ffmpeg-devel@ffmpeg.org References: <20220625082951.11897-1-ffmpeg@gyani.pro> <20220625082951.11897-2-ffmpeg@gyani.pro> From: Gyan Doshi In-Reply-To: <20220625082951.11897-2-ffmpeg@gyani.pro> Subject: Re: [FFmpeg-devel] [PATCH v2 2/2] ffmpeg: add option -isync X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: Ping for the set. On 2022-06-25 01:59 pm, Gyan Doshi wrote: > This is a per-file input option that adjusts an input's timestamps > with reference to another input, so that emitted packet timestamps > account for the difference between the start times of the two inputs. > > Typical use case is to sync two or more live inputs such as from capture > devices. Both the target and reference input source timestamps should be > based on the same clock source. > > If not all inputs have timestamps, the wallclock times at the time of > reception of inputs shall be used. > --- > doc/ffmpeg.texi | 16 ++++++++++++ > fftools/ffmpeg.h | 2 ++ > fftools/ffmpeg_opt.c | 59 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 77 insertions(+) > > diff --git a/doc/ffmpeg.texi b/doc/ffmpeg.texi > index d943f4d6f5..8fc85d3a15 100644 > --- a/doc/ffmpeg.texi > +++ b/doc/ffmpeg.texi > @@ -518,6 +518,22 @@ see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1) > Like the @code{-ss} option but relative to the "end of file". That is negative > values are earlier in the file, 0 is at EOF. > > +@item -isync @var{input_index} (@emph{input}) > +Assign an input as a sync source. > + > +This will take the difference between the start times of the target and referenced inputs and > +offset the timestamps of the target file by that difference. The source timestamps of the two > +inputs should derive from the same clock source for expected results. If @code{copyts} is set > +then @code{start_at_zero} must also be set. If at least one of the inputs has no starting > +timestamp then the wallclock time at time of reception of the inputs is used as a best-effort > +sync basis. > + > +Acceptable values are those that refer to a valid ffmpeg input index. If the sync reference is > +the target index itself or @var{-1}, then no adjustment is made to target timestamps. A sync > +reference may not itself be synced to any other input. > + > +Default value is @var{-1}. > + > @item -itsoffset @var{offset} (@emph{input}) > Set the input time offset. > > diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h > index 69a368b8d1..dc74de6684 100644 > --- a/fftools/ffmpeg.h > +++ b/fftools/ffmpeg.h > @@ -118,6 +118,7 @@ typedef struct OptionsContext { > float readrate; > int accurate_seek; > int thread_queue_size; > + int input_sync_ref; > > SpecifierOpt *ts_scale; > int nb_ts_scale; > @@ -410,6 +411,7 @@ typedef struct InputFile { > at the moment when looping happens */ > AVRational time_base; /* time base of the duration */ > int64_t input_ts_offset; > + int input_sync_ref; > > int64_t ts_offset; > int64_t last_ts; > diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c > index e08455478f..de858efbe9 100644 > --- a/fftools/ffmpeg_opt.c > +++ b/fftools/ffmpeg_opt.c > @@ -235,6 +235,7 @@ static void init_options(OptionsContext *o) > o->chapters_input_file = INT_MAX; > o->accurate_seek = 1; > o->thread_queue_size = -1; > + o->input_sync_ref = -1; > } > > static int show_hwaccels(void *optctx, const char *opt, const char *arg) > @@ -287,6 +288,58 @@ static int parse_and_set_vsync(const char *arg, int *vsync_var, int file_idx, in > return 0; > } > > +static int apply_sync_offsets(void) > +{ > + for (int i = 0; i < nb_input_files; i++) { > + InputFile *ref, *self = input_files[i]; > + int64_t adjustment; > + int64_t self_start_time, ref_start_time, self_seek_start, ref_seek_start; > + int sync_fpw = 0; > + > + if (self->input_sync_ref == -1 || self->input_sync_ref == i) continue; > + if (self->input_sync_ref >= nb_input_files || self->input_sync_ref < -1) { > + av_log(NULL, AV_LOG_FATAL, "-isync for input %d references non-existent input %d.\n", i, self->input_sync_ref); > + exit_program(1); > + } > + > + if (copy_ts && !start_at_zero) { > + av_log(NULL, AV_LOG_FATAL, "Use of -isync requires that start_at_zero be set if copyts is set.\n"); > + exit_program(1); > + } > + > + ref = input_files[self->input_sync_ref]; > + if (ref->input_sync_ref != -1 && ref->input_sync_ref != self->input_sync_ref) { > + av_log(NULL, AV_LOG_ERROR, "-isync for input %d references a resynced input %d. Sync not set.\n", i, self->input_sync_ref); > + continue; > + } > + > + if (self->ctx->start_time_realtime != AV_NOPTS_VALUE && ref->ctx->start_time_realtime != AV_NOPTS_VALUE) { > + self_start_time = self->ctx->start_time_realtime; > + ref_start_time = ref->ctx->start_time_realtime; > + } else if (self->ctx->start_time != AV_NOPTS_VALUE && ref->ctx->start_time != AV_NOPTS_VALUE) { > + self_start_time = self->ctx->start_time; > + ref_start_time = ref->ctx->start_time; > + } else { > + self_start_time = self->ctx->first_pkt_wallclock; > + ref_start_time = ref->ctx->first_pkt_wallclock; > + sync_fpw = 1; > + } > + > + self_seek_start = self->start_time == AV_NOPTS_VALUE ? 0 : self->start_time; > + ref_seek_start = ref->start_time == AV_NOPTS_VALUE ? 0 : ref->start_time; > + > + adjustment = (self_start_time - ref_start_time) + !copy_ts*(self_seek_start - ref_seek_start) + ref->input_ts_offset; > + > + self->ts_offset += adjustment; > + > + av_log(NULL, AV_LOG_INFO, "Adjusted ts offset for Input #%d by %"PRId64"d us to sync with Input #%d", i, adjustment, self->input_sync_ref); > + if (sync_fpw) av_log(NULL, AV_LOG_INFO, " using reception wallclock time. Sync may not be obtained"); > + av_log(NULL, AV_LOG_INFO, ".\n"); > + } > + > + return 0; > +} > + > static int opt_filter_threads(void *optctx, const char *opt, const char *arg) > { > av_free(filter_nbthreads); > @@ -1305,6 +1358,7 @@ static int open_input_file(OptionsContext *o, const char *filename) > f->ist_index = nb_input_streams - ic->nb_streams; > f->start_time = o->start_time; > f->recording_time = o->recording_time; > + f->input_sync_ref = o->input_sync_ref; > f->input_ts_offset = o->input_ts_offset; > f->ts_offset = o->input_ts_offset - (copy_ts ? (start_at_zero && ic->start_time != AV_NOPTS_VALUE ? ic->start_time : 0) : timestamp); > f->nb_streams = ic->nb_streams; > @@ -3489,6 +3543,8 @@ int ffmpeg_parse_options(int argc, char **argv) > goto fail; > } > > + apply_sync_offsets(); > + > /* create the complex filtergraphs */ > ret = init_complex_filters(); > if (ret < 0) { > @@ -3603,6 +3659,9 @@ const OptionDef options[] = { > { "accurate_seek", OPT_BOOL | OPT_OFFSET | OPT_EXPERT | > OPT_INPUT, { .off = OFFSET(accurate_seek) }, > "enable/disable accurate seeking with -ss" }, > + { "isync", HAS_ARG | OPT_INT | OPT_OFFSET | > + OPT_EXPERT | OPT_INPUT, { .off = OFFSET(input_sync_ref) }, > + "Indicate the input index for sync reference", "sync ref" }, > { "itsoffset", HAS_ARG | OPT_TIME | OPT_OFFSET | > OPT_EXPERT | OPT_INPUT, { .off = OFFSET(input_ts_offset) }, > "set the input ts offset", "time_off" }, _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".