From 8bf732cda69bb93be200f8f7e56ee97dd44ad334 Mon Sep 17 00:00:00 2001 From: Marton Balint Date: Mon, 12 Aug 2019 23:32:11 +0200 Subject: [PATCH] avformat/mpegtsenc: add support for setting PCR interval for VBR streams Also document the algorithm for the default PCR interval. Fixes ticket #8061. Signed-off-by: Marton Balint --- doc/muxers.texi | 6 ++++-- libavformat/mpegtsenc.c | 9 +++++---- 2 files changed, 9 insertions(+), 6 deletions(-) diff --git a/doc/muxers.texi b/doc/muxers.texi index 019eee61459..c27bfee4f5b 100644 --- a/doc/muxers.texi +++ b/doc/muxers.texi @@ -1619,8 +1619,10 @@ is @code{-1}, which results in shifting timestamps so that they start from 0. Omit the PES packet length for video packets. Default is @code{1} (true). @item pcr_period @var{integer} -Override the default PCR retransmission time in milliseconds. Ignored if -variable muxrate is selected. Default is @code{20}. +Override the default PCR retransmission time in milliseconds. Default is +@code{-1} which means that the PCR interval will be determined automatically: +20 ms is used for CBR streams, the highest multiple of the frame duration which +is less than 100 ms is used for VBR streams. @item pat_period @var{double} Maximum time in seconds between PAT/PMT tables. diff --git a/libavformat/mpegtsenc.c b/libavformat/mpegtsenc.c index 5cdd9d33132..4ff8725c7cd 100644 --- a/libavformat/mpegtsenc.c +++ b/libavformat/mpegtsenc.c @@ -790,10 +790,11 @@ static void enable_pcr_generation_for_stream(AVFormatContext *s, AVStream *pcr_s MpegTSWrite *ts = s->priv_data; MpegTSWriteStream *ts_st = pcr_st->priv_data; - if (ts->mux_rate > 1) { - ts_st->pcr_period = av_rescale(ts->pcr_period_ms, PCR_TIME_BASE, 1000); + if (ts->mux_rate > 1 || ts->pcr_period_ms >= 0) { + int pcr_period_ms = ts->pcr_period_ms == -1 ? PCR_RETRANS_TIME : ts->pcr_period_ms; + ts_st->pcr_period = av_rescale(pcr_period_ms, PCR_TIME_BASE, 1000); } else { - /* For VBR we select the highest multiple of frame duration which is less than 100 ms. */ + /* By default, for VBR we select the highest multiple of frame duration which is less than 100 ms. */ int64_t frame_period = 0; if (pcr_st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) { int frame_size = av_get_audio_frame_duration2(pcr_st->codecpar, 0); @@ -1964,7 +1965,7 @@ static const AVOption options[] = { { .i64 = 1 }, 0, 1, AV_OPT_FLAG_ENCODING_PARAM }, { "pcr_period", "PCR retransmission time in milliseconds", offsetof(MpegTSWrite, pcr_period_ms), AV_OPT_TYPE_INT, - { .i64 = PCR_RETRANS_TIME }, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM }, + { .i64 = -1 }, -1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM }, { "pat_period", "PAT/PMT retransmission time limit in seconds", offsetof(MpegTSWrite, pat_period), AV_OPT_TYPE_DOUBLE, { .dbl = INT_MAX }, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM }, -- 2.39.2