[FFmpeg-devel] [PATCH 1/6] avformat/mpegtsenc: fix incorrect PCR selection with multiple programs
Marton Balint
cus at passwd.hu
Fri Aug 9 00:27:48 EEST 2019
The MPEG-TS muxer had a serious bug related to the use of multiple programs:
in that case, the PCR pid selection was incomplete for all services except one.
This patch solves this problem and selects a stream to become PCR for each
service, preferably the video stream.
This patch also moves pcr calculation attributes to MpegTSWriteStream from
MpegTSService. PCR is a per-stream and not per-service thing, so it was
misleading to refer to it as something that is per-service.
Also remove *service from MpegTSWriteStream because a stream can belong to
multiple services so it was misleading to select one for each stream.
You can check the result with this example command:
./ffmpeg -loglevel verbose -y -f lavfi -i \
"testsrc=s=64x64:d=10,split=2[out0][tmp1];[tmp1]vflip[out1];sine=d=10,asetnsamples=1152[out2]" \
-flags +bitexact -fflags +bitexact -sws_flags +accurate_rnd+bitexact \
-codec:v libx264 -codec:a mp2 -pix_fmt yuv420p \
-map '0:v:0' \
-map '0:v:1' \
-map '0:a:0' \
-program st=0:st=2 -program st=1:st=2 -program st=2 -program st=0 -f mpegts out.ts
You should now see this:
[mpegts @ 0x37505c0] service 1 using PCR in pid=256
[mpegts @ 0x37505c0] service 2 using PCR in pid=257
[mpegts @ 0x37505c0] service 3 using PCR in pid=258
[mpegts @ 0x37505c0] service 4 using PCR in pid=256
Fixes ticket #8039.
v2: a video is stream is preferred if there are no programs, just like before
the patch.
Signed-off-by: Marton Balint <cus at passwd.hu>
---
libavformat/mpegtsenc.c | 144 +++++++++++++++++++++++++++---------------------
1 file changed, 80 insertions(+), 64 deletions(-)
diff --git a/libavformat/mpegtsenc.c b/libavformat/mpegtsenc.c
index fc0ea225c6..661aa4066d 100644
--- a/libavformat/mpegtsenc.c
+++ b/libavformat/mpegtsenc.c
@@ -57,8 +57,6 @@ typedef struct MpegTSService {
uint8_t name[256];
uint8_t provider_name[256];
int pcr_pid;
- int pcr_packet_count;
- int pcr_packet_period;
AVProgram *program;
} MpegTSService;
@@ -228,7 +226,6 @@ static int mpegts_write_section1(MpegTSSection *s, int tid, int id,
#define PCR_RETRANS_TIME 20
typedef struct MpegTSWriteStream {
- struct MpegTSService *service;
int pid; /* stream associated pid */
int cc;
int discontinuity;
@@ -242,6 +239,9 @@ typedef struct MpegTSWriteStream {
AVFormatContext *amux;
AVRational user_tb;
+ int pcr_packet_count;
+ int pcr_packet_period;
+
/* For Opus */
int opus_queued_samples;
int opus_pending_trim_start;
@@ -769,12 +769,73 @@ static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
avio_write(ctx->pb, packet, TS_PACKET_SIZE);
}
+static void enable_pcr_generation_for_stream(AVFormatContext *s, AVStream *pcr_st)
+{
+ MpegTSWrite *ts = s->priv_data;
+ MpegTSWriteStream *ts_st = pcr_st->priv_data;
+
+ if (ts->mux_rate > 1) {
+ ts_st->pcr_packet_period = (int64_t)ts->mux_rate * ts->pcr_period /
+ (TS_PACKET_SIZE * 8 * 1000);
+ } else {
+ if (pcr_st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
+ int frame_size = av_get_audio_frame_duration2(pcr_st->codecpar, 0);
+ if (!frame_size) {
+ av_log(s, AV_LOG_WARNING, "frame size not set\n");
+ ts_st->pcr_packet_period =
+ pcr_st->codecpar->sample_rate / (10 * 512);
+ } else {
+ ts_st->pcr_packet_period =
+ pcr_st->codecpar->sample_rate / (10 * frame_size);
+ }
+ } else {
+ // max delta PCR 0.1s
+ // TODO: should be avg_frame_rate
+ ts_st->pcr_packet_period =
+ ts_st->user_tb.den / (10 * ts_st->user_tb.num);
+ }
+ if (!ts_st->pcr_packet_period)
+ ts_st->pcr_packet_period = 1;
+ }
+
+ // output a PCR as soon as possible
+ ts_st->pcr_packet_count = ts_st->pcr_packet_period;
+}
+
+static void select_pcr_streams(AVFormatContext *s)
+{
+ MpegTSWrite *ts = s->priv_data;
+
+ for (int i = 0; i < ts->nb_services; i++) {
+ MpegTSService *service = ts->services[i];
+ AVStream *pcr_st = NULL;
+ AVProgram *program = service->program;
+ int nb_streams = program ? program->nb_stream_indexes : s->nb_streams;
+
+ for (int j = 0; j < nb_streams; j++) {
+ AVStream *st = s->streams[program ? program->stream_index[j] : j];
+ if (!pcr_st ||
+ pcr_st->codecpar->codec_type != AVMEDIA_TYPE_VIDEO && st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
+ {
+ pcr_st = st;
+ }
+ }
+
+ if (pcr_st) {
+ MpegTSWriteStream *ts_st = pcr_st->priv_data;
+ service->pcr_pid = ts_st->pid;
+ enable_pcr_generation_for_stream(s, pcr_st);
+ av_log(s, AV_LOG_VERBOSE, "service %i using PCR in pid=%i\n", service->sid, service->pcr_pid);
+ }
+ }
+}
+
static int mpegts_init(AVFormatContext *s)
{
MpegTSWrite *ts = s->priv_data;
MpegTSWriteStream *ts_st;
MpegTSService *service;
- AVStream *st, *pcr_st = NULL;
+ AVStream *st;
AVDictionaryEntry *title, *provider;
int i, j;
const char *service_name;
@@ -853,7 +914,6 @@ static int mpegts_init(AVFormatContext *s)
/* assign pids to each stream */
for (i = 0; i < s->nb_streams; i++) {
- AVProgram *program;
st = s->streams[i];
ts_st = av_mallocz(sizeof(MpegTSWriteStream));
@@ -872,17 +932,6 @@ static int mpegts_init(AVFormatContext *s)
goto fail;
}
- program = av_find_program_from_stream(s, NULL, i);
- if (program) {
- for (j = 0; j < ts->nb_services; j++) {
- if (ts->services[j]->program == program) {
- service = ts->services[j];
- break;
- }
- }
- }
-
- ts_st->service = service;
/* MPEG pid values < 16 are reserved. Applications which set st->id in
* this range are assigned a calculated pid. */
if (st->id < 16) {
@@ -895,10 +944,12 @@ static int mpegts_init(AVFormatContext *s)
ret = AVERROR(EINVAL);
goto fail;
}
- if (ts_st->pid == service->pmt.pid) {
- av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
- ret = AVERROR(EINVAL);
- goto fail;
+ for (j = 0; j < ts->nb_services; j++) {
+ if (ts_st->pid == ts->services[j]->pmt.pid) {
+ av_log(s, AV_LOG_ERROR, "Duplicate stream id %d\n", ts_st->pid);
+ ret = AVERROR(EINVAL);
+ goto fail;
+ }
}
for (j = 0; j < i; j++) {
if (pids[j] == ts_st->pid) {
@@ -913,12 +964,6 @@ static int mpegts_init(AVFormatContext *s)
ts_st->first_pts_check = 1;
ts_st->cc = 15;
ts_st->discontinuity = ts->flags & MPEGTS_FLAG_DISCONT;
- /* update PCR pid by using the first video stream */
- if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
- service->pcr_pid == 0x1fff) {
- service->pcr_pid = ts_st->pid;
- pcr_st = st;
- }
if (st->codecpar->codec_id == AV_CODEC_ID_AAC &&
st->codecpar->extradata_size > 0) {
AVStream *ast;
@@ -953,17 +998,7 @@ static int mpegts_init(AVFormatContext *s)
av_freep(&pids);
- /* if no video stream, use the first stream as PCR */
- if (service->pcr_pid == 0x1fff && s->nb_streams > 0) {
- pcr_st = s->streams[0];
- ts_st = pcr_st->priv_data;
- service->pcr_pid = ts_st->pid;
- } else
- ts_st = pcr_st->priv_data;
-
if (ts->mux_rate > 1) {
- service->pcr_packet_period = (int64_t)ts->mux_rate * ts->pcr_period /
- (TS_PACKET_SIZE * 8 * 1000);
ts->sdt_packet_period = (int64_t)ts->mux_rate * SDT_RETRANS_TIME /
(TS_PACKET_SIZE * 8 * 1000);
ts->pat_packet_period = (int64_t)ts->mux_rate * PAT_RETRANS_TIME /
@@ -975,26 +1010,10 @@ static int mpegts_init(AVFormatContext *s)
/* Arbitrary values, PAT/PMT will also be written on video key frames */
ts->sdt_packet_period = 200;
ts->pat_packet_period = 40;
- if (pcr_st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
- int frame_size = av_get_audio_frame_duration2(pcr_st->codecpar, 0);
- if (!frame_size) {
- av_log(s, AV_LOG_WARNING, "frame size not set\n");
- service->pcr_packet_period =
- pcr_st->codecpar->sample_rate / (10 * 512);
- } else {
- service->pcr_packet_period =
- pcr_st->codecpar->sample_rate / (10 * frame_size);
- }
- } else {
- // max delta PCR 0.1s
- // TODO: should be avg_frame_rate
- service->pcr_packet_period =
- ts_st->user_tb.den / (10 * ts_st->user_tb.num);
- }
- if (!service->pcr_packet_period)
- service->pcr_packet_period = 1;
}
+ select_pcr_streams(s);
+
ts->last_pat_ts = AV_NOPTS_VALUE;
ts->last_sdt_ts = AV_NOPTS_VALUE;
// The user specified a period, use only it
@@ -1005,8 +1024,6 @@ static int mpegts_init(AVFormatContext *s)
ts->sdt_packet_period = INT_MAX;
}
- // output a PCR as soon as possible
- service->pcr_packet_count = service->pcr_packet_period;
ts->pat_packet_count = ts->pat_packet_period - 1;
ts->sdt_packet_count = ts->sdt_packet_period - 1;
@@ -1015,8 +1032,7 @@ static int mpegts_init(AVFormatContext *s)
else
av_log(s, AV_LOG_VERBOSE, "muxrate %d, ", ts->mux_rate);
av_log(s, AV_LOG_VERBOSE,
- "pcr every %d pkts, sdt every %d, pat/pmt every %d pkts\n",
- service->pcr_packet_period,
+ "sdt every %d, pat/pmt every %d pkts\n",
ts->sdt_packet_period, ts->pat_packet_period);
if (ts->m2ts_mode == -1) {
@@ -1198,12 +1214,12 @@ static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
force_pat = 0;
write_pcr = 0;
- if (ts_st->pid == ts_st->service->pcr_pid) {
+ if (ts_st->pcr_packet_period) {
if (ts->mux_rate > 1 || is_start) // VBR pcr period is based on frames
- ts_st->service->pcr_packet_count++;
- if (ts_st->service->pcr_packet_count >=
- ts_st->service->pcr_packet_period) {
- ts_st->service->pcr_packet_count = 0;
+ ts_st->pcr_packet_count++;
+ if (ts_st->pcr_packet_count >=
+ ts_st->pcr_packet_period) {
+ ts_st->pcr_packet_count = 0;
write_pcr = 1;
}
}
@@ -1236,7 +1252,7 @@ static void mpegts_write_pes(AVFormatContext *s, AVStream *st,
}
if (key && is_start && pts != AV_NOPTS_VALUE) {
// set Random Access for key frames
- if (ts_st->pid == ts_st->service->pcr_pid)
+ if (ts_st->pcr_packet_period)
write_pcr = 1;
set_af_flag(buf, 0x40);
q = get_ts_payload_start(buf);
--
2.16.4
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