[Cin] FFmpeg 4.3 mpegts patch - questions ....
Good Guy
good1.2guy at gmail.com
Mon Jul 13 20:19:20 CEST 2020
Kind of you to take this level of interest,
Well, I don't understand it, just worried about GROWING diff between
> original ffmpeg and Cin's version of it in this area.
>
Me too... The purpose of this patch is to make a samsung (model UBD-K8500)
dvd player accept
the resulting bluray data from the create_bd operation. There are 3 main
differences the patch
attempts to introduce to the default operation.
1) suppress sdt output.
2) refactor pmt,pat packet scheduling.
3) add audio packet priority bit.
The commercial dvd player seems to be sort of actually damaged in that it
will fail
in a variety of bizarre ways if you stray even slightly from a design that
seems to
belong to the priesthood of bluray specs, unpublished and spoken only in
prayer.
I did try the current implementation, with a small tweak to suppress the
sdt output.
This attempt was to use the new packet design scheduling and I did notice
that the audio priority bit is now being applied.
libaformat/mpegtsenc.c:1345
if (ts->m2ts_mode && st->codecpar->codec_id == AV_CODEC_ID_AC3)
val |= 0x20;
This attempt failed, as the dvd player only played media once, and skipped
a bunch of audio
at the beginning. Once it stopped before reaching the end of media. The
unit has to be
power cycled before another experiment can be tried. It is not clear what
the issues are.
The original 5.1 mod still works, and the new mod is backed out until it
can be repaired.
I use this equipment, and I think it is representative of the devices in
the real world.
It is difficult to even find bluray media that is un-encrypted that can be
played on this
commercial player. The un-encrypted media can serve as a template to
create bd media.
https://download.blender.org/durian/movies/
The current ffmpeg mpegtsenc implementation may be more aimed at broadcast
data and not bd dvd system streams, but it is not clear to me just exactly
what it is
that the current encoder targets. I have never had good luck with sending
mods to
just about anyone. Mostly, they scoff and reject the mods with prejudice.
as far as I understand those (onid, tsid) used donwstream:
> was it just for shortening typing time?
> Hm, it think major point in 4.3 was exactly
> - Support for muxing pcm and pgs in m2ts
> ? (PGS are Blu-Ray subtitle graphics - no encoder in ffmpeg yet. But
> probably you can remux the from existing track?)
>
Those mods are mostly to make the pat,pmt,std presentation match the
order/timing
in the sintel example. It is not clear why these are important. It has
been my experience
that many commercial drivers are pretty sad implementations designed for
first to market
gains, and frequently are quite touchy. If the packets are not processed
by a state machine,
then the exact order becomes very important. I am not sure if this is the
case here, but it is
clear that the device is very touchy, and gets confused and stays confused
fast.
This code:
> } while (p < buf_end && (state & 0x1f) != 9 &&
> (state & 0x1f) != 5 && (state & 0x1f) != 1);
>
specializes h264 data and seems to recondition the data. Probably not a
good idea.
The encoder should supply the data to the muxer in good to go condition.
If the ffmpeg implementation worked on my bd player, I definitely would use
it.
Carrying mods is a pain in the butt.
gg
On Sun, Jul 12, 2020 at 11:41 PM Andrew Randrianasulu via Cin <
cin at lists.cinelerra-gg.org> wrote:
>
> src on cgit:
>
>
> https://git.cinelerra-gg.org/git/?p=goodguy/cinelerra.git;a=blob;f=cinelerra-5.1/thirdparty/src/ffmpeg-4.3.patch2;h=81cae5e66d85d3c089603a5a6425cd165aa9f16e;hb=HEAD
>
> Well, I don't understand it, just worried about GROWING diff between
> original ffmpeg and Cin's version of it in this area.
>
> (added Marton as CC, as current maintainer of this area of code - sorry
> for my cont. ignorance, Marton!)
>
> @@ -76,11 +77,12 @@
> MpegTSSection pat; /* MPEG-2 PAT table */
> MpegTSSection sdt; /* MPEG-2 SDT table context */
> MpegTSService **services;
> - int64_t sdt_period; /* SDT period in PCR time base */
> - int64_t pat_period; /* PAT/PMT period in PCR time base */
> + int64_t sdt_packet_timer, sdt_packet_period;
> + int64_t pat_packet_timer, pat_packet_period;
> int nb_services;
> - int64_t first_pcr;
> - int64_t next_pcr;
> + int onid;
> + int tsid;
>
> as far as I understand those (onid, tsid) used donwstream:
>
> @@ -259,7 +257,7 @@
> put16(&q, service->sid);
> put16(&q, 0xe000 | service->pmt.pid);
> }
> - mpegts_write_section1(&ts->pat, PAT_TID, ts->transport_stream_id,
> ts->tables_version, 0, 0,
> + mpegts_write_section1(&ts->pat, PAT_TID, ts->tsid,
> ts->tables_version, 0, 0,
>
>
> was it just for shortening typing time?
>
> @@ -90,14 +92,14 @@
> int service_type;
>
> int pmt_start_pid;
> + int pcr_start_pid;
> int start_pid;
> int m2ts_mode;
> - int m2ts_video_pid;
> - int m2ts_audio_pid;
> - int m2ts_pgssub_pid;
> - int m2ts_textsub_pid;
> + int64_t ts_offset;
>
>
> Hm, it think major point in 4.3 was exactly
>
> - Support for muxing pcm and pgs in m2ts
>
> ? (PGS are Blu-Ray subtitle graphics - no encoder in ffmpeg yet. But
> probably you can remux the from existing track?)
>
>
> @@ -217,14 +217,15 @@
> /* mpegts writer */
>
> #define DEFAULT_PROVIDER_NAME "FFmpeg"
> -#define DEFAULT_SERVICE_NAME "Service"
> +#define DEFAULT_SERVICE_NAME "Service01"
>
>
> Was it required from your Blu-Ray Disk player? May be it can be made
> conditional on new m2ts_b (say) mode?
>
>
> -/* we retransmit the SI info at this rate */
> +/* we retransmit the SI info at this rate (ms) */
> #define SDT_RETRANS_TIME 500
> #define PAT_RETRANS_TIME 100
> -#define PCR_RETRANS_TIME 20
> +#define PCR_RETRANS_TIME 50
>
> may be comment improvement can be made into standalone patch?
>
> @@ -281,148 +279,6 @@
> *q_ptr = q;
> }
>
> -static int get_dvb_stream_type(AVFormatContext *s, AVStream *st)
> [..]
> -static int get_m2ts_stream_type(AVFormatContext *s, AVStream *st)
>
> here whole two functions are gone ..
>
> and probably replaced by homegrown one a bit downstream:
>
> @@ -472,8 +320,72 @@
> err = 1;
> break;
> }
> -
> - stream_type = ts->m2ts_mode ? get_m2ts_stream_type(s, st) :
> get_dvb_stream_type(s, st);
> + switch (st->codecpar->codec_id) {
>
>
> any reason for this move?
>
> @@ -736,7 +648,7 @@
> int i, running_status, free_ca_mode, val;
>
> q = data;
> - put16(&q, ts->original_network_id);
> + put16(&q, ts->onid);
>
>
> again, just shorter to type?
>
> @@ -802,49 +714,12 @@
> return 0;
> }
>
> -static int64_t get_pcr(const MpegTSWrite *ts, AVIOContext *pb)
>
> -static void write_packet(AVFormatContext *s, const uint8_t *packet)
>
> -static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
>
> all three gone .... can they stay ? :}
> (for reducing diff size)
>
> static MpegTSService *mpegts_add_service(AVFormatContext *s, int sid,
> - const AVDictionary *metadata,
> - AVProgram *program)
> + const char *provider_name,
> + const char *name)
> {
> MpegTSWrite *ts = s->priv_data;
> MpegTSService *service;
> - AVDictionaryEntry *title, *provider;
> - char default_service_name[32];
> - const char *service_name;
> - const char *provider_name;
> -
> - title = av_dict_get(metadata, "service_name", NULL, 0);
> - if (!title)
> - title = av_dict_get(metadata, "title", NULL, 0);
> - snprintf(default_service_name, sizeof(default_service_name),
> "%s%02d", DEFAULT_SERVICE_NAME, ts->nb_services + 1);
> - service_name = title ? title->value : default_service_name;
> - provider = av_dict_get(metadata, "service_provider", NULL, 0);
> - provider_name = provider ? provider->value : DEFAULT_PROVIDER_NAME;
>
>
> I think this one allowed more data passing from ...upper libavcodec layer?
>
> -static void enable_pcr_generation_for_stream(AVFormatContext *s, AVStream
> *pcr_st)
> +static void mpegts_prefix_m2ts_header(AVFormatContext *s)
> {
> MpegTSWrite *ts = s->priv_data;
> - MpegTSWriteStream *ts_st = pcr_st->priv_data;
> -
> - 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 {
> - /* 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);
> - if (!frame_size) {
> - av_log(s, AV_LOG_WARNING, "frame size not set\n");
> - frame_size = 512;
> - }
> - frame_period = av_rescale_rnd(frame_size, PCR_TIME_BASE,
> pcr_st->codecpar->sample_rate, AV_ROUND_UP);
> - } else if (pcr_st->avg_frame_rate.num) {
> - frame_period = av_rescale_rnd(pcr_st->avg_frame_rate.den,
> PCR_TIME_BASE, pcr_st->avg_frame_rate.num, AV_ROUND_UP);
> - }
> - if (frame_period > 0 && frame_period <= PCR_TIME_BASE / 10)
> - ts_st->pcr_period = frame_period * (PCR_TIME_BASE / 10 /
> frame_period);
> - else
> - ts_st->pcr_period = 1;
> + if (ts->m2ts_mode) {
> + uint32_t tp_extra_header = ts->pcr % 0x3fffffff;
> + tp_extra_header = AV_RB32(&tp_extra_header);
> + avio_write(s->pb, (unsigned char *) &tp_extra_header,
> + sizeof(tp_extra_header));
> }
> -
> - // output a PCR as soon as possible
> - ts_st->last_pcr = ts->first_pcr - ts_st->pcr_period;
> }
>
> May be just leave old function the same, just add short new one
> (static void mpegts_prefix_m2ts_header(AVFormatContext *s)) ?
>
> same for
>
> -static void select_pcr_streams(AVFormatContext *s)
> +static void section_write_packet(MpegTSSection *s, const uint8_t *packet)
>
> static int mpegts_init(AVFormatContext *s)
>
> ah, so av_dict_get and co moved here ....
>
> - /* MPEG pid values < 16 are reserved. Applications which set
> st->id in
> - * this range are assigned a calculated pid. */
> - if (st->id < 16) {
> - if (ts->m2ts_mode) {
> - switch (st->codecpar->codec_type) {
> - case AVMEDIA_TYPE_VIDEO:
> - ts_st->pid = ts->m2ts_video_pid++;
> + 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;
> - case AVMEDIA_TYPE_AUDIO:
> - ts_st->pid = ts->m2ts_audio_pid++;
> - break;
> - case AVMEDIA_TYPE_SUBTITLE:
> - switch (st->codecpar->codec_id) {
> - case AV_CODEC_ID_HDMV_PGS_SUBTITLE:
> - ts_st->pid = ts->m2ts_pgssub_pid++;
> - break;
> - case AV_CODEC_ID_HDMV_TEXT_SUBTITLE:
> - ts_st->pid = ts->m2ts_textsub_pid++;
> - break;
> - }
> - break;
> - }
> - if (ts->m2ts_video_pid > M2TS_VIDEO_PID + 1 ||
> - ts->m2ts_audio_pid > M2TS_AUDIO_START_PID + 32 ||
> - ts->m2ts_pgssub_pid > M2TS_PGSSUB_START_PID + 32 ||
> - ts->m2ts_textsub_pid > M2TS_TEXTSUB_PID + 1 ||
> - ts_st->pid < 16) {
> - av_log(s, AV_LOG_ERROR, "Cannot automatically assign
> PID for stream %d\n", st->index);
> - return AVERROR(EINVAL);
> }
> - } else {
> - ts_st->pid = ts->start_pid + i;
> }
> - } else {
> - ts_st->pid = st->id;
> }
>
> Oh, here our subtitle support go .......
>
> a lot of skipped, I'm very unsure about all those changes ...
>
>
> @@ -1724,7 +1585,7 @@
>
> ret = avio_open_dyn_buf(&ts_st->amux->pb);
> if (ret < 0)
> - return ret;
> + return AVERROR(ENOMEM);
>
> seems like possible standalone patch for ffmpeg upstream inclusion?
>
> @@ -1755,7 +1616,7 @@
> } while (p < buf_end && (state & 0x7e) != 2*35 &&
> (state & 0x7e) >= 2*32);
>
> - if ((state & 0x7e) < 2*16 || (state & 0x7e) >= 2*24)
> + if ((state & 0x7e) < 2*16 && (state & 0x7e) >= 2*24)
>
> ???? why it was changed?
>
>
>
> IIRC those changes come from fact ffmpeg's
> mpegts muxer mostly geared towards transmission vs standalone BD creation
> ....
>
> But at least potential for BD text subtitles look interestinge nough
> for keeping looking into this area ...I think.
>
> Also, ffmpeg 4.3.1 was already released, with small fixes:
>
> https://ffmpeg.org/download.html
>
> FFmpeg 4.3.1 "4:3"
> 4.3.1 was released on 2020-07-11. It is the latest stable FFmpeg release
> from the 4.3 release branch,
> which was cut from master on 2020-06-08.
>
>
> It was FAST ......
>
> Also, there is one more patch on ML:
> http://ffmpeg.org/pipermail/ffmpeg-devel/2020-July/266181.html
>
> [FFmpeg-devel] [PATCH] x86/yuv2rgb: fix crashes when storing data on
> unaligned buffers
>
> Regression since fc6a5883d6af8cae0e96af84dda0ad74b360a084 on SSSE3 enabled
> CPUs.
>
> Fixes ticket #8747
>
> -----
>
> END!
> --
> Cin mailing list
> Cin at lists.cinelerra-gg.org
> https://lists.cinelerra-gg.org/mailman/listinfo/cin
>
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