The MPEG-TS muxer will mux streams with unsupported codec id
as a private data stream; this usually makes the stream
not recognizable by ffmpeg and likely other tools.
It is not uncommon to find code where the caller thinks to know better
what the return value should be than the callee. E.g. something like
"if (av_new_packet(pkt, size) < 0) return AVERROR(ENOMEM);". This commit
changes several instances of this to instead forward the actual error.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This sets the range of the first automatically assigned PMT PID or elementary
stream PID parameters to [0x20, 0x1ffa]. You can still assign manually a PID
for a stream using AVStream->id in the wider [0x10, 0x1ffe] range as specified
by ISO13818-1. But since DVB and ATSC both reserves some PIDs, let's not allow
them to be automatically assigned.
Also make sure that assigned PID numbers are valid and fix the error message
for the previous PID collision checks.
Signed-off-by: Marton Balint <cus@passwd.hu>
7d097a0fc5 had the same purpose as
3700f655c5 but the former is much simpler, so
let's remove the latter.
Unfortunately both checks were wrong, because in order to make sure DTS > PCR
we have to give us some headroom, so instead of using a dts_difference <
max_delay check let's use a dts_difference < max_delay/2 check.
Fixes DTS < PCR errors with this command line:
./ffmpeg -loglevel verbose -y -f lavfi -i \
"testsrc=s=64x64:d=20,split=2[out0][tmp1];[tmp1]vflip[out1];sine=d=20,asetnsamples=1000[out2]" \
-flags +bitexact -fflags +bitexact -sws_flags +accurate_rnd+bitexact \
-codec:v libx264 -codec:a mp2 -b:a 32k -pix_fmt yuv420p \
-map '0✌️0' \
-map '0✌️1' \
-map '0🅰️0' \
-muxrate 800000 \
-program st=0:st=2 -program st=1:st=2 -program st=2 -program st=0 -f mpegts out1.ts
Signed-off-by: Marton Balint <cus@passwd.hu>
The packet counting based approach caused excessive sdt/pat/pmt for VBR, so
let's use a timestamp based approach instead similar to how we emit PCRs.
SDT/PAT/PMT period should be consistent for both VBR and CBR from now on.
Also change the type of sdt_period and pat_period to AV_OPT_TYPE_DURATION so no
floating point math is necessary.
Fixes ticket #3714.
Signed-off-by: Marton Balint <cus@passwd.hu>
PCR generation was based on counting packets for both CBR and VBR streams.
Couting packets might have worked for CBR streams (when muxrate was specified)
but it only took into account the packets of a service (or the packets of the
PCR stream lately), so even that was problematic for multi program streams.
The new code works on actual timestamps for both CBR and VBR streams. For VBR
streams the behaviour of the old code is simulated by selecting a PCR interval
which is the highest multiple of the frame duration but still less than 100 ms.
It should be trivial to add support for setting the PCR interval for VBR
streams as well in a later patch.
The accuracy of PCR packets for CBR streams was greatly improved by preemtively
sending them at PCR intervals even if sending the payload of another stream
is in progress.
This may fix these tickets:
- #5750
- #7524
Signed-off-by: Marton Balint <cus@passwd.hu>
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✌️0' \
-map '0✌️1' \
-map '0🅰️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@passwd.hu>
This improves compatibility with some consumer (LG WebOS) TVs which apparently
search a HEVC descriptor (which our mpegts muxer can't generate) or a format
identifier.
Since the HEVC format identifier is not registered (but used in the wild), it is
not written if strict_std_compliance is higher than normal.
This fixes the issue in ticket #7744.
Signed-off-by: Marton Balint <cus@passwd.hu>
This allows remuxing streams from one mpegts container to another,
without requiring avformat_find_stream_info() (or using `ffmpeg
-probesize 32` on the cli).
Signed-off-by: Aman Gupta <aman@tmm1.net>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This is required since some programs are not able to correctly recognize
the metadata. See H.222, 2.6.58 Metadata pointer descriptor.
putstr8() is modified in order to allow to skip writing the string
length.
This avoids continuity check failures in concatenated streams
Reviewed-by: Steven Liu <lingjiujianke@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Set the stream_id to 0xbd (private_stream_id_1). Tools seem to assume
that value, and this is consistent with MPEG TS specification (ITU-T
H.222.0 section 2.12.3).
This allows to copy information related to the stream ID from the demuxer
to the muxer, thus allowing for example to retain information related to
synchronous and asynchronous KLV data packets. This information is used
in the muxer when remuxing to distinguish the two kind of packets (if the
information is lacking, data packets are considered synchronous).
The fate reference changes are due to the use of
av_packet_merge_side_data(), which increases the size of the output
packet size, since side data is merged into the packet data.
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.
In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.
There are multiple important problems with this approach:
- the fields in AVCodecContext are in general one of
* stream parameters
* codec options
* codec state
However, it's not clear which ones are which. It is consequently
unclear which fields are a demuxer allowed to set or a muxer allowed to
read. This leads to erratic behaviour depending on whether decoding or
encoding is being performed or not (and whether it uses the AVStream
embedded codec context).
- various synchronization issues arising from the fact that the same
context is used by several different APIs (muxers/demuxers,
parsers, bitstream filters and encoders/decoders) simultaneously, with
there being no clear rules for who can modify what and the different
processes being typically delayed with respect to each other.
- avformat_find_stream_info() making it necessary to support opening
and closing a single codec context multiple times, thus
complicating the semantics of freeing various allocated objects in the
codec context.
Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
Marton Balint
Gyan Doshi
Andreas Rheinhardt
Jun Zhao
Artyom Lebedev
Aman Gupta
Derek Buitenhuis
Clément Bœsch
Lou Logan
Michael Niedermayer
Stefano Sabatini
Diego Biurrun
Rodger Combs
Sylvain Laurent
Francois Cartegnie
James Almer
Vittorio Giovara
smallishzulu
Carl Eugen Hoyos
Anton Khirnov