Missing teletext captions

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Jeffos
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Missing teletext captions

Postby Jeffos » 08 Sep 2023 14:59

Hi

The following TS file has some teletext on page 888. VLC only displays "a part of" this teletext.
I think it's a VLC bug because I can see full captions with apps like CCExtractor and AVC Analyzer.

For example, the first caption should be on 2 lines:
to the scene of a huge fire
at a tyre-recycling facility.
but VLC only displays 1 line:
to the scene of a huge fire
<nothing/gap>
Reproduced on both macOS/VLC 3.0.14 and Win/VLC 3.0.18.

TS file: https://mj-s.com/TeletextIssue.ts
Expected teletext output: https://mj-s.com/TeletextIssue.srt (CcExtractor'ed from the above TS file)

Should I fill a bug report?
(tehere are some existing BRs in those lines but their desc are too vague, or talking about "fully missng captions" like https://code.videolan.org/videolan/vlc/-/issues/24690)

Lotesdelere
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Re: Missing teletext captions

Postby Lotesdelere » 09 Sep 2023 12:21

I can't play your file with VLC 3.0.18 although it does play with other players including FFPlay even though the latter gives a lot of error messages:

VLC:

Code: Select all

main debug: `file:///D:/Temp/Samples/TeletextIssue-t%3D163105.ts' successfully opened ts debug: pid[700] unknown ts debug: first packet for pid=700 cc=0x2 ts debug: pid[710] unknown ts debug: pid[701] unknown ts debug: first packet for pid=701 cc=0x5 main error: demux doesn't like DEMUX_GET_TIME ts debug: pid[480] unknown ts debug: first packet for pid=480 cc=0x2 ts debug: pid[702] unknown ts debug: first packet for pid=702 cc=0x4 main error: demux doesn't like DEMUX_GET_TIME ts debug: first packet for pid=0 cc=0x1 ts debug: PATCallBack called ts debug: new PAT ts_id=4369 version=0 current_next=1 ts debug: * number=10 pid=480 ts debug: temporary receiving program 10 main error: demux doesn't like DEMUX_GET_TIME main error: demux doesn't like DEMUX_GET_TIME main error: demux doesn't like DEMUX_GET_TIME main error: demux doesn't like DEMUX_GET_TIME main error: demux doesn't like DEMUX_GET_TIME main error: demux doesn't like DEMUX_GET_TIME main error: demux doesn't like DEMUX_GET_TIME ts debug: first packet for pid=480 cc=0x3 ts debug: PMTCallBack called for program 10 ts debug: new PMT program number=10 version=0 pid_pcr=710 ts debug: * pid=700 type=0x1b AVC video stream as defined in ITU-T Rec. H.264 ts debug: => pid 700 has now es fcc=h264 ts debug: Default program is 10 ts debug: * pid=701 type=0xf ISO/IEC 13818-7 Audio with ADTS transport ts debug: - ES descriptor tag 0xdd ts debug: - ES descriptor tag 0xa ts debug: - ES descriptor tag 0x1c ts debug: - SL/FMC descriptor not found/matched ts debug: found language: eng ts debug: => pid 701 has now es fcc=mp4a ts debug: * pid=702 type=0x6 ISO/IEC 13818-1 PES packets containing private data ts debug: - ES descriptor tag 0x56 ts debug: * ttxt type=Teletext subtitles lan=eng page=888 ts debug: => pid 702 has now es fcc=telx ts debug: * pid=703 type=0x6 ISO/IEC 13818-1 PES packets containing private data ts debug: - ES descriptor tag 0x59 ts debug: => pid 703 has now es fcc=dvbs ts debug: * pid=17 listening for SDT ts debug: enabling pid 700 from program 10 ts debug: enabling pid 701 from program 10 ts debug: enabling pid 702 from program 10 ts debug: enabling pid 703 from program 10 ts debug: enabling pcr pid 710 from program 10 ts debug: EOF at 21482384 main error: demux doesn't like DEMUX_GET_TIME ts debug: first packet for pid=700 cc=0xd ts debug: first packet for pid=701 cc=0xd ts debug: first packet for pid=702 cc=0x7 ts debug: first packet for pid=703 cc=0x4 main debug: slave 0 EOF ts debug: EOF at 21482384 main debug: EOF reached

FFplay:

Code: Select all

[mpegts @ 00000042a2db1a00] PES packet size mismatch= 0B f=0/0 [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 43158937). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 44980537). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 44984137). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 1, dts = 44995894). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 44987737). Input #0, mpegts, from 'D:\Temp\TeletextIssue-t=163105.ts': f=0/0 Duration: 00:00:25.34, start: 475.343744, bitrate: 6782 kb/s Program 10 Stream #0:0[0x2bc]: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 50 tbr, 90k tbn Stream #0:1[0x2bd](eng): Audio: aac (HE-AAC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp, 95 kb/s Stream #0:2[0x2be](eng): Subtitle: dvb_teletext ([6][0][0][0] / 0x0006), 492x250 Stream #0:3[0x2bf](eng): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42780937). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42784537). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42788137). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42791737). [mpegts @ 00000042a2db1a00] PES packet size mismatch [h264 @ 00000042a2e5b0c0] reference picture missing during reorder Last message repeated 1 times [h264 @ 00000042a2e5b0c0] Missing reference picture, default is 2147483647 Last message repeated 1 times [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42820537). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42824137). [h264 @ 00000042a5a64200] mmco: unref short failure Last message repeated 1 times [h264 @ 00000042a5a64200] number of reference frames (0+5) exceeds max (4; probably corrupt input), discarding one [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42827737). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42831337). [mpegts @ 00000042a2db1a00] PES packet size mismatch [mpegts @ 00000042a2db1a00] Packet corrupt (stream = 2, dts = 42834937). [h264 @ 00000042a2e5cbc0] mmco: unref short failure Last message repeated 1 times [h264 @ 00000042a2e5cbc0] number of reference frames (0+5) exceeds max (4; probably corrupt input), discarding one [mpegts @ 00000042a2db1a00] PES packet size mismatch

Jeffos
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Re: Missing teletext captions

Postby Jeffos » 14 Sep 2023 11:26

Thanks for giving it a try Lotesdelere!
!!?
I think you had a download issue (?): as I said, I tested this file on both macOS/VLC 3.0.14 and Win/VLC 3.0.18 and it plays fine (I just cleared my caches and re-downloaded it on both OS just to make sure...). My only issue with this file is about teletext...

Lotesdelere
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Re: Missing teletext captions

Postby Lotesdelere » 14 Sep 2023 14:39

Well, we need a better sample file anyway.

Jeffos
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Re: Missing teletext captions

Postby Jeffos » 14 Sep 2023 17:23

Wow! First a lie, then this! Thanks that helps a lot!

I assume you know how a live-captured TS stream looks like (if not, the errors you posted above are irrelevant).

DVBViewer (with the TS file linked here):
Image

VLC (with the TS file linked here):
Image

All apps I've tried display/extract the teletext correctly, except VLC.
The idea was to ping YOU about a VLC bug (personally I don't care, I'll use DVBViewer for teletext from now on).
Enough time wasted on this for me, so no more uploads, sorry.

Lotesdelere
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Re: Missing teletext captions

Postby Lotesdelere » 15 Sep 2023 10:29

Wow! First a lie, then this!

I beg your pardon ?


the errors you posted above are irrelevant

I've posted what I got on the machine I tested with.


Enough time wasted on this for me, so no more uploads, sorry.

No sample file, no fix.

Jeffos
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Re: Missing teletext captions

Postby Jeffos » 15 Sep 2023 12:46

I beg your pardon ?
"I can't play your file with VLC 3.0.18": not true, it plays fine in VLC 3.0.18, confirmed by some colleagues on various systems.
No sample file, no fix.
But you have a sample file! Sigh. What I'm telling you is that the errors you see are irrelevant to the issue, they are mostly due to the way the file has been captured (e.g. PMT arriving afterwards, etc).

What's going on here is that you think "this dumb guy has posted a crappy file, let's ignore it". Unfortunately, it isn't the case. The file is valid and I know why I'm reporting it, I even have a vague idea of what could trigger the bug: some of these subtitles arrive in 2 steps, e.g.:
PTS n:
to the scene of a huge fire
PTS n+x:
to the scene of a huge fire
at a tyre-recycling facility.

Lotesdelere
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Re: Missing teletext captions

Postby Lotesdelere » 16 Sep 2023 11:35

What's going on here is that you think "this dumb guy has posted a crappy file, let's ignore it".

If I wanted to ignore it I wouldn't even keep on answering.
I could finally play your sample file with VLC, I don't know why it didn't work the first time. Anyway, I can confirm your report, some lines are missing and all of the subtitles seem to be late in sync to be displayed compared to other players.

You should create a new report ticket on the VLC issues tracker with your above report, the link to your sample file and the link to this thread:
https://code.videolan.org/videolan/vlc/-/issues

If possible, because of this:
https://forum.videolan.org/viewtopic.ph ... 27#p538427

Jeffos
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Re: Missing teletext captions

Postby Jeffos » 19 Sep 2023 09:08

Thanks Lotesdelere!
As suspected, I've created aGitLab account like 24h ago but still have no feedback, and I can't login: "Your account is pending approval from your GitLab administrator and hence blocked. Please contact your GitLab administrator if you think this is an error."
In the thread you've quoted, Rémi Denis-Courmont says "new user registration is currently disabled due to excessive spam account creations".


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