LAV Filters - DirectShow Media Splitter and Decoders - Page 1087

sneaker_ger · 9th April 2017, 00:18

ffmpeg decoder doesn't decode eac3 substreams. You have to bitstream or use a different decoder. Activate "Use legacy 5.1 channel layout" to output back instead side.

max79 · 9th April 2017, 00:28

to sneaker_ger:
I think you are wrong! Look at my pic from my SR-#7: Codec = eac3. All DD+ audio files with 5.1ch plays fine! Problem only with DD+ 7.1ch.

huhn · 9th April 2017, 06:25

looks like an ffmpeg limitation: https://trac.ffmpeg.org/ticket/4608
bitstreaming should work fine.

adding attachments doesn't mean we can see them.

nevcairiel · 9th April 2017, 08:37

Please test these streams with ffmpeg, if it outputs 5.1 there, then you should report the problem there. LAV just uses ffmpeg for decoding, it doesn't implement its own decoders.
As sneaker_ger has said, dependent substreams (ie. as found on Blu-ray EAC3 tracks) are not supported, which is often used for 7.1

PS:
"Side" is the default 5.1 surround channel for Dolby codecs.

nevcairiel · 9th April 2017, 08:55

Quote:

Originally Posted by Helios61

Hi @nevcairiel, Hi @all
I've noticed a lot of audio dropouts while playback of live tv (DVB/C) in Mediaportal with RTL TV, only the AC3 stream. With other stations and MPEG audio streams all is working fine. LAV Audio AC3 bitstreaming is configured in MediaPortal 1.
Testfile ->Link<-

The stream seems to be broken (the frame CRCs don't match on the audio frames with glitches). Did you have bad reception when recording it?

max79 · 9th April 2017, 10:36

to huhn:
Sorry. I didn't know. Now i'm fix that.

sneaker_ger · 9th April 2017, 10:39

You can't fix attachments. A moderator needs to approve them manually and that often takes days. That's why most people here upload to external hosters instead. (like imgur.com, abload.de for images or sendspace.com, mediafire.com, mega.nz for other files)
But in this case we probably don't need your screenshots. You know it's an ffmpeg feature limitation.

max79 · 12th April 2017, 11:51

to nevcairiel:
I'm checked. In v0.69.0.20-git my SUPPORT REQUEST - #1 still did not fixed...

nevcairiel · 12th April 2017, 11:53

Repeatedly asking will also not fix it. LAV Filters is provided "as is", I cannot fix every obscure use-case immediately, sorry.
Feel free to send a patch that fixes it.

Helios61 · 12th April 2017, 17:05

Quote:

Originally Posted by nevcairiel

The stream seems to be broken (the frame CRCs don't match on the audio frames with glitches). Did you have bad reception when recording it?

It is german Unitymedia cable TV. Quality and signal strength are 100%. TV card is Digital Devices cine DVB-C/C2/T2.

nevcairiel · 12th April 2017, 17:43

Well, the stream still appears to be corrupt, the checksums don't match for a bunch of audio frames. Can't really try to improve playback if the first message i get is wrong frame checksums - who knows what happened to the stream exactly.

manolito · 12th April 2017, 19:20

@Helios61

Your stream is MPEG2-TS, and these streams ALWAYS need to be converted to PS elementary streams (with PropjectX or PVAStrumento. I prefer ProjectX).

I ran your file through ProjectX, and for the AC3 stream there were many complaints about missing sync words. But after ProjectX had repaired the audio and I remuxed it to an MPEG2 program stream it played perfectly, no dropouts and no sync problems.

Looks like UnityMedia is sending out corrupt AC3 streams...

Cheers
manolito

manolito · 12th April 2017, 19:28

@nevcairiel

Since the good old DVB-T is history (in Germany), I do have lots of problems with DVB-T2...

I decode the files (mTS container, HEVC video, audio either eac3 or aac-latm) using LAVFilters with DSS2Mod. Basically this works, but it looks like leading B-Frames cannot be decoded. See this post by Mr. Cypheros (TS-Doctor):
https://cypheros.de/forum_ger/index....25288#msg25288

Is this true? I mean, is LAV splitter to blame?

Cheers
manolito

LigH · 12th April 2017, 20:03

Sounds like a usual "open GOP" issue? To support easy channel switching, video streams should be encoded with closed GOPs, I believe; but that reduces efficiency slightly...

sneaker_ger · 12th April 2017, 20:43

Here's a recent sample if needed. Seeking breaks the picture until what I assume is the next keyframe. (And only one program can be used but IIRC that's by design/a known LAV limitation.)
MPC-BE splitter + LAV Video works fine.

nevcairiel · 12th April 2017, 22:13

The FFmpeg TS demuxer does not offer such functionality (it doesn't know what kind of frames are in the stream, since thats codec dependent information and mpeg-ts itself does not carry such flags), and I do not currently plan to work on this myself.
I could maybe hide the frames (like h264 does) if that makes you feel better?

It would still start decoding a "proper" image at the same spot as it does now though.

MPEG-TS is generally not a format you should expect "perfect" seeking on, because the format itself has basically no seeking support. Even finding the appropriate timecode in the file is already a slow process, and with broadcast streams can even be really annoying (ie. with wrap-around).

manolito · 13th April 2017, 00:01

@sneaker_ger

Your sample is even nastier than the files I get from my new Xoro DVBT2 receiver...

MediaInfo reports 7 video and audio streams. Pretty weird already. Repacking it to MKV using the current MKVMerge works without errors, but the resulting MKV does not show any video, neither in VLC nor in DirectShow based players.

Using FFmpeg to repack the file to MKV does work, but I get a nasty A/V sync error. I need to determine the delay manually, taking the values from MediaInfo does not work.

I need to convert my HEVC TV captures to AVC because my streaming box (XTreamer Sidewinder) does not support HEVC, and I desperately need to develop an automatic way to make these conversions. Looks like I got some work ahead of me...

Cheers
manolito

Helios61 · 14th April 2017, 08:35

Quote:

Originally Posted by nevcairiel

Well, the stream still appears to be corrupt, the checksums don't match for a bunch of audio frames.

Quote:

Originally Posted by manolito

Looks like UnityMedia is sending out corrupt AC3 streams...

The issue seems to be over. I didn't have noticed dropouts within the last days.
Big Thanks for yor support @nevcairiel and @manolito

oddball · 14th April 2017, 15:16

I've just reinstalled Windows 10 Creators Update and I can't seem to get subs to NOT display using XYSubFilter with MPC-BE. Normally I put

Code:

eng:eng|f;eng:off;*:eng;*:*

in both the audio and subtitle fields under 'Advanced' in LAV Splitter. But it's not working. Subs are displaying no matter what.

Any ideas?

sneaker_ger · 14th April 2017, 15:30

Do you have "Default track preference" ticked in MPC-BE "Options">"Playback"? It overrides LAV's selection.

P.S.: audio priority is only simple like e.g. "eng,jap,spa" ..., only subtitle field accepts pairs

9th April 2017, 08:37	#21724 \| Link
nevcairiel Registered Developer Join Date: Mar 2010 Location: Hamburg/Germany Posts: 10,347	Please test these streams with ffmpeg, if it outputs 5.1 there, then you should report the problem there. LAV just uses ffmpeg for decoding, it doesn't implement its own decoders. As sneaker_ger has said, dependent substreams (ie. as found on Blu-ray EAC3 tracks) are not supported, which is often used for 7.1 PS: "Side" is the default 5.1 surround channel for Dolby codecs. __________________ LAV Filters - open source ffmpeg based media splitter and decoders Last edited by nevcairiel; 9th April 2017 at 08:47.

12th April 2017, 11:53	#21729 \| Link
nevcairiel Registered Developer Join Date: Mar 2010 Location: Hamburg/Germany Posts: 10,347	Repeatedly asking will also not fix it. LAV Filters is provided "as is", I cannot fix every obscure use-case immediately, sorry. Feel free to send a patch that fixes it. __________________ LAV Filters - open source ffmpeg based media splitter and decoders Last edited by nevcairiel; 12th April 2017 at 11:55.

12th April 2017, 17:43	#21731 \| Link
nevcairiel Registered Developer Join Date: Mar 2010 Location: Hamburg/Germany Posts: 10,347	Well, the stream still appears to be corrupt, the checksums don't match for a bunch of audio frames. Can't really try to improve playback if the first message i get is wrong frame checksums - who knows what happened to the stream exactly. __________________ LAV Filters - open source ffmpeg based media splitter and decoders

12th April 2017, 20:03	#21734 \| Link
LigH German doom9/Gleitz SuMo Join Date: Oct 2001 Location: Germany, rural Altmark Posts: 6,782	Sounds like a usual "open GOP" issue? To support easy channel switching, video streams should be encoded with closed GOPs, I believe; but that reduces efficiency slightly... __________________ New German Gleitz board MediaFire: x264 \| x265 \| VPx \| AOM \| Xvid

12th April 2017, 22:13	#21736 \| Link
nevcairiel Registered Developer Join Date: Mar 2010 Location: Hamburg/Germany Posts: 10,347	The FFmpeg TS demuxer does not offer such functionality (it doesn't know what kind of frames are in the stream, since thats codec dependent information and mpeg-ts itself does not carry such flags), and I do not currently plan to work on this myself. I could maybe hide the frames (like h264 does) if that makes you feel better? It would still start decoding a "proper" image at the same spot as it does now though. MPEG-TS is generally not a format you should expect "perfect" seeking on, because the format itself has basically no seeking support. Even finding the appropriate timecode in the file is already a slow process, and with broadcast streams can even be really annoying (ie. with wrap-around). __________________ LAV Filters - open source ffmpeg based media splitter and decoders Last edited by nevcairiel; 12th April 2017 at 22:18.

9th April 2017, 00:18	#21721 \| Link
sneaker_ger Registered User Join Date: Dec 2002 Posts: 5,565	ffmpeg decoder doesn't decode eac3 substreams. You have to bitstream or use a different decoder. Activate "Use legacy 5.1 channel layout" to output back instead side.

9th April 2017, 00:28	#21722 \| Link
max79 Registered User Join Date: Mar 2017 Posts: 76	to sneaker_ger: I think you are wrong! Look at my pic from my SR-#7: Codec = eac3. All DD+ audio files with 5.1ch plays fine! Problem only with DD+ 7.1ch.

9th April 2017, 06:25	#21723 \| Link
huhn Registered User Join Date: Oct 2012 Posts: 7,926	looks like an ffmpeg limitation: https://trac.ffmpeg.org/ticket/4608 bitstreaming should work fine. adding attachments doesn't mean we can see them.

9th April 2017, 10:36	#21726 \| Link
max79 Registered User Join Date: Mar 2017 Posts: 76	to huhn: Sorry. I didn't know. Now i'm fix that.

9th April 2017, 10:39	#21727 \| Link
sneaker_ger Registered User Join Date: Dec 2002 Posts: 5,565	You can't fix attachments. A moderator needs to approve them manually and that often takes days. That's why most people here upload to external hosters instead. (like imgur.com, abload.de for images or sendspace.com, mediafire.com, mega.nz for other files) But in this case we probably don't need your screenshots. You know it's an ffmpeg feature limitation.

12th April 2017, 11:51	#21728 \| Link
max79 Registered User Join Date: Mar 2017 Posts: 76	to nevcairiel: I'm checked. In v0.69.0.20-git my SUPPORT REQUEST - #1 still did not fixed...

12th April 2017, 19:20	#21732 \| Link
manolito Registered User Join Date: Sep 2003 Location: Berlin, Germany Posts: 3,079	@Helios61 Your stream is MPEG2-TS, and these streams ALWAYS need to be converted to PS elementary streams (with PropjectX or PVAStrumento. I prefer ProjectX). I ran your file through ProjectX, and for the AC3 stream there were many complaints about missing sync words. But after ProjectX had repaired the audio and I remuxed it to an MPEG2 program stream it played perfectly, no dropouts and no sync problems. Looks like UnityMedia is sending out corrupt AC3 streams... Cheers manolito

12th April 2017, 19:28	#21733 \| Link
manolito Registered User Join Date: Sep 2003 Location: Berlin, Germany Posts: 3,079	@nevcairiel Since the good old DVB-T is history (in Germany), I do have lots of problems with DVB-T2... I decode the files (mTS container, HEVC video, audio either eac3 or aac-latm) using LAVFilters with DSS2Mod. Basically this works, but it looks like leading B-Frames cannot be decoded. See this post by Mr. Cypheros (TS-Doctor): https://cypheros.de/forum_ger/index....25288#msg25288 Is this true? I mean, is LAV splitter to blame? Cheers manolito

12th April 2017, 20:43	#21735 \| Link
sneaker_ger Registered User Join Date: Dec 2002 Posts: 5,565	Here's a recent sample if needed. Seeking breaks the picture until what I assume is the next keyframe. (And only one program can be used but IIRC that's by design/a known LAV limitation.) MPC-BE splitter + LAV Video works fine.

13th April 2017, 00:01	#21737 \| Link
manolito Registered User Join Date: Sep 2003 Location: Berlin, Germany Posts: 3,079	@sneaker_ger Your sample is even nastier than the files I get from my new Xoro DVBT2 receiver... MediaInfo reports 7 video and audio streams. Pretty weird already. Repacking it to MKV using the current MKVMerge works without errors, but the resulting MKV does not show any video, neither in VLC nor in DirectShow based players. Using FFmpeg to repack the file to MKV does work, but I get a nasty A/V sync error. I need to determine the delay manually, taking the values from MediaInfo does not work. I need to convert my HEVC TV captures to AVC because my streaming box (XTreamer Sidewinder) does not support HEVC, and I desperately need to develop an automatic way to make these conversions. Looks like I got some work ahead of me... Cheers manolito

14th April 2017, 15:16	#21739 \| Link
oddball Registered User Join Date: Jan 2002 Posts: 1,264	I've just reinstalled Windows 10 Creators Update and I can't seem to get subs to NOT display using XYSubFilter with MPC-BE. Normally I put Code: eng:eng\|f;eng:off;:eng;:* in both the audio and subtitle fields under 'Advanced' in LAV Splitter. But it's not working. Subs are displaying no matter what. Any ideas?

14th April 2017, 15:30	#21740 \| Link
sneaker_ger Registered User Join Date: Dec 2002 Posts: 5,565	Do you have "Default track preference" ticked in MPC-BE "Options">"Playback"? It overrides LAV's selection. P.S.: audio priority is only simple like e.g. "eng,jap,spa" ..., only subtitle field accepts pairs