No audio in recordings

Hi

I can't help with a solution, but I would like to revive this rather old thread as it may affect a growing number of users/countries...

I think the problem is missing native support for LATM AAC decoding/demuxing in vdr and possibly in the ffmpeg libraries that it relies on. Apparently streamdev server passes the raw mpeg4+aac stream on without modification, which allows external apps like XBMC to decode the audio themselves.
VDR itself though does not appear to understand the format and simply ignores it all the way down to the channel audio PID and thus in direct viewing and recordings.

Here in Denmark we have a combination of MPEG-2 and MPEG-4 DVB-T channels where the latter use LATM HE-AAC audio. With ubuntu 9.10 and VDR 1.7.10 the MPEG-2 channels just work whereas the MPEG-4 ones lack sound when recorded or played directly with e.g. the xine plugins. When passed through the streamdev plugin they can be played fine with audio in e.g. XBMC just like your experience.
However, the VDR plugin for XBMC is not yet stable, so this is not really a solution in a living room setup.

There's a short thread on a Danish news group touching the subject but with no native VDR solution[1] - use the translate link at the top to get a weird but okay'ish translation.

I expect the same to be the case in all the countries where LATM AAC sound is used. AFAICT this includes at least NZ, DK, NO and PT[2]. However, I do not think it is used much in Germany yet, where most VDR development takes place, so there probably isn't a very big incentive to add the feature.

Perhaps someone with better knowledge about the VDR code internals and external dependencies can elaborate on the issue and any development plans?

Cheers, Jonas

[1] http://groups.google.com/group…a7a11a/fa2e4b707c9530b8?#
[2] http://www.mythtv.org/wiki/HE-AAC

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in vdr mailing list there's a working AAC patch for vdr 1.7.14, you should give that one a try.

Great, it looks like somebody beat me and the solution entered the recent 1.7.15 release!

I'll give it a go ASAP.

Edit:
vdr-1.7.15 improves the situation a lot, but I still can't get the final bits right.
Now VDR does handle the audio part of the stream including recordings and all, so the problem of the original poster may be solved. You probably have to rescan channels to get the program IDs right.

I still can't get the LATM AAC audio working using the xine frontends, though.
The audio works if I connect e.g. vlc to the raw xineliboutput stream on localhost:37890, so it is probably a decoding problem in the xine/ffmpeg player. Recordings now play with sound in XBMC with the vnsiserver plugin, too.

I found a couple of ffmpeg tickets that indicate missing support for this particular audio encapsulation and encoding:
https://roundup.ffmpeg.org/issue1891
https://roundup.ffmpeg.org/issue244
so maybe it is just a matter of waiting for full ffmpeg support.

Cheers, Jonas