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Audio Codec: PCM S24 BE (in24) does not play

Posted: 23 Oct 2013 22:50
by thedreadpirate
Hello,

I have some video recorded with a CineDeck RX SW ver. 4.20 and the audio does not play correctly. The audio sounds only like a series of clicks, seems to be approximately 6 clicks per second. The files are ProRes Proxy (MOV wrapper) and H264 (MOV wrapper).

For the files that don't work, Codec is: PCM S24 BE (in24).

Some slightly older files (from an earlier CineDeck software version) use Codec PCM S24 LE (sowt) and their audio plays just fine. Same behavior on release version 2.1.0 and nightly build from 2013-10-13 ((in24) does not work, (sowt) does). Both sets of files play properly in QuickTime Player 7.7.4.

I am pursuing CineDeck to set their record format back to PCM S24 LE (sowt) audio, but is there any way to support the PCM S24 BE (in24) codec in VLC?

I can make a sample file if necessary. Current files are 4+ gb.

Other possibly relevant information:
Macbook Pro 13" running
Windows 7 Professional SP1
Intel Core 2 Duo P8800@2.66Ghz
8.00 GB RAM
64-bit OS

Thanks very much,

Re: Audio Codec: PCM S24 BE (in24) does not play

Posted: 28 Oct 2013 20:04
by thedreadpirate
I made a demo file to show this problem. The original file is video bars with some ambient noise/talking in the background. The audio is encoded in PCM S24 LE (sowt). The file is here:

https://www.dropbox.com/s/72qzsr1l6dbsn ... 9audio.mov

This second file is exactly the same content, re-encoded on a CineDeck RX in H264 proxy format with audio encoded as PCM S24 BE (in24). The audio only plays as a series of clicks. The file is here:

https://www.dropbox.com/s/iwmwvxikuef00 ... 9audio.mov

Could somebody (maybe on a non-windows platform) confirm that they have this same problem iwth the (in24) encoded audio?

Are we to the point where I should file this as a bug in VLC?

Thanks,

Re: Audio Codec: PCM S24 BE (in24) does not play

Posted: 28 Oct 2013 21:05
by RĂ©mi Denis-Courmont
Decoding that file does fail on Linux and shows a lot of timestamp errors. But decoding S24 BE as such seems to work just fine. So this may be a problem with the MP4 demuxer (or with CineDeck).

Re: Audio Codec: PCM S24 BE (in24) does not play

Posted: 29 Oct 2013 21:06
by thedreadpirate
So.... Is there a way to isolate whether this is a problem with VLC for Windows or non-standard encoding on the part of the Cinedeck? If it's a problem with VLC for Windows, I will file a bug report there and things will proceed as they do. If I can demonstrate that the Cinedeck is recording out-of-standard, then I may be able to push them towards changing the software there.

Thanks,