[vorbis-dev] Decompression error with two streams.

[Lars Brubaker]

> It could simply be a bug the other usage never tripped (e.g., Vorbis is
> putting out variable sized buffers which .raw and .wav would probably
> not).
> 
> That's not to say it isn't a Vorbis bug, just that 'it never broke
> before' isn't really a strong argument for anything.

Your right, it absolutely isn't a proof that the bug is in Vorbis.
But this code has at least seemed solid for a long time.  
Do you have a test in which Vorbis decompresses two streams in the same 
thread repeatedly in which you can listen to both sounds?  

> 
> > 	return (pOggSoundReader->m_pFile->Read(ptr, size * nmemb) / size);
> 
> I'm sure it's the case, but nothing else is touching that FILE * pointer
> under any conditions, correct?

You are correct, nothing else touches these sounds.  I have tried fairly
exhaustively to make sure that there was no error condition in the file
code or any errors reported from Vorbis.

> 
> Anyway, the code in the COggSoundReader class looked good.  
> 
> I assume that the content you're mixing plays back fine when decoded
> one stream at a time and that the failure is not repeatable (e.g., same
> streams, but not same failure point each time)?  Have you set up any
> means to capture/inspect the results directly from decode?

Absolutely correct.  I have never heard an error with only one stream and
the error occurs intermittently and in different spots within the sound.
This is an argument against some strange alignment problem in the read:
Vorbis is always giving 4k chunks until the end of the sound and our file 
library handles loading everything else in the game regardles of their
size.

> 
> I've not seen any Vorbis failure along the lines you describe (yet),
> and I doubt we'll find the problem simply by looking at code without
> significantly narrowing the search scope first.

If you would like me to test something I'll help in anyway that I can.
At this point we are going to be code releasing very soon and will likely
just live with any bugs that we have.  But I would love to help find this
for the sake of the library (if it even is a bug in the library :).

Lars

--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.