[Vorbis-dev] Channels ordering bug

Ivo Emanuel Gonçalves justivo at gmail.com
Sun Jun 8 15:09:40 PDT 2008


On 5/31/08, Ralph Giles <giles at xiph.org> wrote:
> Is there any convention for what the length is in these extended wav
> files? It would be nice if we could handle this automatically, based
> on a magic length, or lack of an EOF, instead of needing an explicit
> option.

Since Jose is not in this list I had to contact him.  His response follows:

 "--ignorelength can't be the default behaviour because after the audio
 data chunk can be other legal chunks encoded like a click noise.

 There are a problem if always ignore the datachunk size and read
 like audio data until end of file.  Is legal add extrachunks after the
 datachunk. In old Golwave versions the cue points was added after the
 audio data. Now WavoSaur write info at end of file also.

 Don't exist conventions about the length when >4GB. In BeHappy I put
 0xFFFFFF00 like data length because is multiple of any blocksize for 1
 to 8 ByteDepth (8-64 bitdepth) and 1 to 8 Channels, Faad also use a fix
 value. But other decoders or Foobar2000 only put the 4 bytes with less
 value, then a 4.2 GB file with 130 min is showed for many soft like 6
 min (130 - 124 ) equivalent to a 0.2 GB wav

 The --ignorelength parameter is a exception to solve a problem until
 formats like w64 or rf64 are more extended."

If there are no objections, I will go ahead and commit his patch.  All right?

-Ivo


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