[Openal] Short question on WAV File Attributes

[Chris Robinson]

On Thursday 12 July 2007 02:05:05 pm Sylvia Yun wrote:
> Hi hopefully this should take a second.  I'm new to understanding the media
> file formats (and the whole openAL thing in general).
>
> I have a basic openAL implementation and it works great for the .wav files
> they provided.  However, when I try to open other .wav files, they won't
> play.
>
> Stepping through the code, it shows that it never loads the data
> (0x00000000) and the size, frequency, etc. remain null (big negative
> numbers).  The only differences I could find between the wav files I could
> play and the ones I couldn't is the file attributes (the ones I can play
> are of type 'A', which I think has something to do with archival... and the
> ones I can't play are 'AN').  They are all in the same folder.
>
> Am I thinking along the right tracks...?  What exactly are the AN and A
> attributes?  All the wav files will play if I play in Yahoo Jukebox or
> Windows Media Player.

The file's attributes shouldn't be much of a problem as long as they're 
readable. Given that WMP can play it, it's sagfe to say it is.

Does WMP say what format the data is? Sometimes people will put MP3 data into 
a .wav file, and OpenAL/ALUT won't read that. It could also be using 
WAVE_FORMAT_EXTENSIBLE, which ALUT also won't also read.

The only formats ALUT can read, apparently, are WAVE_FORMAT_PCM and 
WAVE_FORMAT_MULAW. Other formats, such as MP3, ALAW, and ADPCM, won't work.