[vorbis-dev] A broken WAV header?

[hermit]

Hi,

While I browsing the source of the Oggenc utility, I saw a comment says:

 /* A common error is to have an 18-byte format chunk with the last two
  * bytes 0. This is incorrect, but sufficiently common that we only warn
  * about it instead of refusing it.
  * Please, if you have a program that's creating these 18 byte chunks, send
  * a bug report to whoever makes it
  */

And it was assuming a 16-byte strucuture(PCMWAVEFORMAT) in a file in later
code.

But why?
I think the 18-byte structure in the comment is probably WAVEFORMATEX....
And here's links where the Platform SDK mentions about these structures:
(URLs may be broken into a few lines)

PCMWAVEFORMAT:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/multimed/hh
/multimed/mmstr_7gtu.asp

WAVEFORMATEX:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/multimed/hh
/multimed/mmstr_625u.asp

According to these pages, it seems that PCMWAVEFORMAT has been superseded by
WAVEFORMATEX?
And 0's for the last 2 bytes are allowed (cbSize) when the data is PCM.

So, the comment sounds a bit weird to me... =)

And there seems like the Oggenc gives a warning about 'fact' chunk in a
file,
but all the applications that produce WAV file must include it, IIRC.
(mentioned in a comment in the old ACMAPP sample application?)

But many applications ignoring, though. =)

Any comments?
Thanks.

hermit.

---
MAIN: hermit14 at crosswinds.net

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