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According to these pages, it seems that PCMWAVEFORMAT has been superseded by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@crosswinds.net
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