[ogg-dev] OggPCM (uncompressed Ogg audio)

Arc arc at Xiph.org
Wed Nov 9 01:10:45 PST 2005

Moved off OggYUV thread as this is off-topic for it..

On Wed, Nov 09, 2005 at 04:51:51PM +0800, illiminable wrote:
> >
> >Um, data packets consist of a 32-bit header followed by PCM data.  Where 
> >did you get the idea that "sync" data was in the packet?
> That's what the first 32 bits of "header" are.

Um, no, the first 32 bits of the header is a packet type ID followed by the 
3-byte codec label.  What part of "\xFFPCM" could possibly be considered sync 

Seriously, I've gotten the strong impression you're arguing from the hip without 
actually reading any of the draft specs we're talking about.

Here's a link, since you've obviously not read it sufficiently:

> >KISS - Keep It Simple, Stupid.  This is a raw data format.  It's value to
> >everyone is primarily how simple it is to implement.
> I don't know whether to laugh or cry. Yes... it's a raw data format... and 
> look at the header you've given it.

Number of channels, bits per sample, samples per second, sample format.. exactly 
what in this would you consider extranious?

The data packet header was given because with Ogg codecs you need a one-byte 
identifier to differentiate a data packet from a header packet, and the "PCM" is 
free because otherwise we'd be buffering out to the next 32-byte word anyway.

Again, I don't know what you've been reading, or if you're seeing the same spec, 
how you could have possibly misunderstood the fairly plain data layout, but this 
is the smallest formatted PCM codec I've seen, especially compared to RIFF/WAVE.

I'm interested in hearing your specific criticisms on this.


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 to allow each to be what she and he can be,
  rests inherently upon the availability of knowledge;
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