Vorbis dev - Apr 2004 - Given ONLY an ogg packet, can one be able to decode the packet to PCM?

Given ONLY an ogg packet, can one be able to decode the packet to PCM?

And how ogg vorbis know the info of it (bitrate..etc) in order to decode it?

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Kenji Chan wrote:
> Given ONLY an ogg packet, can one be able to decode the packet to PCM?
>
> And how ogg vorbis know the info of it (bitrate..etc) in order to 
> decode it?
>
The vorbis codec requires several header packets for initialization 
before it can decode any packets with audio information.  These header 
packets give the sample rate, number of channels, and the specific 
codebooks.

More details are explained in: 
http://www.xiph.org/ogg/vorbis/doc/vorbis-spec-intro.html


---
Stan Seibert

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On Tuesday 13 April 2004 06:27, Kenji Chan wrote:
> Given ONLY an ogg packet, can one be able to decode the packet to PCM?
>
> And how ogg vorbis know the info of it (bitrate..etc) in order to decode
> it?
An ogg packet is just a generalised chunk of binary data - it has no meaning 
by itself. Do you mean a 'vorbis packet'? If so, the answer is no -
vorbis
requires the header packets (of which there are 3; the second is metadata and 
is not crucial) to allow decode.

Mike

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