[Vorbis-dev] Question about the identification header

[Ralph Giles]

On Thu, Jul 28, 2005 at 07:48:03PM +0200, Simon OUALID wrote:

> Those bytes are located between the end of the identification header 
> (after the framing flag bit), and the comment header (at the 0x03, 
> following by the 'vorbis' bytes).

This is most likely the Ogg page header. Ogg is the usual the 
encapsulation format for Vorbis audio data. You can read more
about it here:

    http://xiph.org/ogg/doc/framing.html
    http://ietf.org/rfc/rfc3533.txt

You're correct that there's a packet length field in there (unary 
encoding) but also sequencing information, a timestamp, and a CRC.
You'll have to implement updating at least the CRC and length fields
to properly write out updated headers.

Hope that helps,
 -r