[Theora-dev] FPGA implementation

Robert Brautigam demon at jmind.hu
Tue Jan 18 05:44:21 PST 2005

> > The second page in that file starts at byte 0x46, byte number 0x60 is
> > numer of segments (0xc). Next goes byte number 0x61 with the value 0x32 <
> > 0xFF !
> > The total length of 12 segments is 0xa7f=
> > 32+ff+ff+ff+ff+ff+ff+ff+ff+ff+ff+57 (bytes 0x61..0x6c)
> The last segment lacing value for a *packet* is less than 255, but there 
> can be multiple packets in a page, and packets can span page boundaries. 
> So an initial lacing value of 0x32 indicates that the first 50 bytes of 
> the page data being the belong to one packet, and the remaining 2637 
> bytes to another.

Well it seems to me, I am not the only one, who became a bit confused
about the paging of packets question. Altough it seems pretty obvious
after one has it figured out, perhaps somebody could modify the
documentation to contain an explicit sentence (or paragraph) about
multiple packets in a single page. 
The paging (ascii) example does not contain such a situation, and there
are no examples anywhere about this (in the specification).
It's not a big issue, but as somebody who has coded an ogg codec from
scratch, this was the only part which was not totally clear after
reading the specification.


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