[vorbis] some more Spec questions

[Sebastian Gesemann]

Hi !

once again.... WITH quotes from the spec ;)

Floor 0 format - header decode
------------------------------
- Step 7: how could any of those values be less than zero
  if i read them as unsigned integers ?

the spec says:
|  1) [floor0_order] = read an unsigned integer of 8 bits
|  2) [floor0_rate] = read an unsigned integer of 16 bits
|  3) [floor0_bark_map_size] = read an unsigned integer of 16 bits
|  4) [floor0_amplitude_bits] = read an unsigned integer of six bits
|  5) [floor0_amplitude_offset] = read an unsigned integer of eight
|     bits
|  6) [floor0_number_of_books] = read an unsigned integer of four
|     bits and add 1
|  7) if any of [floor0_order], [floor0_rate],
|     [floor0_bark_map_size], [floor0_amplitude_bits], 
|     [floor0_amplitude_offset] or [floor0_number_of_books] are
|     less than zero, the stream is not decodable
|  8) array [floor0_book_list] = read a list of [floor0_number_of_books] 
|     unsigned integers of eight bits each;

If one implements it that way, step 7 will never return a 
'stream_undecodable_exception' because of the always positive
values.
Just want to know how I should do this kind of consistency
check.... how it is supposed to be.

<p>Floor 0 format - curve computation
----------------------------------

I'm not going to quote all the stuff here, but have a look
at http://www.xiph.org/ogg/vorbis/doc/vorbis-spec-floor0.html
paragraph: "curve computation" (right in the middle)

| 1) [i] = 0
| :
| :
|    3) calculate [p] and [q] according to
|       http://www.xiph.org/ogg/vorbis/doc/oddlsp.png
| :
| :
|    4) calculate [p] and [q] according to
|       http://www.xiph.org/ogg/vorbis/doc/evenlsp.png
| :
| :

> - The formulas for p and q make use of omega, but there's
>   nothing in the spec about omega... How is omega related
>   to [i] or to ([map] element [i]) ? 

perhaps omega = pi * map[i] / bark_map_size ?

<p>PS: I can't write a patch for the doc if i don't know how it's
supposed to be.

<p>bye,
Sebastian

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