[vorbis-dev] what script or command makes the codebooks?

Gregory Maxwell greg at linuxpower.cx
Sun Dec 17 21:30:39 PST 2000



On Sun, Dec 17, 2000 at 11:07:28PM -0600, Mike Coleman wrote:
> Gregory Maxwell <greg at linuxpower.cx> writes:
> > No. It's easy to generate training data, it's just a define in the source.
> 
> Yeah, but I'm trying to see exactly how these particular codebooks were
> produced.  (Actually, it would be kind of nice if each .vqh file included a
> "pedigree" inside a comment that described exactly how it was produced (args,
> etc), and maybe even gave a list of training data sources together with
> md5sums.

They almost do, nothing that nice though.. Their params (in the vqhs) and
the training set is all you need to reproduce them. 

The process runs the data through several commands, so its hard to track the
data and it's assume that you know what you are doing if you are using those
tools. :)

Steps, in rough,

Change #if 0 in lib source to make it generate training data,

Train the LSP data (no info here because I havn't done it since Vorbis
switched to lattice for LSP).

Regenerate training data with LSP books because residue is affected by LSP
books.

Run residue training data into residuesplit (parms in mode_*.h but not
stated in an obvious way), which splits the residue into partitions.

Lattice build each partition (parms can be extracted from the vqhes).

Latticepare, to reduce for targeted bitrate.

Huffbuild to produce, aux book.

Latticehint the books.

It's been some time, so sorry I havn't been much help.. :( But with Monty
very busy, I figured something is better then nothing..

--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.



More information about the Vorbis-dev mailing list