[tremor] MDCT_lookup tables reduced by one third.

[Monty]

On Wed, Sep 11, 2002 at 11:36:24AM +0200, timmy brolin wrote:
> 
> > By the way... What are the other four trignometric functions in mdct_lookup.h? It's hard to figure them out by just looking att the numbers and curves. (sine/cosine was pretty obvious thou..)
> 
> > Read the paper that describes the original algorithm.  The header on
> > mdct.c isn't lying or anything :-)
> 
> The header on mdct.c might not by lying, but it doesn't tell much truth either.

<p>> I can't find the algorithms for the mdct_lookup tables anywhere, except, as Nicolas Pitre just pointed out,  in the original vorbiscode.

They're in the paper, the 'A', 'B' and 'C' lookups.  If you look at
what the code is doing, step by step, it follows the exact algorithm
in the paper.  Also, libvorbis is, indeed, an obvious place to look
for more information.  You had all the tools at your disposal to figure
it out.

Monty
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