[vorbis-dev] mdct

[Segher Boessenkool]

> 
> > Okay, but what are the sizes used _now_?
> 
> 256/2048 right now.  Spec says 64 -> 16384 (or some such) but really, 128->
> 4096 is all we're likely to see.  I may limit the spec to that for the sake of 
> hardware players for the next few years.

I wouldn't limit it to 128; for example, in case of a sharp attack,
we could use a 32/32 window, a 32/256 window, a 256/2048 window. Or
something. i.e., a very short window to catch the spike, a medium window
for the harmonic content, and a long window for the post masking (heck,
even 8192 would work). Need to experiment.

> 
> > The sin(sin) thing still? Weird function. But no sin window. OK.
> 
> Effective function.  Good energy compaction, low leakage :-)

I'll analyze its aliasing features :-)

Still, I need to know the forward/backward mdct definitions...

Ciao,

Segher

> 
> Monty
> 
> 
> 
> 
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