[vorbis-dev] Optimisations

[Jason Hecker]

>Actually, *adding* many small numbers to a large number is what endangers 
>you most in floating point, while multiplication, in general, preserves 
>your significant digits very well.

Ah, yes, good point.  Now my blood sugar is up (post lunch and coffee), I 
see my multiplication argument is fatally flawed.  Yes, I think this is 
what I was meant to be saying... <cough> adding big numbers and small 
numbers is a source for grief, not multiplying them.

>In fact, floating point multiplication accuracy is independent of the 
>relative order of magnitude of the operands (except in limit cases). This 
>is one of the advantages of floating point over fixed point (not to say 
>fixed point is never appropriate).

Still, has any analysis been given to the required precision and dynamic 
range of the numbers used within, rather than assuming floats would be 
doing the right thing all the time?  If you use integer (fixed point) maths 
you can have very good control over the precision and efficiency of 
arithmetic operations.  Are artifacts that various other MP3 encoders 
suffer from the result of poor maths and precision accounting?

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