[FFmpeg-devel] [RFC] AAC Encoder, now more optimal

Kostya kostya.shishkov
Sat Sep 6 19:15:55 CEST 2008

On Sat, Sep 06, 2008 at 06:17:38PM +0200, Michael Niedermayer wrote:
> On Sat, Sep 06, 2008 at 06:36:16PM +0300, Kostya wrote:
[choosing codebooks for coeffients encoding]
> > IMO it should encode losslessly at this stage, so no rate distortion.
> How much quality do we loose from this?

none (yet) - quantization is performed the same way for all codebooks
I still have to introduce codebook-specific quantization (and distortion from it).

> And why exactly should the RD values not be used?!
> > 
> > While this seems a bit faster it's significantly worse - on my test sample it's
> > 222809 bytes against 209792 with current code. 
> Well it was just showing how to optimize the code, its untested and not
> unsurprissing that it contains (a) bug(s).
> After all you where asking for optimization tips, not for others to do the
> optimizations.
> Does the code work if the if() is disabled by && 0 ? it should be completely
> identical to the old code without the if()

Well, current piece of code works fast and good enough to me.
But since you say it can work faster and better, I'll try to implement the needed
> [...]
> -- 
> Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
> It is dangerous to be right in matters on which the established authorities
> are wrong. -- Voltaire

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