[FFmpeg-devel] [PATCH] G.729A (now fixed-point) decoder
Wed Mar 19 19:20:18 CET 2008
On Thu, Mar 20, 2008 at 12:10 AM, Reimar D?ffinger
<Reimar.Doeffinger at stud.uni-karlsruhe.de> wrote:
> On Wed, Mar 19, 2008 at 11:37:08PM +0600, Vladimir Voroshilov wrote:
> > On Wed, Mar 19, 2008 at 10:46 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
> > > > Reference code uses ~((~a)>>b) for negative numbers.
> > >
> > > argh, right, L_shr(a,b) == a>>b
> > > iam silly but you are as well because L_shr(-1,1)!=0
> > L_shr(-1,1) IS equal to zero and
> > L_shr(-3,1) IS equal to -2
> > in reference code.
> That doesn't make sense, you claimed reference code uses ~((~a)>>b) for
> negative numbers, for a == -1 that gives -1 and not 0.
> So one of your statements must be wrong I think.
You are right, my statement about L_shr(-1,1) was wrong.
Anyway each +/-1 difference is accumulated from frame to frame and gives
Vladimir Voroshilov mailto:voroshil at gmail.com
JID: voroshil at gmail.com, voroshil at jabber.ru
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