[FFmpeg-devel] [PATCH] IFF demuxer and 8SVX decoder

[Jai Menon]

On Thursday 27 March 2008 15:23:54 Michael Niedermayer wrote:
> On Thu, Mar 27, 2008 at 08:44:54PM +0000, Jai Menon wrote:
> > On Wednesday 26 March 2008 21:12:26 Michael Niedermayer wrote:
> > > uint8_t d = *buf++;
> > >
> > > > +        esc->fib_acc += esc->table[d & 0x0f];
> > > > +        *out_data++ = esc->fib_acc << 8;
> > > > +        esc->fib_acc += esc->table[d >> 4];
> > > > +        *out_data++ = esc->fib_acc << 8;
> > > > +    }
> > >
> > > you can do this with one subtraction and 2 shifts less
> >
> > I still don't know how i can eliminate the two shifts?
>
> change the table ...

I could change it to int16_t, and remove the 2 shifts.....but then i would 
need to clip twice before adding the table value to the accumulator......in 
which case imho we should stick to 2 shifts. 

Other changes  were made and all local tests were successfull. patch attached

Regards
Jai Menon
<realityman at gmx.net>
 

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