Reordering question

Hi!

MAD for sp3r5m 3DSP core www.3dsp.com is ready.
In average up to 256 kb/s 27MHz is more than enough to decode any mp3
bitstream. But 320 kb/s - required calculation is very close to
available resources (and maybe even worst)

Only - I want to improve performance in some places

Now I am looking on
void III_reorder(mad_fixed_t xr[576], struct channel const *channel, unsigned char const sfbwidth[39])

C implementation takes ~30 000 cycles - it is too much. So could you
tell me can I use for reordering this one simple scheme

for sb=0 to 31 do //For all 32 subbands
   for window=0 to 2 do //For each of the 3 windows
       for ws=0 to 5 do //For each sample within a window
            Xro[18*sb + ss] = Xdis[18*sb + window + 3*ws] //Reorder
       end for
   end for
end for
  
If answer is "no" - so could you explain the role of
unsigned char const sfbwidth[39]
in original MAD reordering function
very shortly of course.

Thanks for answers


-- 
Best regards,
 Grigory                          mailto:[email protected]