Filter Bank design for audio application

> Can anyone please send me the MATLAB code of a 32 channel filter bank of
> entire bandwidth range of ( 0 - 22050)Hz normally employed in audio
> codec such as MPEG-1. If you can send a non uniform filter
> bank structure of say a 25 or 27 band, correspondingly matching the
> critical bands of human auditory spectra, it would be more helpful.
> 
> Thanking you in anticipation
> 
> Yours faithfully,
> SANJAY .S