converting .jpg to .txt

Hi

I am having problem converting an image file with .jpg extension to text
file  .txt extension using convert command to get the rgb value for each
pixel as a text file. I am using the command

convert file.jpg file.txt (size 700 kb)

It converts the file but takes 5 min to do it, which I think is
unusually long. I have fedora core 6 and ImageMagick-6.3.8 installed. I
tried it with fedora core 8 (with the default imageMagick version) it
takes around 2.5 min.

With ImageMagick version suitable for fedora core1 it used to take only
15 sec. 

please comment...

regards
subhashis