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Faster file I/0



I work with satellite images, often they are on the order of 1024x1024 pixels.
MACL is a wonderful environment for developing new pattern recognition 
techniques for use in image analysis but it is so S-L-O-W for reading or
writing these large images (I generally store them as a sequence of bytes
and I need to have them as matrices when I work with them).  I found a file,
fast-file-io.lisp, on one of the machines that archives contributed lisp code
and it has speeded things up considerably.  I used to be able to walk across
the street, have coffee, breakfast and read the paper while reading in an
image, now I just have time for the coffee.  I'm sure the I/O speed can be
improved, Image 1.31 (and other graphics/image analysis programs) can,
in 5 seconds, read in what it takes me 5 minutes to write out from MACL.

I've been programming in LISP for a number of years but I'm fairly new to
the Mac.  Any suggestions/code on speeding up I/O would be greatly 
appreciated.


Jeff Banfield
Dept. of Math Sciences
Montana (it's 30 below zero this morning) State University
(406) 994-5367
umsfjban@deimos.oscs.montana.edu