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Faster file I/0
- To: info-macl@cambridge.apple.com
- Subject: Faster file I/0
- From: umsfjban@deimos.oscs.montana.edu (Jeff Banfield)
- Date: Wed, 2 Jan 91 08:29:08 MST
- Full-name:
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