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               Message-ID: <37235E68.253F0D57@concentric.net>
                     Date: Sun, 25 Apr 1999 14:26:48 -0400
                     From: Eric Durant <eadurant@concentric.net>
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                       To: Dines Justesen <dines@resnet.gatech.edu>
                  Subject: Re: JPEG in Matlab ?
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Dines Justesen wrote:
> I am doing a project where I need to extend the JPEG algorithm to 3
> dimensions, so what I am looking for is an M file with the 2-D code,
> which I can then modify.

I've written a set of MatLab and MEX functions which implement baseline
JPEG (and various enhancements) through the intermediate entropy coding
symbol stage.  Instead of using a Huffman code to generate a JPEG
bitstream, though, I use the symbol frequencies to make a Shannon rate
estimate.

I'm completing a paper on this, which I plan to post along with the
MatLab code to my Website this Thursday.

If you're working with 3-D spatial images, the material on quantization
matrix structures should prove helpful.  If you're working with video,
I'm curious what quantization structures you're considering for the
temporal frequency dimension of the DCT.

Eric Durant
---
Website:  http://www.edurant.com/
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