os x'erox (open source for os x)

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os x'erox (open source for os x)

Post by Info-Mac » October 26th, 2002, 9:00 am

Download: http://archive.info-mac.org/gst/grf/os-xerox.hqx

This is the first draft of an ongoing project. It is open source.
It is spinoff from Mike Beam's column on cocoa programming.
I have a cannon elph powershot 200 2 megapixel digital camera which
I wanted to turn into a xerox machine for my research.

To inspire this (other than I want glory to get me credibility for
a post doc in quantum optics somewhere) :
Why pay xerox?
Why pay with filesize and lose hard drive space or burn too many cd's?
Why not hyperlink derivations for all books with adobe acrobat. I
have done this in journal publications in pdf format, but not with textbook
excerpts.

I only needed black and white and that reduces the filesize cost
from color by as much as 24 times. To this end, I've invented the notion of
"convolution thresholding", thresholding a sharpening convolution of the
digital camera image. This is something like the human eye does with
lateral inhibition, that is something like a digital Laplacian. Not quite.
I am subtracting out the background and thresholding to black and white.

These convolutions can be sped up with being modularized in FFT's,
fast fourier transforms. It would take about a semester to do, as I have
done, with butterfly diagrams guiding coding. Don't see anything in the
next step frameworks to assist development time, yet... When I or someone
else gets a FFT in it it will be one lean mean xerox copying machine.

Note, not exactly 24 times reduction as above because the .JPG file
you get out of a camera is compressed whereas the tiff you throw into a pdf
file is not, not at least as I understand how to do it. There is no JPG
compression for black and white. But, sometimes I can get costs of 16k, 32k
and 50k for page that started out as a 1Meg JPG and that's more than 24
times (I use other tricks, exporting from iPhoto by rescale when resolution
not required and cropping).
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