Ok, I used that to determine the intensity of a single pixel in greyscale. However, when I tried a simple test of it, I got unexpected results.
I made a test image, that was 24 pixels wide by 12 pixels tall. This is a jpeg that I made in kolourpaint and set to greyscale. It has a white background and I used only black color on it. I made two boxes on this image, which are each 8x with 2 white pixels all the way around and 4 white pixels in the center between the two boxes.
The truly curious can see this da vinci - quality 834 byte jpeg at this site
However, when I analyze this file, I get varied results for what should not be varied intensities. Specifically, the spots (5,5) and (5,17) should both be intensity 0 (since they are 100% black). However, this is not the case. Instead, (5,5) registers 15 and (5,17) registers 0.
Any insight as to why this is would be great!

In reply to Re^5: Perl Image Analysis by lparsons42
in thread Perl Image Analysis by Anonymous Monk

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