The article mentions a (now failed) technique that generates signatures for each message and ignores any future messages that have the same sig. That technique can now be circumnavigated by adding random specks, dots and lines to subtly change the image. What would be interesting to try as a filter is the Fourier transform. A 2D FT of these spam images would generate the same signature despite any randomization. That would allow for the generation of signatures unique to a group of very similar spam messages that used images. Whats also interesting is that the FT of an image with the word "Viagra" would generate a FT signature comparable to one that had "viagra" "vi*gra" in any orientation, color or weird background image.
Slashdot Mirror
The subject says it all.
After the recent request to fund the Iraq war to the tune of $245 billion, it really puts our priorities in perspective.
The article mentions a (now failed) technique that generates signatures for each message and ignores any future messages that have the same sig. That technique can now be circumnavigated by adding random specks, dots and lines to subtly change the image. What would be interesting to try as a filter is the Fourier transform. A 2D FT of these spam images would generate the same signature despite any randomization. That would allow for the generation of signatures unique to a group of very similar spam messages that used images. Whats also interesting is that the FT of an image with the word "Viagra" would generate a FT signature comparable to one that had "viagra" "vi*gra" in any orientation, color or weird background image.