/sci/ - Science & Math

>>4217972
You missed some squares.

By the way, the reason it's being done in 8x8 squares has to do with the way the JPEG format works. If you tried to encode a message in scattered pixels, JPEG's lossy compression algorithm would it.

I suspect what's been done is that the DC component of each 8x8 block has had its last bit changed. In that case, the picture here, made by converting (0,0,0) to blue and (1,1,1) to red, will also be missing some of the squares, because the text obscures the effect. I'll look into it and see if this is what's been done.

>>4218900
is probably correct. If so, the problem then reduces to finding the right steganography program to extract the message. We need to look for any hints in the image as to the program used, and test the image with various programs that hide data in JPEG files (especially ones whose algorithm is similar to what I described).