i can't see a real trend in shape and size of the white blocks. seems funny that they appear about 2/5ths into the image and dissapeare about 4/5's. it's like someone was trying to put some kind of code in it, but failed. the blocks are not solid white. (imperfections due to compression) so it won't have anything to do with coding based on color.

the only other thing i could think of is an overlay. you take 2 sheets of paper, one like a book lots of text, anotehr with holes in it that lays over the other sheet to highlight certain letters and give you a sentance, but i don't see any other sheets. and some of the blocks are so small you'de only have i's and l's for a good portion of text.

can't see too much else with it.