Un-blurring mosaic-blurred images

By at 7:33 am Sunday, Jan 7

Here's a research report on "unblurring" information on checks and credit-cards that has been scrambled with the Photoshop "mosaic" effect -- this guy claims that he can extract the hidden numbers.
What does this mean? Well, let's take the mozaic version of 0000001 (zoomed in): ... and identify the brightness level (0-255) of each mozaic region, indexing them in some consistent fashion as a=[a_1,a_2...,a_n]: In this case, the account number 0000001 creates mozaic brightness vector a(0000001)=[213,201,190,...]. We find the mozaic brightness vector for every account number in a similar fashing using a script to blur each image and read off the brightnesses. Let a(x) be the function of the account number x. a(x)_i denotes the ith vector value of the mozaic brightness vector a obtained from account number x. Above, a(0000001)_1 = 213. We now do the same for the original check image we found online or wherever, obtaining a vector we hereby call z=[z_1,z_2,...z_n]
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