The Russian spy scandal that’s been making headlines this week has briefly crossed over into the realm of technology with news that the accused spies hid secret messages and data inside the code of seemingly-ordinary digital photos–the above picture apparently “has the map of an airport hidden in its data,” according to Tech News Daily.
While hiding stuff in image files isn’t exactly a new phenomenon, the method used in the Russian spy case is apparently a bit more than simply merging text and images together. Instead, the alleged spies altered the numeric codes of certain colors found in the pictures to reflect hidden messages that wouldn’t be noticed simply by looking at a particular photo.
According to Tech News Daily:
“To generate the picture on a computer screen, the computer assigns every pixel three numeric values that correspond to the amount of red, green or blue in the color the pixel displays. By changing those values ever so slightly, the spies could hide the 1’s and 0’s of computer language in the picture’s pixel numbers, but without altering the picture’s appearance to the human eye.”
Sine the 90s, this steganographic trick has been presented as a theoretical means of conveying hidden messages, although the FBI has apparently not publicly acknowledged any actual cases of it until now.
Columbia University computer science professor Steven Bellovin told Tech News Daily, “There have been occasional claims in the press about al Qaeda using it, but never with any evidence or even attributed to specific government officials. Here, we have court papers filed by the FBI under penalty of perjury that says these folks were doing it. The threat, in other words, is no longer hypothetical.”
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