Can you also crack the code picture?The decoding tool the big shot built was too violent

2022-05-08 0 By

A recent post by Dan Petro, the head of a foreign technology company, has caused quite a stir in the foreign programmer community.And this post should be closely related to all of you. In his post, he warned netizens that pixelation is a very bad and unsafe method to code pictures.The information you encode can easily be repaired and your privacy compromised.The main reason is that he created a gadget for cracking pixel coding and uploaded it to GitHub as open source software.The gadget, which everyone can download for free, is used to decipher blurred images on the Internet.I know that when you see this kind of action, you should immediately go to GitHub, download this tool, and pull out your precious learning materials.Unfortunately, it’s not for removing still image mosaics.The current technology to remove the Mosaic on the picture is to simulate and compare the similar content in the database through AI, and then piece together the law of pixel movement to simulate and restore.That is, let the AI “draw”, then compress back to the Mosaic state and compare with the original, and finally bring out the similar version.But Dan developed this tool, mainly used to decipher the Mosaic typed in English letters, and the success rate is very high.And Dan also explained in detail in his post that he developed the principle of this Unredacter decoding tool.In fact, the process of cracking the Mosaic is not so mysterious as bad friends imagine.If you open a coding tool at random and blur the following string of English, you will probably get such an extremely common “low definition coding picture”.As you type, the algorithm divides the image into color blocks of a fixed pixel size, and then “smudges” each pixel block.Let a clear picture, into a lot of different shades of black, white and gray blocks.Take the image below for example: If you were to code the image below, the algorithm would divide the image into squares of 8×8 pixels, then evenly color all the pixels in the squares and paint them in different shades of gray.Although the code is typed, this conventional method still leaves enough clues on the encoded image to decipher the information.Because the Mosaic code algorithm, is fixed so two steps: first split the picture, and then use an average “daub” each square.So theoretically, as long as we understand the simple and crude logic of the algorithm, we can work backwards to decipher the image of the code.As long as you determine the size of each square, and then compare all the characters on the keyboard before and after the code effect, you can find that character.Let’s take a look at the effect of this powerful decoding tool: in fact, before Dan developed Unredacter decoding tool, there were such logical decoding tools on the market for a long time, but due to some technical problems, the accuracy of these decoding tools is not high.For example, there are character overflow problems: during decoding, there is no guarantee that text characters will be exactly 1:1 aligned with these pixel blocks, such as the awkward situation where the characters get stuck between two squares.And this also caused a lot of confusion to the decoding work.There is also the problem of inconsistent fonts, although the letters on the computer look the same to the naked eye, but because of the different rendering engines, the letters on the computer screen will be slightly different.The above two fonts are generated by two different rendering engines, and they have small differences in character length that have a ripple effect during the coding process.But if you try to decode them, they can cause a lot of trouble.There are many similar technical problems.Depix, a decoding tool, does not provide a good solution in these technical details.So the effect is only so-so.I sing it…Many programmers on the Internet are skeptical about the reliability of a decoding tool designed by Depix because the letters it interprets are too vague.One programmer, Jumpsec Lab, even went so far as to challenge the entire web by Posting an encoded image that anyone who could decipher it could contact him.Seeing this challenge, Dan decided to develop a decoding tool of his own, with some technical modifications based on Depix.Dan solved all of these problems in his own Unredacter decoding tool, which he had successfully decoded from the Jumpsec Lab, and the resulting letters were very clear.It can be said that today, Mosaic coding is extremely unreliable.Talking about so many multi-purpose Mosaic code loopholes, I believe there will be curious children to ask: so there is no more secure code?Of course there is, is directly with a big black bar, or a “holy light” to paste on it, to ensure that there will not be any redundant information leakage!These are some of the arguments and techniques Dan shared in his own post about the insafety of mosaics. Anyway, after watching the world super was shocked.We’ve been using Mosaic technology for years.The development of Internet technology, in fact, are largely rely on: the emergence of new technology, and then crack technology.This endless offensive and defensive confrontation.There are more and more ways to decipher mosaics, too, and who knows if one day the mosaics blurred into still images might be removed?I hope you can be more careful when you code your pictures to prevent unnecessary trouble caused by privacy disclosure.Writing: the florets editor: line images and information sources: Never, (, (Use Pixelation for Redacting Texthttps://github.com/bishopfox/unredacter Google image the original title:”Dozen code picture also can crack? This big guy does the decoding tool is too violent!”