zlacker

>>dsr12+(OP)
Some tips to maximise user privacy while deploying this tool:

1) The code, for now, runs locally. This is good. To avoid the possibility of the code being tampered with at a later day (for example, it could be modified to send copies of the image to a server), download the webpage and use the saved copy, not the live copy.

2) Do not use the blur functionality. For maximum privacy, this should be removed from the app entirely. There are _a lot_ of forensic methods to reverse blur techniques.

3) Be weary of other things in the photograph that might identify someone: reflections, shadows, so on.

4) Really a subset of 2 and 3, but be aware that blocking out faces is often times not sufficient to anonymise the subject in the photo. Identifying marks like tattoos, or even something as basic as the shoes they are wearing, can be used to identify the target.

>>Ansil8+vn
"There are _a lot_ of forensic methods to reverse blur techniques"

Any examples? You can't reverse it if the data is gone.

>>Nightl+Qn
Here's a very specific example, having to do with a much smaller data-set, the OCR font used for the routing and account number on cheques.

https://lifehacker.com/how-to-uncover-blurred-information-in...

>>fragme+2u
Very minor but interesting nitpick: the font used on checks is not OCR (optical) but MICR (magnetic ink). The design objectives are different and different font families exist for the two purposes. MICR as used on checks (more properly called E-13B) bears unusual, distinctive character shapes emphasizing abnormally wide horizontal components due to the need for each character to have a distinctive waveform when read as density from left to right, essentially by a tape recorder read head. Fonts optimized for OCR are usually more normal looking to humans because they emphasize clear detection of lines instead.

E-13B is a bit of an ideal use case for this method because of the highly constrained character set used on checks and the unusually nonuniform density of E-13B. The same thing can be done on text more generally but gets significantly more difficult.