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
A replacement for blur could just be black boxes. Seems easy and safe enough.

>>_bxg1+9K
Make sure they are 100% opacity. A lot of people mess this up and use 90% opacity or similar and the original image can be revealed by messing with the color levels.

>>Polyla+u21
I've doxxed my Reddit username on my Apple phone doing that exact thing. The black marker is not opaque, even after a few stripes over the username. You have to do it many more times.

>>t-writ+K91
Easier to select an area and delete it from the layer entirely so that a transparent hole is left. Then make sure you cleanup EXIF and other metadata or you may have the original image still in a thumbnail field at reduced fidelity.

Free online metadata viewer http://exif.regex.info

Powered by FOSS (Perl-based) https://exiftool.org

>>aspenm+4d1
Do not keep it transparent! The Gimp for example keeps the underlying colour data, and just sets the opacity to 0.

this bug (closed as Expected Behavior) has a demonstration: https://gitlab.gnome.org/GNOME/gimp/-/issues/4487

>>girst+pk1
It blows my mind that there are so many ways to screw up something this simple.

Edit: to be clear I meant this as a commentary on the technology, not the people making the mistakes

>>_bxg1+fq1
I think there is a need for a dedicated image privacy offline program. On a technical level its very easy to preserve privacy, its just the tools people are using were built for other purposes (Non destructive editing is highly desirable in normal cases).

All the program has to do is scrub all exif data, have a censor box/brush that is 100% black and rencode the image so there is no remaining unneeded data.