Ask HN: What camera apps exist that can blur faces securely? (re: Minneapolis)

#1

Post by mtae » Thu, May 28, 2020, 7:14 PM UTC

Are there apps that can take photos and record videos while automatically obscuring faces securely? Blurring if it's possible to make it sufficiently irreversible, blacking out otherwise.

see the discussion here for details on which methods are NOT safe: https://security.stackexchange.com/questions/129683/is-image-blurring-an-unsafe-method-to-obfuscate-information-in-images

Re: Ask HN: What camera apps exist that can blur faces securely? (re: Minneapolis)

#2

Post by pizza » Thu, May 28, 2020, 8:24 PM UTC

Blurring just leaks information unnecessarily. We should go beyond blurring. In fact we could go beyond blacking out with bounding boxes too; we could use some kind of Mask CNN to segment the boundaries of people's silhouette, and then black those out.

This is what I would imagine it would need to look like:

[video input] -> [frames]

per frame:

[frame] -> run thru a person detection segmentation nn -> output an outline mask for the frame

fill in the outline mask in the frame with eg. black

reconstitute [set of frames] -> [output video]