This is a pilot project in Australia:
Individuals who have shared intimate, nude or sexual images with partners and are worried that the partner (or ex-partner) might distribute them without their consent can use Messenger to send the images to be “hashed.” This means that the company converts the image into a unique digital fingerprint that can be used to identify and block any attempts to re-upload that same image.
I’m not sure I like this. It doesn’t prevent revenge porn in general; it only prevents the same photos being uploaded to Facebook in particular. And it requires the person to send Facebook copies of all their intimate photos.
Facebook will store these images for a short period of time before deleting them to ensure it is enforcing the policy correctly, the company said.
At least there’s that.
EDITED TO ADD: It’s getting worse:
According to a Facebook spokesperson, Facebook workers will have to review full, uncensored versions of nude images first, volunteered by the user, to determine if malicious posts by other users qualify as revenge porn.