Perceptual image search 作者： Martin Saturka

Search by images, including by altered forms of the images, can help in assessing of the images. The question here is: had anyone posted a form of the image? And the "Perceptual image analysis" extension can help to find out since when the images are online then.

* search by images even from private sites
* open-source tools for journalists
* part of perceptual image suite