A million child abuse images were digitally fingerprinted.
According to the Internet Watch Foundation, digital fingerprints of a million images of child sexual abuse have been created.
The fingerprints, known as hashes, will help companies and police find copies of the images, according to the UK charity in charge of finding and removing such material online.
It is hoped that by doing so, the images will not be reused.
The photographs come from the government’s Child Abuse Image Database.
The database contains some of the most extreme online content, known as category A and B material.
Hashes are identifying codes generated by an algorithm that serve as a fingerprint for each image or video.
Many technology companies use hash lists to search for child abuse material on their systems, comparing hashes of images to lists created by organizations such as the IWF.
However, the system has limitations. Changes to images can change the hash value, allowing an image to evade detection – though the IWF insists that the technology it employs allows an image to be resized, cropped, or have its colours changed without changing the hash.
