By Maggie Shiels
BBC News, San Francisco
The technology is a by-product of anti-piracy software
Google engineers have adapted a software program to help track child sex predators and search for patterns in images of abuse on the web.
Google has created the technology for the National Centre for Missing and Exploited Children (NCMEC).
It was originally developed to block copyrighted videos on the company's YouTube division.
The program uses pattern recognition to enable analysts to sort and identify files containing child sex abuse.
Google says its aim in teaming up with the centre's Technology Coalition Against Child Pornography is to develop solutions that would make it harder for people to use the web to exploit children or traffic in child pornography.
"You always hope that your work will eventually be used to do some good in the world, and this was an amazing chance to make that hope real," said Google research scientist Shumeet Baluja.
Mr Baluja, who was also the technical leader of the project, said that as more and more predators use the web to ensnare children, "analysts were getting overwhelmed by all of the data they had to sift through".
Since 2002 the NCMEC has pored over 13 million child sex abuse images and videos in an effort to help police identify and rescue children from harm.
In the last year they have looked at five million pictures.
Google says the new tools will enable the centre's analysts to search their systems more quickly and easily as they try to sort and identify files that contain images of child sex abuse victims.
"The program uses pattern recognition and will work even if the pattern has been modified," explained technology analyst Larry Magid.
"So if police can identify a pattern such as a calendar on the wall or a t-shirt logo, they have a much better chance of finding the exploited child and catching the suspect."
The technology is an outgrowth of the anti-piracy software Google developed to helps its YouTube division ferret out videos of suspected of being posted without the agreement of copyright holders.
"Criminals are using cutting edge technology to commit their crimes of child sexual exploitation, and in fighting to solve those crimes and keep children safe, we must do the same," said NCMEC President and CEO Ernie Allen.
Google engineers and scientists were able to work on the project on what the company calls "20% time", which allows all employees to dedicate that amount of time to projects they initiate.
Some of those projects benefit stockholders or end users, but in this case the benefit could be to thousands of children.