TinEye, a new image search engine that specializes in image identification and comparison, on Monday entered open beta testing.

Developed by Idee, a Toronto, Canada-based imaging technology company, TinEye allows users to submit an image and find copies or derivative images online. Idee provides a similar service called PixID that offers automated image monitoring for print and online publishers.

Leila Boujnane, CEO of Idee, said that TinEye has developed a following of enthusiasts among professional creators of visual content and online designers. "Most people who actually hold a copyright to an image would like to make sure that the image is used within the copyright requirements," she said.

Some users want to know whether their work is being used without authorization. Others want to see whether their design work bears similarities to someone else's design work, which might be either a positive or negative association.

What makes TinEye particularly compelling is that it can spot copied or derivative images that have been substantially modified.

TinEye isn't exclusively for policing commercial images. Boujnane suggested that visual artists releasing work under a Creative Commons license might use Tin Eye to make sure that any attribution requirement, for example, is observed.

Boujnane said that while she wasn't aware of any lawsuits that had resulted after visual artists discovered someone using their work without authorization, she knew of several who had contacted infringing sites and worked out settlements without litigation.

Owners of porn images, frequently copied without authorization, are out of luck, however. TinEye's Terms of Service forbid the submission of pornographic or illegal files, as well as the use of automated scripts for bulk searches.

TinEye is free, but Boujnane expects subscription-based services, such as alerts indicating the appearance of copied images online, will be added over time to provide a revenue stream.