"We're taking this opportunity to test our new face-blurring technology on the busy streets of Manhattan," wrote Google software engineer Andrea Frome, in a company blog posting. "This effort has been a year in the making -- working at Street View-scale is a tough challenge that required us to advance state-of-the-art automatic face detection, and we continue working hard to improve it as we roll it out for our existing and future imagery."

Street View allows users to pan, rotate and zoom-in while taking street level photographs in 30 cities, including those in N.Y.C., San Francisco, Miami and Chicago. While the software was designed to take harmless pictures of landmarks, points of interest, shops and parks, some nefarious images have shown up, including photos of women's underwear, public urination and porn shop patrons.

Google's Blurring Software

Under U.S. law, Google does not need permission from the people caught in its photos, although some may not be even aware of their captured image. If users do complain, Google said it will remove photographs. However, privacy laws abroad are, in most cases, much more restrictive.

While not yet launched in Europe, Google has hit the streets of major cities in Canada, Australia as well as cities such as Rome and Paris. Cars emblazoned with the Google logo and roof-mounted cameras have been spotted on streets snapping pictures. Google has said it expects to officially launch Street View overseas sometime next year.

"One of the reasons that Google has implemented this technology now is possibly that the privacy laws in Canada, Australia and much of Europe would not have allowed images like these to be published otherwise," wrote Google employee "James" in a blog.

On Thursday, Peter Hustinx, Europe's data protection supervisor, spoke about observing privacy rules overseas.

"Making pictures everywhere is certainly going to create some problems," European Union Data Protection Supervisor Peter Hustinx told a news conference to present his annual report, according to Reuters.

Google admitted that it has some wrinkles to iron out in implementing the face- blurring technology.

"Due to the vast amount of data involved here, the system is fully automatic--and appears to be prone to making mistakes," wrote James. "It seems that the system really is very good though."