Google is rolling out a feature that lets members of its online social network automatically find themselves in photos posted by friends.

The "Find My Face" feature being added to Google+ over the next several days is opt-in only, meaning people have to make a point to turn it on.

By leaving it to Google+ members to activate the feature, the Internet giant was sidestepping privacy concerns raised when social networking rival Facebook added facial recognition in an opt-out style this year.

"By turning on Find My Face, Google+ can prompt people you know to tag your face when it appears in photos," Google+ photos team engineer Matt Steiner said in a blog post.

"Of course, you have control over which tags you accept or reject," he explained. "We hope this makes tagging your photos much easier."

Google remains undaunted in its bid to create a flourishing online community that can go toe-to-toe with social networking powerhouse Facebook.

The California firm's popular products and services will increasingly be woven into its nascent but fast-growing Google+ social network to make joining irresistible, executives said at an Internet conference here in October.

"We are in an enviable position that we have people who come to Google," Vic Gundotra, vice president in charge of Google+, said at a Web 2.0 Summit in San Francisco.

"We are in this for the long haul... By Christmas you will see Google+ strategy coming together."

Google+ has attracted more than 40 million users since it opened to the public in September, but has a long way to catch up with Facebook's membership of approximately 800 million.