US Internet giant Google launched on Tuesday a charm offensive for its "Street View" navigation service, aiming to soothe the privacy doubts of a sceptical German public.

Attending the CeBIT high-tech fair, the world's biggest, for the first time, Google showcased three of their "Street View" cars -- sleek, black Opels with eight mounted cameras to take pictures of streets, buildings and cities.

The software, based on photographs which create 3-D imagery, allows surfers to "walk" through the streets of cities such as New York, Paris or Hong Kong.

Launched in the United States in 2007, it is already available in several European countries, including France and Britain, but it has come under attack from privacy campaigners, concerned about being snapped without their consent.

Germany, where Google intends to launch the technology this year, is especially sensitive to the issue after abuses of privacy by the Nazis and the Stasi secret police of the old East German communist regime.

"We strongly believe that Google Street View is completely legal in Germany," Kay Oberbeck, a spokesman for the firm's local unit, told a packed news conference.

The "Street View" programme already automatically blurs faces and car registration plates. However, as a concession to privacy concerns in Germany, the company will also allow unhappy users to delete a disputed photo.

Michael Jones, the firm's "chief technology advocate", said the software should be viewed as an educational and fun tool.

"You see the world as you would see it if you were really there."

"Google is not an invader of countries. It's not some super spy camera. It's just a camera mounted on a car. It's not super high quality photography," added Jones.

Nevertheless, he stressed: "Now we've heard a bit about the concerns, we're going to change things.

"We don't think like we're in a battle with the privacy people. We don't agree with everything they say, but we're learning."

Lena Wagner, another Google spokeswoman, said that the firm had been slow to win people over.

"We should have communicated earlier on Google 'Street View', I admit. We started taking photos in Germany in 2008 and we should have explained things more clearly to people," she said.

"The idea of 'Street View' is not to take private pictures. We take photos like any other tourist would," added Wagner.

However, the service has already raised some concerns outside Germany.

Police in Raahe, northern Finland, last month began an investigation at the request of a man whose picture could been seen online on "Street View."