Google has begun scanning the streets of Paris, gathering data for its Street View service, which adds street-level photography to the satellite views offered by Google Maps. The search company will gather a wealth of data from the project but, thanks to France's strict privacy  laws, it may also pick up a few lawsuits on the way if it chooses to publish the photos unedited.

Two Google employees were spotted on the Western outskirts of Paris on Friday as they mounted a sophisticated array of cameras and laser scanners on the roof rack of their black Opel Astra. The equipment was connected to a Dell computer visible inside the car. Although the vehicle was unmarked, the driver and passenger said they worked for Google.

Similar vehicles, some of them bearing the Google Street View logo, have been spotted in other European cities in recent weeks, indicating that Google is gathering data on a massive scale in preparation for the launch of the service in Europe.

But as the company offers global access to its most popular services, it will also have to think about local legislation and culture.

The sun is out in Paris and the streets in front of the capital's cafés are already packed with Parisians, so Google's cars are bound to catch a few of them on camera. Yet in France, citizens have a "droit à l'image," the right to their own image: pictures identifying them as they go about their private business may not be published without their permission. That could put the brakes on Google's deployment of Street View in France, unless the camera-cars are accompanied by an army of clipboard-wielding legal assistants asking bystanders to sign release forms as they sip their coffee.

So far, Google plans to hold back in Europe, launching the service only when it has worked out how to do so while respecting local laws, a company official recently told IDG News Service. Among the technical solutions it is considering are blurring faces in images, which would require an enormous amount of image processing, or only publishing unidentifiable low-resolution images, which would severely limit the interest and usefulness of the service.

In the U.S., Google's use of Street View imagery has already brought it a few lawsuits since its launch in May last year. Its approach there has been to withdraw images where someone objects to their publication -- just as it has withdrawn books scanned for its Book Search where publishers have accused the company of nonchalantly and systematically breaching their copyright. Such action after the fact sits ill with the French legal system, however, where the company will be expected to respect the law even before someone objects.

The differences between the U.S. and Europe are not just legal and cultural: they can also be architectural. The North American cities where Google began its Street View service are typically composed of wide streets laid out in an easily mapped grid pattern, but streets in the densely packed centers of Europe's historic capitals can be much more tortuous. Rue Maurice Utrillo, just by the famous church of Sacre Coeur in the North of Paris, will pose a particular challenge for Google's Street View team: from the church, the street descends abruptly in an 80-meter-long flight of steps.