Google will extend its Street View mapping service into Germany by the end of the year, but data protection officials said they were surprised by the fast-approaching deadline for residents to object to having their homes appear via Street View.

Street View, which takes 360-degree photographs from cameras attached to Google-owned vehicles, will be available in 20 German cities by year's end, including Munich, Berlin, Hamburg, Nuremburg, and Düsseldorf, Google announced in a blog post.

Starting next week, Google will kick off a one-month period, during which Germans will have the option to opt-out of having their house or apartment appear on Street View. Those who don't want their homes to appear have until Sept. 15 to inform Google at google.de/streetview.

Data protection officials, however, said they were caught off guard by Google's announcement. In a translated statement, John Caspar, Hamburg's commissioner for data protection and freedom of information, said he was "surprised" to learn about the imminent launch of Google's opt-out program.

Google informed him of the launch last Thursday, which does not give the commission much time to investigate the company's plans, he said. A deadline "must be carefully prepared, coordinated, and announced," Caspar said.

Complicating matters, he said, is the fact that many Germans are on vacation for the month of August. He also took issue with Google's refusal to set up a hotline for residents to call and ask specific questions about Street View.

Google, however, said an initial deadline for objections is necessary to facilitate a complex process. Anyone who objects after the fact can request to have an image of their home pulled from the site.

"Processing these requests and applying blurring is a complex task which takes time," a Google spokeswoman said in an e-mail. "So we need to receive all requests by September 15 to allow time to process, verify and then apply the blurring, before we make Street View available in Germany."

"Of course people will still be able to use the 'report a problem' button directly in the Street View image once the product is launched, just as they can everywhere else where the product is available," she concluded.

Google's Street View made headlines earlier this year when it was revealed that Wi-Fi data collection devices attached to the vehicles had accidentally collected data traveling over unencrypted networks. In June, Google said it would turn over that Wi-Fi data to German, French and Spanish data protection authorities.