How Google identifies house numbers in Street View

As much as I love Google Earth, I use Google Maps at least as often due to the amazing GPS navigation that it provides in my car.  Part of that is due to their work in Street View over the years and the data (and imagery) that it collects.  Part of what they’ve developed is a system for automatically reading house numbers, and it’s an amazing system.


MIT Technology Review has a great overview of how the system works, including some great tid bits such as this:

…they assume that the building number has already been spotted and the image cropped so that the number is at least one-third the width of the resulting frame. They also assume that the number is no more than five digits long, a reasonable assumption in most parts of the world.

But the team does not divide the number into single digits, as many other groups have done. Their approach is to localize the entire number within the cropped image and to identify it in one go—all with a single neural network.

It’s quite a fascinating read and I encourage you to check it out.  Google has pushed harder and taken Street View further than anyone imagined they would, and it’s exciting to think about where it might be in a few more years.

About Mickey Mellen

Mickey has been using Google Earth since it was released in 2005, and has created a variety of geo-related sites including Google Earth Hacks. He runs a web design firm in Marietta, GA, where he lives with his wife and two kids.


  1. Clever technology, but it could never provide a complete set of addresses even with ‘interpolation’ (buildings out of sight of Street View, without visible numbers, and so on) and hence a complete navigation system. It is not clear whether Google incorporate comprehensive address gazetteers from third parties where available to improve navigation. Google also appear not to release their database of addresses to allow independent verification and/or licensed third party use.

  2. Corky McButterpants says:

    They appear to show up on the ʀᴇCAPTCHA™ verification widget.
    But I always enter garbage anyway; not like we’re getting paid to have our posting inconvenienced…

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