How Google Maps Gets the 'Ground Truth' for Street View

A peak under the hood at "Ground Truth"—the operation behind Google Street View.

1 minute read

December 21, 2014, 5:00 AM PST

By James Brasuell @CasualBrasuell


Greg Miller details the new layers of information that the Google Maps team is extracting from its operation "Ground Truth," or "a combination of algorithms and meticulous manual labor" that collects data and applies it in the form of Google Street View.

Since Google Street View launched in 2007, the Google Maps team has discovered that the data their cars collect can be used for much more than just spot checking their Google Maps data on the ground. "Those algorithms borrow methods from computer vision and machine learning to extract features like street numbers painted on curbs, the names of businesses and other points of interest, speed limits and other traffic signs," writes Miller.

Miller was granted behind-the-scenes access to the Google Maps operation fopr the article, enabling him to share a lot of the technical details behind Google Maps. His summation after his tour: "The maps, it seems, are only getting deeper."

Monday, December 8, 2014 in Wired

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