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

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Get top-rated, practical training

Bird's eye view of manufactured home park.

Manufactured Crisis: Losing the Nation’s Largest Source of Unsubsidized Affordable Housing

Manufactured housing communities have long been an affordable housing option for millions of people living in the U.S., but that affordability is disappearing rapidly. How did we get here?

March 25, 2025 - Shelterforce

U-Haul truck on road with blurred grassy roadside in background.

Americans May Be Stuck — But Why?

Americans are moving a lot less than they once did, and that is a problem. While Yoni Applebaum, in his highly-publicized article Stuck, gets the reasons badly wrong, it's still important to ask: why are we moving so much less than before?

March 27, 2025 - Alan Mallach

Rusty abandoned oil well and equipment with prickly pear cactus next to it in West Texas.

Using Old Oil and Gas Wells for Green Energy Storage

Penn State researchers have found that repurposing abandoned oil and gas wells for geothermal-assisted compressed-air energy storage can boost efficiency, reduce environmental risks, and support clean energy and job transitions.

March 31, 2025 - Pennsylvania State University

Downtown Los Angeles skyline viewed from a distance with freeway and trees in foreground.

Updating LA’s Tree Rules Could Bring More Shade to Underserved Neighborhoods

A new USC study finds that relaxing Los Angeles’ outdated tree planting guidelines could significantly expand urban tree canopy and reduce shade disparities in lower-income neighborhoods, though infrastructure investments are also needed.

4 hours ago - USC Dornsife

Aerial view of Claifornia aqueduct with green orchard on one side.

California's Canal Solar Projects Aim to Conserve Resources and Expand Clean Energy

California’s Project Nexus has begun generating electricity from solar panels installed over irrigation canals, with researchers and state agencies exploring statewide expansion to conserve water and boost clean energy production.

5 hours ago - Turlock Journal

Close-up of older woman's hands resting on white modern heating radiator mounted on wall indoors.

HHS Staff Cuts Gut Energy Assistance Program

The full staff of a federal program that distributes heating and cooling assistance for low-income families was laid off, jeopardizing the program’s operations.

6 hours ago - The New York Times