My Google Map Blog

In last week’s post about the Ground Truth Project we told you how Google Map Maker is a key component of Google’s strategy to achieve more accurate maps – and keep them accurate. When Google introduced Map Maker to the public back in 2008, it was initially only available in a small number of countries, but over the years its has been made available in more and more places. The relevant Map Maker support page lists 227 countries or locations where it is now available. Some of the few remaining countries not yet covered are: Colombia, Chile, Argentina, Ireland, Portugal, Spain, Turkey, China, Thailand, Indonesia, South Korea and Japan.

Zambia is one of those countries where the Ground Truth Project has not yet got to, so its maps depends almost entirely on Map Maker. I was recently asked by my sister, who lives in Livingstone, Zambia, if I would update some street names in Google Earth. The streets are in a fairly new development, and the local council has recently put up some street signs, so she wrote down the names of some of the streets and sent them to me.

When I first used Google Map Maker, every edit had to be reviewed by someone else before it went live, but over time, I have been allowed to make some changes without them waiting for review. So when I added street names to roads that were unnamed, the changes were reflected in Google Maps immediately. However, a few of the roads were not in Google Maps, so I had to add the roads as well as name them and this had to be reviewed, which took about a week. As you can see below there are still a lot more streets without names, so perhaps next time I am in Livingstone I will go around and collect the names of all unlabeled streets that do have street signs, or perhaps I will ask the local City Council if they can give me an official map.

One interesting thing I have noticed though is that although the streets show in Google Maps immediately, they cannot be found when doing a search. Other streets nearby do show up in search results, including ones that I have personally added the names for in the past. I am guessing that it takes a while for new additions to get into the search database.

If one of our readers is a Map Maker aficionado, maybe they can let us know if this is a correct guess, and if so, how long it typically takes to for names to get into search.

It used to be the case that changes made in Map Maker would eventually filter through to Google Earth. However, I corrected the name of a major road (Airport Road) in that area in January of this year and it still shows the old name in Google Earth (Libala Drive). However if you search for ‘Airport Road’ in Google Earth, it finds the correct road.

The post Mapping with Google Map Maker appeared first on Google Earth Blog.

We told you earlier in the week how the Google Maps data is not always 100% accurate. Google does, however, put in an extraordinary amount effort into making it the best it can be.

Google originally depended largely on external data providers for its maps information. But that changed in 2008 when project Ground Truth was founded. The Ground Truth project involves getting data from authoritative sources such as governments, postal services and map providers, which is then overlayed on satellite imagery and updated to make it more accurate. Google then uses satellite imagery and Street View imagery to add a lot more data to the map. It uses a variety of processes including a lot of manual editing by highly trained map editors, as well as a number of algorithmic methods, such as using computer vision to go through Street View imagery and pick out street signs, street names, business logos and more. Finally, they get feed back from users via the ‘Report a problem’ feature, or Google Map Maker.

It is important to realize that there is a lot more to maps than what you see directly in Google Maps. Google Maps also contains a lot of hidden information such as road rules, including speed limits, one way streets, traffic lights, stop/yield signs and no turn signs. These are used by Google maps when providing directions.

Google Maps contains a lot more than just street names.

The Ground Truth project is not yet used for the whole world, but they have been expanding rapidly. Ground Truth recently announced their 50th country. For the remaining countries they use a combination of external data providers and Google Map Maker.

For a more in depth look at the Ground Truth project watch this excellent presentation from Google I/O 2013 and read a four part series on the making of maps on the Google Lat Long Blog. (Part 1, Part 2, Part 3, Part 4)

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