In this long but useful presentation from 2012 Google Maps vice president Brian McClendon and colleages provide a detailed overview of the platforms evolution. Some of the key points are summarised below.
In the mid 90s Silicon Graphics developed the ‘Space-to-Your-Face’ demo to demonstrate the power of their Onyx Infinite Reality CGI workstation. In the demo the view zooms from orbit to the Matterhorn via Lake Geneva, using a combination of satellite, aerial imagery and terrain data. This is included in the Silicon Graphics showreel from 1996 which be viewed on YouTube here.
In 2001 the company Keyhole was founded as a startup providing mapping for the travel and real estate industries on the basis of a subscription model. After achieving wider recognition through use by CNN during the invasion of Iraq in 2003, the company was subsequently acquired by Google in 2004.
At the same time Google were working on the creation of Google Maps which used a combination of client side processing via AJAX and pre-rendered map tiles to enable its highly interactive and smooth scrolling slippy map system. However, now that network bandwidth and processing power has been increased Google Map tiles are no longer pre-rendered and are instead provided on demand.
Between 2005 and 2008 Google Maps licensed further data to obtain a full world map with more comprehensive coverage. At the same time Google were also working to acquire high resolution imagery.
Street View started in five US cities in 2007 but had expanded to 3000 cities in 39 countries by 2012. In 2008 Google released Map Maker to capture data where other basic mapping data and Street View were absent.
Google’s Ground Truth project now enables them to generate their own maps from raw data by combining satellite and aerial imagery with road data and information capture via Street View. This data is processed with an application callled ‘Atlas’ that Google developed internally. With the aid of advanced computer vision techniques they are able to detect and correct errors and extract further contextual information from the raw imagery data that helps them make their maps more complete and accurate. This includes details as specific as the names of streets and businesses appearing on signs.
Corrections are also crowd-sourced from users with the aid of their ‘Report Maps Issue’ feature. Staff at Google are then able to verify the issue with Street View, edit the map and publish the corrections within minutes.
The presentation moves on to further discussions on ‘Google Maps For Good’ and their work with NGOs (19:20), ‘Google Maps for Mobile’ and the provision of offline map availability (27:35), the evolution of the equipment used to capture Street View (31:30), and finally the evolution of their 3D technology (37:40). The final discussion in particular reiterates the content in my post yesterday from a slightly different perspective.
What I found particularly interesting in this video was the continued manual intervention via Atlas but also the extent to which they are able to gather contextual information from Street View imagery.