The maps were created by using artificial intelligence techniques to recognise human-built structures
Facebook said it is set to release to the general public highly detailed maps of world population data that it says could be used in development and disaster relief efforts.
The maps, created by using artificial intelligence techniques to recognise human-built structures in DigitalGlobe high-resolution map images, are cross-referenced to census data and have a resolution of five metres, several degrees of magnitude finer than previous efforts – the World Bank’s WorldPop project, for instance, offers a resolution of 100 metres.
Network infrastructure deployment
Facebook said the maps are intended to help it deploy drones and other Internet connectivity technologies in remote areas as part of its Internet.org programme.
“Defining the specifications of the technologies that we are developing first requires accurate information of how people are aggregated in these areas,” Facebook stated.
The data currently covers 20 countries and 21.6 million square kilometres, including India, Mexico, Sri Lanka, Nigeria and other African nations, for a total of about 350TB of data, based on 14.6 billion map images, Facebook said.
To carry out such a massive effort the company said it took a three-step approach, first using conventional image-processing to discard vast bodies of desert, forest and water. Then it applied a neural network to identify whether a particular image segment contained a building, and finally a second, specialised and human-supervised neural network to identify outlines of buildings and highlight those which it had high confidence represented human-inhabited structures.
“Typically, neural networks need to be trained on large volumes of images to obtain sufficient accuracy,” Facebook stated. “Using the above approach, we were able to train our model by adding only about 8,000 binary labeled satellite images from within one country.”
The company said it is working with Columbia University, which maintains a project called Gridded Population of the World (GPW) that collates existing data, to release the data to the public later this year.
Facebook first spoke of its mapping efforts last year during a briefing about its Aquila Internet-access drones, which it plans to begin flight-testing this year.
The mapping project isn’t without its critics, with an associate fellow at think tank Chatham House telling the BBC that it “takes knowing your customers to stalker-like levels”.
Google’s parent company Alphabet is also testing various Internet-access efforts, including drones and high-altitude balloons, which are due to begin trials this year in Sri Lanka.
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