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From visiting famous landmarks from your sofa, to looking for strange sites, Google's Street View has many uses.

Now scientists have used photos of streets in U.S. cities to make maps showing the safety of New York, Chicago, Detroit and Boston - based on how people rated photos on a website.

The Place Pulse project works out which areas of a city are seen as rich and safe, family-friendly or dangerous, according to how people react to Street View images. 

Scientists have used photos of streets in U.S. cities to make maps showing the safety of New York, Chicago, Detroit and Boston, based on how people rated photos on the website. Click on the interactive maps above to see streets that are perceived to be safe (marked in green) and less desirable addresses (in red)

Scientists at Massachusetts Institute of Technology (MIT) created the survey to let people choose between two streets, to indicate which they believe to be safer.

They then used the information, and collected the safety rankings for 3,000 images from New York and Boston, to generate an algorithm that automatically creates a safety rating for the images.

This is based upon features such as colours and shapes.

The experts use the algorithm to predict the safety score of any image on Street View, based on the outcome of its Place Pulse survey.

The researchers have now released four maps to show the perceived dangerous and safe areas of New York, Detroit, Boston and Chicago.

Scientists at MIT created the survey to let people choose between two streets, to indicate which they believe to be safer. From the initial results they made an algorithm create a safety score of a neighbourhood - zero being the lowest to denote a dangerous street and 10 the highest - and predict its safety

Green areas of the map represent areas, which were given a high perceived safety rating using the algorithm, while red areas show locations that are perceived as dangerous.

The map of New York City contains more than 300,000 data points of perceived safety.

The scientists developed their algorithm because to make such a detailed map without it would have required more than two million comparisons of images.

By using StreetScore they could create the maps using less than 3,000 images – or 24,000 comparisons – in the dataset.

The new tool allows experts to look at urban environments in a new way, and in the future, MIT will use it to study improvements and decay in cities. 

'We can use StreetScore to explore the determinants of urban perception, including both the local features that affect people's perception of a street view, such as the quality of buildings...the local context of a neighbourhood…such as its proximity to a highway…and the historical, economic and demographic forces that shape a city, such as architectural movements…and social segregation,' they explained.

The map of New York City (pictured) contains more than 300,000 data points of perceived safety.The scientists developed their algorithm because, to make such a detailed map without it, would have required more than two million comparisons of images

Place Pulse 2.0 is now underway, and the new survey is collecting data on 100,000 street views from 56 different cities, including Washington D.C, Sydney and London.

As well as choosing roads that look the safest, survey participants can also choose views based on which look livelier, wealthier, most beautiful, boring or depressing.

Based on the results so far, London, Paris and New York have been voted the liveliest cities according to the Street View photos.

Atlanta is currently ranked the most beautiful of cities, and Rio de Janeiro the most depressing - although the World Cup Festivities have not been taken into account.

Place Pulse 2.0 is now underway and is collecting data on 100,000 street views from 56 different cities, including Washington D.C, Sydney and London. This screenshot shows a choice of roads where users are encouraged to click on the one that looks safest. Washington DC is currently in the lead when it comes to the safest-looking streets