New CCTV cameras can track pedestrians around cities

The system assigns colours and numbers to pedestrians in order to track them across different cameras. Image: University of Washington.

After two pressure cooker bombs exploded during the Boston Marathon in April 2013, killing three and injuring around 300 more, it took police five days to track down the culprits. While thousands of officers scoured a 20-block area, transport systems were shut down and residents told to stay indoors.  

Now, just over a year later, an electrical engineer from the University of Washington says he has developed technology that would have shortened that manhunt to “hours, if not minutes”. 

That engineer is Jenq-Neng Hwang, who has created a system of cameras which use algorithms to track moving objects across large areas – even when they move out of sight of one camera and into the frame of another.

Before the cameras begin tracking, they record “training footage”, to understand how objects change in angles, texture and colour when viewed from the cameras’ respective locations. Once tracking, they assign moving objects colours and numbers, and use the information from the training footage to detect people already identified by another camera.

At the moment, the cameras can’t do this in real time - the technology operates as a faster version of officers searching footage frame-by-frame for suspects. But eventually, Hwang hopes these cameras could operate around cities, on drones and in robots to track suspects or create a kind of moving Google Earth, with maps populated by cars and people. You could, for example, see the traffic on a road you’re about to travel to, or use a tracking drone to find survivors after a natural disaster.   

In the video below, Hwang admits there are “privacy issues” surrounding this vision. But to him, it seems absurd that we collect millions of hours of CCTV footage in cities, only for it to “end up on servers, never to be viewed again”.

One idea that does seem a little excessive is the use of the cameras in shops, to collect what Hwang calls “valuable information about a specific shopper’s preferences”.  While he enticingly says this information would be used to send shoppers “special coupons”, we’d probably rather shop without a robot salesman breathing down our necks.

All images: University of Washington. 

 
 
 
 

London’s rail and tube map is out of control

Aaaaaargh. Image: Getty.

The geographical limits of London’s official rail maps have always been slightly arbitrary. Far-flung commuter towns like Amersham, Chesham and Epping are all on there, because they have tube stations. Meanwhile, places like Esher or Walton-on-Thames – much closer to the city proper, inside the M25, and a contiguous part of the built up area – aren’t, because they fall outside the Greater London and aren’t served by Transport for London (TfL) services. This is pretty aggravating, but we are where we are.

But then a few years ago, TfL decided to show more non-London services on its combined Tube & Rail Map. It started with a few stations slightly outside the city limits, but where you could you use your Oyster card. Then said card started being accepted at Gatwick Airport station – and so, since how to get to a major airport is a fairly useful piece of information to impart to passengers, TfL’s cartographers added that line too, even though it meant including stations bloody miles away.

And now the latest version seems to have cast all logic to the wind. Look at this:

Oh, no. Click to expand. Image: TfL.

The logic for including the line to Reading is that it’s now served by TfL Rail, a route which will be part of the Elizabeth Line/Crossrail, when they eventually, finally happen. But you can tell something’s gone wrong here from the fact that showing the route, to a town which is well known for being directly west of London, requires an awkward right-angle which makes it look like the line turns north, presumably because otherwise there’d be no way of showing it on the map.

What’s more, this means that a station 36 miles from central London gets to be on the map, while Esher – barely a third of that distance out – doesn’t. Nor does Windsor & Eton Central, because it’s served by a branchline from Slough rather than TfL Rail trains, even though as a fairly major tourist destination it’d probably be the sort of place that at least some users of this map might want to know how to get to.

There’s more. Luton Airport Parkway is now on the map, presumably on the basis that Gatwick is. But that station doesn’t accept Oyster cards yet, so you get this:

Gah. Click to expand. Image: TfL.

There’s a line, incidentally, between Watford Junction and St Albans Abbey, which is just down the road from St Albans City. Is that line shown on the map? No it is not.

Also not shown on the map: either Luton itself, just one stop up the line from Luton Airport Parkway, or Stansted Airport, even though it’s an airport and not much further out than places which are on the map. Somewhere that is, however, is Welwyn Garden City, which doesn’t accept Oyster, isn’t served by TfL trains and also – this feels important – isn’t an airport.

And meanwhile a large chunk of Surrey suburbia inside the M25 isn’t shown, even though it must have a greater claim to be a part of London’s rail network than bloody Reading.

The result of all these decisions is that the map covers an entirely baffling area whose shape makes no sense whatsoever. Here’s an extremely rough map:

Just, what? Image: Google Maps/CityMetric.

I mean that’s just ridiculous isn’t it.

While we’re at it: the latest version shows the piers from which you can get boats on the Thames. Except for when it doesn’t because they’re not near a station – for example, Greenland Pier, just across the Thames to the west of the Isle of Dogs, shown here with CityMetric’s usual artistic flair.

Spot the missing pier. You can’t, because it’s missing. Image: TfL/CityMetric.

I’m sure there must be a logic to all of this. It’s just that I fear the logic is “what makes life easier for the TfL cartography team” rather than “what is actually valuable information for London’s rail passengers”.

And don’t even get me started on this monstrosity.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites.