Camera and computer vision software instead of switches for activating walk signs?

Philip Greenspun's Weblog 2017-07-15

Here’s my dumb question for today…

We are smart enough to build self-driving cars, right? That’s a camera and computer vision software that needs to see everything happening on the road, including pedestrians.

It doesn’t take specialized training for a human to work as a crossing guard, right? The human sees a pedestrian approaching an intersection, walks out into the crosswalk holding a STOP sign, and stops the traffic.

Why would we wire up the light poles surrounding intersections with switches to activate WALK signs? Why not mount a camera up on the pole to watch for approaching pedestrians? Then, if no cars are coming, turn the light red for cars and activate the WALK sign before the pedestrian has to break stride.

How hard can this be? Maybe this could ease traffic congestion slightly by making it more pleasant to walk. At a minimum, we could save a lot of money installing and maintaining the under-pavement sensors for cars. The same camera can simply watch for a car approaching or stopping at an intersection. That should also save fuel (and the planet!) by changing the light before the car has to hit its brakes.

Camera plus microprocessor plus software should be cheaper than sensors, wires, and maintenance, no?