What system uses a camera to read traffic signs and display speed limits?

A traffic sign recognition system uses a camera to read traffic signs and display speed limits to the driver.

The system is an advanced driver-assistance feature. A forward-facing camera detects signs, then image-processing software classifies their colors, shapes and symbols. The resulting information may appear in the instrument cluster, head-up display or navigation screen.

Speed-limit recognition was an early practical application. The feature appeared on the 2009 Vauxhall Insignia and later spread to models from BMW, Mercedes-Benz, Volkswagen, Volvo and many other manufacturers. Modern systems increasingly use machine-learning models trained on large collections of road-sign images.

A common mix-up is intelligent speed assistance. Traffic sign recognition reads or identifies the sign; intelligent speed assistance may use that information to warn the driver or adjust the vehicle's speed. Navigation databases can supplement camera readings, but they are not the camera-recognition system itself. Performance can be affected by glare, dirt, faded signs, unusual sign designs or blocked views.