World first for Vauxhall
It's all done through a camera, not much bigger than a mobile phone, mounted between the windscreen and the rear-view mirror.
It has a wide-angle lens, so it can read signs at the roadside and centre lane markings simultaneously, and can take 30 pictures a second.
Depending on the available light, it begins to read road signs from a distance of 100 metres, and when it recognises a number, it displays it on the instrument panel.
No-overtaking signs are given priority over speed limits.
The system, developed in partnership with lighting specialists Hella, also acts as a lane-departure warning system, giving an audible and visual alert if you inadvertently stray off course.