Québec’s Ministère des Transports (MTQ) is responsible for highway management in the province, including regular inventory taking. Authorities often lack reliable information for this purpose. Inventories require a great deal of time and resources to update, which makes it hard to do so on a regular basis. Road sign inventories are a good example. MTQ turned to us to develop new technologies capable of conducting inventories quickly and efficiently.
Working with MTQ, we developed a new system that automatically generates road sign inventories. This system—known as RSR for Road Sign Recognition—automatically detects, recognizes, and localizes road signs from video images. This system accelerates inventory data extraction and review, thereby reducing the cost of accurate road sign surveys.
We are currently working to improve this first system so that it will be able to measure road sign dimensions and retroreflectivity, as well as automatically read texts and symbols on signs. This data will be incorporated into the final inventory and will allow managers to better plan their work.
One system, four modules
INO’s new road sign detection and recognition (RSR) system includes four basic modules, which are installed on a vehicle specially designed for video surveys. The four modules are:
An active road sign detection system
An acquisition system for color images and GPS location data
A geographic location system for detected signs
A system that recognizes and identifies detected signs
A three-step process
During the road survey, the system automatically detects the road sign using real-time image analysis software. At the same time, data required for localization and recognition (GPS position, color images, position of sign in image, etc.) is directly recorded on a PC in digital video format. After the survey, the RSR software automatically analyzes the collected data to generate inventory data.
Features tailored to market needs
Our detection system comes in a robust, waterproof housing to withstand bad weather. Surveys can be done at normal traffic speed during the day. Color image resolution is 640 x 480 pixels and data is recorded live at 15 frame/sec. The system readily adapts to any GPS receiver sending NMEA formatted data and is easy to calibrate. What’s more, it is designed so that new signs can be quickly and easily added to the database of objects to be recognized.