The infrared thermal imaging technology is widely used in road projects. Apart from the detecting function to the roadworks and its maintenance, the infrared thermal imaging technology also plays a significant role in daily road monitoring.The ordinary monitoring system is sufficient to monitor the road condition on a clear day. But it can do nothing in bad weather days such as rainy,snowy, foggy days or poor-light evenings. The infrared thermal imaging technology can eliminate the interference from natural environment outside. It uses infrared detectors to transform the driving targets and backdrop into grayscale image coordinate system and reflect the information of visual field by grayscale value. The radiation temperature of pedestrians and animals is usually higher than that of objects. Besides, it presents a much lighter imaging grayscale value and lighter backdrop of the image.The lower the temperature of the radiation, the smaller the grayscale of the image, and the darker the background in the image.
According to this principle, we designed the method of detecting and recognizing pedestrians on road based on car infrared night vision which can help to get the relative grayscale image coordinate position of the targets and backdrop in the same space-time. Then we take advantage of greyscale differences to do some processing in early stage which provides a possibility to recognize the targets and delivers an alert to drivers within dangerous distance. This research has enlarged driving view of drivers and warned potential dangers to them. It has certain practical value and important theory meaning in the aspect of improving assist in safe driving performance of cars.
We have mentioned in vehicle assisted driving that through combining the infrared thermal imaging technology and low light technology, using the mechanical and optical design, fixing the infrared thermal imaging devices on the surface of cars and output the video on LED screens through circuit processing, the driver could drive under the assist from the road image of LED screens. In addition, it avoids the disadvantage that the helmet-type low-light night vision device needs to be worn on the head during use, and overcomes the problem of fatigue caused by long-term use.
Thermal imaging technology application in highways monitoring has an advantage that the monitoring quality will not be affected by natural environment. So it will be better to handle real-time highways monitoring and improve driving safety factor. Thus,the thermal imaging technology has very important meaning to guarantee the life and property safety of drivers, passengers and pedestrians.