A traffic survey algorithm of video virtual loop

In traffic survey, video is easier to install and maintain than loop and microwave. It can provide visual picture also. The article combine the loop and video, present a new approach of traffic survey which base on the gray statistical characteristic value of the current frame subtracts the background. It generate the virtual wave base on the grayscale of the current frame subtracts the background, then revise the wave, and get the vehicle´s flux, speed and length.