| 摘要 |
A traffic detector system comprises an imaging means (40,42) directed generally downwardly to observe a detection zone and arranged to acquire spaced images from respective spaced viewpoints. An image processing device processes the spaced images acquired by said imaging means to detect the presence of an object of appreciable height in said detection zone. The image processing device acquires respective image frames (44,46) each containing an array of pixels, and processes each of said arrays on a block by block basis to obtain a variance value which is dependant on the variation of the pixel values within the respective left and right blocks. The image processing device compares the values of corresponding pixels in the left and right blocks and outputs a detection active signal for that block if the differences between the pixels from the two blocks exceed a threshold that depends on said variance value. The detection active signals are monitored and a detection signal output if there are more than a preset proportion of blocks showing detection active signals. |
