| 摘要 |
PROBLEM TO BE SOLVED: To reduce the data volume to increase the detection speed by handling a bit pattern string as data having a bit length corresponding to the number of rectangular areas to detect entrance and passage of a vehicle. SOLUTION: A correlation operation circuit 5 takes the output of a rectangular area segmenting circuit 3 and the output of a rectangular area reference memory 4 as the input to calculate a normalization correlation value for each rectangular area. A bit pattern generation circuit 6 discriminates the absence of a change to generate '0' if the normalization correlation value of each rectangular area outputted from the correlation operation circuit 5 is larger than a preliminarily set threshold, but the circuit 6 discriminates the presence of a change to generate '1' if it is smaller than this threshold. An entrance and passage discrimination circuit 7 handles the bit pattern of each rectangular area as data of 5 bits in this case and discriminates the going condition of the vehicle in accordance with a numerical value (0 to 31) expressed by 5 bits. Thus, entrance and passage of the vehicle are quickly detected in accordance with entrance and passage patterns preliminarily assigned to each data. |
