| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and a device for measuring random noise of an input image for measuring random noise through high speed arithmetic processing and performing accurate arithmetic operations even when the number of data is small. SOLUTION: An adder 30 and a divider 40 generate average data of the number T of images out of a group of T+1 images received by a frame memory 20, and a subtractor 50 generates difference data between the one remaining image and the average data. A multiplier 60 multiplies a value [T/(T+1)] with the variance of the difference data to calculate a random noise power. Thus, the random noise can be calculated by two times of multiplication and division and T times of addition and subtraction, the arithmetic amount can be reduced more in comparison with a first conventional example and high speed processing can be realized. Further, the random noise can accurately be measured even with the number of images less than that of a second conventional example. COPYRIGHT: (C)2003,JPO |
