| 摘要 |
PURPOSE:To decide a threshold value even for a histogram without a clear bottom by setting the threshold value of a reference image as that of a similar image by moving the density allocation of the similar image so that the feature position of the historgam of the reference image can coincide with that of the histogram of the similar image. CONSTITUTION:This method is to set the threshold value of the similar image equal to that of the reference image and to move the density level of the similar image so that the density of feature position of the reference image can coincide with that of the similar image, and the centroid of the histogram is used as the feature position. In other words, difference DELTAX=x2-X1 between the centroid G1, G2 is found assuming the area centroid of the histogram of the reference image as G1, the horizontal coordinate(density) of it as X1, the area centroid of the histogram of the similar image as G2 and the horizontal coordinate of it as X2, and it is subtracted from the density of each picture element of the similar image. Also, it is subtracted from an absolute value when DELTAX shows a positive value, and added on the absolute value when it shows a negative value. In this way, coincidence between the centroid G1 and G2 can be obtained by moving the density of the similar image by DELTAX. |
