| 摘要 |
PURPOSE:To evaluate the smoothness of a body surface on the basis of a numeral obtained by quantizing edge line shapes of slit light images projected on the body surface. CONSTITUTION:The surface 10 on which the slit light images 11-15 are projected is picked up and variable density information G(x,y) is developed in a memory corre sponding to a range V. Picture elements of each (y) coordinate are retrieved in an (x) direction to detect a picture element where G(x,y) crosses a threshold value Gth, and then light parts (hatched) correspond to edge lines 11a and 11b of the light image 11. Thus, pieces of position information xe1(1) and ye1(1) where G>Gth firstly are stored in registers as to an (y) coordinate 1 after edge line extraction, and 0 is set in a path register DL. Then, 1 when a next picture element is right below the last picture element or 2<1/2> when slantingly below is added to DL every; time G>Gth, and xen(1) and yen are stored at a lower end; and the distance DS(1) between a start point P11 and an end point Pen is found, the ratio R(1) to the distance DL is calculated, and the (y) coordinate is increased to complete the processing of the picture element sequence of an edge line 15b. Then, the mean value Rm of R(i) is calculated. When edge lines are distorted greatly, the DL value increases and Rm also increases. When they are flat, Rm=1 and the surface smoothness is evaluated from Rm. |
