ABSTRACT
This chapter focuses on the design and components of the system and the algorithm used to search the edge of a particle profile. In order to examine whether a threshold value is correctly selected, the program has been written to show the extracted edge immediately superimposed on the particle image being digitized. A limitation of the technique is that the lowest gray level of the background around the desired particle image must be higher than the highest gray level of the object edge. The EDGE4 program will automatically digitize all the particles shown on the Ramtek, one by one, and kick out the unwanted particles. In order to detect the edge, three programs named EDGE4, EDGE5, and EDGE5B were written in FORTRAN, based on the concept of "contour following". Running EDGE5, the user will have to enter the cursor position through the cursor controller of the Ramtek to denote which particle on the Ramtek is to be traced.
