AN EFFICIENT, PARALLEL-SYMMETRIC THINNING ALGORITHM AND ITS HARDWARE IMPLEMENTATION

This paper presents an efficient, parallel-symmetric thinning algorithm (PSTA), which is a modification of the one-pass thinning algorithm (OPTA), and its hardware implementation. The OPTA algorithm is applied on raster scanned binary images, using a set of 10 thinning patterns of 3 multiplied by 3 and 3 multiplied by 4 predefined elements, and produces the skeleton of their objects. The OPTA hardware implementation has been done using a combinatorial circuit. Both the PSTA and OPTA algorithms are implemented sequentially in software for comparison purpose in accuracy (using ideal skeletons), memory requirements and execution time. The hardware implementation of the PSTA is also provided using a 2-D hardware processing array.