A new chain code

A new chain code for shapes composed of regular cells is defined. This boundary chain code is based on the numbers of cell vertices which are in touch with the bounding contour of the shape. This boundary chain code is termed cei res chain code (VCC). The VCC is invariant under translation and rotation. Also, it may be starting point normalized and invariant under mirroring transformation. Using this concept of chain code it is possible to relate the chain length to the contact perimeter, which corresponds to the sum of the boundaries of neighboring cells of the shape (Bribiesca, E., Comp. Math. Appl. 33(11) (1997) 1-9); also, to relate the chain nodes to the contact vertices, which correspond to the vertices of neighboring cells. So, in this way, these relations among the chain and the characteristics of interior of the shape allow us to obtain interesting properties. This work is motivated by the idea of obtaining various shape features computed directly from the VCC without going to Cartesian-coordinate representation. Finally, in order to illustrate the capabilities of the VCC: we present some results using real shapes. (C) 1999 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved.