Ching-Huei Wang, Paul W. Palumbo, Sargur N. Srihari
The objective of an Address Block Location System (ABLS) is to determine the position and orientation of a destination address block in a mail piece image of either a letter, magazine, or parcel. The corresponding sub-image can then be presented to either a human or machine reader (OCR) to direct the mail piece to the appropriate sort category based on the ZIP code. ABLS is capable of dealing with a wide range of environments from those having a high degree of global spatial structure to those with no structure. The system consists of several specialized tools and a control structure so that the tools are opportunistically invoked and coordinated. Its performance on a training and testing image database of difficult cases is described.