High speed character matcher and method
AssigneeCompression Labs, Inc.
InventorsRonald S. Bader, Lyle V. Rennick, Robert H. Wallis
Life of this patent
Estimating the term…
Abstract
A high speed character matcher and method for measuring the similarity between a pair of binary patterns representing two-dimensional images. The patterns are compared on a bit by bit basis and when a discrepancy is detected, it is assigned an error penalty which is based on the two-dimensional context in which the error occurred. The types of error context which are typical in the comparison of distorted but otherwise similar characters are given a lower error than those typically encountered in the comparison of dissimilar characters.
Claims13
In a high speed character matching apparatus, the method comprising the steps of storing digital pixel data representing first and second characters, respectively, forming an array for each pixel of said first and second characters where each pixel of said first and second characters is the center element of said array surrounded by its nearest neighboring pixels, determining whether each center pixel is in a first state, determining whether any pixel in the corresponding array of said second character is in said first state or in a second state, different from said first state, and counting the number of pixels of said center pixel and said corresponding array when said pixels are in said first state.
High speed character matching apparatus comprising means for storing digital pixel data representing first and second characters, respectively, means for forming an array for each pixel of said first and second characters where each pixel is the center element of said array surrounded by the nearest neighboring pixels, means for determining whether each center pixel is in a first state, means for determining whether any pixel in the corresponding array of said second character is in said first state or in a second state, different from said first state, and means for summing the number of pixels of said center pixel and said corresponding array when said pixels are in said first state.
In a character matcher, the method comprising the steps of storing digital pixel data representing first and second characters, respectively, forming an array for each pixel of said first and second characters where each pixel is the center element of said array surrounded by the nearest neighboring pixels, determining whether each center pixel is in a first state, determining whether all pixels in the corresponding array of said second characters are in said first state or in a second state, different from said first state, and summing the number of pixels of said center pixel and said corresponding array when said pixels are in said first state, and determining whether any of said center pixels of said first character are in a different state than the corresponding center pixel of said second character.
A high speed character matching apparatus comprising means for storing digital pixel data representing first and second characters, respectively, means for forming an array for each pixel of said first and second characters where each pixel is the center element of said array surrounded by its nearest neighboring pixels, means for determining whether each center pixel is in a first state, means for determining whether any pixel in the corresponding array of said second character is in said first state or in a second state, different from said first state, and means for summing the number of pixels of said center pixel and said corresponding array when said pixels are in said first state.
Dependencies are inferred from the claim text.