US 6,473,524 B1 · Optical object recognition method and system

Abstract

An iterative application of an optical object recognition method, such as an OCR method, with enhancements and modifications yields improved speed and accuracy. In the exemplary embodiment, after an initial pass of the OCR method on a document image, unrecognized blobs are grouped into unknown regions to which the OCR method is applied via an analysis window. If the contents of the analysis window remain unrecognized at a starting position in a given unknown region, the window can be moved within the unknown region to provide more opportunities to recognize the unknown region's contents. Recognized characters are recorded, and the portions of the unknown regions in which they appeared are removed. This pass of the OCR method recognizes characters in blobs containing multiple characters. After all unknown regions have been analyzed, remaining unrecognized blobs are regrouped into new unknown regions according to particular relationships, such as spatial or spectral relationship, and predetermined criteria, such as relative distance or frequency distribution. The OCR method is then applied to the new unknown regions. This pass of the OCR method recognizes characters that have been split into multiple blobs.

Claims49

Dependent claims

An optical object recognition method applying a post-processing method to blobs parsed within a region of interest in an array of data and remaining after an initial pass of a recognition routine, the method including the steps of:

(a). dividing the region of interest into unknown regions by:
(i). locating and defining a first end point of a dimension of each unknown region as a beginning of an unrecognized blob including a portion of the array of data from the region of interest analyzed by an optical object recognition routine that yielded no recognized objects;
(ii). locating and defining a second end point of the dimension of each respective unknown region as a point at which unrecognized data stops;
and
(iii). defining each unknown region as extending between respective first and second end points;
(b). analyzing each unknown region with a modified optical object recognition method by:
(i). placing an analysis window over a portion of the unknown region;
(ii). performing a correlation between a contents of the analysis window and a reference set of objects to determine whether the analysis window contains a recognizable object;
(iii). removing the contents of the analysis window from the unknown region if the analysis window contains a recognizable object and recording a recognized object;
(iv). moving the analysis window over a new portion of the unknown region if a remaining portion of the unknown region is larger than a predetermined size;
and
(v). repeating steps (ii)-(iv) until the remaining portion of the unknown region is smaller than the predetermined size;
and
(c). repeating steps (a) and (b) until all unknown regions have been analyzed.

11 more elements

An optical object recognition method including the steps of:

(a). performing an initial OOR on a region of interest in an array of data;
(b). defining unrecognized blobs as portions of the region of interest containing substantially contiguous data from the array distinguished by yielding no recognized objects from the initial OOR;
(c). performing a first post-processing method on unrecognized blobs left from the initial OOR to separate objects from unrecognized blobs including more than one object;
(d). recognizing more than one object within at least one of the unrecognized blobs;
(e). performing a second post-processing method on unrecognized blobs left from the initial OOR and the first post-processing method to recognize objects split into multiple unrecognized blobs;
and
(f). recognizing at least one single object split between more than one of the unrecognized blobs.

4 more elements

An optical object recognition method including the steps of:

(a). performing an initial OOR on a region of interest in an array of data;
(b). performing a first post-processing method on unrecognized blobs left from the initial OOR to separate objects from unrecognized blobs including more than one object;
(c). performing a second post-processing method on unrecognized blobs left from the initial OOR and the first post-processing method to recognize objects split into multiple unrecognized blobs;
(d). the second post-processing method including the steps of:
(i). determining relationships between unrecognized blobs left over from an initial optical object recognition and the first post-processing method;
(ii). dividing the region of interest into unknown regions by:
(A). defining an unknown region as extending from a first point to a second point and including multiple unrecognized blobs when the relationships between the unrecognized blobs meet predetermined criteria;
(B). the first point being a beginning of an unrecognized blob left over from an initial optical object recognition, the blob containing a portion of an array of data analyzed by the initial optical object recognition routine that yielded no recognized objects;
and
(C). the second point being a point at which unrecognized data ends;
and
(D). repeating steps (A) through (C) until substantially all unrecognized blobs in the region of interest have been grouped into unknown regions;
(iii). analyzing each unknown region with a modified optical object recognition method;
and
(iv). repeating steps (i) through (iii) until substantially all unknown regions have been analyzed.

12 more elements

An optical object recognition method applying an OOR routine iteratively on a target document image including a region of interest, a first iteration of the OOR method leaving unrecognized blobs including portions of the target document image, the method including the steps of:

(a). dividing the unrecognized blobs in the region of interest into unknown regions each occupying contiguous areas among the unrecognized blobs;
(b). selecting one of the unknown regions in the region of interest;
(c). analyzing the unknown region with the OOR routine via an analysis window;
(d). removing a portion of the unknown region bounded by the analysis window if it includes a recognized object and recording any such recognized object in a memory;
(e). determining if the remaining unknown region is still large enough to include an object;
(f). moving the analysis window to a new part of the unknown region if the remaining unknown region is still large enough to include an object;
(g). repeating steps (c) through (f) until the remaining unknown region is not large enough to include an object;
(h). selecting another of the unknown regions in the region of interest for analysis;
and
(i). repeating steps (c) through (h) until substantially all of the unknown regions in the region of interest have been analyzed.

7 more elements

Dependencies are inferred from the claim text.

Optical object recognition method and system

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Optical object recognition method and system

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Abstract

Claims49