Apparatus and method for pattern recognition

A method for recognizing patterns in a trial image comprising:

• scanning in a model image and storing said scanned-in model image in an image buffer;
• extracting region image blocks from said model image stored in said image buffer and storing said extracted region image blocks in a region buffer;
• translating and rotating said region image blocks to create additional region image blocks for storage in said region buffer;
• extracting characteristics of said region image blocks of said model image;
• storing characteristics of said region image blocks of said model image, said region image blocks having respective coordinates in said coordinate space;
• scanning in a trial image and extracting features from window image blocks in said trial image, said window image blocks having respective coordinates in a coordinate space;
• comparing said extracted features to said characteristics of said region image blocks and indicating features similar to said region characteristics;
• storing coordinates of window image blocks with features indicated by said comparator as having similar region characteristics and storing coordinates of corresponding similar regions;
• determining a window image block geometric relationship between at least two window image blocks from said respective coordinates and determining a region geometric relationship between at least two corresponding regions from said respective coordinates;
• and
• comparing said window image block geometric relationship to said region geometric relationship and recognizing said trial image as corresponding to said model image when said window image block geometric relationship is the same as said region geometric relationship.

A medium readable by a machine embodying a program of instructions executable by said machine to perform a method of recognizing patterns in a trial image, said pattern recognizing method comprising:

• scanning in a model image and storing said scanned-in model image in an image buffer;
• extracting region image blocks from said model image stored in said image buffer and storing said extracted region image blocks in a region buffer;
• translating and rotating said region image blocks to create additional region image blocks for storage in said region buffer;
• extracting characteristics of said region image blocks of said model image;
• storing characteristics of said region image blocks of said model image, said region image blocks having respective coordinates in said coordinate space;
• scanning in a trial image and extracting features from window image blocks in said trial image, said window image blocks having respective coordinates in a coordinate space;
• comparing said extracted features to said characteristics of said region image blocks and indicating features similar to said region characteristics;
• storing coordinates of window image blocks with features indicated by said comparator as having similar region characteristics and storing coordinates of corresponding similar regions;
• determining a window image block geometric relationship between at least two window image blocks from said respective coordinates and determining a region geometric relationship between at least two corresponding regions from said respective coordinates;
• and
• comparing said window image block geometric relationship to said region geometric relationship and recognizing said trial image as corresponding to said model image when said window image block geometric relationship is the same as said region geometric relationship.

A system for comparing a trial document to a model document and for preventing copying of a trial document matching said model document comprising:

• a scanner for scanning in said model document and said trial document;
• an image buffer for storing a scanned-in model document;
• a region extractor for extracting region image blocks from said model document stored in said image buffer and a region buffer for storing said extracted region image blocks;
• an affine transformer for translating and rotating said region image blocks to create additional region image blocks for storage in said region buffer;
• a feature extractor for extracting trial document features from window image blocks in said trial document and for determining characteristics of said region image blocks of said model document, said window image blocks having respective coordinates in a scan coordinate space;
• a memory for storing said characteristics of said region image blocks of said model document, said region image blocks having respective coordinates in said scan coordinate space;
• a similarity comparator for comparing said extracted features to said characteristics of said region image blocks and for indicating features similar to said region characteristics;
• a candidate list for storing coordinates of window image blocks with features indicated by said comparator as having similar regions and for storing coordinates of corresponding similar regions;
• an analyzer for determining a window image block geometric relationship between at least two window image blocks in said candidate list from said respective coordinates and for determining a region geometric relationship between at least two corresponding regions from said respective coordinates;
• and
• a geometry comparator for comparing said window image block geometric relationship to said region geometric relationship for recognizing said trial document as matching said model document when said window image block geometric relationship is the same as said region geometric relationship;
• a printer;
• an action unit coupled to said geometry comparator and said printer for preventing copying of said trial document if it matches said model document.

A system for comparing a trial document to a model document and for preventing copying of a trial document matching said model document comprising:

• an input device for inputting an image of said model document and an image of said trial document;
• an image buffer for storing an input model document;
• a region extractor for extracting region image blocks from said model document stored in said image buffer and a region buffer for storing said extracted region image blocks;
• an affine transformer for translating and rotating said region image blocks to create additional region image blocks for storage in said region buffer;
• a feature extractor for extracting trial document features from window image blocks in said trial document and for determining characteristics of said region image blocks of said model document, said window image blocks having respective coordinates in a scan coordinate space;
• a memory for storing said characteristics of said region image blocks of said model document, said region image blocks having respective coordinates in said scan coordinate space;
• a similarity comparator for comparing said extracted features to said characteristics of said region image blocks and for indicating features similar to said region characteristics;
• a candidate list for storing coordinates of window image blocks with features indicated by said comparator as having similar region characteristics and for storing coordinates of corresponding similar regions;
• an analyzer for determining a window image block geometric relationship between at least two window image blocks in said candidate list from said respective coordinates and for determining a region geometric relationship between at least two corresponding regions from said respective coordinates;
• and
• a geometry comparator for comparing said window image block geometric relationship to said region geometric relationship for recognizing said trial document as matching said model document when said window image block geometric relationship is the same as said region geometric relationship;
• an output device;
• an action unit coupled to said geometry comparator and said output device for preventing copying of said trial document if it matches said model document.