US 6,950,555 B2 · Holistic-analytical recognition of handwritten text

Abstract

In a combined holistic and analytic recognition system, the holistic recognition module will recognize an input word or phrase image by matching an input string of character features for the whole word or phrase against a string of prototype features for a plurality of reference words in a lexicon. This will yield a holistic answer list of recognized word or phrase candidates for the input word or phrase along with a confidence value for each answer on the list. At the same time based on each answer in the answer list, the holistic recognition modules will generate a list of character features and segment the character features into sets for each character in an answer. The analytical recognition module uses segmentation hypotheses from the segmented character feature sets to cut the image of the input string of characters into individual character images. A plurality of character images for the various segmentation hypotheses will be recognized to produce an analytical answer list having a plurality of word or phrase answers for the input word or phrase. Each analytic word answer will have a confidence value based on the combined confidence of recognizing each character. The holistic answer list and the analytic answer list will be examined to find the best answer from the two lists as the recognition of the input handwritten text.

Claims13

Dependent claims

Apparatus for recognizing a string of characters of hand written text in an image loaded in a computing system, the apparatus comprising:

holistic recognition means for recognizing the string of characters as a whole and generating a first answer list and a segmentation list, the first answer list containing a plurality of recognition answers for the string of characters in the image each answer having a confidence value that the answer is correct, the segmentation list containing segmentation information separating each character in the answers;
analytical recognition means responsive to the segmentation list for recognizing a plurality of characters individually and generating a second answer list for the string of characters in the image each answer having a confidence value that the answer is correct;
and
means responsive to the first answer list and the second answer list for finding the best recognition answer for the string of characters.

1 more element

In a computing system for processing information loaded as cursive text, a method for recognizing the cursive text to provide digital information corresponding to the cursive text, the method comprising:

loading into the computing system an image of an input phrase of cursive text;
identifying features of the input phrase, each feature representing at least a portion of a character in the input phrase;
matching features of the input phrase against features of a plurality of reference phrases and generating a holistic answer list containing as answers reference phrases that are most similar to the input phrase along with a confidence value, the confidence value for each answer being a measure of similarity between features of the input phrase and the features of the reference phrase;
constructing a character segmented features list from the features of the input phrase and from the holistic answer list, the character segmented features list being a list of character feature sets segmented by characters in each answer from the holistic answer list;
translating the image of the input phrase into images of characters segmented according to answers in the holistic answer list based upon the character segmented features list;
analytically recognizing characters in the input phrase from the images of characters segmented according to answers in the holistic answer list and generating an analytical answer list containing analytical answers for the input phrase, each analytical answer having a confidence value as a measure of the similarity between characters in the analytical answer and characters in a reference phrase;
and
finding the best recognition answer from the answers on both the holistic answer list and the analytic answer list.

5 more elements

In a handwritten character recognition system a method for recognizing an input word of handwritten text in an image provided to the recognition system, the method comprising:

identifying from the input word image an input string of metastrokes where each metastroke represents a portion of an alphanumeric character in the text;
storing the input string of metastrokes as character feature images;
comparing as a whole the input string of metastrokes to a prototype string of metastrokes for reference words to generate a first recognition answer list having a plurality of possible answers;
creating a plurality of character segmentation hypothesis based on character segmented metastrokes for answers in the first recognition answer list;
translating each character segmentation hypothesis into character cutout images of the input word;
recognizing characters from the character cutout images and generating a plurality of character variants for each character position in the input word based on each segmentation hypothesis;
interpreting the plurality of character variants of the input word for each segmentation hypothesis based on a vocabulary and generating a second recognition answer list having a plurality of possible answers;
and
finding a best answer from the first and second answer lists as the recognition of the input word.

6 more elements

Dependencies are inferred from the claim text.

Holistic-analytical recognition of handwritten text

Life of this patent

Holistic-analytical recognition of handwritten text

Life of this patent

Abstract

Claims13