Apparatus and method for recognizing character

A method of recognizing a character, comprising:

• extracting a character string pattern from an image in a document or a listing;
• extracting a feature amount indicating a variance of line widths obtained by removing from the character string pattern a pattern within a predetermined distance from an end point, an intersecting point, and a corner point of a character stroke contained in the character string pattern, and a feature amount indicating a variance of character positions of the character string pattern;
• discriminating a hand-written character from a typed character based on at least the feature amount;
• and
• recognizing a character based on a discrimination result, wherein the variance of line widths is obtained for each stroke or a stroke direction.

A character recognition apparatus comprising:

• a character extraction unit extracting a character string pattern from an image in a document or a listing;
• a hand-written/typed character discrimination unit discriminating the character string pattern between a hand-written character and a typed character;
• and
• a character recognition unit recognizing a character based on a discrimination result, wherein
• said hand-written/typed character discrimination unit comprises:
• a complexity extraction unit extracting a feature indicating complexity of the character string pattern from the character string pattern;
• a linearity extraction unit extracting a feature indicating linearity of the character string pattern;
• a character position variance unit extracting a feature indicating a variance of character positions of the character string pattern;
• a discrimination unit discriminating the character string pattern between a hand-written character and a typed character based on N feature vectors containing at least a feature indicating the complexity, a feature indicating the linearity and a variance of character positions of the character string pattern, wherein said complexity extraction unit extracts a feature indicating the complexity by obtaining line density from the character string pattern.

A character recognition apparatus comprising:

• a character extraction unit extracting a character pattern from an image in a document or a listing;
• a hand-written/typed character discrimination unit discriminating the character string pattern between a hand-written character and a typed character;
• and
• a character recognition unit recognizing a character based on a discrimination result, wherein
• said hand-written/typed character discrimination unit comprises:
• a line width variance extraction unit extracting a feature amount indicating a variance of line widths obtained by removing from the character string pattern a pattern within a predetermined distance from an end point, an intersecting point, and a corner point of a character stroke contained in the character string pattern;
• a character position variance unit extracting a feature indicating a variance of character positions of the character string pattern;
• a discrimination unit discriminating the character string pattern between a hand-written character and a typed character based on at least a feature amount indicating the variance of line widths and a variance of character positions of the character string pattern, wherein said line width variance extraction unit obtains the variance of line widths for each stroke or stroke direction.

A character recognition apparatus, comprising:

• a feature identification unit identifying a feature of a characterizing pattern extracted from an input image;
• a hand-written character recognition unit character-recognizing a hand-written character;
• a typed character recognition unit character-recognizing a typed character;
• and
• a character recognition selection unit selecting one of said hand-written character recognition unit and said typed character recognition unit based on an identification result from said feature identification unit, wherein:
• said feature identification unit discriminates the pattern between a hand-written character and a typed character based on regularity of a pattern;
• a feature of the pattern contains at least one of complexity, linearity, variance of line widths, variance of arrangement positions, variance of tilts, variance of sizes, variance of character positions of the pattern;
• said complexity contains at least one of line density, density of black picture elements, an Euler number, and an outline length;
• and
• said linearity is computed based on a number of lines longer than a predetermined length in the pattern.

A computer-readable storage medium storing a character recognizing program for recognizing a character string pattern extracted from an image in a document or a listing, wherein

• said character recognizing program directs a computer to perform operations of:
• extracting a feature indicating complexity of the character string pattern;
• extracting a feature indicating linearity of the character string pattern;
• extracting a feature indicating a variance of character positions of the character string pattern;
• obtaining, from the character string pattern, N feature vectors containing a feature indicating at least complexity, linearity and a variance of character positions of the character string pattern;
• and
• discriminating the character string pattern between a hand-written character and a typed character using the feature vectors, wherein line density is used as a feature indicating the complexity.

A computer-readable storage medium storing a character recognizing program for recognizing a character string pattern extracted from an image in a document or a listing, wherein

• said character recognizing program directs a computer to perform operations of:
• extracting a feature amount indicating a variance of line widths obtained by removing from the character string pattern a pattern within a predetermined distance from an end point, an intersecting point, and a corner point of a character stroke contained in the character string pattern, and a feature amount indicating a variance of character positions of the character string pattern;
• and
• discriminating a hand-written character from a typed character based on at least the feature amount, wherein said variance of line widths is obtained for each stroke or a stroke direction.

A character recognition method, comprising:

• extracting a character string pattern from an image;
• identifying a feature of the character string pattern extracted from the image;
• and
• determining whether a character is a handwritten character or a typed character based on at least the identified feature, wherein said identifying comprises:
• extracting a feature amount indicating a variance of line widths obtained by removing from the character string pattern a pattern within a predetermined distance from an end point, an intersecting point and a corner point of a character stroke contained in the character string pattern;
• extracting a feature indicating complexity of the character string pattern;
• extracting a feature indicating linearity of the character string pattern;
• extracting a feature indicating a variance of character positions of the character string pattern;
• obtaining feature vectors containing a feature indicating at least complexity, linearity and a variance of character positions of the character string pattern, and wherein said determining is performed by using the feature vectors.