Patent ID: 7403657

Claim:
A method for searching at least one character string image in an image, comprising: providing a first image; detecting a character region in the first image based upon a shape thereof; extracting a first image feature of the character region, said first image feature containing image sub-features of a character string; receiving an input of a character string of interest by a user; generating a second image of said character string of interest; extracting a second image feature from the second image, said second image feature containing image sub-features of said character string of interest; comparing the first image feature with the second image feature to determine a level of similarity therebetween without breaking down the first and second image features per character into separate characters; and outputting the character region or the first image comprising the character region based on the level of similarity, wherein both the first image feature and the second image feature to be extracted are one-dimensional feature strings whose numbers of edges in a vertical direction are obtained by binarizing luminance of each pixel and counting numbers of luminance changes in the character regions, when the character strings are arrayed horizontally, and the step of determining a level of similarity involves elastic matching of the one-dimensional feature strings both of which constitute the first image feature and the second image feature.