6. The method of claim 4 , wherein: the text characters in the line of text characters have a same size, a same rotation angle, and a same font; and more than half of the text characters in the line of text characters are commonly used characters.
4. A method of generating a text line classifier, the method comprising: selecting a plurality of text characters from a font reservoir; varying an aspect of the plurality of text characters to form a plurality of character samples; randomly arranging a number of character samples from the plurality of character samples to form a line of character samples; varying an aspect of the line of character samples to form a line of text characters; and extracting from the line of text characters one or more of a gradient orientation histogram feature, a gradient magnitude histogram feature, a pixel histogram feature, and a pixel histogram change feature.