132 страниц. 2014 год. LAP Lambert Academic Publishing Challenges of Text Extraction in Video Document ... Although many methods have been proposed over the past years, text extraction in video document is still a challenging problem compared with a scanned document image because: (1)Video has complex background. (2)Color bleeding phenomena in video document. (3)Video often has low resolution. (4) Sometimes, the text has low contrast against background. (5) Unknown text color, size, position, orientation, and layout.