A Character Detection Algorithm in DCT Domain for Video

A DCT-domain based character detection algorithm is proposed for video stream. It utilizes the directional features of the texture in character blocks and the property that the characters in video usually distribute in row or column. The character/non-character blocks are effectively separated by a new adaptive threshold, then the noise and false text regions are further removed by morphological operation. Finally, the text regions are accurately obtained by horizontal and vertical projection. Experimental results demonstrate that the proposed approach can detect characters accurately even in video with complex background , and it is of good robustness and high practical value.