In order to extract the subtitle in the video image, a robust method was proposed. First, the image edge feature was adopted in caption location step, and the binarization method of text images with the edge information was given. Then, the method combined with projection and regional generation was used to locate a character. Finally, taking fully account of the topology of the text strokes, the stroke correlation among the adjacent sub-grids was determined and the stroke fuzzy membership was used to complete the elastic grid feature extraction. This method can effectively get the binary image of characters from a complex background image, ensure the stability and robustness in feature extraction. The experimental results show the method is effective, and its recognition rate has been up to 92.1%.