Overlay Text Detection in Complex Video Background

The subtitles on video are very useful for us to understand video's contents. If we can extract text information from the subtitles, it will be very helpful to establish a database of video’s content that includes annotations and indexes. To extract text from videos, most text detection and extraction methods use the text color, background contrast, and texture information. However, the limitations of the existing methods are various contrasts and complex backgrounds in the text processing. The purpose of this study is to develop a method to detect overlay text in the complex video background. This study utilized the characteristics that there are transient color changes existing between text and its adjacent background, to generate transition maps. And this work applied the connected components to smooth the connected rectangular shapes. The study results demonstrated that the text detection method based on the transition map can effectively detect the text regions under different text contrasts, fonts and background complexities.