Speech frame detection using color information of lip regions and features of lip motion

Abstract

Lip motion features such as lip width and lip length provide important information to identify individuals or commands. Previous study has proposed recognition system that used L*a*b color space to acquire lip information. However, the interface using lip motion features has not achieved automatic detection of speech activity. Therefore, we propose a method to detect speech frames using color information of lip region and features of lip motion. The proposed method has three steps. First, it extracts the lip motion features on the basis of both position and shapes of lip in each frame of facial images. Second, it judges the existence of oral slit in each frame of lip images by color information of lip vertical lines. Third, it detects differences of lip length between three frames: the object frame which has oral slit and two previous frames. The experimental results for five persons show that the proposed method is able to detect speech frames with an accuracy of 99.2 percent.