提取视频中定义的一帧，提取视频中所有镜头切换的帧-Extraction definition video one frame, all lenses extract video frames switched

视频关键帧提取，通过视频图像帧的颜色直方图来提取视频中的关键帧。-Video key frame extraction, through the video image frames of color histogram to extract the key frames in the video.