a system that captures both whiteboard content and audio signals of a meeting using a video camera and records or transmits them in real - time . the real - time whiteboard capture captures pen strokes on whiteboards in real time using an off - the - shelf video camera . unlike many existing tools , the rtwcs does not instrument the pens or the whiteboard . it analyzes the sequence of captured video images in real time , classifies the pixels into whiteboard background , pen strokes and foreground objects , and extracts newly written pen strokes . this allows the rtwcs to transmit whiteboard contents using very low bandwidth to remote meeting participants . combined with other teleconferencing tools such as voice conference and application sharing , the rtwcs becomes a powerful tool to share ideas during online meetings .