Very Low Rate Video Processing

Web cameras are becoming more and more common on the Internet, and the technology is ready to make cameras a standard accessory of any computer. The development of applications, however, hasn’t followed the explosive diffusion of the cameras. Problems in developing applications for remote web cameras come from the low image quality that they generally provide and from the fact that, unless the application runs locally, the image data are only available at a very low frame rate (typically between 10 sec/image and 30 min/image). New image analysis and processing techniques are needed to take advantage of the opportunity represented by web cameras. This paper presents some early considerations and techniques to deal with what I call ”Very Low Rate Video” (VLRV). Certain operations of fundamental importance in vision, such as motion detection, are impossible in VLRV, due to the large interval between consecutive images. Other operations, like color processing, are made difficult by the low quality and temporal instability of the images. The paper presents techniques to deal with different processes with different time constants, and tries to determine the limits of what is feasible using one web camera and using a whole collection of web camerass.