An efficient realtime video compression algorithm with high feature preserving capability

Mobile Phones and other hand held devices are constrained in their memory and computational power, and yet new generations of theses devices provide access to the web-based services and are equipped with digital cameras that make them more attractive to users. These added capabilities are expected to help incorporate such devices into the global communication system. In order to take advantage of these capabilities, there are desperate need for highly efficient algorithms including real-time image and video processing and transmission. This paper is concerned with high quality video compression for constrained mobile devices. We attempt to tweak a wavelet-based feature-preserving image compression technique that we have developed recently, so as to make it suitable for implementation on mobile phones and PDA's. The earlier version of the compression algorithm exploits the statistical properties of the multi-resolution wavelet-transformed images. The main modification is based on the observation that in many cases the statistical parameters of wavelet subbands of adjacent video frames do not differ significantly. We shall investigate the possibility of re-using codebooks for a sequence of adjacent frames without having adverse effect on image quality if any. Such an approach results in significant bandwidth and processing-time savings. The performance of this scheme will be tested in comparison to other video compression methods. Such a scheme is expected to be of use in security applications such as transmission of biometric data for a server-based verification.