Distributed Coding of Highly Correlated Image Sequences with Motion-Compensated Temporal Wavelets

This paper discusses robust coding of visual content for a distributed multimedia system. We investigate how scene analysis at the decoder can improve the coding efficiency. The distributed system encodes independently two correlated video signals and reconstructs them jointly at a central decoder. The video signals are captured from a dynamic scene where each signal is temporally decorrelated by a motion-compensated Haar wavelet. The two cameras operate independently, however, the central decoder is able to exploit the coded information from all cameras to achieve the best reconstruction of the correlated video signals. The coding system utilizes nested lattice codes for the transform coefficients and exploits side information at the decoder. In addition, a disparity analysis of the first image pair of the sequences is performed at the decoder. The efficiency of the decoder is improved by disparity compensation of one video signal at the decoder. When compared to decoding without side information, decoding of the quantized transform coefficients with side information reduces bit-rate. Additional bit-rate savings can be obtained with disparity compensation at the decoder and decoding of transform coefficients with side information. Further, we address the theoretical problem of distributed coding of video signals in the presence of correlated video side information. The correlated video signals are disparity compensated and originate from cameras that monitor the same scene from different view points. We utilize a motion-compensated spatiotemporal transform to decorrelate the video signals. One camera signal will provide the disparity-compensated side information to improve the coding of the second camera signal. We derive the optimal motion-compensated spatiotemporal t..