The goal of this research is to study complexity issues, develop algorithms, and perform experiments with adaptive data compression algorithms, both lossless and lossy. The work proposed will build on our previous and current research and will have a continued "theme" of a blend of theoretical and experimental work. The term "high performance" has been used in the proposal title to indicate we are interested in algorithms that both compress well and can be implemented to run in real time in high bandwidth applications. The areas of research proposed are: * Error resilience; * Optimizations for one-dimensional lossless compression; * 2-D lossless compression; * Adaptive VQ; * Real-time video compression employing off-line learning; * Parallel algorithms for adaptive compression; * Automated browsing.