Energy-optimized lossless compression: Rate-variability tradeoff

We pose the problem of energy-optimized lossless compression and analyze a simple compression framework in which energy consumption is given by a weighted sum of two components, respectively proportional to the compression rate and to the average number of bit flips that occur in a certain hardware register. The latter component, which we term variability, is meant to serve as a proxy for the energy consumption of the computations underlying the compression step. Our results include bounds on the rate-variability tradeoff for symbol-wise compression of discrete memoryless sources and a characterization of the asymptotically optimum tradeoff between rate and variability for block-wise compression.