How Optimal Is Algebraic Binning Approach: A Case Study of the Turbo-Binning Scheme With Uniform and Nonuniform Sources

This paper investigates the optimality of the binning approach in distributed source coding for both uniform and nonuniform sources. While the algebraic binning scheme is optimal for uniform sources both asymptotically and at finite lengths, it is shown that the optimality holds only asymptotically for nonuniform sources. Highperformance turbo codes are used with the binning scheme on several source distributions to quantify how close they can get to the theoretical limit with relatively large block sizes. For nonuniform sources, optimal code design and variable-length bin-indexes are exploited as a useful extension to the conventional binning scheme. It is shown that the two strategies combined can improve the compression rate by as much as 0.22 bit/symbol for highly biased sources.