Comparisons of fast 2D-DCT algorithms for parallel programmabledigital signal processors

摘要

Recent advances in technology make it possible to integratemultiple processors into a single chip to build high performanceparallel programmable digital signal processors (PPDSPs). Theseprocessors are expected to replace many dedicated digital signalprocessors to implement important image/signal processing algorithmssuch as discrete cosine transform (DCT). The paper addresses the issueof how to compare fast 2D-DCT algorithms when they are implemented on aPPDSP. Previously, the efficiency of these algorithms is compared basedon the number of operations. This comparison is reasonable when thesealgorithms are implemented on a dedicated DSP. However, this comparisonmay not be suitable for general-purpose PPDSPs. The paper proposes touse three parameters, the number of data accesses, the number ofcommunications, and the distance of communications, as new criterion forperformance comparison of DCT algorithms. An algorithm-level techniqueis developed to estimate these parameters for DCT algorithms. Thecomparison results based on the parameters show that the algorithmproposed by Cho and Lee (1991) might be the best choice for a PPDSPunless it requires large overhead for communication between remoteprocessors. In this case, the conventional row-column method with a fast1D-DCT algorithm might be the most efficient