FPGA implementation of full-search vector quantization based on partial distance search

This paper presents a novel algorithm for field programmable gate array (FPGA) realization of vector quantizer (VQ) encoders using partial distance search (PDS). In most applications, the PDS is adopted as a software approach for attaining moderate codeword search acceleration. In this paper, a novel PDS algorithm well suited for hardware realization is proposed. The algorithm employs subspace search, bitplane reduction, and multiple-coefficient accumulation techniques for the effective reduction of the area complexity and computation latency. Concurrent encoding of different input vectors for further computation acceleration is also allowed by the employment of multiple-module PDS. The proposed implementation has been embedded in a softcore CPU for physical performance measurement. Experimental results show that the implementation provides a cost-effective solution to the FPGA realization of VQ encoding systems where both high throughput and high fidelity are desired.