Development of a Functional LSI Achieving Low-rate Multimedia Data Transmission.

本研究计画的主要目的是发展一个包含低功率系统的多媒体通讯系统，此系统是为即时低速率影像压缩与解压缩而开发。(1)一种使用矢量量化的低速率视频压缩算法：FRMSHVQ FRMSHVQ代表固定速率多级分层矢量量化。它可以压缩10 fps。Q-CIF（176×144）视频序列到29.2kbps。FRMSHVQ使用矢量量化代替MPEG上的DCT，与MPEG上的IDCT操作相比，该特征通过使用表查找而使得容易解压缩。(2)用于FRMSHVQ的低功耗DSP：VP-DSP是一种矢量流水线DSP，它的寄存器文件中包含多个长位（160位）寄存器，用于FRMSHVQ中常用的16个并行SIMD操作。所实现的大规模集成电路在25 MHz和1.6V电压下工作正常，真实的功耗仅为49 mW。时间编码/解码10 fps。QCIF视频序列。

The main goal of this research project is to develop a multimedia communication system including low-power system-LSIs that are developed for real-time low-rate image compression and decompression.This research develops two innovative results as follows.(1) A Low-rate Video Compression Algorithm using Vector-Quantization : FRMSHVQ FRMSHVQ stands for fixed-rate multistage Hierarchical Vector Quantization. It can compress a 10fps. Q-CIF (176×144) video sequence to 29.2kbps. FRMSHVQ uses vector quantization instead of DCT on MPEG which feature enables easy decompression by using a table look-up compared with IDCT operation on MPEG.(2) A Low-power DSP for FRMSHVQ : VP-DSP We have developed and implemented a low-power DSP for the FRMSHVQ algorithm called VP-DSP.VP-DSP stands for a vector-pipeline DSP.The register file of VP-DSP contains several long-bit (160-bit) registers for 16-parallel SIMD operations frequently used on FRMSHVQ.The implemented LSI works properly at 25MHz and 1.6V.The power dissipation is only 49mW for real-time encoding/decoding of a 10fps. QCIF video sequence.