In this paper, we present a design of MPEG-4 video codec chip to reduce the power consumption using frame level clock gating, macro block level and motion estimation skip scheme. It performs 30 frames/s of codec (encoding and decoding) mode with quarter-common intermediate format (QCIF) at 27 MHz. Power consumption is 290 mW at 27 MHz operation, which is achieving 35% power saving compared to a conventional CMOS. Motion Estimation skip method is employed to reduce 32% computation load. This chip performs MPEG-4 Simple Profile Level 2 (Simple@L2) and H. 263 base mode. Its contains 388,885 gates, 662 k bits memory, and the chip size was 9.7 mm9.7 mm which was fabricated using 0.35 micron 3-layers metal CMOS technology.

In this paper, we present a simple codeword length generation algorithm and its hardware implementation. The proposed technique is based on the dividing the Huffman table as two parts; with leading 0'bits and following bits. The method is shown to be efficient in the memory requirement and searching speed since only logic gates are needed in the implementation and searching can be process parallel without looking up the memory table. The total equivalent gates for the implementation are about only 100 gates and critical path delay is 10 ns. The results of experiments show that the proposed algorithm has a very high speed and a good performance. The designed blocks are synthesized by Compass synthesis with 0.5 µm CMOS, 3.3V, technology.