Power reduction of MPEG video decoding for mobile multimedia systems

Graduation date: 2008The purpose of this thesis is to explore methods which can reduce the power\ud dissipation of a mobile system while decoding MPEG video. MPEG decoding is a\ud microprocessor intensive process that makes heavy use of both the L1 and L2 caches\ud as well as main memory. The heavy load placed on the system during the MPEG\ud decoding process results in large dynamic power losses caused by both the execution\ud of instructions and the flow of data into and out of the caches and main memory.\ud To reduce the power dissipation of the system during MPEG decoding, multiple\ud techniques were applied to control the flow of data and make the decoding process\ud more efficient. The system was simulated with different L2 cache sizes to determine\ud which sizes resulted in the best power improvements while maintaining acceptable\ud performance levels. A fast IDCT algorithm was implemented to improve the\ud efficiency of the decoder during the computationally heavy IDCT phases. Finally,\ud selective caching was introduced to the system to further reduce the traffic between\ud the caches and main memory. These techniques were simulated on the Sim-Panalyzer\ud simulator using a similar system configuration to one found in a typical mobile media\ud device. These methods coupled with proper L2 cache sizing produced power\ud reductions of 50-60% over the baseline system