近年來，越來越多手持裝置採用Android為作業系統，由於其開放的特性，讓開發者有很大的研發空間，面對需求越來越大的多媒體播放能力，其OpenCORE多媒體框架更提供了開發的基礎。
此外，為了加強多媒體處理的能力，許多平台會利用DSP加強影像處理的效能。對於手持裝置這類以電池驅動的產品來說，省電一直是很多人探討的議題，面對這個難題，若能導入DVFS(Dynamic Voltage and Frequency Scaling)的機制，視處理器的負載調整合適的電壓及頻率，將可以節省許多電能，進而延長電池的壽命，也讓產品在市場上更有競爭力。
本文以PAC Duo SoC異質多核心平台為基礎，於Android作業系統的OpenCORE多媒體框架下增加對Dual DSP H.264解碼的支援，並針對其解碼流程與特性設計了一套DVFS機制，最後驗證及分析此套機制在平行影像解碼之省電效果。

In recent years, more and more mobile devices choose Android as their OS. Because of this open source project, developers get a free environment to do anything. Moreover, to meet the growing requirement for multimedia playback, Android’s OpenCORE multimedia framework also provides a great base for development.
In addition, to deal with multimedia processing, some mobile devices may contain DSP to enhance performance. For such kinds of battery-driven devices, power saving is always an interesting issue. In this case, if we can integrate DVFS (Dynamic Voltage and Frequency Scaling) with video decoding to dynamically adjust suitable voltage and frequency according to processor’s loading, more energy could be saved. Thus the battery can come with better performance and make the product more competitive.
This thesis first describes how to add support for Dual DSP H.264 decoding for Android OpenCORE on heterogeneous multicore platform PAC Duo SoC. Then it proposes a DVFS mechanism for the decoding flow according to its characteristics, verifies and analyzes this mechanism for its performance on energy reduction on parallel video decoding.

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