隨著搭載ARM based的嵌入式系統裝置的應用，逐漸普及於我們的日常生活之中，視訊及多媒體的應用也成為嵌入式裝置不可或缺的規格，如影音串流、監控、工業自動化應用、車用系統..等，但由於嵌入式系統多要求裝置盡量小面積、輕巧、省電，以及多效能、少功耗的矛盾課題。本文即探討以搭載ARM技術的多核心處理器的嵌入式系統，在處理系統各種複雜的應用時如何來發揮系統的最佳效能和功耗。
由於ARM 處理器本身的算術邏輯單元ALU、暫存器等主要是為了32bit或64bit的運算來設計，在處理8 bit與16 bit的多媒體影像的像素資料及其顏色深度等的應用上，還是要搭配其所新增的NEON架構，使系統處理器不至於花費大量的時間在處理多媒體的資料，也使得裝置容易在效能與功耗之間取得平衡，達到整個嵌入式系統的多效能與少功耗的主要訴求。
因此在本實作中使用了ARM Cortex-A9雙核心處理器的嵌入式系統，也各自搭配了NEON的架構。測試平台的裝置運行的作業系統為Android 4.4 Kitkat 版本。實驗過程中利用JTAG 的除錯介面來控制嵌入式系統處理器核心的運作與否，以及適時地提供整體的效能與功耗分析。經由理論值、實作與驗證結果，可知在雙核心處理器與雙 NEON 功能啟動時，不論是在各個Benchmark的比較或是播放MPEG4、VP8及H.264等高解像度畫質的影片，都只有比單核心處理器多消耗約50% 的功率，但能提升約30% ~ 80% 以上的效能。多核心處理器的架構是可以明顯的彌補單核心處理器在處理複雜的應用時，僅多消耗少量的功耗，但可以發揮系統更佳的效能。

As the application of ARM based embedded system has become more common in our daily life, video and multimedia applications have also become necessary requirements for embedded systems, such as video streaming, surveillance, automobile systems, etc. Besides, embedded systems often require small form factor, light weight, low power, and multi-function features that are sometimes conflicting in nature.
This thesis discusses how ARM based embedded system can utilize the multi-core architecture, with the new NEON SIMD technology to maximize embedded system’s function and performance, as to improve the multimedia user’s visual experience. However, ARM CPU’s arithmetic logic unit (ALU) and register are mainly designed for 32 bit or 64 bit algorithm. If not used in conjunction with NEON architecture, the CPU will expend a lot of time on processing 8 bit and 16 bit multimedia’s video pixel data and respective color depth application, which will cause the device unable to achieve balance between performance and power consumption, and thus have adverse effect on the entire embedded system’s objective of multi-function and low power consumption.
In this test experiment, the embedded system is based on ARM Dual Cortex-A9 CPU with NEON , and the OS is Android 4.4 Kitkat. The JTAG debugging interface is used to control the operation of multi-core on and off. As the testing results of the implementation and verification, we can see that when the dual-core is on, whatever the benchmark test scores or playing high resolution videos, the system only consume about 50% of power, but can enhance more performance of about 30% to 80%. The multi-core architecture can significantly make up for the single core CPU in the processing of complex applications, and increase the embedded system functions more efficiency.

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