Android系統是Google為了踏入智慧型手機產業所提供一個開放式軟體平台，近年來，越來越多智慧型手機裝置採用Android為作業系統，代表Android系統的功能特性，已滿足部分人們生活上的需求，使其開放原始碼的特性，也讓開發者有很大的研究發展空間，尤其現在應用於其他非手持裝置產品的嵌入式系統，也漸漸地使用Android系統做為軟體開發的核心。

有別於一般Linux系統架構，Android系統把各個軟體層次結構:如核心層、應用層以及Android系統特有中介軟體層(Middleware)的部份，因此有些硬體平台只支援一般Linux系統架構可能無法展現Android系統特有功能，所以本文選用Hi3515為主要硬體核心架構所組成的嵌入式DVR(Digital Video Recorder)系統，在此DVR平台軟體架構只能支援一般的Linux Kernel系統和硬體核心架構的限制情形下，可能無法納入Android系統內部軟體架構裡所有層次，因此本文在Android系統軟體架構核心(Kernel)程式找出與一般Linux系統核心程式不同之處，做比較與分析該兩者核心程式看有多少功能上差異，然後進行修改程式把Android系統核心部份程式移植到一般Linux Kernel系統裡面，並且執行編譯程式，完成Android核心程式移植到一般Linux核心程式實作。

最後本文將上述兩者核心系統裡面的應用層，建立同樣多媒體應用程式，使DVR具有錄影(REC)跟回放(Playback)的功能，然後在具有Android核心系統的多媒體應用程式中，加入Ashmem功能，同時也將利用Linux系統top指令工具，來分析兩者不同核心系統的整體效能，因此得到分析結論是Android核心系統比一般的Linux系統可節省5%~10%整體系統效能，且維持DVR系統穩定性。

Google builds its smart phone industry by providing an open software platform, Android. Recently, more and more smart phones take Android as their operating system. Android smart phones help people to meet their daily communication and information needs. Being an open source operating system, Android gives developers a great space for research and development. Particularly, Android now is not only used in handheld devices, but also some non-embedded systems.

Unlike ordinary Linux system architecture, Android's architecture is divided into several levels such as the core layer, application layer, middleware layer, and Android system-specific part. So some common hardware platform supporting Linux system may not easily support Android system-specific features. Therefore, we use an embedded DVR (Digital Video Recorder) system with Hi3515 as our main hardware. This DVR architecture easily supports Linux Kernel, but it does not trivially support Android software architecture. This article is to find the differences between Linux, Android, the embedded DVR, and to port Android Kernel onto the embedded DVR.

Finally, for the ported Android and a general Linux Kernel, we build the same multimedia applications, so that the DVR can playback the video, and we also add Ashmem function. We use the Linux system top command tool After analyzing overall performance of two systems, we get a conclusion that the ported Android system is stable and has 5%~10% better performance than the general Linux Kernel.

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