Android图形显示硬件加速和音频系统的研究与移植

发布时间：2018-10-31 20:37

【摘要】：Android系统是一种嵌入式的多媒体系统。随着多媒体技术的发展,图像处理所需要的计算量越来越大,仅依靠一颗通用的CPU来完成复杂繁多的图像处理计算,越来越困难。常用的DSP微处理器和Intel处理器扩展指令集方式的显示硬件加速技术不能在嵌入式硬件平台实现,要减少嵌入式CPU处理图像数据的负担,需要使用CPU平台的2D或3D模块来实现显示硬件加速。同时,音频系统也因为没有统一的音频硬件,不同的平台设备所使用的编解码芯片,处理器音频处理模块各不相同,在跨平台的时候,都需要开发者来完成软件的移植。针对上述问题,本文以使用的R2R(SH-MobileR2R,瑞萨SH7724处理器)硬件平台为对象,研究分析了Android的显示系统和音频系统；解决的问题是在R2R硬件平台上实现多硬件模块协同加速图像显示,以及音频系统的移植。本文主要工作如下： 1)结合Android系统堆栈层次的特点,自上层向下层的研究了Android多媒体的显示系统,针对R2R硬件平台的2D硬件模块的功能特点,结合Android显示系统的架构,设计了多硬件模块协同加速图像显示的方案； 2)采用从底层向顶层移植的思路,移植BEU(混合引擎)、2DDMAC(图像获取直接存储器)硬件模块驱动,硬件适配层。实现了Android显示系统的硬件加速功能； 3)研究了Android音频系统的硬件结构和软件架构,结合R2R硬件平台的特点,设计了R2R硬件平台的音频移植方案,使音频系统支持多采样率音频文件播放,移植了音频驱动和硬件适配层,实现了音频系统功能。经过以上的移植,在R2R硬件平台实现了Android系统多硬件模块协同加速图像显示,提升了Android界面滑动的流畅度；实现了Android音频系统在R2R硬件平台上的移植,支持多采样率音频文件播放,成功使用Android应用程序播放音频文件,通过移植前后对比分析,系统性能得到提升。
[Abstract]:Android system is an embedded multimedia system. With the development of multimedia technology, image processing needs more and more computation. It is more and more difficult to rely on a general CPU to complete the complicated and various image processing calculation. The commonly used DSP microprocessor and Intel processor extended instruction set display hardware acceleration technology can not be implemented on embedded hardware platform, so the burden of embedded CPU processing image data should be reduced. Need to use CPU platform 2 D or 3 D module to achieve display hardware acceleration. At the same time, the audio system also because there is no unified audio hardware, different platform devices used by the codec chip, processor audio processing modules are different, in cross-platform time, developers are required to complete the software migration. Aiming at the above problems, this paper takes the R2R (SH-MobileR2R, Resa SH7724 processor) hardware platform as the object, studies and analyzes the display system and audio system of Android. The problem is to realize multi-hardware module cooperative acceleration of image display and transplant audio system on R2R hardware platform. The main work of this paper is as follows: 1) according to the characteristics of Android system stack layer, the Android multimedia display system is studied from the upper layer down layer. According to the function characteristics of 2D hardware module of R2R hardware platform and the framework of Android display system, The scheme of multi-hardware module cooperative acceleration image display is designed. 2) using the idea of transplanting from the bottom layer to the top layer, transplanting BEU (hybrid engine), 2DDMAC (image acquisition direct memory) hardware module driver, hardware adaptation layer. The hardware acceleration function of Android display system is realized. 3) the hardware structure and software architecture of Android audio system are studied. According to the characteristics of R2R hardware platform, the audio transplant scheme of R2R hardware platform is designed, which enables the audio system to support multi-sampling rate audio file playback. The audio driver and hardware adaptation layer are transplanted to realize the function of audio system. After the above transplantation, the multi-hardware module of Android system can accelerate the image display cooperatively on the R2R hardware platform, which improves the smooth degree of Android interface sliding. The transplant of Android audio system on R2R hardware platform is realized, and the multi-sampling rate audio file playing is supported. The Android application is successfully used to play the audio file. The system performance is improved by comparing and analyzing before and after transplantation.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TP368.1;TP37

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