【作者】 陈义钦；

【导师】 覃团发；

【作者基本信息】 广西大学 ， 计算机应用技术， 2007， 硕士

【摘要】 近年来，随着多媒体技术及无线传输技术的发展，基于嵌入式流媒体技术的视频采集传输系统作为远程视频监控、可视电话会议和工业自动控制领域的一项核心关键技术得到了飞速的发展。因此研究在嵌入式平台上实现国际上流行的视频编解码技术、流媒体传输技术将有着广阔的应用前景和巨大的社会效益及经济效益。本文以一个实际的嵌入式视频监控系统开发为背景，对嵌入式系统实现的关键技术，嵌入式硬件平台的选型及嵌入式视频监控服务器端的软件系统设计及实现方法都进行了重点研究。通过研究国际上流行的嵌入式流媒体通信系统结构框架，结合本系统设计时所要求的性能指标，在硬件平台的选择上，基于freescale推出的ARM926EJ-S内核的i．MX处理器所具有的实时MPEG4和H．263编解码能力及其在多媒体应用上的诸多特点，因此我们选用i．MX21系列MC9328MX21VM微处理器作为系统硬件平台的核心部件；在软件平台上我们选用源代码开放的ARM Linux操作系统；在选择视频压缩标准时，通过相应的仿真测试分析，综合考虑压缩性能及运算量的因素，选用现阶段流行的MPEG4视频压缩标准；在多媒体数据传输协议上，我们选择了实时流媒体传输协议RTP／RTCP及RTSP。本文对设计裁减嵌入式ARM Linux内核及构建文件系统、设计移植图形用户界面、相关外围硬件设备在ARM Linux系统上驱动的开发均做了详细介绍，并就多媒体数据的采集、编码及传输模块在嵌入式系统中的实现做了重点研究，系统体系结构清晰，可方便地进行移植和扩展，利用本系统可实现无线视频监控，具有小型化，低功耗，稳定可靠等特点。更多还原

【Abstract】 In recent years, with the development of multimedia technique and wireless transmission technique, video capture and video transmission system based on embedded streaming technique is developing rapidly. This technique becomes a key technique in the field of remote video monitoring, video conference and industrial autocontrol. So it has extensive applications and great social and economic benefit to research the popular video coding-decoding technology and transmission technology of streaming media on embedded platforms.This paper takes the exploitation of a practical embedded video monitoring system as the background and studies the key techniques of embedded system. Besides, the type selection of embedded hardware platform, the design and the implementation of software system on embedded video monitoring server are studied in detail.This paper studies the popular structure frame of embedded streaming communication systems combining with the demanded specifications of the system. As the series of i.MX microprocessor based on freescale’s ARM926EJ-S^TM core is capable in real-time MPEG4 and H.263 coding-decoding and it has many advantages in multimedia applications,we have selected MC9328MX21VM microprocessor of i.MX21 as the key component of the hardware platform.Besides,we have selected the free software ARM Linux operating system as the software platform; After analyzing the simulation testing and taking into account both compressibility and computational cost, we have selected MPEG4 as the criterion of video compression; What’s more,we have selected the real-time streaming transport protocols RTP/RTCP and RTSP as the multimedia transport protocols.This paper introduces the design and reduction of the embedded ARM Linux core, the design and grafing of graphic user interface and the exploiting of the hardware equipment driver in ARM Linux system in detail. Specially, the implementation of multimedia data capture, coding and transmission in embedded system are studied in particular. The structure of system has good expansibility and clear framework. With this system, we can carry out wireless video monitoring, and the system is miniaturized, low power comsumed, reliable and stable.更多还原