【作者】 宇鹏；

【导师】 齐文新；

【作者基本信息】 华中科技大学 ， 模式识别与智能系统， 2009， 硕士

【摘要】 视频监控具有广泛的应用,同时随着技术的进步人们对监控提出了新需求。无线远程监控系统是在传统测控系统的基础上结合当前无线通信技术和信息处理技术而发展起来的新型远程监控系统。它为人们远程监控现场提供了极大的方便。然而现有的无线视频监控系统,虽然能够实现现场的实时监控、视频流编码和无线传输等功能,但普遍都存在下面几个问题:(1)视频压缩比低;(2)图像清晰度较差(3)处理速度低,监控路数少。在无线视频监控中,由于无线传输速度的限制,需要在尽可能低的码率下获得尽可能好的图像质量,这就要求采用高效率的视频编解码算法。现有系统一般采用如MPEG-4的编码算法,并不能满足无线视频系统的特定要求,在传输宽带固定的情况下为了保证视频的连续性,只能降低码流,从而造成清晰度较差的问题。针对上述问题,本论文设计了结合最新数字视频编码标准H.264和CDMA2001X数据传输技术的基于CDMA的嵌入式视频监控系统。系统以专用的视频芯片GM8180为核心,实现了可多达8路的现场实时监控,并通过无线CDMA网络把H.264压缩的视频流传输到中心服务器端,实现了低码高清的传输目的。本文设计了基于CDMA的嵌入式视频监控系统的终端硬件。该终端硬件以RS-232接口和CDMA模块连接,实现了H.264视频流数据的无线传输;实现了GM8180平台上Linux内核操作系统的裁剪和移植以及Bootloader的移植,并给出具体的操作流程;实现了本系统视频流数据的采集、压缩和传输的软件部分。更多还原

【Abstract】 There is a wide range of applications in video surveillance, and people has new demand for the video surveillance with the technological progress. Wireless remote monitoring system is a new type of remote monitoring system based on traditional measurement and control system and is a combination of the current wireless communications technology and information processing technology. It provides a great convenience for people to remote monitoring.However, the existing wireless video surveillance system can achieve the real-time monitoring, video streaming encoding and wireless transmission. But generally there are the following issues: (1) video compression ratio is low; (2) image resolution poor (3) low processing speed, less monitoring approach. In wireless video surveillance, because of the speed of wireless transmission constraints, it need to get the best possible image quality under the rate as low as possible. This means the system requires highly efficient video codec algorithm, while the existing system use the encoding algorithm such as MPEG-4 which can not meet the specific requirements in the transmission. So in order to ensure the continuity of the video, it have to reduce the bit stream to result the problem of poor definition.According to these problems, this paper designs a CDMA-based embedded video monitoring system combined with the latest Digital video coding standard H.264 and data transfer technology CDMA2001X . The system is designed to make a dedicated video chip GM8180 as the core to realize up to 8 real-time monitoring . And it can transmit H.264 compressed video streams to the central server side through the wireless CDMA network. It realizes the purpose of low-key high-definition transmission.The paper designs a CDMA-based embedded video monitoring system terminal hardware. This terminal hardware connect the CDMA modules through RS-232 interface to achieve the wireless transmission of data; it realizes the cutting and transplantation of Linux operating system and Bootloader on the GM8180 platform and the specific operational procedures; it also realizes software of video stream’s data collection ,compression and transmission.更多还原