基于嵌入式系统的视频编解码与传输技术研究

发布时间：2018-04-24 22:06

本文选题：FPGA + 图像采集　；参考：《南京理工大学》2017年硕士论文

【摘要】：数字时代,社会的安全离不开监控技术发展。无论是十字路口的电子眼还是校舍走廊中的监控探头,还是基地中的雷达设备,随着设备精度的不断提高,随之而来的就是数据量的增加。这时,如果有一个压缩率高,损失小或无损的高速压缩算法加入系统,将会极大减少系统中传输与存储模块的压力。本文以压缩算法为核心,主要围绕有损压缩的硬件化实现与嵌入式系统的无损压缩展开论述,具体内容包括:1)基于FPGA的MJPEG视频采集压缩模块。本文主要研究了某预研项目中无人机的视频采集以及编码模块的硬件化实现,包括CMOS摄像头的视频采集,VGA信号转换与输出,IMJPEG硬件化压缩,上位机和与其通信的接口模块设计。同时本文基于CMOS摄像头的性质,提出了一种基于K-MEANS的图像增强算法,用于增强采集到的图像数据,解决了在低照度环境下的图像采集问题。2)雷达终端的嵌入式雷达视频压缩算法。本文也将压缩算法运用在雷达终端的雷达视频记录上,由于雷达视频要求精度高,所以采用了无损压缩的LZW压缩编码方式。本文也提出了一种改进的LZW算法,在保证没有误编码的前提下使用变长的字典编码方式,提升了压缩率。
[Abstract]:In the digital age, social security can not be separated from the development of monitoring technology. Whether it is the electronic eye at the crossroads, the surveillance probe in the corridor of the school building, or the radar equipment in the base, with the continuous improvement of the precision of the equipment, the amount of data will increase. In this case, if a high-speed compression algorithm with high compression ratio and little or no loss is added to the system, the pressure of the transmission and storage modules in the system will be greatly reduced. This paper focuses on the compression algorithm and discusses the hardware implementation of lossy compression and the lossless compression of embedded system, including the MJPEG video capture and compression module based on FPGA. This paper mainly studies the hardware realization of video acquisition and coding module of UAV in a pre-research project, including the conversion of CMOS camera video acquisition and the hardware compression of output IMJPEG, the design of upper computer and interface module of communication with UAV. At the same time, based on the nature of CMOS camera, this paper proposes an image enhancement algorithm based on K-MEANS, which is used to enhance the collected image data. The problem of image acquisition in low illumination environment. 2) the embedded radar video compression algorithm of radar terminal is solved. In this paper, the compression algorithm is also applied to radar video recording at the radar terminal. Because of the high accuracy of radar video, lossless compression LZW compression coding method is adopted. In this paper, an improved LZW algorithm is also proposed, which can improve the compression ratio by using a variable length dictionary coding method without miscoding.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN919.81

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