【作者】 刘斌；

【导师】 李仲阳；

【作者基本信息】 湖南师范大学 ， 电路与系统， 2005， 硕士

【摘要】 数字信号处理器(DSP)作为一种新型的专用于数字信号处理领域的微处理器,其独特的硬件结构特别适合于数字信号处理领域,被人们大量地使用在各种便携式、实时数字信号处理场合。目前DSP是数字信号处理领域中最有效的处理工具之一。 本文首先介绍了DSP的结构特点、演化,然后在详细分析TMS320VC5416结构特点的基础上,对TMS320VC5416为核心构建的数字图像压缩处理平台进行了探讨,系统地讨论了DSP硬件平台中的DSP系统电路设计、液晶控制电路设计、外围电路接口程序设计。 文章针对JPEG压缩算法中运算量最大的DCT变换提出了一种新的计算方法。改进的DCT计算方法具有较好的算法结构,能充分利用DSP的硬件结构和DSP的指令特点。实现的图像压缩算法可以满足低速率条件下对于电视图像信号的压缩处理。文章还从减少系统开销的角度分析了如何对程序的DSP实现进行优化。 图像压缩是减小图像数据量,方便进行图像的传输、存储和处理的有效手段,图像实时压缩是进行图像实时处理的基础,研究图像压缩的实时实现有重要的意义。 为尽可能地满足便携式实时处理系统的要求,系统设计当中,采用了以下几种方法:(1)硬件电路采用多电源供电、低电压复位、增加检测电路等:(2)采用多层PCB设计,减小了系统体积也保证系统的稳定性;(3)按照软件工程的要求进行系统分析,规划系统框图、流程分析、模块划分,减小了不同模块的相关性,从而最大限度避免了错误的发生;(4)采用新的DCT计算方法满足对图像压缩的时间要求。更多还原

【Abstract】 As a new microprocessor with special hardware structure, DSP is one of the most effective tools used in many real-time processing and portable processing applications. This paper’discusses the design and realization of an image compress system based on TMS320VC5416.Image compressing can reduce image data and convieniently process image by transfer, storage and processing. It is important to realize a real-time image compress system.First of all, the history and hardware characteristic of DSP were introduced. Then based on analysis for the hardware characteristic of the chip TMS320VC5416, an image compression platform is proposed. Design of the DSP system circuit, LCD control circuit and the peripheral equipment circuits are discussed too.As follows, the paper brings up a new calculation method about DCT, which is the most operation part in JPEG, New calculate method has good arithmetic structure, as it well utilizes DSP hardware structure. With the new DCT calculate method, DSP can real-timely compress TV image with lower bits ratio. We also analyzed how to improve programming to reduce system cost.Software and hardware measures are both adopted to meet requires of portable and real-time systems, which are process speed and small system bulk. Fisrst ,we used multi-power source to supply system power, low voltage reset, watch circuit. Secondly, we used multi-PCB board, which leads to compact and more steady. Thirdly, we followed methods of software engineering requires such as systems analysis, flow chart analysis and modularization. At last, a new DCT calculate menthod ensures image compress system to meet time require of our applications.Based on the new DCT cacluation method and the hardware platform, an iamge compression system is realized. Through test, it proves that the system can the be well used in portable and real-time更多还原