基于嵌入式平台的图像采集与处理系统的研究/The design of image gathering and processing system based o

2018-12-27 06:38:00

DSP design 图像 image processing



图像技术和嵌入式技术被广泛应用于许多领域。本文介绍了一种基于嵌入式平台的集采集、存储、传输和处理于一体的图像采集与处理系统,并阐述了该系统的硬件电路和软件程序的设计。由于该系统结构简单,功能完善,应用灵活,因此在实际工程应用中具有一定的参考价值。
本文从图像采集与处理技术的原理出发,首先介绍了在系统的设计中所要应用到的关于图像的各种基本知识,接下来,就系统的结构作了整体的概述,包括系统的工作原理与功能,系统的软件平台以及系统的核心器件的选择。根据系统的结构组成和功能特点,本文将系统划分成了两大模块来分别进行阐述:图像采集与存储模块和图像传输与处理模块。
对于图像采集和存储模块,本文首先阐述了模块的硬件部分:包括图像解码芯片,可编程逻辑器件CPLD和双口RAM的硬件电路的设计;在软件部分,首先讨论了如何通过数字信号处理器DSP完成图像解码芯片的初始化以使得图像解码芯片能够完成图像的数字化,由于DSP的片内存储空间的限制而对图像数据不能全部采集,因此接下来对系统需要采集的图像的容量以及采集的时序作了详细的介绍,在模块设计的最后,阐述了如何应用CPLD来实现图像的采集与存储的时序并通过MaxPlusⅡ对时序进行仿真与调试。
在图像的传输与处理部分,首先讨论了图像传输与处理模块的硬件设计:包括数字信号处理器DSP,双口RAM和外扩Flash的硬件电路的设计。由于图像的传输是图像的采集和图像的处理之间的桥梁,本文紧接着阐述了图像传输的方法:系统在设计中采用DSP的DMA传输方式将图像数据从片外双口RAM传输至片内RAM。对于图像的处理,由于图像的预处理往往是图像处理的第一个步骤,因此系统对采集到的图像数据做了中值滤波和Roberts边缘检测的预处理并通过DSP的软件平台CCS观察了图像的画面。在模块设计的最后,对DSP的最小系统的设计即DSP和外扩Flash的接口电路设计以及DSP的Bootloader作了详细的介绍。
最后,对本系统设计和研究的成果进行了总结并对嵌入式图像采集和处理技术的未来发展趋势做了展望。



The image technology and the embedded technology are widely applied in many fields. The design introduced an image gathering and processing system included gathering, saving, transmission and processing based on embedded platform, and illustrated the system hardware and software design. The system is simple, integrated, flexible, real-timed, so it has reference value in the project application.
The design begins with image gathering and processing principle, introduced some basic knowledge about the image application in the system, then summarized the system framework, included function principle, software platform and the choice about the system core component. According to the system structure and the function characteristic, the design divided the system into two modules: image gathering and saving module and image transmission and processing module.
To the image gathering and saving module, the design gived the proposal to the hardware department first: the hardware constituted with image decoded chip, CPLD and dual-port RAM. In the software department, at first discussed how to initialize the image decoded chip by the DSP so that system can finish the image digitization. Because of the limit of the DSP memory space, the image data can’t be gathered completely, then introduced the image gathering capability and succession. At the last, illustrated how to realize and simulate the succession by the CPLD and MaxPlusⅡ.
In the image transmission and processing department, at first discussed the module hardware composition: included DSP, dual-port RAM and Flash. Because the image transmission is the bridge between image gathering and image processing, then the design illustrated the image transmission method: used DMA on the DSP to transmit the image data from external dual-port RAM to internal space. To the image process, the image pre-processing is the first step to the image processing, so the system processed the image data with Median-filter and Roberts edge-detection, and observed the image by the CCS2.0, at the last, introduced the DSP smallest-system design included interface design with Flash and Bootloader.
At the end, make a conclusion to the design and make an expectation to the development of the embedded system.