【作者】 徐谦；

【导师】 张洁；

【作者基本信息】 西南交通大学 ， 测试计量技术及仪器， 2010， 硕士

【摘要】 条形码是一种用印刷图形实现快速计算机输入的技术。通过它可以代替手工录入,降低录入差错,加快人员或商品的流通效率,改善人们的生活。随着电子技术的飞速发展,数字图像处理在人们日常生活中的使用已经越来越普及,在证件条码识别、公安、交通监控、火灾监控、产品识别、防伪等领域都有了广泛的应用。本设计就是基于数字图像处理的数据采集方案,即通过COMS图像传感器采集一维条码、二维条码图像数据信息,将其无损传递到PC机,由PC机对采集到的信息进行运算解码,输出采集码字的详细信息。该产品在国外已经广泛使用,在国内的市场也在不断拓展。身份证、护照、名片以及书籍、消费品等商品上具有的一维条码、二维条码,可经该设备送PC机解码后查询数据库,以鉴别真伪,保护广大群众的切身利益。相对于欧美等相似产品而言,该设计方案不仅成本低,而且由于传输过程的巧妙控制,使其具有广泛的应用前景。在本论文的研究课题中,USB固件驱动Micron公司的MT9M112图像传感器取得图像信息,数据在经FPGA(Field Programmable Gate Array)缓冲后用USB (Universal Serial Bus)传输至PC机,供后者解码后进行各种应用。方案利用FPGA的FIFO核(FIFO Core)资源不仅顺利解决了MT9M112和USB因工作频率不同而产生的速率匹配问题,而且将8位图像数据转换为16位,大大加快了数据的传输速率,使PC机得到的数据更加流畅,同时通过对USB(这里采用的是Cypress的EZ USB FX2)增强型51核控制,实现了对MT9M112的亮度、画质、防拖影、以及指示灯等的控制,提高了产品的适应性和识别率。更多还原

【Abstract】 Bar-code is a technology for printed figures to act as a fast input way to computer. It can replace manual keyboard typing in many fields, thus decrease the possibility of wrong typing, speed-up the flow efficiency of people and goods, and make life better. With the rapid development of electronics technology, digital image processing has being applied in people’s daily lives, now the use of it has become more and more popular in the bard-code recognition domain, public security, traffic control, fire control and so on. This design is based on digital image processing of data transformation, in which a CMOS image sensor captures a frame of one dimensional or two dimensional bar-code as image data, then transfer it to a PC. The PC would decode the image data and output the number and characters which the bard-code expresses. The product has been widely used abroad and in the domestic market it is expanding.It can be used for identity cards, passports, business cards, books, supermarket products and so on. By PC and the associated databases, the decoded information can be used to identify the authenticity and protect the vital interests of the people. Compared to the similar products manufactured by Europe and the United States, this design not only has lower costs, but also does well in controlling images’transmission. As a result, the decoding process has been accelerated dramatically; it is competitive in the market of bar-code recognition products.In this study, the principle of the USB firmware is driving MT9M112, the image sensor presented by Micron, to capture image data and send it to a FPGA (Field Programmable Gate Array) chip, then the data would be transferred to a PC via USB (Universal Serial Bus), get ready for bar-code recognition. The use of the FPGA’s program FIFO (or "FIFO Core") core resources not only solve the problem of different operating data rate successfully between MT9M112 and USB interface, but also change the 8-bit image data into 16-bit format, which greatly improves transfer performance. So the PC would get data more fluently. At the same time by taking advantage of the enhanced features of the 51-core offered by Cypress’s EZ_USB FX2, we are able to control the MT9M112 brightness, picture quality, as well as light control of the device, etc. In addition, the product is so considerate to facilitate users’operation during our design that we are sure it would be easily accepted by consumers.更多还原