目 录
摘 要 ........................................................................................................................I
ABSTRACT ..................................................................................................................II
1 前言............................................................................................................................1
1.1 研究背景及意义 ........................................................................................................1
1.2 车牌识别系统国内外研究现状.................................................................................1
1.3 中国车牌特征 ............................................................................................................2
1.4 研究内容 ....................................................................................................................3
2 系统硬件设计............................................................................................................4
2.1 系统总体设计 ............................................................................................................4
2.2 最小系统设计 ............................................................................................................4
2.2.1 处理器介绍 .....................................................................................................4
2.2.2 最小系统电路设计 .........................................................................................6
2.3 下载仿真电路 ............................................................................................................7
2.4 摄像头 ........................................................................................................................8
2.4.1 OV2640 介绍 ....................................................................................................8
2.4.2 SCCB 协议 .........................................................................................................8
2.4.3 FIFO ...................................................................................................................8
2.4.4 DMA ..................................................................................................................9
2.4.5 DCMI 接口 ........................................................................................................9
2.5 LCD 显示电路 ............................................................................................................10
2.5.1 TFT-LCD ...........................................................................................................10
2.5.2 FSMC ...............................................................................................................10
2.6 SD 卡接口电路 ..........................................................................................................12
2.7 GPRS 通信模块..........................................................................................................13
3 车牌识别算法研究..................................................................................................14
3.1 BMP 图片基本知识...................................................................................................14
3.1.1 BMP 文件格式................................................................................................14
3.1.2 RGB 颜色模型.................................................................................................15
3.2 车牌图像预处理 ......................................................................................................16
3.2.1 车牌图像灰度化 ...........................................................................................16
3.2.2 灰度变换 .......................................................................................................16
3.2.3 图像平滑处理 ...............................................................................................17