Introduction

This reference design implements a LPR(License Plate Recognition) system on DE1-SoC board. It receives video stream from D5M module connected to FPGA side, and runs algorithm processing function on Linux at hps side. Processed video stream will be output to FPGA VGA interface, and recognized license number will be printed to hps uart.

System Overview

Specification

• Implemented on DE1-SoC board. Video input from D5M module, 1024x768@25fps. Video output to VGA interface, 1024x768@60Hz.
• DDR3 on hps side, shared with FPGA.
• Hps runs Linux. Implement license plate recognition function with OpenCV support.
• Output recognition result on hps uart.
• Mark license plate in output video frame.

Develop Environment

• Quartus II Prime Standard 16.1, EDS 16.1
• Kernel version: linux-socfpga 4.1.22-ltsi; Rootfs: buildroot 2015.05
• Cmake 3.9.4, OpenCV 3.2.0, EasyPR 1.6.alpha
• DE1-SoC board, D5M module, TF card, VGA monitor

Qsys Interconnect

OpenCV Support

Our plate recognition application needs OpenCV library support. Follow below steps to port opencv-3.2.0 to hps:

• Download opencv source code from https://github.com/opencv/opencv/archive/3.2.0.zip
• Run "cmake-gui &" to configure opencv:

• Run "make" under opencv-3.2.0 path, generate arm-opencv library under /opt/arm-opencv-3.2.0 path

License Plate Recognition Application

• Based on open-source project EasyPR: https://github.com/liuruoze/EasyPR

Demonstration

• Unzip "easypr_de1soc_d5m.7z", and program the extracted easypr_de1soc_d5m.img to TF card

• Plug D5M module into GPIO1 extender of de1-soc board

• Set SW[9:0] to 10’b00_0000_00111

• Connect VGA output to monitor, and connect UART output to host PC
• Boot the board from TF card and login as "root"
• run ".\run_easypr.sh"

• Show vehicle plate photos on smartphone before D5M module

• Plate location will be marked in VGA output frames, and plate recognition result will be printed in UART output