The FPGA Design Of Image Recognition System For The Hand-held Meter Reading Instrument

To avoid various disadvantages of the manual methods for recording and charging management the electronic company,in this paper,we design an image recognition system in the background of the research of meter reading instrument.The system is based on Machine Vision technology,providing a new method for meter reading.The core of the image recognition system is how to make accurate and effective identification from the acquired digital images. Generally,there are two steps to complete the work,that is,image pre-processing and digital character recognition.The main purpose of image pre-processing,which filters out noise and keeps and highlights the part of reflecting essential characteristics of the image,is to acquire image information effectively by smaller cost.According to the trait of acquired images,this paper used methods of median filtering,edge detection and binarization to make image preprocessing.Kinds of image processing algorithms are compared,selected,designed and hardware implemented,which provides a basis and protection for digital character recognition.Digital Character Recognition is the main goal of the system,which automatically identify the pre-processed image.This paper introduces the general steps of Digital Character Recognition.In accordance with the steps we located and splited characters of the images with Projection Method,and thin the characters.According to the characteristics of meter dial characters,in this paper,we proposed a new recognition algorithm for printed digital character. The algorithm recognized digital Character using the structural characteristics of straight line and endpoint,which can rapidly recognize a digital image with accuracy guarantee.This paper presents the hardware design of image recognition system by using Verilog Hardware Description Language programe.Function Simulation of the design has been done by using Mentor Modelsim simulator.By adopting Synplify tool,this paper implements the logic synthesis for the design.With the meter images collected for testing,the results show that the system can meet performance requirements.