基于BP神经网络的车型识别-外文翻译

一、外部资本材料license plate recognition based on prior knowledgeAbstract-In this paper，A new algorithm based on improved BP(back propagation，BP)neural network for Chinese vehicle license platewhat it remarkably differs from the tradiitional methods is the application of prior knowledge of license plate to the pr Ocedure of location，seethe layout of the Chinese VLP is an important feature，Which is used to construct a classifier for recognizing。the experiemental results show that the improved algorithm is effective under the condition that the license plates were degraded severely .index terms-license plate recognition，prior knowledge，vehicle license plates，neural network。I. INTRODUCTIONvehicle License-Plate(VLP)Recognition is a very interesting but difficult problem . it is important in a number of applications suchVLP recognition system conists of the plate location，the characters segmentation，And the characters recognition . these tasks become mome 5Reduce the complex and increase the recognition rate by using some specific features of local vlps and establishing some constrains on the the proposed algorithm overcomes the low speed Convergence of BP neural network8and remarkable increases the recognition rate especales二.specific features of Chinese vlpsA.Dimensionsaccording to The guideline for vehicle inspection9，All license plates must be rectangular And have The dimensions And have All 7 chararallB.Color collocation of the platethere are four kinds of color collocation for the Chinese vehicle license plate . these color collocations are shown in table ITABLE ICategory of license plateColor collocationSmall horse power plateblue background and white charactersMotor truck plateyellow background and black charactersmilitary vehicle and police wagon plateblack background and the white charactersEmbassy vehicle platewhite background and black charactersMoreover，military vehicle and police wagon plates contains a red character which belongs to a specific character set。this feature can be used to improve the recognition rate。C.Layout of the Chinese VLPSthe criterion of the vehicle license plate defines the characters layout of Chinese license plates . all standard license plates containing Chinesethe second one is a Letter ranging from a to z except the Letter I . the third and fourth ones are letters or numbers。the fifth To seventh ones are numbers ranging from 0 To 9 only。however the first or the seventh ones may be red characters in special plates(as shown in fig . 1)。after segmentation process the individual character is extracted。taking advantage of The layout and color collocation prior knowledge，The individual character will enter one of The classes : abbreations约巴BA9083中国CharacterCharacterLetter文字号码号码(a)Typical layout莉亚BB092警察中国CharacterCharacterLetter文字号码Special redCharacter(b) Special characterfig . 1 the layout of the Chinese license plate三.THE PROPOSED ALGORITHMthis algorithm conists of four modules : VLP location、character segmentation、Character class ification and Character recognitionthe main steps of the flow chart of lpr system are shown in fig . 2firstly the license plate is localted in an input image and characters are segmented . then every individual character image enters the classifier toImage acquisitionPlate位置characters segmentation segmentationClassifier中国CharacterLetter文字号码号码特殊字符Characters recognitionFig.2 The flowchart of LPR systemA.Pr