實(shí)驗(yàn)七：基于神經(jīng)網(wǎng)絡(luò)的模式識(shí)別實(shí)驗(yàn)

1、實(shí)驗(yàn)七：基于神經(jīng)網(wǎng)絡(luò)的模式識(shí)別實(shí)驗(yàn)一、 實(shí)驗(yàn)?zāi)康睦斫釨P神經(jīng)網(wǎng)絡(luò)和離散Hopfield神經(jīng)網(wǎng)絡(luò)的結(jié)構(gòu)和原理，掌握反向傳播學(xué)習(xí)算法對(duì)神經(jīng)元的訓(xùn)練過(guò)程，了解反向傳播公式。通過(guò)構(gòu)建BP網(wǎng)絡(luò)和離散Hopfield網(wǎng)絡(luò)模式識(shí)別實(shí)例，熟悉前饋網(wǎng)絡(luò)和反饋網(wǎng)絡(luò)的原理及結(jié)構(gòu)。綜合掌握模式識(shí)別的原理，了解識(shí)別過(guò)程的程序設(shè)計(jì)方法。二、 實(shí)驗(yàn)內(nèi)容熟悉模式識(shí)別的理論方法，用選擇一種合適的識(shí)別方法，對(duì)圖像中的字符（英文字母）進(jìn)行識(shí)別，能夠區(qū)分出不同的形態(tài)的26個(gè)字母。在Matlab中，采用BP神經(jīng)網(wǎng)絡(luò)，對(duì)讀取的數(shù)據(jù)進(jìn)行訓(xùn)練，進(jìn)而識(shí)別。1. 程序設(shè)計(jì)(1)程序各流程圖實(shí)驗(yàn)中主程序流程圖如圖4-1所示：圖4-1 主程序流程圖

2、其中圖像預(yù)處理的流程如圖4-2 所示：圖像輸入灰度轉(zhuǎn)化圖像二值化圖像分割歸一化調(diào)整調(diào)整比例顯示預(yù)處理結(jié)果圖4-2 圖像預(yù)處理的流程神經(jīng)網(wǎng)絡(luò)訓(xùn)練的具體流程如圖4-3 所示：獲取圖像數(shù)據(jù)創(chuàng)建神經(jīng)網(wǎng)絡(luò)訓(xùn)練存儲(chǔ)訓(xùn)練好的神經(jīng)網(wǎng)絡(luò)圖4-3 神經(jīng)網(wǎng)絡(luò)訓(xùn)練流程(2)程序清單%形成用戶界面clear all;%添加圖形窗口H=figure('Color',0.85 0.85 0.85,. 'position',400 300 500 400,. 'Name','基于BP神經(jīng)網(wǎng)絡(luò)的英文字母識(shí)別',. 'NumberTitle',

3、9;off',. 'MenuBar','none');%畫(huà)坐標(biāo)軸對(duì)象，顯示原始圖像h0=axes('position',0.1 0.6 0.3 0.3);%添加圖像打開(kāi)按鈕h1=uicontrol(H,'Style','push',. 'Position',40 100 80 60,. 'String','選擇圖片',. 'FontSize',10,. 'Call','op');%畫(huà)坐標(biāo)軸對(duì)象，顯示經(jīng)過(guò)預(yù)處理之后

4、的圖像h2=axes('position',0.5 0.6 0.3 0.3);%添加預(yù)處理按鈕h3=uicontrol(H,'Style','push',. 'Position',140 100 80 60,. 'String','二值化',. 'FontSize',10,. 'Call','preprocess');%添加識(shí)別按鈕h4=uicontrol(H,'Style','push',. 'Position

5、',240 100 80 60,. 'String','字母識(shí)別',. 'FontSize',10,. 'Call','recognize');%添加顯示識(shí)別結(jié)果的文本框%添加訓(xùn)練神經(jīng)網(wǎng)絡(luò)按鈕h6=uicontrol(H,'Style','push',. 'Position',340 100 80 60,. 'String','網(wǎng)絡(luò)訓(xùn)練',. 'FontSize',10,.'Call','

6、Example1Tr');%預(yù)處理%preprocessp1=ones(16,16);bw=im2bw(X,0.5);%轉(zhuǎn)換成二值圖像%用矩形框截取圖像i,j=find(bw=0);imin=min(i);imax=max(i);jmin=min(j);jmax=max(j);bw1=bw(imin:imax,jmin:jmax);%調(diào)整比例，變換成16*16圖像rate=16/max(size(bw1);bw1=imresize(bw1,rate);i,j=size(bw1);i1=round(16-i)/2);j1=round(16-j)/2);p1(i1+1:i1+i,j1+1:

7、j1+j)=bw1;p1=-1.*p1+ones(16,16);%顯示預(yù)處理的結(jié)果axes(h2);imshow(p1);%Example1Tr，訓(xùn)練網(wǎng)絡(luò)M=1;%人數(shù)N=26*M;%樣本數(shù)%獲取26個(gè)大寫(xiě)字母圖像的數(shù)據(jù)for kk=0:N-1 p1=ones(16,16);%初始化16*16的二值圖像（全白） m=strcat(int2str(kk),'.bmp');%形成文件名 x=imread(m,'bmp');%讀取圖像 bw=im2bw(x,0.5);%轉(zhuǎn)換成二值圖像數(shù)據(jù) %用矩形框截取 i,j=find(bw=0);%查找像素為黑的坐標(biāo) %取邊界坐標(biāo)

8、 imin=min(i); imax=max(i); jmin=min(j); jmax=max(j); bw1=bw(imin:imax,jmin:jmax);%截取 %調(diào)整比例，縮放成16*16的圖像 rate=16/max(size(bw1); bw1=imresize(bw1,rate);%會(huì)存在轉(zhuǎn)換誤差 %將bw1轉(zhuǎn)換成標(biāo)準(zhǔn)的16*16圖像p1 i,j=size(bw1); i1=round(16-i)/2); j1=round(16-j)/2); p1(i1+1:i1+i,j1+1:j1+j)=bw1; p1=-1.*p1+ones(16,16); %將p1轉(zhuǎn)換成輸入向量 for

9、m=0:15 p(m*16+1:(m+1)*16,kk+1)=p1(1:16,m+1); endend%形成目標(biāo)向量for kk=0:M-1 for ii=0:25 t(kk+ii+1)=ii; endend%設(shè)置輸入向量范圍pr(1:256,1)=0;pr(1:256,2)=1;%創(chuàng)建兩層BP神經(jīng)網(wǎng)絡(luò)，隱層有25個(gè)節(jié)點(diǎn)net=newff(pr,25 1,'logsig' 'purelin','traingdx','learngdm');net.trainParam.epochs=2500;net.trainParam.goal=

10、0.001;net.trainParam.show=10;net.trainParam.lr=0.05;%訓(xùn)練神經(jīng)網(wǎng)絡(luò)net=train(net,p,t);%存儲(chǔ)訓(xùn)練好的神經(jīng)網(wǎng)絡(luò)%recognize，字符識(shí)別%生成向量形式M=figure('Color',0.75 0.75 0.75,. 'position',200 200 400 200,. 'Name','基于BP神經(jīng)網(wǎng)絡(luò)的英文字母識(shí)別結(jié)果',. 'NumberTitle','off',. 'MenuBar','none

11、');M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','請(qǐng)先訓(xùn)練網(wǎng)絡(luò)',. 'FontSize',12,. 'call','delete(M(1) ' ); for m=0:15 q(m*16+1:(m+1)*16,1)=p1(1:16,m+1);end%識(shí)別a,Pf,Af=sim(net,q);a=round(a);switch a case 0,M0=uicontrol

12、(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是A',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 1,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是B',. &#

13、39;FontSize',12,. 'call',. 'delete(M(1)'); case 2,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是C',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 3,M0=uicontrol(M,'Style','pus

14、h',. 'Position',150 80 130 40,. 'String','這個(gè)字母是D',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 4,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是E',. 'FontSize',12,. '

15、call',. 'delete(M(1)'); case 5,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是F',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 6,M0=uicontrol(M,'Style','push',. 'Position'

16、,150 80 130 40,. 'String','這個(gè)字母是G',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 7,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是H',. 'FontSize',12,. 'call',. 'delete(M(1

17、)'); case 8,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是I',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 9,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'Strin

18、g','這個(gè)字母是J',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 10,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是K',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 11,M0=uicont

19、rol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是L',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 12,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是M',

20、. 'FontSize',12,. 'call',. 'delete(M(1)'); case 13,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是N',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 14,M0=uicontrol(M,'Style',&#

21、39;push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是O',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 15,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是P',. 'FontSize',12,

22、. 'call',. 'delete(M(1)'); case 16,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是Q',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 17,M0=uicontrol(M,'Style','push',. 'Posi

23、tion',150 80 130 40,. 'String','這個(gè)字母是R',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 18,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是S',. 'FontSize',12,. 'call',. '

24、delete(M(1)'); case 19,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是T',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 20,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,

25、. 'String','這個(gè)字母是U',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 21,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是V',. 'FontSize',12,. 'call',. 'delete(M(1)'); case

26、22,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是W',. 'FontSize',12,. 'call',. 'delete(M(1)'); case 23,M0=uicontrol(M,'Style','push',. 'Position',150 80 130 40,. 'String','這個(gè)字母是X',. 'FontSize',12,. 'call',. 'de