1、基于Harris的图像拼接技术MATLAB源代码基于Harris角点的图像拼接技术(MATLAB源代码)clcclear all% 读入图片pic1=imread(lena1.jpg);pic2=imread(lena2.jpg);% Harris角点检测points1=myHarris(pic1);points2=myHarris(pic2);% 画出Harris角点figure(1)drawHarrisCorner(pic1,points1,pic2,points2);% 角点特征描述des1=myHarrisCornerDescription(pic1,points1);des2=myH
2、arrisCornerDescription(pic2,points2);% 角点粗匹配matchs=myMatch(des1,des2);% 获取各自出匹配角点位置matchedPoints1=points1(matchs(:,1),:);matchedPoints2=points2(matchs(:,2),:);% 粗匹配角点连线figure(2)drawLinedCorner(pic1,matchedPoints1,pic2,matchedPoints2);% 角点精匹配newLoc1,newLoc2=pointsSelect(matchedPoints1,matchedPoints2)
3、;% 精匹配角点连线figure(3)drawLinedCorner(pic1,newLoc1,pic2,newLoc2);% 图像拼接im=picMatched(pic1,newLoc1,pic2,newLoc2);% 显示拼接图像figure(4)imshow(im);set(gcf,Color,w);function points=myHarris(pic)% 功能:寻找Harris角点% 输入:RGB图像或gray图像% 输出:角点所在的行、纵的N2矩阵if length(size(pic)=3 pic=rgb2gray(pic);endpic=double(pic);hx=-1 0
4、1;Ix=filter2(hx,pic);hy=-1;0;1;Iy=filter2(hy,pic);Ix2=Ix.*Ix;Iy2=Iy.*Iy;Ixy=Ix.*Iy;h=fspecial(gaussian,7 7,2);Ix2=filter2(h,Ix2);Iy2=filter2(h,Iy2);Ixy=filter2(h,Ixy);heigth,width=size(pic);alpha=0.06;R=zeros(heigth,width);for i=1:heigth for j=1:width M=Ix2(i,j) Ixy(i,j);Ixy(i,j) Iy2(i,j); R(i,j)=de
5、t(M)-alpha*(trace(M)2); endendRmax=max(max(R);pMap=zeros(heigth,width);for i=2:heigth-1 for j=2:width-1 if R(i,j)0.01*Rmax tm=R(i-1:i+1,j-1:j+1); tm(2,2)=0; if R(i,j)tm pMap(i,j)=1; end end endendrow,col=find(pMap=1);points=row,col;function drawHarrisCorner(pic1,points1,pic2,points2)% 功能:画出Harris角点的
6、连接% 输入:% pic1、pic2:待拼接的图像% points1、points2:Harris角点位置X1=points1(:,2);Y1=points1(:,1);X2=points2(:,2);Y2=points2(:,1);dif=size(pic1,2);imshowpair(pic1,pic2,montage);hold onplot(X1,Y1,b*);plot(X2+dif,Y2,b*);set(gcf,Color,w);function des=myHarrisCornerDescription(pic,points)% 功能:Harris角点特征描述% 输入:% pic:
7、原图像% points:角点位置% 输出:% des:8N的角点特征描述矩阵if length(size(pic)=3 pic=rgb2gray(pic);endlen=length(points);des=zeros(8,len);for k=1:len p=points(k,:); pc=pic(p(1),p(2); des(1,k)=pic(p(1)-1,p(2)-1)-pc; des(2,k)=pic(p(1),p(2)-1)-pc; des(3,k)=pic(p(1)+1,p(2)-1)-pc; des(4,k)=pic(p(1)+1,p(2)-pc; des(5,k)=pic(p(
8、1)+1,p(2)+1)-pc; des(6,k)=pic(p(1),p(2)+1)-pc; des(7,k)=pic(p(1)-1,p(2)+1)-pc; des(8,k)=pic(p(1)-1,p(2)-pc; des(:,k)=des(:,k)/sum(des(:,k);endfunction matchs=myMatch(des1,des2)% 功能:特征点双向匹配% 输入:% des1、des2:特征点描述信息构成的矩阵% 输出:% matchs:匹配的特征点对应关系len1=length(des1);len2=length(des2);match1=zeros(len1,2);co
9、r1=zeros(1,len2);for i=1:len1 d1=des1(:,i); for j=1:len2 d2=des2(:,j); cor1(j)=(d1*d2)/sqrt(d1*d1)*(d2*d2); end ,indx=max(cor1); match1(i,:)=i,indx;endmatch2=zeros(len2,2);cor2=zeros(1,len1);for i=1:len2 d2=des2(:,i); for j=1:len1 d1=des1(:,j); cor2(j)=(d1*d2)/sqrt(d1*d1)*(d2*d2); end ,indx=max(cor2
10、); match2(i,:)=indx,i;endmatchs=;for i=1:length(match1) for j=1:length(match2) if match1(i,:)=match2(j,:) matchs=matchs;match1(i,:); end endendfunction drawLinedCorner(pic1,loc1,pic2,loc2)% 功能:画出匹配角点的连接% 输入:% pic1、pic2:待拼接的图像% loc1、loc2:匹配角点位置X1=loc1(:,2);Y1=loc1(:,1);X2=loc2(:,2);Y2=loc2(:,1);dif=s
11、ize(pic1,2);imshowpair(pic1,pic2,montage);hold onfor k=1:length(X1) plot(X1(k),Y1(k),b*); plot(X2(k)+dif,Y2(k),b*); line(X1(k),X2(k)+dif,Y1(k),Y2(k),Color,r);endset(gcf,Color,w);function newLoc1,newLoc2=pointsSelect(loc1,loc2)% 功能:筛选匹配特征点对,获取高精度的控制点% 输入:% loc1、loc2:粗匹配特征点位置% 输出:% newLoc1、newLoc2:精匹配
12、控制点位置slope=(loc2(:,1)-loc1(:,1)./(loc2(:,2)-loc1(:,2);for k=1:3 slope=slope-mean(slope); len=length(slope); t=sort(abs(slope); thresh=t(round(0.5*len); ind=abs(slope)=1 & nx=1 & ny=SZ im(ny,nx,:)=pic2(i,j,:); end endendim=imresize(im,1,bicubic);tpic1=zeros(SZ,SZ,3);tpic1(1+cntrY:size(pic1,1)+cntrY,1
13、+cntrX:size(pic1,2)+cntrX,:)=pic1;re=rgb2gray(uint8(im)-rgb2gray(uint8(tpic1);for k=1:3 ta=im(:,:,k); tb=tpic1(:,:,k); ta(re=0)=tb(re=0); im(:,:,k)=ta;endclear ta tb re tpic1im=getPicture(im,SZ);im=uint8(im);if length(size(pic1)=2 im=rgb2gray(im);endfunction im=getPicture(pic,SZ)% 功能:获取图像有用区域% 输入:%
14、pic:拼接图像% SZ:预定图像尺寸% 输出:% im:有用区域图像if length(size(pic)=2 pic=cat(3,pic,pic,pic);endk=1;while k0 if any(any(pic(k,:,:) break end k=k-1;endbottom=k; %下边界k=1;while k0 if any(any(pic(:,k,:) break end k=k-1;endright=k; %右边界%获取图像im=pic(ceil:bottom,left:right,:);运行结果:A组实验图 拼接图像 A组检测出的Harris角点粗匹配的角点对连线去除无匹配之后的角点对连线拼接效果图B组实验图拼接图像 B组检测出的Harris角点粗匹配的角点对连线去除无匹配之后的角点对连线拼接效果图