利用小波变换进行图像边缘提取，用matlab语言编写实现.zip

function edgedetect_basedonWavelet() %load woman; X=rgb2gray(imread('lena.jpg')); clear coef1; clear coef2; clear coef3; clear form; x=X; x=double(x);%200 line,300 column; line=250; column=250; J=6; Tu=7; smooth_area_num=20; edge_area_num=40; for i=1:line coef1(i,:)=cwt(x(i,:),1,'bior4.4'); coef2(i,:)=cwt(x(i,:),2,'bior4.4'); coef3(i,:)=cwt(x(i,:),J,'bior4.4'); end %正值1，负值0的矩阵temp表示(突变点左位置） max=0; max_loc=0; max_num=15; for i=1:line j=1; while j<column-1 if (coef3(i,j)>0 & coef3(i,j+1)<0) | (coef3(i,j)<0 & coef3(i,j+1)>0 )%找到左位置j for k=j+1:column-1 if coef3(i,k)*coef3(i,j)>=0%找到右位置k for m=j:k if abs(coef3(i,m))>max max=abs(coef3(i,m)); max_loc=m; end end if max>max_num form(i,max_loc)=1; end j=k; max=0; break; end end%for k if k==column-1 j=column-1; end else j=j+1; end%if end%while end %for i=1:line % for j=1:column % if abs(coef1(i,j))>=2*abs(coef2(i,j)) %是否加绝对值？!!!!!!!!!!!!!!!!!!!!!!!!!!! % form(i,j)=0;%第一种方法去噪声 % end % end %end %***************************************************** %对列作小波变换 x=x'; for i=1:line coef1(i,:)=cwt(x(i,:),1,'bior4.4'); coef2(i,:)=cwt(x(i,:),2,'bior4.4'); coef3(i,:)=cwt(x(i,:),J,'bior4.4'); end %正值1，负值0的矩阵temp表示(突变点左位置） max=0; max_loc=0; for i=1:line j=1; while j<column-1 if (coef3(i,j)>0 & coef3(i,j+1)<0) | (coef3(i,j)<0 & coef3(i,j+1)>0 )%找到左位置j for k=j+1:column-1 if coef3(i,k)*coef3(i,j)>=0%找到右位置k for m=j:k if abs(coef3(i,m))>max max=abs(coef3(i,m)); max_loc=m; end end if max>max_num form(max_loc,i)=1; end j=k; max=0; break; end end%for k if k==column-1 j=column-1; end else j=j+1; end%if end%while end %包括噪声在内的所有极值点① %for i=1:line % for j=1:column % if abs(coef1(i,j))>=2*abs(coef2(i,j)) %是否加绝对值？!!!!!!!!!!!!!!!!!!!!!!!!!!! % form(i,j)=0;%第一种方法去噪声 % end % end %end %此处添加用第二种方法去噪!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!② 结束 for i=2:line-2 for j=2:column-2 %链长为1 if form(i,j-1)==0 & form(i,j+1)==0 & form(i-1,j-1)==0 & form(i-1,j)==0 & form(i-1,j+1)==0 & form(i+1,j-1)==0 & form(i+1,j)==0 & form(i+1,j+1)==0 form(i,j)=0;% end %**************************************** %链长为2 %0000 %0110 %0000 if form(i,j)==1 & form(i,j+1)==1 & sum(sum(form(i-1:i+1,j-1:j+2)))==2 form(i,j)=0; form(i,j+1)=0; end %000 %010 %010 %000 if form(i,j)==1 & form(i+1,j)==1 & sum(sum(form(i-1:i+2,j-1:j+1)))==2 form(i,j)=0; form(i+1,j)=0; end %0000 %0100 %0010 %0000 if form(i,j)==1 & form(i+1,j+1)==1 & sum(sum(form(i:i+1,j:j+1)))==2 if sum(sum(form(i-1:i+2,j-1:j+2)))==3 & ( form(i-1,j+2)==1 | form(i+2,j-1)==1) form(i,j)=0; form(i+1,j+1)=0; end if sum(sum(form(i-1:i+2,j-1:j+2)))==4 & form(i-1,j+2)==1 & form(i+2,j-1)==1 form(i,j)=0; form(i+1,j+1)=0; end end %0000 %0010 %0100 %0000 if form(i,j+1)==1 & form(i+1,j)==1 & sum(sum(form(i:i+1,j:j+1)))==2 if sum(sum(form(i-1:i+2,j-1:j+2)))==3 & ( form(i-1,j-1)==1 | form(i+2,j+2)==1) form(i,j+1)=0; form(i+1,j)=0; end if sum(sum(form(i-1:i+2,j-1:j+2)))==4 & form(i-1,j-1)==1 & form(i+2,j+2)==1 form(i,j+1)=0; form(i+1,j)=0; end end end end %!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1!! max=0; for i=3:line-3 for j=3:column-3 s=sum(sum(form(i-2:i+2,j-2:j+2))); for m=i-2:i+2 for n=j-2:j+2 if s>=7 & abs(coef3(m,n))<=s*3 form(m,n)=0; end end end end end %显示form即为边缘检测图像 i=1; imshow(form,[]); end