边缘

%显示原图
>> figure,imshow(lena);
>> title('Original image');
>> 
%高斯模糊图片
>> h=fspecial('gaussian',[11 11],4);
>> figure,surf(h);
>> lenasmooth=imfilter(lena,h);
>> figure,imshow(lenasmooth);
>> title('smoothed lena');
%左右移动图片，再相减
>> lenaL=lena;
>> lenaL=lenasmooth;
>> lenaL(:,[1:(end-1)])=lenaL(:,[2:end]);
>> lenaR=lenasmooth;
>> lenaR(:,[2:(end)])=lenaR(:,[1:(end-1)]);
>> lenaDiff=double(lenaR)-double(lenaL);
>> figure,imshow(lenaDiff,[]),title('Diff');
%canny与log边缘
>> cannyEdges=edge(lena,'canny');
>> figure,imshow(cannyEdges),title('canny');
>> logEdges=edge(lena,'log');
>> figure,imshow(logEdges),title('logEdges');