Seam Carving代码

水平方向

function Emean=findEnergy(X)%求能量矩阵
[rows cols dim]=size(X);
Grd=[ 1  2  1;
      0  0  0;
     -1 -2 -1];
Emean=zeros(rows,cols);
for i=1:dim
    Eh(:,:,i)=conv2(X(:,:,i),Grd,'same');
    Ev(:,:,i)=conv2(X(:,:,i),Grd.','same');
    E(:,:,i)=abs(Eh(:,:,i))+abs(Ev(:,:,i));
end
Emean=1/dim*sum(E,3);  

function SeamVector=findSeam(X)%寻找seam向量
[rows cols]=size(X);
for j=cols:-1:1
    if j==cols
        [value, i]=min(X(:,cols));  %找最后一行的最小值，返回值的大小和所在列数
    else   
        if SeamVector(j+1)==1
            Vector=[Inf X(SeamVector(j+1),j) X(SeamVector(j+1)+1),j];
            elseif SeamVector(j+1)==rows
                 Vector=[X(SeamVector(j+1)-1,j) X(SeamVector(j+1),j) Inf];
            else
            Vector=[X(SeamVector(j+1)-1,j) X(SeamVector(j+1),j) X(SeamVector(j+1)+1,j)];
        end
        [Value Index]=min(Vector);
        IndexIncrement=Index-2;
        i=SeamVector(j+1)+IndexIncrement;
       end
    SeamVector(1,j)=i;
end

function SeamImg=findSeamImg(X)
[rows cols]=size(X);
SeamImg=zeros(rows,cols);
SeamImg(:,1)=X(:,1);

X=SeamPlot(X,SeamVector)
value=1.5*max(X(:));
[A,B]=size(SeamVector);
for j=1:B
    X(SeamVector(j),j)=value;
end

for j=2:cols 
    for i=1:rows 
        if i-1<1 SeamImg(i,j)= X(i,j)+min([SeamImg(i,j-1),SeamImg(i+1,j-1)]);    
        elseif i+1>rows SeamImg(i,j)= X(i,j)+min([SeamImg(i-1,j-1),SeamImg(i,j-1)]);  
        else SeamImg(i,j)= X(i,j)+min([SeamImg(i-1,j-1),SeamImg(i,j-1),SeamImg(i+1,j-1)]);  
        end 
    end
end

SeamVector=removalMap(X,lines); 
[rows cols dim]=size(X);
E=findEnergy(X);  
for j=1:min(lines,rows-1)
S=findSeamImg(E);
    SeamVector(j,:)=findSeam(S);
    X=SeamCut(X,SeamVector(j,:));
    E=SeamCut(E,SeamVector(j,:));
    [rows cols dim]=size(X);
end

X=SeamCut(X,SeamVector)
[rows cols dim]=size(X);
[SVrows SVcols SVdim]=size(SeamVector);
 
if cols~=SVcols
    error('SeamVector and image dimension mismatch');
end
 
for k=1:SVrows              
    for j=1:dim            
        for i=1:cols       
            if SeamVector(k,i)==1
                CutImg(:,i,j)=[X(2:rows,i,j)];
            elseif SeamVector(k,i)==rows
                CutImg(:,i,j)=[X(1:rows-1,i,j)];
            else
                CutImg(:,i,j)=[X(1:SeamVector(k,i)-1,i,j);X(SeamVector(k,i)+1:rows,i,j)];
            end
        end
    end
    X=CutImg;
    clear CutImg
    [rows cols dim]=size(X);
end

垂直方向

function SeamVector=findSeam(X) 
[rows cols]=size(X);
 for i=rows:-1:1
    if i==rows
        [value, j]=min(X(rows,:)); 
    else   
        if SeamVector(i+1)==1
            Vector=[Inf X(i,SeamVector(i+1)) X(i,SeamVector(i+1)+1)];
        elseif SeamVector(i+1)==cols
            Vector=[X(i,SeamVector(i+1)-1) X(i,SeamVector(i+1)) Inf];
        else
            Vector=[X(i,SeamVector(i+1)-1) X(i,SeamVector(i+1)) X(i,SeamVector(i+1)+1)];
        end
        [Value Index]=min(Vector);
        IndexIncrement=Index-2;
        j=SeamVector(i+1)+IndexIncrement;
    end
    SeamVector(i,1)=j;
end

SeamImg=findSeamImg(X)
[rows cols]=size(X);
SeamImg=zeros(rows,cols);
SeamImg(1,:)=X(1,:);  %X(1,：)表示矩阵的第一行
 for i=2:rows
    for j=1:cols
        if j-1<1
            SeamImg(i,j)= X(i,j)+min([SeamImg(i-1,j),SeamImg(i-1,j+1)]);
        elseif j+1>cols
            SeamImg(i,j)= X(i,j)+min([SeamImg(i-1,j-1),SeamImg(i-1,j)]);
        else
            SeamImg(i,j)= X(i,j)+min([SeamImg(i-1,j-1),SeamImg(i-1,j),SeamImg(i-1,j+1)]);
        end
    end
end

SeamVector=removalMap(X,lines); 
[rows cols dim]=size(X);
 E=findEnergy(X);   
 for i=1:min(lines,cols-1)
    S=findSeamImg(E);
    SeamVector(:,i)=findSeam(S);
    X=SeamCut(X,SeamVector(:,i));
    E=SeamCut(E,SeamVector(:,i));
    [rows cols dim]=size(X);
end

X=SeamCut(X,SeamVector)
[rows cols dim]=size(X);
[SVrows SVcols SVdim]=size(SeamVector);
 if rows~=SVrows
    error('SeamVector and image dimension mismatch');
end
 for k=1:SVcols             
    for i=1:dim             
        for j=1:rows       
            if SeamVector(j,k)==1
                CutImg(j,:,i)=[X(j,2:cols,i)];
            elseif SeamVector(j,k)==cols
                CutImg(j,:,i)=[X(j,1:cols-1,i)];
            else
                CutImg(j,:,i)=[X(j,1:SeamVector(j,k)-1,i) X(j,SeamVector(j,k)+1:cols,i)];
            end
        end
    end
    X=CutImg;
    clear CutImg
    [rows cols dim]=size(X);
end

X=SeamPlot(X,SeamVector)
value=1.5*max(X(:));
for i=1:size(SeamVector,1)
    X(i,SeamVector(i))=value;
end

总程序

X=imread('256V256.jpg');
X=double(X)/255;
[rows cols dim]=size(X);
Y=rgb2hsv(X);
    figure(1);  %原图
    imagesc(X)  
    axis equal  %坐标轴的长度单位设置成相等
% 获取灰度图像
E1=findEnergy(X);
    figure(2); 
    imshow(E1)
%寻找计算seam图像
S1=findSeamImg(E1);
     figure(3)
     imshow(S1,[min(S1(:)) max(S1(:))])
%寻seam    
SeamVector=findSeam(S1);
% 画出梯度图像的缝
SeamedImg=SeamPlot(X,SeamVector);
    figure(4);
    imshow(SeamedImg,[min(SeamedImg(:)) max(SeamedImg(:))])
%移除seam
SeamCutImg=SeamCut(X,SeamVector);
    figure(5);
    imshow(SeamCutImg)
%寻找并移除N个seams
M=removalMap(X,N);
MSeamedImg=SeamCut(X,M);
figure(6)
imshow(MSeamedImg)
imwrite(MSeamedImg,'N.jpg')