Matlab实现将一副彩色扩展黑边

clear;
filenames = dir('E:\file');
N = length(filenames);
j=0;
for i=1:N
    [path,name,ext] = fileparts(filenames(i).name);
    if strcmp(ext,'.jpg') == 1
       
        imagedir = strcat('E:\王琳-04-25(new)\MindFind\MindFind\frame\',filenames(i).name);
        name = filenames(i).name;
        I = imread(imagedir);
        [m,n] = size(I);
       if m==256 && n== 384*3
           i
          I = imresize(I,[NaN 300]);
          R = I(:,:,1);
          G = I(:,:,2);
          B = I(:,:,3);
          [M,N] = size(R);
          K=double(R);
          for i=1:300
              for j=1:300
                  if (i>50)&&(i<=50+M)
                      C(i,j) = K(i-50,j);
                  else
                      C(i,j) = 0;
                  end
              end
          end
         C = uint8(C);
          
          L=double(G);
          for i=1:300
              for j=1:300
                  if (i>50)&&(i<=50+M)
                      D(i,j) = L(i-50,j);
                  else
                      D(i,j) = 0;
                  end
              end
          end
            D = uint8(D);
            
          T=double(B);
          for i=1:300
              for j=1:300
                  if (i>50)&&(i<=50+M)
                      E(i,j) = T(i-50,j);
                  else
                      E(i,j) = 0;
                  end
              end
          end
            E = uint8(E);
            
          Inew(:,:,1) = C;
          Inew(:,:,2) = D;
          Inew(:,:,3) = E;
          savename = strcat('E:\file',name);
          imwrite(Inew,savename);
          
      end
    end
    
end