matlab 读取子文件夹下的所有图片

filetrain = genpath('D:\CaffeInfo\B_DataCreate\cifar-10\train');

length_filetrain = size(filetrain,2);%字符串p的长度
path = {};%建立一个单元数组，数组的每个单元中包含一个目录
temp = [];
for i = 1:length_filetrain %寻找分割符';'，一旦找到，则将路径temp写入path数组中
if filetrain(i) ~= ';'
temp = [temp filetrain(i)];
else
temp = [temp '\']; %在路径的最后加入 '\'
path = [path ; temp];
temp = [];
end
end

for i = 2 : length(path)
sub_path = mat2str( cell2mat( path(i) ) );
sub_path = sub_path(2:end-1);
im_train = dir(sub_path);
for j = 3:length(im_train)
[i  j]
I = imread([sub_path, im_train(j).name]);
imwrite(I,['D:\CaffeInfo\B_DataCreate\train_image\', 'train', '_class-', num2str(i-2), '_num-', num2str(j-3), '.tif'])
end

end

%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
fileval = genpath('D:\CaffeInfo\B_DataCreate\cifar-10\val');

length_fileval = size(fileval,2);%字符串p的长度
path = {};%建立一个单元数组，数组的每个单元中包含一个目录
temp = [];
for i = 1:length_fileval %寻找分割符';'，一旦找到，则将路径temp写入path数组中
if fileval(i) ~= ';'
temp = [temp fileval(i)];
else
temp = [temp '\']; %在路径的最后加入 '\'
path = [path ; temp];
temp = [];
end
end

for i = 2 : length(path)
sub_path = mat2str( cell2mat( path(i) ) );
sub_path = sub_path(2:end-1);
im_val = dir(sub_path);
for j = 3:length(im_val)
[i  j]
I = imread([sub_path, im_val(j).name]);
imwrite(I,['D:\CaffeInfo\B_DataCreate\val_image\', 'val', '_class-', num2str(i-2), '_num-', num2str(j-3), '.tif'])
end

end