get normal frames

+inputheader = '..\data\Normal_all\';
+outfolder = '..\data\Normal_frames\';
+
+files = dir(inputheader);
+id = {files.name};
+%  files + dir  file 
+flag = ~strcmp(id, '.') & ~strcmp(id, '..'); 
+files = files(flag);
+
+
+for i = 1 : length(files)
+
+    id = split(files(i).name, '.nii');
+    id = char(id(1));
+    fprintf('ID #%d = %s\n', i, id);
+    filename = id; % BraTS19_2013_2_1_seg_flair.nii
+    data_path = strcat(inputheader,'\', filename);
+    data = niftiread(data_path); %size 240x240x155 
+
+    [x,y,z] = size(data);
+
+    c = 0;
+
+    for k = 18:24
+        type = '.png';
+        filename = strcat(id, '_', int2str(c), type); % BraTS19_2013_2_1_seg_flair_c.png
+        outpath = strcat(outfolder, filename);
+        % typecase int16 to double, range[0, 1], rotate 90 and filp updown
+        % range [0, 1]
+        %cp_data = flipud(rot90(mat2gray(double(data(:,:,k)))));
+        cp_data = flipud(rot90(mat2gray(double(data(:,:,k)))));
+%         M = max(cp_data(:));
+%         disp(M);
+        imwrite(cp_data, outpath);
+        
+        c = c+ 1; 
+    end
+    
+end
+
+
+% p = 'st: %d\n';
+% fprintf(p, st);
+% p = 'en: %d\n';
+% fprintf(p, en);
+