help to assign correct image path to a variable

% dataset
  DB = 'MICC-F220';
  db_dir ='dataset';
  file_ground_truth = 'groundtruthDB_220.txt';
  % parameters
  metric = 'ward';
  th = 2.2;
  min_pts = 4;
  % load ground truth from a file
  [ImageName, GT] = textscan(fullfile(db_dir,DB,file_ground_truth), '%s %d');
  num_images = size(ImageName,1);
  fid_gt = fopen(fullfile(db_dir,DB,file_ground_truth));
  C = textscan(fid_gt, '%s %u');
  fclose(fid_gt);
  TP = 0;   % True Positive
  TN = 0;   % True Negative
  FP = 0;   % False Positive
  FN = 0;   % False Negative
  for i = 1:220
  %parfor i = 1:num_images   % use for parallel computation (needs matlabpool)
      loc_file = fullfile(db_dir,DB,cell2mat(ImageName{i}));
      name = cell2mat(ImageName{i}); 
      % process an image
      fprintf('Processing: %s (%d/%d)\n',loc_file,i,num_images);
      countTrasfGeom = process_image(loc_file, metric, th, min_pts, 0);         
      % tampering detection
      dim_v=size(C{1,1});
      for l=1:dim_v(1,1)
          if isequal(C{1,1}{l},ImageName{i})
              index=l;
          end
      end
      if countTrasfGeom>=1
          if C{1,2}(index)
              TP = TP+1;
          else
              FP = FP+1;
          end 
      else
          if C{1,2}(index)
              FN = FN+1;
          else
              TN = TN+1;
          end
      end
  end
  % compute performance             
  FPR  = FP/(FP+TN);
  TPR  = TP/(TP+FN);
  fprintf('\nCopy-Move Forgery Detection performance:\n');
  fprintf('\nTPR = %1.2f%%\nFPR = %1.2f%%\n', TPR*100, FPR*100);
  % compute computational time
  tproc = toc(tstart);
  tps = datestr(datenum(0,0,0,0,0,tproc),'HH:MM:SS');
  fprintf('\nComputational time: %s\n', tps);

Above is the script for processing a single image from a complete dataset of images. But on running the above code, following error is received:

Error using imread (line 350)
File "dataset\MICC-F220\dataset\MICC-F220\groundtruthDB_220.txt" does not exist.
Error in process_image (line 48)
image1 = imread(imagefile);
Error in run_F220_experiment (line 35)
     countTrasfGeom = process_image(loc_file, metric, th, min_pts, 0);

It clearly indicates that the variable named 'loc_file' in the above script has not been assigned a image correctly. It is also mentioned here that when we run the command given below in command window:

loc_file = fullfile(db_dir,DB,cell2mat(ImageName{i}));
the following result comes up:
loc_file =
  dataset\MICC-F220\dataset\MICC-F220\groundtruthDB_220.txt

Which clearly indicates, loc_file has not been assigned correct path of the image. Kindly suggest modifications..

[Image Analyst]

What is the value of "imagefile"? Is it a string with the name of a .txt file, or a valid image file?

[harpreet]

Sir, Although image file must be an image according to the syntax. But it depends upon the argument passed to the function- process-image, i.e. loc_file. Hence, loc_file must hold an image. But as the error shows, it is getting incorrect path means path is getting duplicated like: "dataset\MICC-F220\dataset\MICC-F220\groundtruthDB_220.txt"

P.s. the file groundtruth.txt contains names of all the images in the dataset on which experiment needs to be run.

Answer 1

[Sean de Wolski]

I think it needs to be '.\' at the beginning of the filename to specify relative path.

.\dataset\MICC-F220\dataset\MICC-F220\groundtruthDB_220.txt