--- a
+++ b/functions/find_th_focus.m
@@ -0,0 +1,107 @@
+function thFocusFinal = find_th_focus(imagesCellTrain, TrnLabels, imageSize, dirUtilities, fidLogs)
+
+
+%read
+focusAll_Trn = -1 .* ones(numel(imagesCellTrain), 1);
+%loop read
+parfor f = 1 : numel(imagesCellTrain)
+% for f = 1 : numel(imagesCellTrain)
+    
+    %im
+    im = imagesCellTrain{f};
+    
+    %resize
+    im = imresize(im, imageSize);
+    
+    %focus
+    [scoreFocus] = assessFocusFQPath(im, [], dirUtilities, 0);
+    
+    %assign
+    focusAll_Trn(f) = scoreFocus;
+    
+end %for f
+
+
+%correlation initial
+correlationVanilla = computeCorrelation(focusAll_Trn', TrnLabels);
+%display
+%fprintf_pers(fidLogs, ['\tCorrelation initial: ' num2str(correlationVanilla) '\n']);
+
+
+%--------------------------------------
+%minimize correlation between focus and labels
+%display
+%fprintf_pers(fidLogs, '\tMinimize correlation\n');
+%init
+thFocus = 9;
+focusProc = -1 .* ones(numel(imagesCellTrain), 1);
+correlationProc = abs(correlationVanilla * 2);
+correlationProcPrev = correlationProc * 2;
+thFocusFinal = 1000;
+correlationProcMin = 1000;
+
+%loop on decreasing values of thFocus
+%while abs(correlationProc) < abs(correlationProcPrev)
+for ww = 1 : 30
+%%%%%%%%%%%%%%%%%
+% for ww = 1 : 5
+%%%%%%%%%%%%%%%%%
+    
+    %display
+    %fprintf_pers(fidLogs, ['\t\tthFocus: ' num2str(thFocus) '\n']);
+    
+    %loop
+    parfor f = 1 : numel(imagesCellTrain)
+        %for f = 1 : numel(imagesCellTrain)
+        
+        im = imagesCellTrain{f};
+        
+        %resize
+        im = imresize(im, imageSize);
+        
+        %display
+        %if mod(f, stepPrint) == 0
+        %fprintf_pers(fidLogs, ['\t\t\t' filenameTrn{f} '\n']);
+        %end %if mod
+        
+        %process
+        radius = 1;
+        iterF = 1;
+        im_temp = im;
+        [scoreFocus] = assessFocusFQPath(im, [], dirUtilities, 0);
+        while scoreFocus > thFocus && iterF < 10
+            im_temp = imsharpen(im, 'Radius', radius);
+            [scoreFocus] = assessFocusFQPath(im_temp, [], dirUtilities, 0);
+            radius = radius + 2;
+            iterF = iterF + 1;
+        end %for f
+        im = im_temp;
+        
+        focusProc(f) = scoreFocus;
+        
+    end %for g
+    
+    %update correlation values
+    correlationProcPrev = correlationProc;
+    correlationProc = computeCorrelation(focusProc', TrnLabels);
+    
+    %
+    if abs(correlationProc) < correlationProcMin
+        correlationProcMin = abs(correlationProc);
+        thFocusFinal = thFocus;
+    end %if correlation
+    
+    %display
+    %fprintf_pers(fidLogs, ['\t\t\tCorrelation: ' num2str(correlationProc) '\n']);
+    
+    %decrease thFocus
+    thFocus = thFocus - 0.1;
+    
+end %while correlationProc
+
+
+%display
+fprintf_pers(fidLogs, ['\t\tth_focus: ' num2str(thFocusFinal) '\n']);
+
+
+