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']);