Save each output in one file

Hi, anybody can help me from this code,

I want to save all peaksnr output into one .csv using writematrix, but this code only save one value into the .csv.

Is there any method i can use to make sure all the output save into one csv.

%% Here is my code

indir = uigerdir(cd, 'Select input folder');

directory = dir([indir, '\', '*.jpg']);

for i = 1 : length(directory)

filename = directory(i).name;

ref = imread([indir, '\', filename]);

A = imnoise(ref, 'salt & pepper', 0.02);

[peaksnr, snr] = psnr(A, ref);

fprintf('\n Peak-SNR Original : %0.4f',peaksnr);

fprintf('\n SNR Original : %0.4f \n',snr);

writematrix(peaksnr, sprintf('psnrO.csv',i+1))

end

Thank you for your help.

Answer 1

[Nur Farahin]

But, i've tried another solution an work for me as well.

indir = uigetdir(cd, 'Select input folder');

directory = dir([indir, '\', '*.jpg']);

for i = 1 : length(directory)

filename = directory(i).name;

ref = imread([indir, '\', filename]);

A = imnoise(ref, 'salt & pepper', 0.02);

[peaksnr, snr] = psnr(A, ref);

fprintf('\n Peak-SNR Original : %0.4f',peaksnr);

fprintf('\n SNR Original : %0.4f \n',snr);

writematrix(peaksnr,'psnrO.csv','WriteMode','append');

writematrix(snr,'snrO.csv','WriteMode','append');

end

just add the writemode and append argument, then the values will save all in one csv.

Answer 2

[VBBV]

writematrix(peaksnr, 'psnrO.xls','Sheet', i)

[VBBV]

Use the sheet argument in writematrix function. Writematrix function writes to appropriate file name specified as 2nd argument.sprintf is not necessary in this case.

[Nur Farahin]

If im not mistaken, the sheet argument is used with the .xcel method isnt. I already try put the sheet argument by have an error the sheet argument.

[Image Analyst]

CSV files are text files and do not have "sheets". I think @VBBV meant

writematrix(peaksnr, 'psnrO.xlsx','Sheet', i)

[VBBV]

Yes, sheet argument is used with *.xls files. Once saved into Excel file, you can convert it to CSV file using saveas option. Is there a constraint for you to write only to csv files ?, BTW you can use delimiter option in writematrix function too, if the data to be written has text

[Nur Farahin]

Thank you for the answer.

Answer 3

[Image Analyst]

Try (untested)

% Ask user for folder.
indir = uigetdir(cd, 'Select input folder');
directory = dir(fullfile(indir, *.jpg'));
% Preallocate array for results.
peaksnr = zeros(length(directory), 1);
% Loop over all files, adding noise and then computing Peak SNR and SNR
for k = 1 : length(directory)
    % Get this filename.
    filename = fullfile(indir, directory(k).name);
    % Read in image file from disk.
    originalImage = imread(filename); 
    % Add noise
    noisyImage = imnoise(originalImage, 'salt & pepper', 0.02);
    % Compute SNR
    [thisPSNR, thisSnr] = psnr(noisyImage, originalImage);
    % Update progress in command window.
    fprintf('\nPeak-SNR Original for "%s" (#%d of %d): %0.4f', ...
        directory(i).name, k, length(directory), thisPSNR);
    fprintf('\nSNR Original : %0.4f \n', thisSnr);
    % Save this value into the master array.
    peaksnr(k) = thisPSNR;
end
% Save all the values.
outputFileName = fullfile(indir, 'Peak SNR.xlsx');
writematrix(peaksnr, outputFileName);

[Nur Farahin]

Thank you for the asnwer. This work for me with a little adjustment on the code.

[Image Analyst]

Uh, you threw away all the corrections and improvements I made to your code, like

1. using fullfile(),
2. saving all the values to a single array so that you don't have to slow down your code by calling writematrix twice inside the loop,
3. better progress messages,
4. more descriptive variable names,
5. addition of lots of comments, etc.

OK, "not invented here" I guess.

[Nur Farahin]

I appreciated your improvement to my code, i am clearly understand very well. Thank you so much for helping me out. I am clearly understand very well and managed to run the code. Iam sorry if you feel your code is not invented. Hope you dont feel offended. Maybe someone else will need the code.