How to read and pre-process the multiple images and write in specific location?

function preprocessing_multiple

srcFiles = dir('C:\Users\LENOVO\Desktop\Genuine\1\*.png');  % the folder in which ur images exists
for i = 1 : length(srcFiles)
    filename = strcat('C:\Users\LENOVO\Desktop\Genuine\1\',srcFiles(i).name);
    I = rgb2gray(imread(filename));
    imshow(I)
    I2=medfilt2(I);
    figure,imshow(I2)

imwrite(I2,fullfile('C:\Users\LENOVO\Desktop\','*.png'));
end

I got error in above code:

Error using imwrite (line 454)

Unable to open file "C:\Users\LENOVO\Desktop\*.png" for writing. You may not

have write permission.

Error in preprocessing_multiple (line 11)

imwrite(I2,fullfile('C:\Users\LENOVO\Desktop\','*.png'));

[Walter Roberson]

Every iteration you are trying to write to the same file whose name is literally *.png

Answer 1

[Geoff Hayes]

Regina - in your line of code

imwrite(I2,fullfile('C:\Users\LENOVO\Desktop\','*.png'));

which file are you trying to write to? You are not specifying a file name and are instead using the wildcard character. Try changing the above line of code so that you explicitly set the filename to which you want to write the I2 data to.

[Regina N]

Actually i want to save all the preprocessed images in one line code...So, plz u tell me the exact correction in this LOC.

[Geoff Hayes]

Regina - look closely at your code

for i = 1 : length(srcFiles)
    filename = strcat('C:\Users\LENOVO\Desktop\Genuine\1\',srcFiles(i).name);
    I = rgb2gray(imread(filename));
    imshow(I)
    I2=medfilt2(I);
    figure,imshow(I2)
    imwrite(I2,fullfile('C:\Users\LENOVO\Desktop\','*.png'));
end

The code is looping over all of the files that you have found, reading the file, doing some processing, and then (trying) to write to an incorrectly named file. So you won't be able to save all the preprocessed images in one line code. Instead, you can save each preprocessed file one at a time by replacing

imwrite(I2,fullfile('C:\Users\LENOVO\Desktop\','*.png'));

with

imwrite(I2,fullfile('C:\Users\LENOVO\Desktop\', srcFiles(i).name));

The above assumes that you want to write to a file with the same name as the original file (just in a different folder).

[Regina N]

Actually i am new to matlab....so....bt thank you so much for helping me..it works..thanx again