how can I convert many images from m x n x 3 to m x n by rgb2gray?

I want to convert 50 .jped images in a folder alltogether

[Geoff Hayes]

Bajdar - try https://www.mathworks.com/matlabcentral/answers/266978-how-to-convert-all-jpg-images-to-gray-and-then-save-them-in-different-file or another similar question and answer in this forum.

[Bajdar Nour]

Dear Geoff Hayes thank you very much, exucusme how Could I write them by imwrite in another folder?because the convertrd and orginal images mix in the same folder

[Geoff Hayes]

You would need to come up with a naming convention for the grayscale images and/or determine where these new files should be written to.

[Bajdar Nour]

thanks again

Answer 1

[KSSV]

img = dir('*.jpeg') ; 
N = length(img) ; 
for i = 1:N
    thisimg = img(i).name ; 
    I = imread(thisimg) ; 
    Ig = rgb2gray(I) ; 
    [dir,name,ext] = fileparts(thisimg) ; 
    filename = [name,'_gray','.jpeg'] ;
    imwrite(Ig,filename) ; 
end

Answer 2

[Image Analyst]

See the FAQ

https://matlab.fandom.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

In the loop, use sprintf() to build up your filename and use rgb2gray() if ndims() of the image is 3.