How to read multiple jpg images in a loop?

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hello, i am a novice user in matlab my question is: i have stored some 100s of images in some folder and i want to read it one-by-one.how can i do this?
  17 Comments
Anil Varma
Anil Varma on 13 Dec 2019
showing error
Error using randi
First input must be a positive scalar integer value IMAX, or two integer values [IMIN IMAX] with IMIN
less than or equal to IMAX.
Error in test (line 9)
idx=randi(n);
shweta banait
shweta banait on 3 Dec 2020
Moved: DGM on 20 Dec 2022
how to display five images in matlab

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Accepted Answer

Dishant Arora
Dishant Arora on 4 Mar 2014
  6 Comments
archana
archana on 6 Mar 2014
Edited: archana on 6 Mar 2014
sir,actually i want to obtain the covarience matrix of all these read images...for same i wrote a code but there i worked on each image seperatly (i.e. reading convrting to gray and the resized it) because of which code became verry bulky ,now with your guidlines i modified sem for loop reading. now what i supposed to do is 1st i should convert it to gray and then resize all..but fact is yet i didnot reached to covarience matrix stage...:( apologize me for mistake if any
Dishant Arora
Dishant Arora on 6 Mar 2014
Use the builtin cov to get the covariance matrix.

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More Answers (5)

Karthik Karri
Karthik Karri on 6 Mar 2014
You can rename all images like..im1,im2,im3.....im100. To read 100 images one by one, run a loop 100 times with i as variable from 1 to 100 and in imread, m=imread(['folder_path\im' num2str(i) '.jpg']). I hope I answered your question.

chaitra naveen
chaitra naveen on 20 Mar 2017
can you please help me out to read 100's of images from folder to matlab and resize them to 100x100.

Muhammad Sohail
Muhammad Sohail on 27 Nov 2017
filelist = dir('Training data');
for i=1 : length(filelist)
for i=1 : length(filelist)
filename = filelist(i);
if ~strcmp(filename.name , '.') && ~strcmp(filename.name , '..')
filename.name
end
end

Haseeb Hassan
Haseeb Hassan on 30 Jun 2019
for i=1:16; % we have 16 images we have in or folder
clc;clear;
images ='C:\Users\Haseeb\Desktop\input\for_loop_input';
jpgfiles=dir(fullfile(images,'\*.jpg*'));
n=numel(jpgfiles(i));
im=jpgfiles(i).name
im1=imread(fullfile(images,im));
imshow(im1);
end
Here is the simple and short code, which will acces your images from your folder in a sequence.
  1 Comment
shital shinde
shital shinde on 21 Feb 2020
Actually it gives error as
Array indices must be positive integers or logical values.
n=numel(jpgfiles(i)); // for this line.
will you tell me why ?

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Xylo
Xylo on 6 Mar 2014
You can do this easily..... before doing this program, you have to keep all of your image in a folder and rename them by any common char+number concatenation form (like a1.jpg, a2.jpg,a3.jpg....). after that you just use strcat() function for reading the path name, and then read the images.
for i=1:10 %suppose there are 10 image
file_name=dir(strcat('J:\multimedia\photo\')); % the path tht u hv imges
im=imread(strcat('J:\multimedia\photo\',file_name(i).name));
imtool(im);
end
  8 Comments
Walter Roberson
Walter Roberson on 29 Nov 2016
Isha Pandya, please show your current code and describe what difficulty you are observing.
Zahoor abbas
Zahoor abbas on 9 Jul 2018
How I can access the images from two folders by using one for loop

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