How can I save images in a matrix?

Hello my friends . I get my images with this code, but what if I don't want to save all the images in the output? (last two lines)

That is, it should be stored in a matrix and finally saved in CSV or TXT format. In this way, I want any image that was needed to be displayed for me later.

clc
clear
close all
cd training_data_out\
folderInfo = dir('**/*.wav');
cd ..\
addpath training_data_out\
% working (current) folder
for i=1:length(folderInfo)
    filename = folderInfo(i).name
    [x,Fs] = audioread(filename);
    x=decimate(x,4);
      
        
    
%     % st transform
     [st_out,t,f]=st(x,25,350,1,1); 
     zz=abs(st_out);
     im = ind2rgb(im2uint8(rescale(zz)), colormap);
    
  
    filename_out = [filename(1:length(filename)-4) '.png']
    imwrite(imresize(im, [224 224]), filename_out);

Answer 1

[Walter Roberson]

Replace

 imwrite(imresize(im, [224 224]), filename_out);

with

 filenames{i} = filename_out;
 saved_im{i} = imresize(im, [224 224]);

Then later you can

 imshow(saved_im{i})

to view an image without having yet saved it to file.

When you finally decide to save it to csv of text file, you have a bit of a challenge. You used ind2rgb so we know that for sure the data for each file is RGB, which means it is stored as a 3D array. csv files are really only designed for 2D data, so it is not clear how you would like the 3D data stored in the csv file.

Answer 2

[Luca Ferro]

you can store them in a cell array by doing:

imgArray{1,1}=imread('whateverimage.png');
imgArray{1,2}=imread('whateverimage2.jpeg');
...
imgArray{1,n}=imread('whateverimageN.jpeg');

and so on. Obiously you can allocate them using the loop you already have.

Then to access them use curly brackets.

imgArray{1,1}