Multiple Image reconstruction with real and imaginary part in 2d array

I have two mat files one with real and another with imaginary part of 500 images. I am using the following line to reconstruct a single image :

" imshow(reshape(sqrt(a_imag(:,i).^2+a_real(:,i).^2),[128,128]) "

Each mat file is a 2D array (16384x500) with grayscale images of size 128x128. 'i' indiactes the image/column number.

I am trying to reconstruct all the 500 images and save each of them in .jpg format in the same order from 1-500. I tried this code and I am recieving an error.

a_real = load("img_real.mat");
a_imag = load("img_imag.mat");
for i = 1 : 500
    I(:,i) = reshape(sqrt(a_imag(:,i).^2+a_real(:,i).^2),[128,128]);
end
save('image', num2str(i),'.jpg');

Error:

Operator '.^' is not supported for operands of type 'struct'.

Error in image_recon (line 6)

I(:,i) = reshape(sqrt(a_imag(:,i).^2+a_real(:,i).^2),[128,128]);

Answer 1

[Matt J]

What is the name of the variable stored inside the .mat files? If I assume it is X, then,

a_real = load("img_real.mat").X;
a_imag = load("img_imag.mat").X;

[Shourya]

The variables are img_real and img_imag same as the file name.

[Matt J]

Then you should change .X to .img_real and .img_imag accordingly.

[Shourya]

@Matt J Thank you for your response. I replaced the X and I am recieving the following error.

Error:

Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.

I(:,i) = reshape(sqrt(a_imag(:,i).^2+a_real(:,i).^2),[128,128]);

[Walter Roberson]

You are reshaping to a 128 by 128 array, but expecting to be able to store the result in a vector I(I,i)

Consider

I(:,:,i) = reshape(sqrt(a_imag(:,i).^2+a_real(:,i).^2),[128,128]);

[Shourya]

@Walter Roberson Thank you for the solution. I made the changes tried the code and I am getting the following errors.

a_real = load("img_real.mat").img_real;
a_imag = load("img_imag.mat").img_imag;
for i = 1 : 500
    I(:,:,i) = reshape(sqrt(a_imag(:,i).^2+a_real(:,i).^2),[128,128]);
end
save('image', num2str(i),'.jpg');

Error:

Error using save

'500' is not a valid variable name.

Error in image_recon (line 11)

save('image', num2str(i),'.jpg');

I also tried for i = 1:size(a_real,2) and recieved the same error

[Matt J]

save('image','I');

[Shourya]

@Matt J Thank you. I made the changes and I was able to execute the code. But the images are'nt right I get error when I try to view the images.

a_real = load("img_real.mat").img_real;
a_imag = load("img_imag.mat").img_imag;
for i = 1 : 500
    I(:,:,i) = reshape(sqrt(a_imag(:,i).^2+a_real(:,i).^2),[128,128]);
    save(['image', num2str(i),'.jpg'], 'I');
end

Error reading the images:

a = imread('image99.jpg');

Error using imread>get_format_info (line 545)

Unable to determine the file format.

Error in imread (line 391)

fmt_s = get_format_info(fullname);

[Matt J]

a_real = load("img_real.mat").img_real;
a_imag = load("img_imag.mat").img_imag;

I = reshape(  sqrt(a_imag.^2+a_real.^2),  128,128,[]);

N=size(I,3);

filenames="image"+(1:N)+".jpg";

for i=1:N
    
    imwrite(I(:,:,i),filenames(i));
    
end

a = imread('image99.jpg');

[Shourya]

@Matt J Thank you this worked!