Text output is printed multiple times

I am new to matlab. When i run my code, the output is printed multiple times with different values. What's wrong with this code?

InputImage=imread("img1.png");
ReconstructedImage=imread("img2.png");
n=size(InputImage);
M=n(1);
N=n(2);
MSE = sum(sum((InputImage-ReconstructedImage).^2))/(M*N);
PSNR = 10*log10(256*256/MSE);

fprintf('\nMSE: %7.2f ', MSE);
fprintf('\nPSNR: %9.7f dB', PSNR);

Output:

MSE:    0.70 
MSE:    0.61 
MSE:    0.99 
PSNR: 49.7147717 dB
PSNR: 50.3459133 dB
PSNR: 48.1905858 dB

Answer 1

[Star Strider]

The .png image is an (MxNx3) matrix, so the calculations occur for each ‘page’ in the third dimension.