How do you calculate a PSNR for an image?

Peak Signal-to-Noise Ratio (PSNR) is calculated by first determining the Mean Squared Error (MSE) between the original and distorted images. MSE is computed by averaging the squared differences of pixel values. The PSNR is then calculated using the formula: ( PSNR = 10 \times \log_{10} \left(\frac{MAX^2}{MSE}\right) ), where ( MAX ) is the maximum possible pixel value (e.g., 255 for 8-bit images). Higher PSNR values indicate better image quality.