Peak Signal to Noise Ratio, commonly abbreviated as PSNR, refers to a mathematical formula that measures the quality of a digital signal. Synonyms for PSNR include Signal to Noise Ratio (SNR), Noise Figure (NF), Noise Floor, and Coefficient of Distortion (COD). These terms are used interchangeably in academic and industry research, and they all assess the noise level and distortion in a signal. PSNR and its synonyms are important measures in the digital communication industry, as they allow engineers to benchmark the performance of digital devices and transmission systems. By identifying improvements in PSNR, manufacturers can develop better audio and video codecs, modems, and wireless links that offer better sound and image quality.