Today almost all video and audio are produced and transported as compressed streams, often heavily so. We sweat bullets to create pristine digital-A/V signals that we squeeze down little pipes and dump into small bit buckets!

To maintain quality as compression standards change, everyone along the chain needs to constantly measure the performance of the compression engines on which day-to-day operations depend. "Digital compression" means having to make choices, including temporal resolution vs. noise, spatial resolution vs. image size, and luminance/color range vs. gamut.   More detail...