Rovi
![Macrovision pulses in an otherwise unused video line. Here they are large, forcing a VCR's auto contrast circuit to make the picture darker.](/Images/godic/202501/25/lossy-page1-200px-Macrovision_pulses_large.tif3919.jpg")
![A couple of seconds later, the pulses have reduced in amplitude, forcing a VCR's auto contrast circuit to make the picture lighter. A couple of seconds later still, the pulses return to their original amplitude, darkening the picture once more.](/Images/godic/202501/25/lossy-page1-200px-Macrovision_pulses_small.tif3919.jpg")
Rovi Corporation is a company based in the United States whose patents, products, and technologies include copy protection, software licensing and "search recommendation" on devices such as set-top boxes, digital video recorders, TVs, and mobile and tablet devices. Companies such as consumer electronics (CE) manufacturers, cable operators, websites, and social networks use Rovi’s entertainment metadata—a collection of in-depth information on movies, television shows, celebrities, music, games, and books—in their efforts to organize and enable the consumption of digital entertainment.