AnyDVD is a device driver for Microsoft Windows which allows decryption of DVDs on the fly, as well as targeted removal of copy preventions and user operation prohibitions (UOPs). With an upgrade, it will also do the same for HD DVD and Blu-ray Disc. The AnyDVD program runs in the background, making discs unrestricted and region-free. In addition to removing digital restrictions, AnyDVD will also defeat Macrovision analog copy prevention. Analog prevention distorts the video signal to prevent high quality copying from the output. AnyDVD is also able to remove copy-prevention from audio CDs.