Analog Protection System


Analog Protection System

The Analog Protection System (APS), also known as Copyguard, is a DVD copy prevention system originally developed by Macrovision. Video tapes copied from DVDs encoded with APS become garbled and unwatchable. The process works by adding pulses to analog video signals to negatively impact the AGC circuit of a recording device. In digital devices changes to the analog video signal are created by a chip that converts the digital video to analog within the device. In DVD players trigger bits are created during DVD authoring to inform the APS that it should be applied to DVD players analog outputs or analog video outputs on a PC while playing back a protected DVD-Video disc. In set top boxes trigger bits are incorporated into Conditional Access Entitlement Control Messages (ECM) in the stream delivered to the STB. In VHS alterations to the analog video signal are added in a Macrovision-provided “processor box” used by duplicators.

APS can be also signaled digitally, in the CGMS-A bit field sent in the vertical blanking interval.

Sources


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Analog hole — The analog hole is a fundamental and inevitable vulnerability in copy prevention schemes for noninteractive works in digital formats which can be exploited to duplicate copy protected works that are ultimately reproduced using analog means. Once… …   Wikipedia

  • Copy protection — Copy protection, also known as content protection, copy obstruction, copy prevention and copy restriction, refer to techniques used for preventing the reproduction of software, films, music, and other media, usually for copyright reasons.[1]… …   Wikipedia

  • High-bandwidth Digital Content Protection — (HDCP) is a form of digital copy protection developed by Intel Corporation to prevent copying of digital audio and video content as it travels across DisplayPort, Digital Visual Interface (DVI), High Definition Multimedia Interface (HDMI),… …   Wikipedia

  • DCS Copy Protection — Ltd is a UK company that licenses proprietary content protection technology. It is a direct competitor to Rovi (formerly Macrovision) in the field of analogue copy protection.[1] DCS Copy Protection Ltd is a wholly owned subsidiary of Echostar… …   Wikipedia

  • Engine indicating and crew alerting system — An example of information found on a EICAS Engine Indicating and Crew Alerting System (EICAS) is an integrated system used in modern aircraft to provide aircraft crew with aircraft engines and other systems instrumentation and crew annunciations …   Wikipedia

  • Cathodic protection rectifier — Cathodic protection rectifiers are AC powered electrical equipment that provide direct current for impressed current cathodic protection systems.Rectifier units are often custom manufactured and equipped with a variety of features, including oil… …   Wikipedia

  • Advanced Access Content System — AACS decryption process The Advanced Access Content System (AACS) is a standard for content distribution and digital rights management, intended to restrict access to and copying of the next generation of optical discs and DVDs. The specification …   Wikipedia

  • Broadcast Protection Discussion Group — The Broadcast Protection Discussion Group (BPDG) is a working group of content providers, television broadcasters, consumer electronics manufacturers, information technology companies, interested individuals and consumer activists. The group was… …   Wikipedia

  • Sound reinforcement system — A sound reinforcement system is an arrangement of microphones, electronic signal processors, amplifiers, and loudspeakers that makes live or pre recorded sounds usually music or speech louder, or that distributes the sound to a larger or more… …   Wikipedia

  • Fuzzy control system — Fuzzy control and Fuzzy Control redirect here. For the rock band, see Fuzzy Control (band). A fuzzy control system is a control system based on fuzzy logic a mathematical system that analyzes analog input values in terms of logical variables that …   Wikipedia