VCR Plus+, G-Code, VideoPlus+ and ShowView are different names for the same scheduling system for programming VCRs and

digital video recorder A digital video recorder (DVR) is an electronic device that records video in a digital format to a disk drive, USB flash drive, SD memory card, SSD or other local or networked mass storage device. The term includes set-top boxes with direct to ...

s. These names are all registered trademarks of

Macrovision TiVo Corporation, formerly known as the Rovi Corporation and Macrovision Solutions Corporation, was an American technology company. Headquartered in San Jose, California, the company is primarily involved in licensing its intellectual property ...

, whose corporate predecessor, Gemstar, developed these algorithms for use in integrated

endec A codec is a device or computer program that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or ...

History

Before the advent of

on-screen display An on-screen display (OSD) is an image superimposed on a screen picture, commonly used by modern television sets, VCRs, and DVD players to display information such as volume, channel, and time. History In the past, most adjustments on TV sets ...

s, the only interface available for programming a home video recorder was a small VFD, LED or LCD panel and a small number of buttons. Correctly setting up a recording for a specific program was therefore a somewhat complex operation for many people. G-Code, VideoPlus+ and ShowView were introduced in the late 1980s to remove this difficulty.

Concept

The central concept of the system is a unique number, a PlusCode, assigned to each program, and published in television listings in newspapers and magazines (such as ''

TV Guide TV Guide is an American digital media company that provides television program listings information as well as entertainment and television-related news. The company sold its print magazine division, TV Guide Magazine LLC, in 2008. Corporat ...

''). To record a program, the code number is taken from the newspaper and input into the video recorder, which would then record on the correct channel at the correct time. The number is generated by an

algorithm In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing ...

from the date, time and channel of the program; as a result, it does not rely on an over-the-air channel to serve as a conduit to ensure the recording is properly timed. This means it will not compensate for a disrupted schedule due to live sporting events or bulletins for

breaking news Breaking news, interchangeably termed late-breaking news and also known as a special report or special coverage or news flash, is a current issue that broadcasters feel warrants the interruption of scheduled programming or current news in orde ...

events, however many video recorders with these systems also incorporate

Programme Delivery Control Programme delivery control (PDC) is specified by the standard ETS 300 231 (ETSI EN 300 231), published by the European Telecommunications Standards Institute (ETSI). This specifies the signals sent as hidden codes in the teletext service, indica ...

(PDC) and use that to alter times if possible.

Branding

The system has been licensed to television and VCR manufacturers in about 40 countries, but is branded under different names depending on the country. It is known as VCR Plus+, VCR Plus+ Silver and VCR Plus+ Gold in the United States and Canada; G-Code in Japan, China, New Zealand and Australia; VideoPlus+ in Ireland, the United Kingdom, and Japan; and ShowView in the rest of Europe as well as in

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring coun ...

. The system is branded as VideoPlus+/ShowView in Europe due to an existing trademark registration for "VCR" by

Philips Koninklijke Philips N.V. (), commonly shortened to Philips, is a Dutch multinational conglomerate corporation that was founded in Eindhoven in 1891. Since 1997, it has been mostly headquartered in Amsterdam, though the Benelux headquarters is ...

in that continent, and as G-Code (the "G" standing for the system's developer Gemstar) in Japan because VCR is not a common abbreviation there ("VTR," for videotape recorder, is used instead). Japan initially used the name Video Plus+ and later changed to G-Code, an example of this is the Victor (JVC) HR-880. Because television programming schedules are different, the coding has to be adjusted in each of the regions and recording equipment is not interchangeable.

Algorithms

The actual algorithms used to encode and decode the television guide values from and to their time representations were published in 1992, but only for six-digit codes or less. Source code for seven and eight digit codes was written in C and

Perl Perl is a family of two high-level, general-purpose, interpreted, dynamic programming languages. "Perl" refers to Perl 5, but from 2000 to 2019 it also referred to its redesigned "sister language", Perl 6, before the latter's name was offic ...

and posted anonymously in 2003.

References

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External links