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Information about Ghost Canceling Reference

Ghost-canceling reference, or GCR, is a special sub-signal on a television channel that receivers can use to attenuate the ghosting effect of a television signal split into multiple paths between transmitter and receiver.

In the United States, the GCR signal is a chirp in frequency of the modulating signal from 0 Hz to 4.2 MHz, transmitted during the vertical blanking interval over one video line, shifted in phase by 180° once per frame. Television receivers generate their own local versions of this signal, and use the comparison between the local and remote signals to tune out any ghost images on the screen.

GCR was introduced after its recommendation in 1993 by the Advanced Television Systems Committee.[1]


[ edit ] Video formats
Analog broadcast
525 lines: NTSC | NTSC-J | PAL-M
625 lines: PAL | PAL-N | PALplus | SECAM
Defunct systems: Pre-1940 | 405 lines | 819 lines | Baird-Nipkow | MAC | MUSE
Multichannel audio: BTSC (MTS) | NICAM-728 | Zweiton (A2, IGR)
Hidden signals: Captioning | Teletext | CGMS-A | GCR | PDC | VBI | VEIL | VITC | WSS | XDS
Digital broadcast
Interlaced: SDTV (480i, 576i) | HDTV (1080i)
Progressive: LDTV (240p, 288p, 1seg) | EDTV (480p, 576p) | HDTV (720p, 1080p)
Digital TV standards: MPEG-2: ATSC, DVB, ISDB | MPEG-4: SBTVD
Multichannel audio: AAC (5.1) | Musicam | PCM | LPCM
Hidden signals: Captioning | Teletext | (CPCM/Broadcast flag) | AFD | EPG
Digital cinema: UHDV (2540p, 4320p) | DCI | 22.2 audio
Technical issues: | MPEG transport | Standards conversion | Video processing | VOD
Television (often abbreviated to TV, T.V., or more recently, tv; sometimes called telly, the tube, boob tube, or idiot box in British English) is a widely used telecommunication system for broadcasting and receiving moving pictures
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The term television channel generally refers to either a television station or its cable/satellite counterpart (both outlined below). Sometimes, it is confused with the term television network, which (when properly used) describes a group of geographically-distributed television
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Ghosting can have different meanings:
  • ghosting (television), a double image when receiving a distorted or multipath input signal in analog television broadcasting.

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multipath is the propagation phenomenon that results in radio signals' reaching the receiving antenna by two or more paths. Causes of multipath include atmospheric ducting, ionospheric reflection and refraction, and reflection from terrestrial objects, such as mountains and
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Motto
"In God We Trust"   (since 1956)
"E Pluribus Unum"   ("From Many, One"; Latin, traditional)
Anthem
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chirp is a signal in which the frequency increases ('up-chirp') or decreases ('down-chirp') with time. It is commonly used in sonar and radar, but has other applications, such as in spread spectrum communications.
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FreQuency is a music video game developed by Harmonix and published by SCEI. It was released in November 2001. A sequel, titled Amplitude was released in 2003.
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The vertical blanking interval (VBI), also known as the vertical interval or VBLANK, is the time interval between the end of the last line of one frame or field of a raster display, and the beginning of the next.
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A video format describes how one device sends video pictures to another device, such as the way that a DVD player sends pictures to a television, or a computer to a monitor.
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This article needs copy editing for grammar, style, cohesion, tone and/or spelling.
You can assist by [ editing it] now. A how-to guide is available, as is general .
This article has been tagged since October 2007.
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NTSC-J is an analog television system and video display standard for the region of Japan.

Technical definition

It is based on 'regular' NTSC, but is slightly different.
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PAL-M is the TV system used in Brazil since February 19, 1972. At that time, Brazil was the first country in South America with broadcasting in color. Rede Bandeirantes passed to PAL-M that year, while other television stations - like Rede Globo and Tupi - made a progressive and
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PAL, short for Phase Alternating Line, is a colour encoding system used in broadcast television systems in large parts of the world. Other common analogue television systems are SECAM and NTSC.
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PALplus is an extension of the PAL analogue broadcasting system for transmitting programs without sacrificing vertical resolution. A standard PAL receiver will display the image in letterbox format with 432 active lines, while a PALplus
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SECAM, also written SÉCAM (Séquentiel couleur à mémoire, French for "Sequential Color with Memory"), is an analog color television system first used in France.
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    ITU System Letter Designation.
  • The EMI system is officially known as System-A. As the EMI system predates PAL, there is no PAL designator in the ITU television system table.

USSR

  • USSR 1932 (mechanical): 30 lines, 12.

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The 405-line monochrome analogue television broadcasting system was the first electronic television system to be used in regular broadcasting. It was introduced with the BBC Television Service in 1936, suspended for the duration of World War II, and remained in operation in the UK
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Mechanical television was a television system that used mechanical or electromechanical devices to capture and display images. However, the images themselves were usually transmitted electronically and via radio waves.
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Multiplexed Analogue Components (MAC) was a satellite television transmission standard, originally proposed for use on a Europe-wide terrestrial HDTV system, although it was never used terrestrially.
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Analog broadcast
525 lines: NTSC | NTSC-J | PAL-M
625 lines: PAL | PAL-N | PALplus | SECAM
Defunct systems: Pre-1940 | 405 lines | 819 lines | Baird-Nipkow | MAC | MUSE
Multichannel audio: BTSC (MTS) | NICAM-728 | Zweiton (A2, IGR)
Hidden signals:
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Multichannel television sound, better known as MTS (often still as BTSC, for the Broadcast Television Systems Committee that created it), is the method of encoding three additional channels of audio into an NTSC-format audio carrier.
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NICAM stands for Near Instantaneous Companded Audio Multiplex. It is an early form of lossy compression for digital audio. It was originally developed in the early 1970s for point-to-point links within broadcasting networks.
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Zweikanalton ("two channel sound") is a television sound transmission system used in Germany and other countries. It relies on two separate FM carriers. This offers relatively high separation between the channels (compared to a subcarrier-based multiplex system) and can thus be
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The introduction to this article may be too long. Please help improve the introduction by moving some material from it into the body of the article according to the suggestions at Wikipedia's .
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Teletext (or "broadcast Teletext") is a television information retrieval service developed in the United Kingdom in the early 1970s. It offers a range of text-based information, typically including national, international and sporting news, weather and TV schedules.
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Copy Generation Management System - Analog (CGMS-A) is a copy protection mechanism for analog television signals. It is not related to the Broadcast flag, which is designed for use in digital television signals.
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For other meanings, see Startext (disambiguation).


Programme Delivery Control (PDC) is a standard (ETS 300 231) to control video recorders using hidden codes in the teletext service.
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Video Encoded Invisible Light (VEIL) is a technology for encoding low-bandwidth digital data bitstream in video signal, developed by VEIL Interactive Technologies. VEIL is compatible with multiple formats of video signals, including PAL, SECAM, and NTSC.
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Vertical Interval TimeCode (VITC, pronounced "vitsee" or sometimes "vits") is a form of SMPTE timecode embedded as a pair of black-and-white bars in a video signal. These lines are typically inserted into the vertical blanking interval of the video signal.
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In television technology, widescreen signaling (WSS) is a digital stream embedded in the TV signal describing qualities of the broadcast, in particular the intended aspect ratio of the image. This can be used by a widescreen TV to switch to the correct display mode.
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