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ATSC Tuner
An ATSC (Advanced Television Systems Committee) tuner, often called an ATSC receiver or HDTV tuner, is a type of television tuner that allows reception of digital television (DTV) television channels that use ATSC standards, as transmitted by television stations in North America, parts of Central America, and South Korea. Such tuners are usually integrated into a television set, VCR, digital video recorder (DVR), or set-top box which provides audio/video output connectors of various types. Another type of television tuner is a digital television adapter (DTA) with an analog passthrough. Technical overview The terms "tuner" and "receiver" are used loosely, and it is perhaps more appropriately called an ATSC receiver, with the tuner being part of the receiver (see Metonymy). The receiver generates the audio and video (AV) signals needed for television, and performs the following tasks: demodulation; error correction; MPEG transport stream demultiplexing; decompression; AV synchro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPEG Transport Stream HL
The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by ISO and IEC that sets standards for media coding, including compression coding of audio, video, graphics, and genomic data; and transmission and file formats for various applications.John Watkinson, ''The MPEG Handbook'', p. 1 Together with JPEG, MPEG is organized under ISO/IEC JTC 1/SC 29 – ''Coding of audio, picture, multimedia and hypermedia information'' (ISO/IEC Joint Technical Committee 1, Subcommittee 29). MPEG formats are used in various multimedia systems. The most well known older MPEG media formats typically use MPEG-1, MPEG-2, and MPEG-4 AVC media coding and MPEG-2 systems transport streams and program streams. Newer systems typically use the MPEG base media file format and dynamic streaming (a.k.a. MPEG-DASH). History MPEG was established in 1988 by the initiative of Dr. Hiroshi Yasuda ( NTT) and Dr. Leonardo Chiariglione (CSELT). Chiariglione was the group's ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiplexing
In telecommunications and computer networking, multiplexing (sometimes contracted to muxing) is a method by which multiple analog or digital signals are combined into one signal over a shared medium. The aim is to share a scarce resource - a physical transmission medium. For example, in telecommunications, several telephone calls may be carried using one wire. Multiplexing originated in telegraphy in the 1870s, and is now widely applied in communications. In telephony, George Owen Squier is credited with the development of telephone carrier multiplexing in 1910. The multiplexed signal is transmitted over a communication channel such as a cable. The multiplexing divides the capacity of the communication channel into several logical channels, one for each message signal or data stream to be transferred. A reverse process, known as demultiplexing, extracts the original channels on the receiver end. A device that performs the multiplexing is called a multiplexer (MUX), and a dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcast Television
Broadcast television systems (or terrestrial television systems outside the US and Canada) are the encoding or formatting systems for the transmission and reception of terrestrial television signals. Analog television systems were standardized by the International Telecommunication Union in 1961, with each system designated by a letter ( A- N) in combination with the color standard used (NTSC, PAL or SECAM) - for example PAL-B, NTSC-M, etc.). These analog systems for TV broadcasting dominated until the 2010s. With the introduction of digital terrestrial television (DTT), they were replaced by four main systems in use around the world: ATSC, DVB, ISDB and DTMB. Analog television systems Every analog television system bar one began as a black-and-white system. Each country, faced with local political, technical, and economic issues, adopted a color television standard which was grafted onto an existing monochrome system such as CCIR System M, using gaps in the video spectrum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Format Descriptor
In television technology, Active Format Description (AFD) is a standard set of codes that can be sent in the MPEG video stream or in the baseband SDI video signal that carries information about their aspect ratio and other active picture characteristics. It has been used by television broadcasters to enable both 4:3 and 16:9 television sets to optimally present pictures transmitted in either format. It has also been used by broadcasters to dynamically control how down-conversion equipment formats widescreen 16:9 pictures for 4:3 displays. Standard AFD codes provide information to video devices about where in the coded picture the active video is and also the "protected area" which is the area that needs to be shown. Outside the protected area, edges at the sides or the top can be removed without the viewer missing anything significant. Video decoders and display devices can then use this information, together with knowledge of the display shape and user preferences, to choose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TV Set
A television set or television receiver, more commonly called the television, TV, TV set, telly, tele, or tube, is a device that combines a tuner, display, and loudspeakers, for the purpose of viewing and hearing television broadcasts, or using it as a computer monitor. Introduced in the late 1920s in mechanical form, television sets became a popular consumer product after World War II in electronic form, using cathode ray tube (CRT) technology. The addition of color to broadcast television after 1953 further increased the popularity of television sets in the 1960s, and an outdoor antenna became a common feature of suburban homes. The ubiquitous television set became the display device for the first recorded media in the 1970s, such as , VHS and later DVD. It has been used as a display device since the first generation of (e.g. Timex Sinclair 1000) and dedicated video game consoles (e.g. Atari) in the 1980s. By the early 2010s, flat-panel television incorporating liquid-cryst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HDTV
High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the generation following standard-definition television (SDTV), often abbreviated to HDTV or HD-TV. It is the current de facto standard video format used in most broadcasts: terrestrial broadcast television, cable television, satellite television and Blu-ray Discs. Formats HDTV may be transmitted in various formats: * 720p (1280 horizontal pixels × 720 lines): 921,600 pixels * 1080i (1920×1080) interlaced scan: 1,036,800 pixels (~1.04 MP). * 1080p (1920×1080) progressive scan: 2,073,600 pixels (~2.07 MP). ** Some countries also use a non-standard CEA resolution, such as 1440×1080i: 777,600 pixels (~0.78 MP) per field or 1,555,200 pixels (~1.56 MP) per frame When transmitted at two megapixels per frame, HDTV provides about five times a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pillarboxing
The pillarbox effect occurs in widescreen video displays when black bars (mattes or masking) are placed on the sides of the image. It becomes necessary when film or video that was not originally designed for widescreen is shown on a widescreen display, or a narrower widescreen image is displayed within a wider aspect ratio, such as a 16:9 image in a 2.39:1 frame (common in cinemas). The original material is shrunk and placed in the middle of the widescreen frame. Some older arcade games that had a tall vertical and short horizontal are displayed in pillarbox even on 4:3 televisions. Some early sound films made 1928–1931, such as '' Sunrise: A Song of Two Humans'', were released in even narrower formats such as 1.20:1 to make room for the sound-on-film track on then-standard film stock. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Letterboxing (filming)
Letterboxing is the practice of transferring film shot in a widescreen aspect ratio to standard-width video formats while preserving the film's original aspect ratio. The resulting videographic image has mattes (black bars) above and below it; these mattes are part of each frame of the video signal. LBX and LTBX are identifying abbreviations for films and images thus formatted. Etymology The term refers to the shape of a letter box, a slot in a wall or door through which mail is delivered, being rectangular and wider than it is high. Early home video use The first use of letterbox in consumer video appeared with the RCA Capacitance Electronic Disc (CED) videodisc format. Initially, letterboxing was limited to several key sequences of a film such as opening and closing credits, but was later used for entire films. The first fully letterboxed CED release was '' Amarcord'' in 1984, and several others followed including '' The Long Goodbye'', ''Monty Python and the Holy Grail' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image Scaling
In computer graphics and digital imaging, image scaling refers to the resizing of a digital image. In video technology, the magnification of digital material is known as upscaling or resolution enhancement. When scaling a vector graphic image, the graphic primitives that make up the image can be scaled using geometric transformations, with no loss of image quality. When scaling a raster graphics image, a new image with a higher or lower number of pixels must be generated. In the case of decreasing the pixel number (scaling down) this usually results in a visible quality loss. From the standpoint of digital signal processing, the scaling of raster graphics is a two-dimensional example of sample-rate conversion, the conversion of a discrete signal from a sampling rate (in this case the local sampling rate) to another. Mathematical Image scaling can be interpreted as a form of image resampling or image reconstruction from the view of the Nyquist sampling theorem. According to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame Rate
Frame rate (expressed in or FPS) is the frequency (rate) at which consecutive images (frames) are captured or displayed. The term applies equally to film and video cameras, computer graphics, and motion capture systems. Frame rate may also be called the , and be expressed in hertz. Frame rate in electronic camera specifications may refer to the maximal possible rate, where, in practice, other settings (such as exposure time) may reduce the frequency to a lower number. Human vision The temporal sensitivity and resolution of human vision varies depending on the type and characteristics of visual stimulus, and it differs between individuals. The human visual system can process 10 to 12 images per second and perceive them individually, while higher rates are perceived as motion. Modulated light (such as a computer display) is perceived as stable by the majority of participants in studies when the rate is higher than 50 Hz. This perception of modulated light as steady is known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspect Ratio (image)
The aspect ratio of an image is the ratio of its width to its height, and is expressed with two numbers separated by a colon, such as ''16:9'', sixteen-to-nine. For the ''x'':''y'' aspect ratio, the image is ''x'' units wide and ''y'' units high. Common aspect ratios are 1.85:1 and 2.39:1 in cinematography, 4:3 and 16:9 in television photography, and 3:2 in still photography. Some common examples The common film aspect ratios used in cinemas are 1.85:1 and 2.39:1.The 2.39:1 ratio is commonly labeled 2.40:1, e.g., in the American Society of Cinematographers' ''American Cinematographer Manual'' (Many widescreen films before the 1970 SMPTE revision used 2.35:1). Two common videographic aspect ratios are 4:3 (1.:1), the universal video format of the 20th century, and 16:9 (1.:1), universal for high-definition television and European digital television. Other cinema and video aspect ratios exist, but are used infrequently. In still camera photography, the most common aspect ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progressive Scan
Progressive scanning (alternatively referred to as noninterlaced scanning) is a format of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence. This is in contrast to interlaced video used in traditional analog television systems where only the odd lines, then the even lines of each frame (each image called a video field) are drawn alternately, so that only half the number of actual image frames are used to produce video. The system was originally known as "sequential scanning" when it was used in the Baird 240 line television transmissions from Alexandra Palace, United Kingdom in 1936. It was also used in Baird's experimental transmissions using 30 lines in the 1920s. Burns, R.W. ''John Logie Baird, Television Pioneer'', Herts: The Institution of Electrical Engineers, 2000. 316. Progressive scanning became universally used in computer screens beginning in the early 21st century. Interline twitter This rough animation c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
