Mode 7 is a graphics mode on the Super NES video game console that allows a background layer to be rotated and scaled on a scanline-by-scanline basis to create many different effects. The most famous of these effects is the application of a perspective effect on a background layer by scaling and rotating the background layer in this manner; this transforms the background layer into a two-dimensional horizontal texture-mapped plane that trades height for depth. Thus, an impression of three-dimensional graphics is achieved. Mode 7 was one of Nintendo's prominent selling points for the Super NES platform in publications such as Nintendo Power and Super NES Player's Guide. Similar faux 3D techniques have been presented on a few 2D systems other than the Super NES, in select peripherals and games. Mode 7 games include the titles F-Zero, Pilotwings, Yoshi's Safari, Teenage Mutant Ninja Turtles IV: Turtles in Time, Super Castlevania IV, Secret of Mana, Secret of Evermore, Final Fantasy IV, Final Fantasy V, Final Fantasy VI, Super Mario RPG: Legend of the Seven Stars, DinoCity, HyperZone, Super Mario Kart, Super Mario World, Super Metroid, the Super Robot Wars series, Super Star Wars, Chrono Trigger, ActRaiser, Exhaust Heat, Skyblazer, 7th Saga, Mega Man 7, Kirby Super Star, Axelay, SOS, NCAA Basketball, NHL Stanley Cup, Al Unser Jr.'s Road to the Top, Rendering Ranger: R2, The Legend of Zelda: A Link to the Past, Zoku: The Legend of Bishin.
The visual effects were reimplemented by other means in the Game Boy Advance incarnations of many of these games. The Super NES console has eight graphics modes, numbered from 0 to 7, for displaying background layers; the last one rotated. This graphical method is suited to racing games, is used extensively for the overworld sections of role-playing games such as Square's popular 1994 game Final Fantasy VI; the effect enables developers to create the impression of sprawling worlds that continue toward the horizon. A particular utilization technique with Mode 7 allows pixels of the background layer to be in front of sprites. Examples include the second and fifth stage of Contra III: The Alien Wars, the second and fifth stage of Jim Power: The Lost Dimension in 3-D, the introduction screen of Tiny Toon Adventures: Buster Busts Loose, when a player falls off the stage in Super Mario Kart, some cinematics in Super Metroid, in some boss battles in Super Mario World; the Game Boy Advance can make the same effect by using mode 2 which provides two layers, by putting the sprites between the layers.
Mode 7 graphics are generated for each pixel by mapping screen coordinate r to background coordinate r ′ using an affine transformation and sampling the corresponding background color. The 2D affine transformation is specified for each scanline by 6 parameters. Screen coordinate r is translated to the origin coordinate system, the matrix is applied, the result is translated back to the original coordinate system to obtain r ′. In 2D matrix notation, this is written as r ′ = M + r 0 = +. All arithmetic is carried out on 16-bit signed fixed point numbers, while all offsets are limited to 13 bits; the radix point is between bits 7 and 8. Two-dimensional affine transformations can produce any combination of translation, reflection and shearing—and nothing else. However, many games create additional effects by setting a different transformation matrix for each scanline. In this way, pseudo-perspective, curved surface, distortion effects can be achieved. Mode 7 can only work on backgrounds, not sprites.
The game developer must create a sprite with the same appearance as that object. For instance, in Super Castlevania IV, battles in which a large boss such as Koranot rotates, have the mobile boss implemented as the background, while
Chrominance is the signal used in video systems to convey the color information of the picture, separately from the accompanying luma signal. Chrominance is represented as two color-difference components: U = B′ − Y′ and V = R′ − Y′; each of these difference components may have scale factors and offsets applied to it, as specified by the applicable video standard. In composite video signals, the U and V signals modulate a color subcarrier signal, the result is referred to as the chrominance signal. In digital-video and still-image color spaces such as Y′CbCr, the luma and chrominance components are digital sample values. Separating RGB color signals into luma and chrominance allows the bandwidth of each to be determined separately; the chrominance bandwidth is reduced in analog composite video by reducing the bandwidth of a modulated color subcarrier, in digital systems by chroma subsampling. The idea of transmitting a color television signal with distinct luma and chrominance components originated with Georges Valensi, who patented the idea in 1938.
Valensi's patent application described: The use of two channels, one transmitting the predominating color, the other the mean brilliance output from a single television transmitter to be received not only by color television receivers provided with the necessary more expensive equipment, but by the ordinary type of television receiver, more numerous and less expensive and which reproduces the pictures in black and white only. Previous schemes for color television systems, which were incompatible with existing monochrome receivers, transmitted RGB signals in various ways. In analog television, chrominance is encoded into a video signal using a subcarrier frequency. Depending on the video standard, the chrominance subcarrier may be either quadrature-amplitude-modulated or frequency-modulated. In the PAL system, the color subcarrier is 4.43 MHz above the video carrier, while in the NTSC system it is 3.58 MHz above the video carrier. The NTSC and PAL standards are the most used, although there are other video standards that employ different subcarrier frequencies.
For example, PAL-M uses a 3.58 MHz subcarrier, SECAM uses two different frequencies, 4.250 MHz and 4.40625 MHz above the video carrier. The presence of chrominance in a video signal is indicated by a color burst signal transmitted on the back porch, just after horizontal synchronization and before each line of video starts. If the color burst signal were visible on a television screen, it would appear as a vertical strip of a dark olive color. In NTSC and PAL, hue is represented by a phase shift of the chrominance signal relative to the color burst, while saturation is determined by the amplitude of the subcarrier. In SECAM and signals are transmitted alternately and phase does not matter. Chrominance is represented by the U-V color plane in PAL and SECAM video signals, by the I-Q color plane in NTSC. Digital video and digital still photography systems sometimes use a luma/chroma decomposition for improved compression. For example, when an ordinary RGB digital image is compressed via the JPEG standard, the RGB colorspace is first converted to a YCbCr colorspace, because the three components in that space have less correlation redundancy and because the chrominance components can be subsampled by a factor of 2 or 4 to further compress the image.
On decompression, the Y′CbCr space is rotated back to RGB. Luma Chroma subsampling
CCIR System H
CCIR System H is an analog broadcast television system used in Belgium, the Balkans and Malta on the UHF bands. Some of the important specs are listed below. A frame is the total picture; the frame rate is the number of pictures displayed in one second. But each frame is scanned twice interleaving odd and lines; each scan is known as a field So field rate is twice the frame rate. In each frame there are 625 lines So line rate 625 • 25 = 15625 Hz; the RF parameters of the transmitted signal are the same as those for System B, used on the 7.0 MHz wide channels of the VHF bands. The only difference to the RF spectrum of the signal is that the vestigial sideband is 500 kHz wider at 1.25 MHz. Due to this and the extra width of the channel allocations at UHF, the width of the guard band between the channels is 650 kHz. Many countries use a variant of system H, known as System G. System G is similar to system H but the lower side band is 500 kHz narrower; this makes poor use of the 8.0 MHz channels of the UHF bands by increasing the width of the guard-band by 500 kHz to 1.15 MHz.
The advantage is that the RF spectrum of system G is the same as system B, simplifying the band-switching circuitry in VHF/UHF televisions. Broadcast television systems Television transmitter Transposer World Analogue Television Standards and Waveforms Fernsehnormen aller Staaten und Gebiete der Welt
A display device is an output device for presentation of information in visual or tactile form. When the input information, supplied has an electrical signal the display is called an electronic display. Common applications for electronic visual displays are televisions or computer monitors. In the history of display technology, a variety of display devices and technologies have been used. There are various designs for display devices. Several components are common to most display devices. Display, or screen, the portion of the device that displays changeable image Bezel, the area surrounding portion that displays changing information Housing, the enclosure of the display These are the technologies used to create the various displays in use today. Electroluminescent display Liquid crystal display with Light-emitting diode -backlit LCD display Light-emitting diode display OLED display AMOLED display Plasma display Quantum dot display Some displays can show only digits or alphanumeric characters.
They are called segment displays, because they are composed of several segments that switch on and off to give appearance of desired glyph. The segments are single LEDs or liquid crystals, they are used in digital watches and pocket calculators. There are several types: Seven-segment display Fourteen-segment display Sixteen-segment display HD44780 LCD controller a accepted protocol for LCDs. Incandescent filaments Vacuum fluorescent display Cold cathode gas discharge Light-emitting diode Liquid crystal display Physical vane with electromagnetic activation 2-dimensional displays that cover a full area are called video displays, since it is the main modality of presenting video. Full-area 2-dimensional displays are used in, for example: Television set Computer monitors Head-mounted display Broadcast reference monitor Medical monitors Underlying technologies for full-area 2-dimensional displays include: Cathode ray tube display Light-emitting diode display Electroluminescent display Electronic paper, E Ink Plasma display panel Liquid crystal display High-Performance Addressing display Thin-film transistor display Organic light-emitting diode display Digital Light Processing display Surface-conduction electron-emitter display Field emission display Laser TV Carbon nanotubes Quantum dot display Interferometric modulator display Digital microshutter display The multiplexed display technique is used to drive most display devices.
Swept-volume display Varifocal mirror display Emissive volume display Laser display Holographic display Light field displays Ticker tape Split-flap display Flip-disc display Rollsign Tactile electronic displays are intended for the blind. They use electro-mechanical parts to dynamically update a tactile image so that the image may be felt by the fingers. Optacon, using metal rods instead of light in order to convey images to blind people by tactile sensation. Society for Information Display - An international professional organization dedicated to the study of display technology University of Waterloo Stratford Campus - A university that offers students the opportunity to display their work on the school's 3-storey Christie MicroTile wall
CCIR System B
CCIR System B was the 625-line analog broadcast television system which at its peak was the system used in most countries. It is being replaced across part of Asia and Africa by digital broadcasting; the system was developed for VHF band. A frame is the total picture; the frame rate is the number of pictures displayed in one second. But each frame is scanned twice interleaving odd and lines; each scan is known as a field So field rate is twice the frame rate. In each frame there are 625 lines So line rate 625 • 25 = 15625 Hz; the video bandwidth is 5.0 MHz. The video signal modulates the carrier by Amplitude Modulation, but a portion of the lower side band is suppressed. This technique is known as vestigial side band modulation; the polarity of modulation is negative, meaning that an increase in the instantaneous brightness of the video signal results in a decrease in RF power and vice versa. The sync pulses result in maximum power from the transmitter; the primary audio signal is modulated by Frequency modulation with a preemphasis time constant of τ = 50 μs.
The deviation for a 1.0 kHz. AF signal is 50 kHz; the separation between the primary audio FM subcarrier and the video carrier is 5.5 MHz. The total RF bandwidth of System B was 6.5 MHz, allowing System B to be transmitted in the 7.0 MHz wide channels specified for television in the VHF bands with an ample 500 kHz guard zone between channels. In specs, other parameters such as vestigial sideband characteristics and gamma of display device are given. System B has variously been used with both the SECAM colour systems, it could have been used with a 625-line variant of the NTSC color system, but apart from possible technical tests in the 1950s, this has never been done officially. When used with PAL, the colour subcarrier is 4.43361875 MHz and the sidebands of the PAL signal have to be truncated on the high-frequency side at +570 kHz. On the low-frequency side, the full 1.3 MHz sideband is radiated. When used with SECAM, the'R' lines' carrier is at 4.40625 MHz deviating from +350±18 kHz to -506±25 kHz.
The'B' lines' carrier is at 4.250 MHz deviating +506±25 kHz to -350±18 kHz. Neither colour encoding system has any effect on the bandwidth of system B as a whole. Enhancements have been made to the specification of System B's audio capabilities over the years; the introduction of Zweiton in the 1970s allowed for stereo sound or twin monophonic audio tracks. This was implemented by adding a second FM audio subcarrier at +5.74 MHz. Alternatively, starting in the late 1980s and early 1990s it became possible to replace the second audio FM subcarrier with a digital signal carrying NICAM sound. Either of these extensions to audio capability have eaten into the guard band between channels. Zweiton uses an extra 150 kHz; the alternative NICAM system uses an extra 500 kHz, needs to be spaced further from the primary audio subcarrier, thus System B with NICAM has only 150 kHz guard zones between channels. System B was the first internationally accepted 625-line broadcasting standard in the world; the European 41-68 MHz Band I television allocation was agreed at the 1947 ITU conference in 1947, the first European channel plan was agreed in 1952 at the ITU conference in Stockholm.
The extension to VHF Band III was agreed in the 1950s. Since the System B specification has been used with different broadcast frequencies in many other countries. † Channel 1 was never used. § Not used in the former East Germany Transmitters were operational on the above channels in 1959. During the 1960s, channels 1 to 3 were deleted and channels E3 to E12 adopted, bringing East Germany into line with the channel allocations used in the West. Italian channel-spacings were erratic. System B is no longer in use in Italy, the switchover to DVB-T having been completed 4 July 2012. Note: Band I is no longer used for television in Italy. Note: Unusually for Europe, Band III is used for DVB-T in Italy. At digital switchover time, Italy took the opportunity to discontinue their erratic System B frequencies, the digital channels are regularly-spaced every 7.0 MHz from 177.5 MHz. Australia were unique in the world by their use of Band II for television broadcasting. ‡ Channels 3, 4 and 5 were scheduled to be cleared during 1993-96 to make way for FM radio stations in Band II.
This clearance action took much longer than was anticipated, as a result, many stations on channel 3 still remain, along with a few on 4 and 5. ♦ New channel allocations from 1993. ‡ Channels 10 and 11 were shifted up in frequency by 1 MHz to make room for channel 9A. The frequencies of existing stations did not change. Digital multiplexes on channels 10 and 11 are using the new channel boundaries. Australia are nearly unique in the world for their use of 7 MHz channel-spacing on UHF. † Added in the 1980s ‡ Added in the 1990s Note: the Band III frequencies are the same as Australia's. When the UHF bands came into use in the early 1960s, two variants of System B began to be used on those frequencies. In most countries, the channels on the UHF bands are
Super Nintendo Entertainment System
The Super Nintendo Entertainment System known as the Super NES or Super Nintendo, is a 16-bit home video game console developed by Nintendo, released in 1990 in Japan and South Korea, 1991 in North America, 1992 in Europe and Australasia, 1993 in South America. In Japan, the system is called the Super Famicom. In South Korea, it was distributed by Hyundai Electronics; the system was released in Brazil on August 1993, by Playtronic. Although each version is the same, several forms of regional lockout prevent the different versions from being compatible with one another; the SNES is Nintendo's second programmable home console, following the Nintendo Entertainment System. The console introduced advanced graphics and sound capabilities compared with other systems at the time; the development of a variety of enhancement chips integrated in game cartridges helped to keep it competitive in the marketplace. The SNES was a global success, becoming the best-selling console of the 16-bit era despite its late start and the intense competition it faced in North America and Europe from Sega's Genesis console.
The SNES remained popular well into the 32-bit era having sold 49.1 million worldwide by the time it was discontinued in 2003.. It continues to be popular among collectors and retro gamers, some of whom still make homebrew ROM images, in addition to its popularity in Nintendo's emulated rereleases, such as on the Virtual Console and the Super NES Classic Edition. To compete with the popular Family Computer in Japan, NEC Home Electronics launched the PC Engine in 1987, Sega followed suit with the Mega Drive in 1988; the two platforms were launched in North America in 1989 as the TurboGrafx-16 and the Sega Genesis, respectively. Both systems were built on 16-bit architectures and offered improved graphics and sound over the 8-bit NES. However, it took several years for Sega's system to become successful. Nintendo executives were in no rush to design a new system, but they reconsidered when they began to see their dominance in the market slipping. Designed by Masayuki Uemura, the designer of the original Famicom, the Super Famicom was released in Japan on Wednesday, November 21, 1990 for 25,000 yen.
It was an instant success. The system's release gained the attention of the Yakuza, leading to a decision to ship the devices at night to avoid robbery. With the Super Famicom outselling its rivals, Nintendo reasserted itself as the leader of the Japanese console market. Nintendo's success was due to the retention of most of its key third-party developers, including Capcom, Tecmo, Square and Enix. Nintendo released the Super Nintendo Entertainment System, a redesigned version of the Super Famicom, in North America for $199, it began shipping in limited quantities on August 23, 1991, with an official nationwide release date of September 9, 1991. The SNES was released in the United Kingdom and Ireland in April 1992 for £150, with a German release following a few weeks later. Most of the PAL region versions of the console use the Japanese Super Famicom design, except for labeling and the length of the joypad leads; the Playtronic Super NES in Brazil, although PAL-M, uses the North American design.
Both the NES and SNES were released in Brazil in 1993 by Playtronic, a joint venture between the toy company Estrela and consumer electronics company Gradiente. The SNES and Super Famicom launched with few games, but these games were well received in the marketplace. In Japan, only two games were available: Super Mario World and F-Zero. In North America, Super Mario World launched as a bundle with the console; the rivalry between Nintendo and Sega resulted in what has been described as one of the most notable console wars in video game history, in which Sega positioned the Genesis as the "cool" console, with games aimed at older audiences, advertisements that attacked the competition. Nintendo however, scored an early public relations advantage by securing the first console conversion of Capcom's arcade classic Street Fighter II for SNES, which took over a year to make the transition to the Genesis. Despite the Genesis's head start, much larger library of games, lower price point, the Genesis only represented an estimated 60% of the American 16-bit console market in June 1992, neither console could maintain a definitive lead for several years.
Donkey Kong Country is said to have helped establish the SNES's market prominence in the latter years of the 16-bit generation, for a time, maintain against the PlayStation and Saturn. According to Nintendo, the company had sold more than 20 million SNES units in the U. S. According to a 2014 Wedbush Securities report based on NPD sales data, the SNES outsold the Genesis in the U. S. market. During the NES era, Nintendo maintained exclusive control over games released for the system—the company had to approve every game, each third-party developer could only release up to five games per year, those games could not be released on another console within two years, Nintendo was the exclusive manufacturer and supplier of NES cartridges
Color television is a television transmission technology that includes information on the color of the picture, so the video image can be displayed in color on the television set. It is an improvement on the earliest television technology, monochrome or black and white television, in which the image is displayed in shades of gray. Television broadcasting stations and networks in most parts of the world upgraded from black and white to color transmission in the 1970s and 1980s; the invention of color television standards is an important part of the history of television, it is described in the technology of television article. Transmission of color images using mechanical scanners had been conceived as early as the 1880s. A practical demonstration of mechanically-scanned color television was given by John Logie Baird in 1928, but the limitations of a mechanical system were apparent then. Development of electronic scanning and display made an all-electronic system possible. Early monochrome transmission standards were developed prior to the Second World War, but civilian electronics developments were frozen during much of the war.
In August 1944, Baird gave the world's first demonstration of a practical electronic color television display. In the United States, commercially competing color standards were developed resulting in the NTSC standard for color that retained compatibility with the prior monochrome system. Although the NTSC color standard was proclaimed in 1953 and limited programming became available, it was not until the early 1970s that color television in North America outsold black and white or monochrome units. Color broadcasting in Europe was not standardized on the SECAM formats until the 1960s. Broadcasters began to switch from analog color television technology to digital television around 2006; this changeover is now complete in many countries, but analog television is still the standard elsewhere. The human eye's detection system, in the retina, consists of two types of light detectors: rod cells that capture light and shapes/figures, the cone cells that detect color. A typical retina contains 120 million rods and 4.5 million to 6 million cones, which are divided among three groups that are sensitive to red and blue light.
This means that the eye has far more resolution in "luminance", than in color. However, post-processing of the optic nerve and other portions of the human visual system combine the information from the rods and cones to re-create what appears to be a high-resolution color image; the eye has limited bandwidth to the rest of the visual system, estimated at just under 8 Mbit/s. This manifests itself in a number of ways, but the most important in terms of producing moving images is the way that a series of still images displayed in quick succession will appear to be continuous smooth motion; this illusion starts to work at about 16 frame/s, common motion pictures use 24 frame/s. Television, using power from the electrical grid, tunes its rate in order to avoid interference with the alternating current being supplied – in North America, some Central and South American countries, Korea, part of Japan, the Philippines, a few other countries, this is 60 video fields per second to match the 60 Hz power, while in most other countries it is 50 fields per second to match the 50 Hz power.
In its most basic form, a color broadcast can be created by broadcasting three monochrome images, one each in the three colors of red and blue. When displayed together or in rapid succession, these images will blend together to produce a full-color image as seen by the viewer. One of the great technical challenges of introducing color broadcast television was the desire to conserve bandwidth three times that of the existing black-and-white standards, not use an excessive amount of radio spectrum. In the United States, after considerable research, the National Television Systems Committee approved an all-electronic system developed by RCA which encoded the color information separately from the brightness information and reduced the resolution of the color information in order to conserve bandwidth; the brightness image remained compatible with existing black-and-white television sets at reduced resolution, while color televisions could decode the extra information in the signal and produce a limited-resolution color display.
The higher resolution black-and-white and lower resolution color images combine in the eye to produce a high-resolution color image. The NTSC standard represented a major technical achievement. Experiments in television systems using radio broadcasts date to the 19th century, but it was not until the 20th century that advances in electronics and light detectors made development practical. A key problem was the need to convert a 2D image into a "1D" radio signal. Early systems used a device known as a "Nipkow disk", a spinning disk with a series of holes punched in it that caused a spot to scan across and down the image. A single photodetector behind the disk captured the image brightness at any given spot, converted into a radio signal and broadcast. A similar disk was used at the receiver side, with a light source behind the disk instead of a detector. A number of such systems were being used experimentally in the 1920s; the best-known was John Logie Baird's, used for regular public broadcasting in Britain for several years.
Indeed, Baird's system was demonstrated to members of the Royal Institution in London in 1926 in what is recognized as the first demonstration of a true, working television system. In spite of these early successes, all mechanical television systems sh