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52-451: The 8 Scanimate systems were used to produce much of the video -based animation seen on television between most of the 1970s and early 1980s in commercials, promotions, and show openings. One of the major advantages the Scanimate system had over film -based animation and computer animation was the ability to create animations in real time . The speed with which animation could be produced on

104-459: A closed-circuit system as an analog signal. Broadcast or studio cameras use a single or dual coaxial cable system using serial digital interface (SDI). See List of video connectors for information about physical connectors and related signal standards. Video may be transported over networks and other shared digital communications links using, for instance, MPEG transport stream , SMPTE 2022 and SMPTE 2110 . Digital television broadcasts use

156-494: A conventional image focusing device (lens, dark box , etc.). Another advantage is that the receiving device is very similar to the acquisition device, except that the light-sensitive device is replaced by a variable light source, driven by the signal provided by the acquisition device. Some means of synchronizing the disks on the two devices must also be devised (several options are possible, ranging from manual to electronic control signals). These facts helped immensely in building

208-465: A great deal of flickering. The acquisition part of the system was not much better, requiring very powerful lighting of the subject. Disk scanners share a major limitation with the Farnsworth image dissector . Light is conveyed into the sensing system as the small aperture scans over the entire field of view. The actual amount of light gathered is instantaneous, occurring through a very small aperture, and

260-405: A larger image. When spinning the disk while observing an object "through" the disk, preferably through a relatively small circular sector of the disk (the viewport ), for example, an angular quarter or eighth of the disk, the object seems "scanned" line by line, first by length or height or even diagonally, depending on the exact sector chosen for observation. By spinning the disk rapidly enough,

312-433: A natively progressive broadcast or recorded signal, the result is the optimum spatial resolution of both the stationary and moving parts of the image. Interlacing was invented as a way to reduce flicker in early mechanical and CRT video displays without increasing the number of complete frames per second . Interlacing retains detail while requiring lower bandwidth compared to progressive scanning. In interlaced video,

364-442: A number is available. Analog video is a video signal represented by one or more analog signals . Analog color video signals include luminance (Y) and chrominance (C). When combined into one channel, as is the case among others with NTSC , PAL , and SECAM , it is called composite video . Analog video may be carried in separate channels, as in two-channel S-Video (YC) and multi-channel component video formats. Analog video

416-438: A particular refresh rate, display resolution , and color space . Many analog and digital recording formats are in use, and digital video clips can also be stored on a computer file system as files, which have their own formats. In addition to the physical format used by the data storage device or transmission medium, the stream of ones and zeros that is sent must be in a particular digital video coding format , for which

468-433: A photoconductive plate with the desired image and produce a voltage signal proportional to the brightness in each part of the image. The signal could then be sent to televisions, where another beam would receive and display the image. Charles Ginsburg led an Ampex research team to develop one of the first practical video tape recorders (VTR). In 1951, the first VTR captured live images from television cameras by writing

520-402: A postage-stamp in the case of a 30 to 50 cm diameter disk. Further disadvantages include the non-linear geometry of the scanned images, and the impractical size of the disk, at least in the past. The Nipkow disks used in early TV receivers were roughly 30 cm to 50 cm in diameter, with 30 to 50 holes. The devices using them were also noisy and heavy with very low picture quality and

572-507: A ratio between width and height. The ratio of width to height for a traditional television screen is 4:3, or about 1.33:1. High-definition televisions use an aspect ratio of 16:9, or about 1.78:1. The aspect ratio of a full 35 mm film frame with soundtrack (also known as the Academy ratio ) is 1.375:1. Pixels on computer monitors are usually square, but pixels used in digital video often have non-square aspect ratios, such as those used in

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624-429: A single photocell or photodiode , since at each instant only a very small area is visible through the disk (and viewport), and so decomposing an image into lines is done almost by itself with little need for scanline timing, and very high scanline resolution . A simple acquisition device can be built by using an electrical motor driving a Nipkow disk, a small box containing a single light-sensitive (electric) element and

676-564: Is extremely fluid, using all 60 fields per second (in NTSC format video) or 50 fields (in PAL format video) rather than the 24 frames per second that film uses; the colors are much brighter and more saturated; and the images have a very "electronic" look that results from the direct manipulation of video signals through which the Scanimate produces the images. A special high-resolution (around 945 lines) monochrome camera records high-contrast artwork. The image

728-456: Is in rough chronological order. All formats listed were sold to and used by broadcasters, video producers, or consumers; or were important historically. Digital video tape recorders offered improved quality compared to analog recorders. Optical storage mediums offered an alternative, especially in consumer applications, to bulky tape formats. A video codec is software or hardware that compresses and decompresses digital video . In

780-455: Is less sensitive to details in color than brightness, the luminance data for all pixels is maintained, while the chrominance data is averaged for a number of pixels in a block, and the same value is used for all of them. For example, this results in a 50% reduction in chrominance data using 2-pixel blocks (4:2:2) or 75% using 4-pixel blocks (4:2:0). This process does not reduce the number of possible color values that can be displayed, but it reduces

832-517: Is often described as 576i50 , where 576 indicates the total number of horizontal scan lines, i indicates interlacing, and 50 indicates 50 fields (half-frames) per second. When displaying a natively interlaced signal on a progressive scan device, the overall spatial resolution is degraded by simple line doubling —artifacts, such as flickering or "comb" effects in moving parts of the image that appear unless special signal processing eliminates them. A procedure known as deinterlacing can optimize

884-527: Is reduced by registering differences between parts of a single frame; this task is known as intraframe compression and is closely related to image compression . Likewise, temporal redundancy can be reduced by registering differences between frames; this task is known as interframe compression , including motion compensation and other techniques. The most common modern compression standards are MPEG-2 , used for DVD , Blu-ray, and satellite television , and MPEG-4 , used for AVCHD , mobile phones (3GP), and

936-422: Is shot at a slower frame rate of 24 frames per second, which slightly complicates the process of transferring a cinematic motion picture to video. The minimum frame rate to achieve a comfortable illusion of a moving image is about sixteen frames per second. Video can be interlaced or progressive . In progressive scan systems, each refresh period updates all scan lines in each frame in sequence. When displaying

988-492: Is that decompressed video has lower quality than the original, uncompressed video because there is insufficient information to accurately reconstruct the original video. Nipkow disk A Nipkow disk (sometimes Anglicized as Nipkov disk; patented in 1884), also known as scanning disk , is a mechanical, rotating, geometrically operating image scanning device, patented by Paul Gottlieb Nipkow in Berlin . This scanning disk

1040-462: Is that the output of the Scanimate itself is always monochrome. Another advantage of the colorizer is that it gives the operator the ability to continuously add layers of graphics. This makes possible the creation of very complex graphics. This is done by using two video recorders. The background is played by one recorder and then recorded by another one. This process is repeated for every layer. This requires very high-quality video recorders (such as both

1092-467: Is the last one produced and is being kept in its original configuration for historical purposes by David Sieg at ZFx inc. The machines are installed in a working production environment with Grass Valley switchers, Kaleidoscope digital video effects systems and Accom digital disk recorders for layering. Video Video is an electronic medium for the recording, copying , playback, broadcasting , and display of moving visual media . Video

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1144-473: Is then displayed on a high-resolution screen. Unlike a normal monitor, its deflection signals are passed through a special analog computer that enables the operator to bend the image in a variety of ways. The image is then shot from the screen by either a film camera or a video camera. In the case of a video camera, this signal is then fed into a colorizer, a device that takes certain shades of grey and turns it into color as well as transparency. The idea behind this

1196-502: Is used in NTSC television, YUV is used in PAL television, YDbDr is used by SECAM television, and YCbCr is used for digital video. The number of distinct colors a pixel can represent depends on the color depth expressed in the number of bits per pixel. A common way to reduce the amount of data required in digital video is by chroma subsampling (e.g., 4:4:4, 4:2:2, etc.). Because the human eye

1248-440: Is used in both consumer and professional television production applications. Digital video signal formats have been adopted, including serial digital interface (SDI), Digital Visual Interface (DVI), High-Definition Multimedia Interface (HDMI) and DisplayPort Interface. Video can be transmitted or transported in a variety of ways including wireless terrestrial television as an analog or digital signal, coaxial cable in

1300-671: The Ampex VR-2000 or IVC 's IVC-9000 of Scanimate's era, the IVC-9000 being used quite frequently for Scanimate composition due to its very high generational quality between re-recordings). Two of the Scanimates are still in use at ZFx studios in Asheville, NC. The original "Black Swan" R&D machine has been updated with more modern power supplies and can produce material in standard or 1080P high definition video. The "white Pearl" machine

1352-494: The Latin video (I see). Video developed from facsimile systems developed in the mid-19th century. Early mechanical video scanners, such as the Nipkow disk , were patented as early as 1884, however, it took several decades before practical video systems could be developed, many decades after film . Film records using a sequence of miniature photographic images visible to the eye when

1404-499: The MPEG-2 and other video coding formats and include: Analog television broadcast standards include: An analog video format consists of more information than the visible content of the frame. Preceding and following the image are lines and pixels containing metadata and synchronization information. This surrounding margin is known as a blanking interval or blanking region ; the horizontal and vertical front porch and back porch are

1456-463: The Internet. Stereoscopic video for 3D film and other applications can be displayed using several different methods: Different layers of video transmission and storage each provide their own set of formats to choose from. For transmission, there is a physical connector and signal protocol (see List of video connectors ). A given physical link can carry certain display standards that specify

1508-452: The Nipkow disk as an image scanning device: the scanlines are not straight lines, but rather curves . So the ideal Nipkow disk should have either a very large diameter, which means smaller curvature , or a very narrow angular opening of its viewport. Another way to produce acceptable images would be to drill smaller holes (millimeter or even micrometer scale) closer to the outer sectors of

1560-489: The PAL and NTSC variants of the CCIR 601 digital video standard and the corresponding anamorphic widescreen formats. The 720 by 480 pixel raster uses thin pixels on a 4:3 aspect ratio display and fat pixels on a 16:9 display. The popularity of viewing video on mobile phones has led to the growth of vertical video . Mary Meeker , a partner at Silicon Valley venture capital firm Kleiner Perkins Caufield & Byers , highlighted

1612-450: The building blocks of the blanking interval. Computer display standards specify a combination of aspect ratio, display size, display resolution, color depth, and refresh rate. A list of common resolutions is available. Early television was almost exclusively a live medium, with some programs recorded to film for historical purposes using Kinescope . The analog video tape recorder was commercially introduced in 1951. The following list

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1664-425: The camera's electrical signal onto magnetic videotape . Video recorders were sold for $ 50,000 in 1956, and videotapes cost US$ 300 per one-hour reel. However, prices gradually dropped over the years; in 1971, Sony began selling videocassette recorder (VCR) decks and tapes into the consumer market . Digital video is capable of higher quality and, eventually, a much lower cost than earlier analog technology. After

1716-553: The commercial introduction of the DVD in 1997 and later the Blu-ray Disc in 2006, sales of videotape and recording equipment plummeted. Advances in computer technology allow even inexpensive personal computers and smartphones to capture, store, edit, and transmit digital video, further reducing the cost of video production and allowing programmers and broadcasters to move to tapeless production . The advent of digital broadcasting and

1768-438: The context of video compression, codec is a portmanteau of encoder and decoder , while a device that only compresses is typically called an encoder , and one that only decompresses is a decoder . The compressed data format usually conforms to a standard video coding format . The compression is typically lossy , meaning that the compressed video lacks some information present in the original video. A consequence of this

1820-399: The disk and proceeding to the center of the disk. When the disk rotates, the holes trace circular ring patterns, with inner and outer diameter depending on each hole's position on the disk and thickness equal to each hole's diameter. The patterns may or may not partially overlap, depending on the exact construction of the disk. A lens projects an image of the scene in front of it directly onto

1872-407: The disk, but technological evolution favoured electronic means of image acquisition. Another significant disadvantage lay with reproducing images at the receiving end of the transmission which was also accomplished with a Nipkow disk. The images were typically very small, as small as the surface used for scanning, which, with the practical implementations of mechanical television , were the size of

1924-421: The disk. Each hole in the spiral takes a "slice" through the image which is picked up as a temporal pattern of light and dark by a sensor. If the sensor is made to control a light behind a second Nipkow disk rotating synchronously at the same speed and in the same direction, the image will be reproduced line-by-line. The size of the reproduced image is again determined by the size of the disc; a larger disc produces

1976-509: The display of an interlaced video signal from an analog, DVD, or satellite source on a progressive scan device such as an LCD television , digital video projector , or plasma panel. Deinterlacing cannot, however, produce video quality that is equivalent to true progressive scan source material. Aspect ratio describes the proportional relationship between the width and height of video screens and video picture elements. All popular video formats are rectangular , and this can be described by

2028-445: The fields one at a time, rather than dividing up a complete frame after it is captured, the frame rate for motion is effectively doubled as well, resulting in smoother, more lifelike reproduction of rapidly moving parts of the image when viewed on an interlaced CRT display. NTSC, PAL, and SECAM are interlaced formats. Abbreviated video resolution specifications often include an i to indicate interlacing. For example, PAL video format

2080-441: The film is physically examined. Video, by contrast, encodes images electronically, turning the images into analog or digital electronic signals for transmission or recording. Video technology was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) television systems. Video was originally exclusively live technology. Live video cameras used an electron beam, which would scan

2132-555: The first mechanical television accomplished by the Scottish inventor John Logie Baird , as well as the first "TV-Enthusiasts" communities and even experimental image radio broadcasts in the 1920s. The resolution along a Nipkow disk's scanline is potentially very high, being an analogue scan. However the maximum number of scanlines is much more limited, being equal to the number of holes on the disk, which in practice ranged from 30 to 100, with rare 200-hole disks tested. Another drawback of

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2184-466: The growth of vertical video viewing in her 2015 Internet Trends Report – growing from 5% of video viewing in 2010 to 29% in 2015. Vertical video ads like Snapchat 's are watched in their entirety nine times more frequently than landscape video ads. The color model uses the video color representation and maps encoded color values to visible colors reproduced by the system. There are several such representations in common use: typically, YIQ

2236-432: The horizontal scan lines of each complete frame are treated as if numbered consecutively and captured as two fields : an odd field (upper field) consisting of the odd-numbered lines and an even field (lower field) consisting of the even-numbered lines. Analog display devices reproduce each frame, effectively doubling the frame rate as far as perceptible overall flicker is concerned. When the image capture device acquires

2288-446: The net yield is only a microscopic percentage of the incident energy. Iconoscopes (and their successors) accumulate energy on the target continuously, thereby integrating energy over time. The scanning system simply "picks off" the accumulated charge as it sweeps past each site on the target. Simple calculations show that, for equally sensitive photosensitive receptors, the iconoscope is hundreds to thousands of times more sensitive than

2340-622: The number of distinct points at which the color changes. Video quality can be measured with formal metrics like peak signal-to-noise ratio (PSNR) or through subjective video quality assessment using expert observation. Many subjective video quality methods are described in the ITU-T recommendation BT.500 . One of the standardized methods is the Double Stimulus Impairment Scale (DSIS). In DSIS, each expert views an unimpaired reference video, followed by an impaired version of

2392-422: The object seems complete and capturing of motion becomes possible. This can be intuitively understood by covering all of the disk but a small rectangular area with black cardboard (which stays fixed), spinning the disk and observing an object through the small area. One of the advantages of using a Nipkow disk is that the image sensor (that is, the device converting light to electric signals) can be as simple as

2444-436: The same video. The expert then rates the impaired video using a scale ranging from "impairments are imperceptible" to "impairments are very annoying." Uncompressed video delivers maximum quality, but at a very high data rate . A variety of methods are used to compress video streams, with the most effective ones using a group of pictures (GOP) to reduce spatial and temporal redundancy . Broadly speaking, spatial redundancy

2496-455: The subsequent digital television transition are in the process of relegating analog video to the status of a legacy technology in most parts of the world. The development of high-resolution video cameras with improved dynamic range and color gamuts , along with the introduction of high-dynamic-range digital intermediate data formats with improved color depth , has caused digital video technology to converge with film technology. Since 2013,

2548-464: The system because of this, as well as its range of possible effects, helped it to supersede film-based animation techniques for television graphics. By the mid-1980s, it was superseded by digital computer animation , which produced sharper images and more sophisticated 3D imagery. Animations created on Scanimate and similar analog computer animation systems have a number of characteristic features that distinguish them from film-based animation: The motion

2600-562: The use of digital cameras in Hollywood has surpassed the use of film cameras. Frame rate , the number of still pictures per unit of time of video, ranges from six or eight frames per second ( frame/s ) for old mechanical cameras to 120 or more frames per second for new professional cameras. PAL standards (Europe, Asia, Australia, etc.) and SECAM (France, Russia, parts of Africa, etc.) specify 25 frame/s, while NTSC standards (United States, Canada, Japan, etc.) specify 29.97 frame/s. Film

2652-461: Was a fundamental component in mechanical television , and thus the first televisions , through the 1920s and 1930s. The device is a mechanically spinning disk of any suitable material (metal, plastic, cardboard, etc.), with a series of equally-distanced circular holes of equal diameter drilled in it. The holes may also be square for greater precision. These holes are positioned to form a single-turn spiral starting from an external radial point of

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2704-526: Was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems, which, in turn, were replaced by flat-panel displays of several types. Video systems vary in display resolution , aspect ratio , refresh rate , color capabilities, and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcasts , magnetic tape , optical discs , computer files , and network streaming . The word video comes from

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