EIAJ-1 was a standard for video tape recorders developed by the Electronic Industries Association of Japan with the cooperation and assistance of several Japanese electronics manufacturers in 1969. It was the first standardized format for industrial/non-broadcast VTRs using a Helical scan system employing open reel tape; each manufacturer of machines in this market used a different proprietary format, with differing tape speeds, scanner drum diameters, bias frequencies, tracking head placement, so on, although most used 1/2" wide tape. As a result, video tapes recorded on one make and/or model of VTR could only be interchanged with other machines using that specific format, hampering compatibility. For example, a reel of tape recorded on a Panasonic machine would not play on a Sony machine, vice versa; the EIAJ-1 standard ended this incompatibility, giving those manufacturers a standardized format, interchangeable with all VTRs subsequently brought to market around that time. The format offered black-and-white video recording and playback on 1/2" magnetic tape on a 7" diameter open reel, with portable units using smaller 5" diameter reels.
The EIAJ-1 standard paved the way for consumer oriented non-professional analog video recording technology to become more affordable and widespread, with many businesses, government agencies and some consumers adopting the format in the early 1970s. Some of the first public-access television cable stations that started up around that time used EIAJ-1 equipment extensively, due to its portability, low cost, versatility; the original Sony Portapak, model CV-2000, used a proprietary format, but was superseded by an EIAJ-1 compatible version, the AV-3400. When EIAJ-1 was standardized, no videocassette recorders had yet been introduced. One of the main drawbacks to the format was the need to thread the end of the tape around the head drum, through a gap between the capstan and pinch roller, around a variety of guides and tensioners. If the user made any errors in doing this, the machine would malfunction and the tape could become damaged. So, another version, EIAJ-2, was released on that used a single-reel cartridge instead of an open take up reel.
Otherwise, the recording specifications were the same. By 1971, Sony introduced the U-matic format; the U-Matic system offered many advantages over EIAJ-1, including color recording as standard, stereo sound, automatic tape threading. However, EIAJ-1 equipment remained popular for a number of years as it was less expensive than U-Matic machines or tape, EIAJ-1 equipment was lighter and more compact, portable battery operated EIAJ-1 machines with companion video cameras were available, it wasn't until the mid 1970s that portable U-Matic machines and compatible portable color cameras were introduced. Neither the EIAJ-1 nor the U-Matic format were used in a Camcorder camera recorder unit, because of the size and weight of the mechanism involved; the recorder and camera were always separate units, connected by a multi conductor cable. The advent of the camcorder did not occur until the introduction of smaller, lighter cassette formats, such as Betamax and VHS. Information & specifications on EIAJ-1 DC Video 1/2 VTR page Video interchange change video history on EIAJ 1/2" Half Inch Open Reel Video Tape Information & specifications on Sony EIAJ-1 Experimental Television Center - Panasonic 1/2" specs Experimental Television Center - Sony AV-3400 Portapak Sony CV Series Video information
DV is a format for storing digital video. It was launched in 1995 with joint efforts of leading producers of video camera recorders; the original DV specification, known as Blue Book, was standardized within the IEC 61834 family of standards. These standards define common features such as physical videocassettes, recording modulation method and basic system data in part 1. Part 2 describes the specifics of 625-50 systems; the IEC standards are available as publications sold by IEC and ANSI. In 2003, DV was joined by a successor format HDV, which used the same tape format with a different video codec; some cameras at the time had the ability to switch between HDV recording modes. All tape-based video formats are becoming obsolete as tapeless HD cameras recording on memory cards, hard disk drives, solid-state drives, optical discs have become the norm, although the DV encoding standard is sometimes still used in tapeless cameras. DV uses lossy compression of video. An intraframe video compression scheme is used to compress video on a frame-by-frame basis with the discrete cosine transform.
Following ITU-R Rec. 601 standard, DV video employs interlaced scanning with the luminance sampling frequency of 13.5 MHz. These results in 480 scanlines per complete frame for the 60 Hz system, 576 scanlines per complete frame for the 50 Hz system. In both systems the active area contains 720 pixels per scanline, with 704 pixels used for content and 16 pixels on the sides left for digital blanking; the same frame size is used for 4:3 and 16:9 frame aspect ratios, resulting in different pixel aspect ratios for fullscreen and widescreen video. Prior to the DCT compression stage, chroma subsampling is applied to the source video in order to reduce the amount of data to be compressed. Baseline DV uses 4:2:0 subsampling in the 50 Hz variant. Low chroma resolution of DV is a reason this format is sometimes avoided in chroma keying applications, though advances in chroma keying techniques and software have made producing quality keys from DV material possible. Audio can be stored in either of two forms: 16-bit Linear PCM stereo at 48 kHz sampling rate, or four nonlinear 12-bit PCM channels at 32 kHz sampling rate.
In addition, the DV specification supports 16-bit audio at 44.1 kHz, the same sampling rate used for CD audio. In practice, the 48 kHz stereo mode is used exclusively; the audio and metadata are packaged into 80-byte Digital Interface Format blocks which are multiplexed into a 150-block sequence. DIF blocks are the basic units of DV streams and can be stored as computer files in raw form or wrapped in such file formats as Audio Video Interleave, QuickTime and Material Exchange Format. One video frame is formed from either 10 or 12 such sequences, depending on scanning rate, which results in a data rate of about 25 Mbit/s for video, an additional 1.5 Mbit/s for audio. When written to tape, each sequence corresponds to one complete track. Baseline DV employs unlocked audio; this means. However, this is the maximum drift of the audio/video synchronization. Sony and Panasonic created their proprietary versions of DV aimed toward professional & broadcast users, which use the same compression scheme, but improve on robustness, linear editing capabilities, color rendition and raster size.
All DV variants. Film-like frame rates are possible by using pulldown. DVCPRO HD supports native progressive format. DVCPRO known as DVCPRO25, is a variation of DV developed by Panasonic and introduced in 1995 for use in electronic news gathering equipment. Unlike baseline DV, DVCPRO uses locked audio and 4:1:1 chroma subsampling for both 50 Hz and 60 Hz variants to decrease generation losses. Audio is available in 16-bit/48 kHz precision; when recorded to tape, DVCPRO uses wider track pitch - 18 μm vs. 10 μm of baseline DV, which reduces the chance of dropout errors during recording. Two extra longitudinal tracks provide support for timecode control. Tape is transported 80% faster compared to baseline DV, resulting in shorter recording time. Long Play mode is not available. In 1996 Sony responded with its own professional version of DV called DVCAM. Like DVCPRO, DVCAM uses locked audio, which prevents audio synchronization drift that may happen on DV if several generations of copies are made; when recorded to tape, DVCAM uses 15 μm track pitch, 50% wider compared to baseline.
Accordingly, tape is transported 50% faster, which reduces recording time by one third compared to regular DV. Because of the wider track and track pitch, DVCAM has the ability to do a frame-accurate insert edit, while regular DV may vary by a few frames on each edit compared to the preview. DVCPRO50 was introduced by Panasonic in 1997 for high-value electronic news gathering and digital cinema, is described as two DV codecs working in parallel; the DVCPRO50 doubles the coded video data rate to 50 Mbit/s. This has the effect of cutting total record time of any given storage medium in half. Chroma resolution is improved by using 4:2:2 chroma subsampling. DVCPRO50 was used in many productions. For example, BBC used DVCPRO50 to record high-budget TV series, such as Space Race and Ancient Rome: The Rise and Fall of an Empire. A similar format, D-9, offered
IVC videotape format
IVC 2 inch Helical scan was a high-end broadcast quality helical scan analog recording VTR format developed by International Video Corporation, introduced in 1975. IVC had made a number of 1 inch Helical VTRs. IVC saw a chance to make a VTR that would have the quality of the then-standard 2 inch Quadruplex videotape format but with the advantages of helical scan, they developed a VTR using this technology, the IVC Model 9000. IVC made the Model 9000 in five versions: IVC 9000 IVC 9000-4 (4 ips tape speed, Long Play, could record and play back 4 hours on one 10.5 inch reel IVC 9000-W IVC 9000-M IVC 9000-W-M The Helical scanner used a tape wrap of 188.57 degrees around a drum of 3.170 inches in diameter, with two play/record heads. In the NTSC version of the format, it had 5 helical tracks per field and 6 in the PAL version, each with 57 lines per segment; the VTR was equipped with a color video monitor, a waveform monitor scope, vectorscope. All models had: Two analog audio channels One cue track One control track Time code track Capstan-driven tape speed of 8 inches per second Analog color timebase corrector Dropout compensation Other Spec: Vacuum tape tension columns Vacuum grip capstan Weight of 1300 pounds Power feed of 230 V at 3000 watts One second lock up time, stop to play a 1500-hour head warranty Signal-to-noise ratio > 48 dB The 9000 was one of the first analog video recorders utilized for electronic film production using analog high-resolution wideband video standards, predating DI film production systems in use today.
The 9000-W-M was, for all purposes, a custom pre-HDTV video system. The 655 line system was used for 24 frame playback on TVs and monitors used on movie studio sets, thus the TVs had no flicker. The 9000-W-M was used for some JAWS 3D's composite special effects; the 9000, in its regular 525-line & 60-field-per-second NTSC configuration, was used for mastering some of the first laserdiscs released by Discovision in 1978 due to the format's high quality. However, Discovision abandoned the format a few years in favor of 1" Type C videotape, due to service & support for the 9000 machines becoming unavailable after IVC went out of business in the early 80s, due to the growing industry support for the newer 1" Type C format; the picture quality was excellent, but the IVC-9000 did not have many sales. Shortly after it came out, both the 1" Type B and 1" Type. Both used less costly tape, made just about as good of a picture. Ampex in 1961 made a 2 inch helical scan VTR for a short time, the VR-8000, they produced another 2" helical VTR, the VR-660, in 1963.
Sony made a 2 inch Helical scan VTR, but it was non-segmented and they sold fewer of them. IVC 800 series 1 Inch VTR was popular. 800 series are reel-to-reel helical'mid band' color portable TVR using 1 inch/25mm tape running at 17.2 cm per second/6.77 inches/second. 1 inch type B videotape 1 inch type C videotape 2 inch Quadruplex videotape Helical scan Videotape VTR lionlamb.us B&W Photo IVC 9000 Lab Guys World IVC Memories Lab Guys World's IVC 9000 DC Video IVC 9000 ionlamb.us IVC VTR list Lab Guys World IVC list Labguysworld.com IVC 9000 page 2 videopreservation.conservation-us.org The Video Guide, The VTR, Chapter 5, page 68, Charles Bensinger 1981
Discrete cosine transform
A discrete cosine transform expresses a finite sequence of data points in terms of a sum of cosine functions oscillating at different frequencies. DCTs are important to numerous applications in science and engineering, from lossy compression of audio and images, to spectral methods for the numerical solution of partial differential equations; the use of cosine rather than sine functions is critical for compression, since it turns out that fewer cosine functions are needed to approximate a typical signal, whereas for differential equations the cosines express a particular choice of boundary conditions. In particular, a DCT is a Fourier-related transform similar to the discrete Fourier transform, but using only real numbers; the DCTs are related to Fourier Series coefficients of a periodically and symmetrically extended sequence whereas DFTs are related to Fourier Series coefficients of a periodically extended sequence. DCTs are equivalent to DFTs of twice the length, operating on real data with symmetry, whereas in some variants the input and/or output data are shifted by half a sample.
There are eight standard DCT variants. The most common variant of discrete cosine transform is the type-II DCT, called "the DCT", its inverse, the type-III DCT, is correspondingly called "the inverse DCT" or "the IDCT". Two related transforms are the discrete sine transform, equivalent to a DFT of real and odd functions, the modified discrete cosine transform, based on a DCT of overlapping data. Multidimensional DCTs are developed to extend the concept of DCT on MD Signals. There are several algorithms to compute MD DCT. A new variety of fast algorithms are developed to reduce the computational complexity of implementing DCT; the DCT, in particular the DCT-II, is used in signal and image processing for lossy compression, because it has a strong "energy compaction" property: in typical applications, most of the signal information tends to be concentrated in a few low-frequency components of the DCT. For correlated Markov processes, the DCT can approach the compaction efficiency of the Karhunen-Loève transform.
As explained below, this stems from the boundary conditions implicit in the cosine functions. A related transform, the modified discrete cosine transform, or MDCT, is used in AAC, Vorbis, WMA, MP3 audio compression. DCTs are widely employed in solving partial differential equations by spectral methods, where the different variants of the DCT correspond to different even/odd boundary conditions at the two ends of the array. DCTs are closely related to Chebyshev polynomials, fast DCT algorithms are used in Chebyshev approximation of arbitrary functions by series of Chebyshev polynomials, for example in Clenshaw–Curtis quadrature; the DCT is used in JPEG image compression, MJPEG, MPEG, DV, Theora video compression. There, the two-dimensional DCT-II of N × N blocks are computed and the results are quantized and entropy coded. In this case, N is 8 and the DCT-II formula is applied to each row and column of the block; the result is an 8 × 8 transform coefficient array in which the element is the DC component and entries with increasing vertical and horizontal index values represent higher vertical and horizontal spatial frequencies.
Multidimensional DCTs have several applications 3-D DCT-II has several new applications like Hyperspectral Imaging coding systems, variable temporal length 3-D DCT coding, video coding algorithms, adaptive video coding and 3-D Compression. Due to enhancement in the hardware and introduction of several fast algorithms, the necessity of using M-D DCTs is increasing. DCT-IV has gained popularity for its applications in fast implementation of real-valued polyphase filtering banks, lapped orthogonal transform and cosine-modulated wavelet bases. Like any Fourier-related transform, discrete cosine transforms express a function or a signal in terms of a sum of sinusoids with different frequencies and amplitudes. Like the discrete Fourier transform, a DCT operates on a function at a finite number of discrete data points; the obvious distinction between a DCT and a DFT is that the former uses only cosine functions, while the latter uses both cosines and sines. However, this visible difference is a consequence of a deeper distinction: a DCT implies different boundary conditions from the DFT or other related transforms.
The Fourier-related transforms that operate on a function over a finite domain, such as the DFT or DCT or a Fourier series, can be thought of as implicitly defining an extension of that function outside the domain. That is, once you write a function f as a sum of sinusoids, you can evaluate that sum at any x for x where the original f was not specified; the DFT, like the Fourier series, implies a periodic extension of the original function. A DCT, like a cosine transform, implies an extension of the original function. However, because DCTs operate on finite, discrete sequences, two issues arise that
MII (videocassette format)
This article discusses the MII video tape format. For information on the game console by Panasonic please see Panasonic M2MII is a professional analog recording videocassette format developed by Panasonic in 1986 in competition with Sony's Betacam SP format, it was technically similar to Betacam SP, using metal-formulated tape loaded in the cassette, utilizing component video recording. MII is sometimes incorrectly referred to as M2. Just as Betacam SP was an improved version of its predecessor Betacam with higher video and audio quality, MII was an enhanced development of its predecessor, the failed M format. There were two sizes of MII tape, the larger of, close to VHS size and has a running time of up to around 90 minutes, the smaller tape was about half the size and runs up to around 20 minutes, was the size in which head cleaner tapes were supplied. Panasonic manufactured mains-powered MII editing and playback decks which accepted both the large and small tapes, as well as portable recorders which used only the small cassette.
Unlike M, MII was somewhat successful when it was first launched, with customers like NBC in the US and NHK in Japan using it for electronic news gathering, PBS in the USA using it in the late 1980s to delay their television network programming by 3 hours on broadcast delay for airing on the West Coast. But MII suffered from lackluster marketing, a lack of customer support and public relations from Panasonic and Matsushita, most a lack of reliability due to said lack of support for repair and service; this resulted in MII not being nearly as successful as Betacam SP. NBC dropped the format in the early 1990s for Panasonic's D3 Format, began broadcasting all of its television programming and television commercials from digital video servers in the 2000s. In the UK, MII was used in early 1990s by three ITV franchisees. Of the three, Thames and TV-am lost their licences in the 1991 ITV franchise auctions, depleting still further the scant MII usage in the country. MII is used nowadays, spare parts as well as tapes for the format are now hard to come by, although used MII equipment can be found cheaply on the professional video equipment market and online auctions.
MII faded earlier than other analog video formats, in favor of digital tapes such as DV, DVCAM and DVCPro, which were themselves superseded by high definition discs and cards. A small number of specialist companies maintain old MII machines in order to offer a transfer service for archive footage to modern formats; the MII format was analog, with four audio channels. Six tracks were recorded on the tape: two by four by the stationary head. Beginning at the top of the tape, the first two tracks were audio channels two and one, recorded linearly by the stationary head. Below these were diagonal tracks recorded by the moving head in a method known as helical scan, which increases the effective tape speed and thus the bandwidth needed for storing video. There were two tracks called carrying frequency modulated video components; the C track contained audio channels three and four, frequency modulated. Below the moving head tracks, the last two tracks carried control and time code information from the stationary head.
The control signal was used to synchronize the moving heads for playback. Video was split among the C and Y tracks: Luminance was frequency modulated and written to the Y track; the two chrominance signals, Pr and Pb, were combined by chrominance time compressed multiplexing, a type of time division multiplexing. The resulting CTCM signal was frequency modulated and combined with the FM audio carriers, written to the C track. M terraguide.com List of Videotape formats, with a mention on MII lionlamb.us List of videotape formats past and present, with a mention of the M format mediacollege.com The M Format ultimatewebdesigning.com List of videotape formats past and present, the M format listed Sony Betamax Case Report DC Video on MII The History of Television, 1942 to 2000, page 194, By Albert Abramson, Christopher H. Sterling Encyclopedia of television, Volume 1, page 251, By Horace Newcomb The History of Television, 1942 to 2000, page 214, By Albert Abramson, Christopher H. Sterling, NBC use
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
Society of Motion Picture and Television Engineers
The Society of Motion Picture and Television Engineers, founded in 1916 as the Society of Motion Picture Engineers or SMPE, is a global professional association, of engineers and executives working in the media and entertainment industry. An internationally recognized standards organization, SMPTE has more than 800 Standards, Recommended Practices, Engineering Guidelines for broadcast, digital cinema, audio recording, information technology, medical imaging. In addition to development and publication of technical standards documents, SMPTE publishes the SMPTE Motion Imaging Journal, provides networking opportunities for its members, produces academic conferences and exhibitions, performs other industry-related functions. SMPTE Membership is open to any individual or organization with interest in the subject matter. SMPTE standards documents are copyrighted and may be purchased from the SMPTE website, or other distributors of technical standards. Standards documents may be purchased by the general public.
Significant standards promulgated by SMPTE include: All film and television transmission formats and media, including digital. Physical interfaces for transmission of television signals and related data SMPTE color bars Test card patterns and other diagnostic tools The Material eXchange Format, or MXF SMPTE ST 2110SMPTE's educational and professional development activities include technical presentations at regular meetings of its local Sections and biennial conferences in the US and Australia and the SMPTE Motion Imaging Journal; the society sponsors many awards, the oldest of which are the SMPTE Progress Medal, the Samuel Warner Memorial Medal, the David Sarnoff Medal. SMPTE has a number of Student Chapters and sponsors scholarships for college students in the motion imaging disciplines. SMPTE is a 5013 non-profit charitable organization. Related organizations include Advanced Television Systems Committee Moving Picture Experts Group Joint Photographic Experts Group ITU Radiocommunication Sector ITU Telecommunication Sector Digital Video Broadcasting BBC Research Department European Broadcasting Union SMPTE's first standard in 1917 was for speed at which film is shown.
SMPTE's Task Force on 3D to the Home produced a report on the issues and suggested minimum standards for the 3D Home Master that would be distributed after post production to the ingest points of distribution channels for 3D video content. A group within the standards committees has begun to work on the formal definition of the SMPTE 3D Home Master. SMPTE, instituted in 1999, a technology committee for the foundations of Digital Cinema: DC28; the SMPTE presents awards to individuals for outstanding contributions in fields of the society. Recipients include: Renville “Ren” H. McMann Jr. James Cameron Oscar B. "O. B." Hanson George Lucas John Logie Baird Philo Taylor Farnsworth Ray M. Dolby Linwood G. Dunn Herbert T. Kalmus Walt Disney Vladimir K. Zworykin Samuel L. Warner George Eastman Thomas Alva Edison Louis Lumiere C. Francis Jenkins The Progress Medal, instituted in 1935, is SMPTE's oldest and most prestigious medal, awarded annually for contributions to engineering aspects of the film and/or television industries.
Recipients include: Douglas Trumbull Ioan Allen David Wood Edwin Catmull Birney Dayton Clyde D. Smith Roderick Snell S. Merrill Weiss Dr. Kees Immink Stanley N. Baron William C. Miller Bernard J. Lechner Edwin E. Catmall Ray Dolby Harold E. Edgerton Vladimir K. Zworykin John G. Frayne Walt Disney Chuck Pagano James M. DeFilippis Bernard J. Lechner Stanley N. Baron William F. Schreiber Adrian Ettlinger Joseph A. Flaherty, Jr. Peter C. Goldmark W. R. G. Baker Albert Rose Charles Ginsburg Robert E. Shelby Arthur V. Loughren Otto H. Schade The Eastman Kodak Gold Medal, instituted in 1967, recognizes outstanding contributions which lead to new or unique educational programs utilizing motion pictures, high-speed and instrumentation photography or other photography sciences. Recent recipients are Andrew Laszlo James MacKay Dr. Roderick T. Ryan George Spiro Dibie Jean-Pierre Beauviala List of film topics Category:SMPTE standards Glossary of video terms SMPTE colour bars SMPTE D10 SMPTE D11 SMPTE RP-133: Medical Diagnostic Imaging Test Pattern SMPTE 421M: VC-1 video codec SMPTE 291M: Ancillary Data Packet and Space Formatting SMPTE Universal Leader Digital Picture Exchange General Exchange Format Material Exchange Format Media dispatch protocol SMPTE 2032 parts 1, 2 and 3 Video tape recorder standards defined by SMPTE Charles S. Swartz.
Understanding Digital Cinema. A Professional Handbok. Elsevier, 2005. Official website