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DV refers to a family of
codec A codec is a device or computer program that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or ...
s and tape formats used for storing
digital video Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data Digital data, in information theory and information systems, is information represented as a string of discrete symbols eac ...
, launched in 1995 by a consortium of
video camera A video camera is an optical instrument that captures videos (as opposed to a movie camera, which records images on film). Video cameras were initially developed for the television industry but have since become widely used for a variety of oth ...
manufacturers led by
Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...
and
Panasonic formerly between 1935 and 2008 and the first incarnation of between 2008 and 2022, is a major Japanese multinational conglomerate corporation, headquartered in Kadoma, Osaka. It was founded by Kōnosuke Matsushita in 1918 as a lightbulb ...
. In the late 1990s and early 2000s, DV was strongly associated with the transition from
analog Analog or analogue may refer to: Computing and electronics * Analog signal, in which information is encoded in a continuous variable ** Analog device, an apparatus that operates on analog signals *** Analog electronics, circuits which use analog ...
to digital
desktop video Desktop video refers to a phenomenon lasting from the mid-1980s to the early 1990s when the graphics capabilities of personal computers such as Commodore's Amiga, the Apple Macintosh II and specially-upgraded IBM PC compatibles had advanced to th ...
production, and also with several enduring "
prosumer A prosumer is an individual who both consumes and produces. The term is a portmanteau of the words '' producer'' and ''consumer''. Research has identified six types of prosumers: DIY prosumers, self-service prosumers, customizing prosumers, coll ...
" camera designs such as the Sony VX-1000. DV is sometimes referred to as
MiniDV DV refers to a family of codecs and tape formats used for storing digital video, launched in 1995 by a consortium of video camera manufacturers led by Sony and Panasonic. In the late 1990s and early 2000s, DV was strongly associated with the t ...
, which was the most popular tape format using a DV codec during this time. In 2003, DV was joined by a successor format called
HDV HDV is a format for recording of high-definition video on DV cassette tape. The format was originally developed by JVC and supported by Sony, Canon, and Sharp. The four companies formed the HDV Consortium in September 2003. Conceived as an af ...
, which used the same tapes but with an updated video codec; HDV cameras could typically switch between DV and HDV recording modes. In the 2010s, DV rapidly grew obsolete as cameras using
memory card A memory card is an electronic data storage device used for storing digital information, typically using flash memory. These are commonly used in digital portable electronic devices. They allow adding memory to such devices using a card in a so ...
s and
solid-state drive A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is a ...
s became the norm, recording at higher bitrates and resolutions that were impractical for mechanical tape formats. Additionally, as manufacturers switched from
interlaced Interlaced video (also known as interlaced scan) is a technique for doubling the perceived frame rate of a video display without consuming extra bandwidth. The interlaced signal contains two fields of a video frame captured consecutively. This ...
to superior progressive recording methods, they broke the
interoperability Interoperability is a characteristic of a product or system to work with other products or systems. While the term was initially defined for information technology or systems engineering services to allow for information exchange, a broader defi ...
that had previously been maintained across multiple generations of DV and HDV equipment. In the 2020s, DV codecs are still sometimes used when dealing with legacy
standard definition video Standard may refer to: Symbols * Colours, standards and guidons, kinds of military signs * Standard (emblem), a type of a large symbol or emblem used for identification Norms, conventions or requirements * Standard (metrology), an object t ...
. The original DV specification, known as ''Blue Book'', was standardized within the
IEC The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and r ...
 61834 family of standards. These standards define common features such as physical
videocassette Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal. Videotape is used in both video tape recorders (VTRs) and, more commonly, videocasset ...
s, recording modulation method, magnetization, and basic system data in part 1. Part 2 describes the specifics of video systems supporting 525-60 for
NTSC The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...
and 625-50 for
PAL Phase Alternating Line (PAL) is a colour encoding system for analogue television. It was one of three major analogue colour television standards, the others being NTSC and SECAM. In most countries it was broadcast at 625 lines, 50 fields (25 ...
. The IEC standards are available as publications sold by IEC and
ANSI The American National Standards Institute (ANSI ) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organi ...
.


DV compression

DV uses
lossy compression In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data si ...
of
video Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) sy ...
while audio is stored uncompressed. An
intraframe Intra-frame coding is a data compression technique used within a video frame, enabling smaller file sizes and lower bitrates, with little or no loss in quality. Since neighboring pixels within an image are often very similar, rather than storing ...
video compression In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compressio ...
scheme is used to compress video on a frame-by-frame basis with the discrete cosine transform (DCT). Closely following the
ITU-R The ITU Radiocommunication Sector (ITU-R) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU) and is responsible for radio communications. Its role is to manage the international radio-frequency ...
Rec. 601 ITU-R Recommendation BT.601, more commonly known by the abbreviations Rec. 601 or BT.601 (or its former name CCIR 601) is a standard originally issued in 1982 by the CCIR (an organization, which has since been renamed as the Internatio ...
standard, DV video employs
interlaced Interlaced video (also known as interlaced scan) is a technique for doubling the perceived frame rate of a video display without consuming extra bandwidth. The interlaced signal contains two fields of a video frame captured consecutively. This ...
scanning with the luminance sampling frequency of 13.5 MHz. This results in 480 scanlines per complete frame for the 60 Hz system, and 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 ratio Pixel aspect ratio (often abbreviated PAR) is a mathematical ratio that describes how the width of a pixel in a digital image compares to the height of that pixel. Most digital imaging systems display an image as a grid of tiny, square pix ...
s for ''fullscreen'' and ''widescreen'' video. Prior to the DCT compression stage,
chroma subsampling Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance. It is u ...
is applied to the source video in order to reduce the amount of data to be compressed. Baseline DV uses 4:1:1 subsampling in its 60 Hz variant and 4:2:0 subsampling in the 50 Hz variant. Low chroma resolution of DV (compared to higher-end digital video formats) is a reason this format is sometimes avoided in
chroma key Chroma key compositing, or chroma keying, is a visual-effects and post-production technique for compositing (layering) two images or video streams together based on colour hues ( chroma range). The technique has been used in many fields to ...
ing 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 Pulse-code modulation (PCM) is a method used to digitally represent sampled analog signals. It is the standard form of digital audio in computers, compact discs, digital telephony and other digital audio applications. In a PCM stream, the am ...
stereo Stereophonic sound, or more commonly stereo, is a method of sound reproduction that recreates a multi-directional, 3-dimensional audible perspective. This is usually achieved by using two independent audio channels through a configuration ...
at 48 kHz
sampling rate In signal processing, sampling is the reduction of a continuous-time signal In mathematical dynamics, discrete time and continuous time are two alternative frameworks within which variables that evolve over time are modeled. Discrete time ...
(768 kbit/s per channel, 1.5 Mbit/s stereo), or four nonlinear 12-bit PCM channels at 32 kHz sampling rate (384 kbit/s per channel, 1.5 MBit/s for four channels). In addition, the DV specification also supports 16-bit audio at 44.1 kHz (706 kbit/s per channel, 1.4 Mbit/s stereo), the same sampling rate used for CD audio. In practice, the 48 kHz stereo mode is used almost exclusively.


Digital Interface Format

The audio, video, and metadata are packaged into 80-byte Digital Interface Format (DIF) blocks which are multiplexed into a 150-block sequence. DIF blocks are the basic units of DV streams and can be stored as
computer file A computer file is a computer resource for recording data in a computer storage device, primarily identified by its file name. Just as words can be written to paper, so can data be written to a computer file. Files can be shared with and trans ...
s in raw form or wrapped in such file formats as
Audio Video Interleave Audio Video Interleave (also Audio Video Interleaved and known by its initials and filename extension AVI, usually pronounced ), is a proprietary multimedia container format and Windows standard introduced by Microsoft in November 1992 as part ...
(AVI),
QuickTime QuickTime is an extensible multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. Created in 1991, the latest Mac version, QuickTime X, is a ...
(QT) and
Material Exchange Format Material Exchange Format (MXF) is a container format for professional digital video and audio media defined by a set of SMPTE standards. A typical example of its use is for delivering advertisements to TV stations and tapeless archiving of broadc ...
(MXF). 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, and 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 that the sound may be +/- ⅓ frame out of sync with the video. However, this is the maximum drift of the audio/video synchronization; it is not compounded throughout the recording.


Variants

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 except for DVCPRO Progressive are recorded to tape within interlaced video stream. Film-like frame rates are possible by using pulldown. DVCPRO HD supports native progressive format when recorded to P2 memory cards.


DVCPRO

DVCPRO, also known as DVCPRO25, is a variation of DV developed by Panasonic and introduced in 1995 for use in
electronic news gathering Electronic news-gathering (ENG) or electronic journalism (EJ) is usage of electronic video and audio technologies by reporters to gather and present news instead of using film cameras. The term was coined during the rise of videotape tech ...
(ENG) equipment. Unlike baseline DV, DVCPRO uses ''locked audio'', meaning the audio sample clock runs in sync with the video sample clock, and 4:1:1
chroma subsampling Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance. It is u ...
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 audio cue and for timecode control. Tape is transported 80% faster compared to baseline DV, resulting in shorter recording time. Long Play mode is not available.


DVCPRO50

DVCPRO50 was introduced by Panasonic in 1997 for high-value electronic news gathering and
digital cinema Digital cinema refers to adoption of digital technology within the film industry to distribute or project motion pictures as opposed to the historical use of reels of motion picture film, such as 35 mm film. Whereas film reels have to be sh ...
, and is often 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 where
high definition video High-definition video (HD video) is video of higher resolution and quality than standard-definition. While there is no standardized meaning for ''high-definition'', generally any video image with considerably more than 480 vertical scan lines ( ...
was not required. For example, BBC used DVCPRO50 to record high-budget TV series, such as ''
Space Race The Space Race was a 20th-century competition between two Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the t ...
'' (2005) and '' Ancient Rome: The Rise and Fall of an Empire'' (2006). A similar format, D-9 (or Digital-S), offered by JVC, uses videocassettes with the same form-factor as VHS. Comparable high quality standard definition digital tape formats include Sony's Digital Betacam, launched in 1993, and MPEG IMX, launched in 2001.


DVCPRO Progressive

DVCPRO ''Progressive'' was introduced by Panasonic for news gathering, sports journalism and digital cinema. It offered 480 or 576 lines of progressive scan recording with 4:2:0 chroma subsampling and four 16-bit 48 kHz PCM audio channels. Like HDV-SD, it was meant as an intermediate format during the transition time from standard definition to high definition video. The format offered six modes for recording and playback: 16:9 progressive (50 Mbit/s), 4:3 progressive (50 Mbit/s), 16:9 interlaced (50 Mbit/s), 4:3 interlaced (50 Mbit/s), 16:9 interlaced (25 Mbit/s), 4:3 interlaced (25 Mbit/s). The format has been superseded by DVCPRO HD.


DVCPRO HD

''DVCPRO HD'', also known as ''DVCPRO100'' and ''D-12'', is a
high-definition video High-definition video (HD video) is video of higher resolution and quality than standard-definition. While there is no standardized meaning for ''high-definition'', generally any video image with considerably more than 480 vertical scan lines ...
format that can be thought of as four DV codecs that work in parallel. Video data rate depends on frame rate and can be as low as 40 Mbit/s for 24 frame/s mode and as high as 100 Mbit/s for 50/60 frame/s modes. Like DVCPRO50, DVCPRO HD employs 4:2:2 color sampling. DVCPRO HD uses smaller raster size than broadcast high definition television: 960x720 pixels for 720p, 1280x1080 for 1080/59.94i and 1440x1080 for 1080/50i. Similar horizontal downsampling (using rectangular pixels) is used in many other magnetic tape-based HD formats such as
HDCAM HDCAM is a high-definition video digital recording videocassette version of Digital Betacam introduced in 1997 that uses an 8-bit discrete cosine transform (DCT) compressed 3:1:1 recording, in 1080i-compatible down-sampled resolution of 14 ...
. To maintain compatibility with HD-SDI, DVCPRO100 equipment upsamples video during playback. Variable framerates (from 4 to 60 frame/s) are available on ''VariCam'' camcorders. DVCPRO HD equipment offers
backward compatibility Backward compatibility (sometimes known as backwards compatibility) is a property of an operating system, product, or technology that allows for interoperability with an older legacy system, or with input designed for such a system, especiall ...
with older DV/DVCPRO formats. When recorded to tape in standard-play mode, DVCPRO HD uses the same 18 μm track pitch as other DVCPRO flavors. A long play variant, DVCPRO HD-LP, doubles the recording density by using 9 μm track pitch. DVCPRO HD is codified as SMPTE 370M; the DVCPRO HD tape format is SMPTE 371M, and the MXF Op-Atom format used for DVCPRO HD on P2 cards is SMPTE 390M. While technically DVCPRO HD is a direct descendant of DV, it is used almost exclusively by professionals. Tape-based DVCPRO HD cameras exist only in shoulder mount variant. A similar format, Digital-S (D-9 HD), was offered by JVC and used videocassettes with the same form-factor as VHS. The main competitor to DVCPRO HD was
HDCAM HDCAM is a high-definition video digital recording videocassette version of Digital Betacam introduced in 1997 that uses an 8-bit discrete cosine transform (DCT) compressed 3:1:1 recording, in 1080i-compatible down-sampled resolution of 14 ...
, offered by Sony. It uses a similar compression scheme but at higher bitrate.


DVCAM

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, which is 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.


Digital8

Digital8 is a combination of the tape transport originally designed for analog
Video8 The 8mm video format refers informally to three related videocassette formats. These are the original Video8 (analog recording) format and its improved successor Hi8 (analog video and analog audio but with provision for digital audio), as well as ...
and Hi8 formats with the DV
codec A codec is a device or computer program that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or ...
. Digital8 equipment records in DV format only, but usually can playback Video8 and Hi8 tapes as well.


Comparison of DV implementations


Progressive recording

Tape-based DV variants, except for DVCPRO Progressive, do not support native progressive recording, therefore progressively acquired video is recorded within interlaced video stream using pulldown. The same technique is used in television industry to broadcast movies. Progressive-scan DV camcorders for 60 Hz market record 24-frame/s video using 2-3 pulldown and 30-frame/s video using 2-2 pulldown. Progressive-scan DV camcorders for 50 Hz market record 25-frame/s video using 2-2 pulldown. Progressive video can be recorded with interlaced delivery in mind, in which case high-frequency information between fields is blended to suppress
interline twitter Interlaced video (also known as interlaced scan) is a technique for doubling the perceived frame rate of a video display without consuming extra bandwidth. The interlaced signal contains two fields of a video frame captured consecutively. This ...
. If the goal is progressive-scan distribution like Web videos, progressive-scan
DVD-video DVD-Video is a consumer video format used to store digital video on DVD discs. DVD-Video was the dominant consumer home video format in Asia, North America, Europe, and Australia in the 2000s until it was supplanted by the high-definition Blu- ...
or
film-out Film-out is the process in the computer graphics, video production and filmmaking disciplines of transferring images or animation from videotape or digital files to a traditional film print. ''Film-out'' is a broad term that encompasses the conve ...
, then no filtering is applied. Video recorded with 2-2 pulldown and no vertical filtering is conceptually identical to
progressive segmented frame Progressive segmented Frame (PsF, sF, SF) is a scheme designed to acquire, store, modify, and distribute progressive scan video using interlaced equipment. With PsF, a progressive frame is divided into two ''segments'', with the odd lines in one s ...
. Consumer-grade DV camcorders capable of progressive recording usually offer only 2-2 pulldown scheme because of its simplicity. Such a video can be edited as either interlaced or progressive and does not require additional processing aside of treating every pair of fields as one complete frame. Canon and Panasonic call this format ''Frame Mode'', while Sony calls it ''Progressive Scan recording''. 24 frame/s recording is available only on professional DV camcorders and requires ''pulldown removal'' if editing at native frame rate is required. DVCPRO HD supports native progressive recording at 50 or 60 frame/s in 720p mode. To record video acquired at 24, 25 or 30 frame/s frame repeating is used. Frame repeating is similar to field repeating used in interlaced video, and is also called pulldown sometimes.


Recording media


Magnetic tape

DV was originally designed for recording onto
magnetic tape Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnet ...
. Tape is enclosed into
videocassette Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal. Videotape is used in both video tape recorders (VTRs) and, more commonly, videocasset ...
of four different sizes: small, medium, large and extra-large. All DV cassettes use ¼ inch (6.35 mm) wide tape. Small cassettes (66 x 48 x 12.2 mm), also known as ''S-size'' or ''DVC'' or ''MiniDV'' cassettes, had been intended for amateur use, but have become accepted in professional productions as well. MiniDV cassettes are used for recording baseline DV, DVCAM, and
HDV HDV is a format for recording of high-definition video on DV cassette tape. The format was originally developed by JVC and supported by Sony, Canon, and Sharp. The four companies formed the HDV Consortium in September 2003. Conceived as an af ...
. These cassettes come in lengths up to about 14~20.8 GB for 63 or 90min minutes of DV or HDV video. When recording in DVCAM, these cassettes hold up to 41 minutes of video. There are some 83-minute versions but these use thinner tape than the 63-minute ones, and Panasonic advised against playing these cassettes in DVCPRO decks. Medium or ''M-size'' cassettes (97.5 × 64.5 × 14.6 mm), which are about the size of eight-millimeter cassettes, are used in professional Panasonic equipment and are often called ''DVCPRO tapes''. Panasonic video recorders that accept medium cassette can play back from and record to medium cassette in different flavors of DVCPRO format; they will also play small cassettes containing DV or DVCAM recording via an adapter. These cassettes come in lengths up to 66 minutes for DVCPRO, 33 minutes for DVCPRO50 and DVCPRO HD-LP, and 16 minutes for the original DVCPRO HD. Large or ''L-size'' cassettes (125.1 x 78 x 14.6 mm) are close in dimensions to
Betacam Betacam is a family of half-inch professional videocassette products developed by Sony in 1982. In colloquial use, "Betacam" singly is often used to refer to a Betacam camcorder, a Betacam tape, a Betacam video recorder or the format itself. Al ...
cassettes and are accepted by most standalone DV tape recorders and are used in many shoulder-mount camcorders. The L-size cassette can be used in both Sony and Panasonic equipment; nevertheless, they are often called ''DVCAM tapes''. Older Sony decks would not play large cassettes with DVCPRO recordings, but newer models can play these and M-size DVCPRO cassettes. These cassettes come in lengths up to 276 minutes of DV or HDV video (or 184 minutes for DVCAM). Unlike the VHS and Digital8 formats that use thinner tape for their longest-length variants, the 276-minute DV cassette employs the same tape as its shorter-length variants. On the DVCPRO side, these cassettes have nearly double the tape capacity of their M-size counterparts, with duration up to 126 minutes for DVCPRO, 64 minutes for DVCPRO50 and DVCPRO HD-LP, and 32 minutes for the original DVCPRO HD. A thin-tape 184/92/46-minute version was also released. Extra-large cassettes or ''XL-size'' (172 x 102 x 14.6 mm) have been designed for use in Panasonic equipment and are sometimes called DVCPRO XL. These cassettes are not widespread, only a few models of Panasonic tape recorders can accept them. Each XL-size cassette holds nearly double the amount of tape as the full-length L-size cassettes with a capacity of 252 minutes of DVCPRO video or 126 minutes of DVCPRO50 or DVCPRO HD-LP video. Technically, any DV cassette can record any variant of DV video. Nevertheless, manufacturers often label cassettes with DV, DVCAM, DVCPRO, DVCPRO50 or DVCPRO HD and indicate recording time with regards to the label posted. Cassettes labeled as DV indicate recording time of baseline DV; another number can indicate recording time of Long Play DV. Cassettes labeled as DVCPRO have a yellow tape door and indicate recording time when DVCPRO25 is used; with DVCPRO50 the recording time is half, with DVCPRO HD it is a quarter. Cassettes labeled as DVCPRO50 have a blue tape door and indicate recording time when DVCPRO50 is used. Cassettes labeled as DVCPRO HD have a red tape door and indicate recording time when DVCPRO HD-LP format is used; a second number may be used for DVCPRO HD recording, which will be half as long. Panasonic stipulated use of a particular magnetic-tape formulation—
metal particle Audio compact cassettes use magnetic tape of three major types which differ in fundamental magnetic properties, the level of bias applied during recording, and the optimal time constant of replay equalization. Specifications of each type were s ...
(MP)—as an inherent part of its DVCPRO family of formats. Regular DV tape uses Metal Evaporate (ME) formulation (which, as the name suggests, uses
physical vapor deposition Physical vapor deposition (PVD), sometimes called physical vapor transport (PVT), describes a variety of vacuum deposition methods which can be used to produce thin films and coatings on substrates including metals, ceramics, glass, and polym ...
to deposit metal onto the tape), which was pioneered for use in Hi8 camcorders. Early Hi8 ME tape was plagued with excessive dropouts, which forced many shooters to switch to more expensive MP tape. After the technology improved, the dropout rate was greatly reduced, nevertheless Panasonic deemed ME formulation not robust enough for professional use. Tape-based professional Panasonic DVCPRO camcorders and decks only record onto DVCPRO-branded cassettes, effectively preventing use of ME tape.


File-based media

With proliferation of
tapeless camcorder A camcorder is a self-contained portable electronic device with video and recording as its primary function. It is typically equipped with an articulating screen mounted on the left side, a belt to facilitate holding on the right side, hot-swa ...
video recording, DV video can be recorded on
optical disc In computing and optical disc recording technologies, an optical disc (OD) is a flat, usually circular disc that encodes binary data ( bits) in the form of pits and lands on a special material, often aluminum, on one of its flat surface ...
s, solid state
flash memory Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both use ...
cards and
hard disk drives A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magn ...
and used as
computer file A computer file is a computer resource for recording data in a computer storage device, primarily identified by its file name. Just as words can be written to paper, so can data be written to a computer file. Files can be shared with and trans ...
s. In particular: * Sony
XDCAM XDCAM is a series of products for digital recording using random access solid-state memory media, introduced by Sony in 2003. Four different product lines the XDCAM SD, XDCAM HD, XDCAM EX and XDCAM HD422 differ in types of en ...
family of cameras can record DV onto either
Professional Disc Professional Disc (PFD) is a digital recording optical disc format introduced by Sony in 2003 primarily for XDCAM, its tapeless camcorder system. It was one of the first optical formats to utilize a blue laser, which allowed for a higher densi ...
or SxS memory cards. * Panasonic DVCPRO HD and AVC-Intra camcorders can record DV (as well as DVCPRO) onto P2 cards. * Some Panasonic
AVCHD AVCHD (Advanced Video Coding High Definition) is a file-based format for the digital recording and playback of high-definition video. It is H.264 and Dolby AC-3 packaged into the MPEG transport stream, with a set of constraints designed around th ...
camcorders (AG-HMC80, AG-AC130, AG-AC160) record DV video onto
Secure Digital Secure Digital, officially abbreviated as SD, is a proprietary non-volatile flash memory card format developed by the SD Association (SDA) for use in portable devices. The standard was introduced in August 1999 by joint efforts between SanDis ...
memory cards. * JVC GY-HM750 can be set to standard definition mode and in this case will record '.AVI or .MOV SD legacy format' video onto SDHC cards. ''For clarity - and contrary to what has previously been written'', the camera ''does not'' natively support SxS memory cards, has no slots for them and requires an optional add-on recorder (or 'adapter' as JVC call it) to achieve this - basically this camera is an 'XDCAM EX' High definition unit and the add-on SxS recorder was only made available to achieve better compatibility in facilities which were Sony based. * Most DV and
HDV HDV is a format for recording of high-definition video on DV cassette tape. The format was originally developed by JVC and supported by Sony, Canon, and Sharp. The four companies formed the HDV Consortium in September 2003. Conceived as an af ...
camcorders can feed live DV stream over
IEEE 1394 interface IEEE 1394 is an interface standard for a serial bus for high-speed communications and isochronous real-time data transfer. It was developed in the late 1980s and early 1990s by Apple in cooperation with a number of companies, primarily Sony an ...
to an external file-based recorder. Video is stored either as native DIF bitstream or wrapped into an audio/video
container A container is any receptacle or enclosure for holding a product used in storage, packaging, and transportation, including shipping. Things kept inside of a container are protected on several sides by being inside of its structure. The term ...
such as
AVI Avi is a given name, usually masculine, often a diminutive of Avram, Avraham, etc. It is sometimes feminine and a diminutive of the Hebrew spelling of Abigail. People with the given name include: * Avi (born 1937), Newbery award-winning Americ ...
,
QuickTime QuickTime is an extensible multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. Created in 1991, the latest Mac version, QuickTime X, is a ...
or MXF. * ''DV-DIF'' is the raw form of DV video. The files usually have extensions *.dv or *.dif. * '' DV-AVI'' is
Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washi ...
's implementation of DV video file, which is wrapped into an AVI container. Two variants of wrapping are available: with Type 1 the multiplexed audio and video is saved into the video section of a single AVI file, with Type 2 video and audio are saved as separate streams in an AVI file (one video stream and one to four audio streams). This container is used primarily on Windows-based computers, though Sony offers two tapeless recorders, the HDD-based HVR-DR60 and the CompactFlash-based HVR-MRC1K, for use with DV/HDV camcorders that can record in DV-AVI format either making a file-based copy of the tape or bypassing tape recording altogether. Panasonic AVCHD camcorders use Type 2 DV-AVI for recording DV video onto Secure Digital memory card. * ''
QuickTime QuickTime is an extensible multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. Created in 1991, the latest Mac version, QuickTime X, is a ...
-DV'' is DV video wrapped into QuickTime container. This container is used primarily on Apple computers. * ''MXF-DV'' wraps DV video into MXF container, which is presently used on P2-based camcorders (Panasonic) and on XDCAM/XDCAM EX camcorders (Sony).


Connectivity

Nearly all DV camcorders and decks have
IEEE 1394 IEEE 1394 is an interface standard for a serial bus for high-speed communications and isochronous real-time data transfer. It was developed in the late 1980s and early 1990s by Apple in cooperation with a number of companies, primarily Sony an ...
(FireWire, i.LINK) ports for digital video transfer. This is usually a two-way port, so that DV video data can be ''output'' to a computer (DV-out), or ''input'' from either a computer or another camcorder (DV-in). The DV-in capability makes it possible to copy edited DV video from a computer back onto tape, or make a lossless copy between two mutually connected DV camcorders. However, models made for sale in the
European Union The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are located primarily in Europe, Europe. The union has a total area of ...
usually had the DV-in capability disabled in the firmware by the manufacturer because the camcorder would be classified by the EU as a video recorder and would therefore attract higher duty; a model which only had DV-out could be sold at a lower price in the EU. When video is captured onto a computer it is stored in a container file, which can be either raw DV stream, AVI, WMV or QuickTime. Whichever container is used, the video itself is not re-encoded and represents a complete digital copy of what has been recorded onto tape. If needed, the video can be recorded back to tape to create a full and lossless copy of the original footage. Some camcorders also feature a USB 2.0 port for computer connection. This port is usually used for transferring still images, but not for video transfer. Camcorders that offer video transfer over USB usually do not deliver full DV quality - usually it is 320x240 video, except for the Sony DCR-PC1000 camcorder and some Panasonic camcorders that provide transfer of a full-quality DV stream via USB by using the UVC protocol. Full-quality DV can also be captured via USB or Thunderbolt by using separate hardware that receives DV data from the camcorder over a FireWire cable and forwards it without any transcoding to the computer via a USB cable or a Firewire to Thunderbolt adapter - this can be particularly useful for capturing on modern laptop computers which usually do not have a FireWire port or expansion slot but always have USB or Thunderbolt ports. High end cameras and VTRs may have additional professional outputs such as SDI, SDTI or analog
component video Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Compo ...
. All DV variants have a
time code A timecode (alternatively, time code) is a sequence of numeric codes generated at regular intervals by a timing synchronization system. Timecode is used in video production, show control and other applications which require temporal coordinatio ...
, but some older or consumer computer applications fail to take advantage of it.


Usage

The high quality of DV images, especially when compared to Video8 and Hi8 which were vulnerable to an unacceptable number of video dropouts and "hits", prompted the acceptance by mainstream broadcasters of material shot on DV. The low costs of DV equipment and their ease of use put such cameras in the hands of a new breed of videojournalists. Programs such as TLC's Trauma: Life in the E.R. and ABC News's Hopkins: 24/7 were shot on DV. DVCPRO HD was the preferred high definition standard of BBC Factual.


Films

Notable films to use the DV format include: * ''
Love & Pop is a 1998 Japanese experimental coming-of-age film directed and co-written by Hideaki Anno, based on the novel ''Topaz II'' by Ryū Murakami''.'' It was Anno's first live action feature-length film. The film was shot almost entirely on hand-held ...
'' (
Hideaki Anno is a Japanese animator, filmmaker and actor. He is best known for creating the anime series ''Neon Genesis Evangelion'' (1995)''.'' His style is defined by his postmodernist approach and the extensive portrayal of characters' thoughts and emotio ...
—1998) * '' The Cruise'' (
Bennett Miller Bennett Miller (born December 30, 1966) is an American film director, known for directing the acclaimed films '' Capote'' (2005), ''Moneyball'' (2011), and ''Foxcatcher'' (2014). He has been nominated twice for the Academy Award for Best Director ...
—1998) * ''
The Gleaners and I ''The Gleaners and I'' (french: Les glaneurs et la glaneuse, lit. "The gleaners and the female gleaner") is a 2000 French documentary film by Agnès Varda that features various kinds of gleaning. It was entered into competition at the 2000 Cannes F ...
'' (
Agnès Varda Agnès Varda (; born Arlette Varda; 30 May 1928 – 29 March 2019) was a Belgian-born French film director, screenwriter, photographer, and artist. Her pioneering work was central to the development of the widely influential French New Wave film ...
—2000) * '' Chuck and Buck'' (
Miguel Arteta Miguel Arteta (born 1965) is a Puerto Rican director of film and television, known for his independent film ''Chuck & Buck'' (2000), for which he received the Independent Spirit John Cassavetes Award, and for the films '' The Good Girl'' (2002 ...
—2000) *''The Gleaners and I: Two Years Later'' (
Agnès Varda Agnès Varda (; born Arlette Varda; 30 May 1928 – 29 March 2019) was a Belgian-born French film director, screenwriter, photographer, and artist. Her pioneering work was central to the development of the widely influential French New Wave film ...
—2002) *''
28 Days Later ''28 Days Later'' is a 2002 British post-apocalyptic horror film directed by Danny Boyle and written by Alex Garland. It stars Cillian Murphy as a bicycle courier who awakens from a coma to discover the accidental release of a highly contagiou ...
'' (
Danny Boyle Daniel Francis Boyle (born 20 October 1956) is an English director and producer. He is known for his work on films including '' Shallow Grave'', '' Trainspotting'' and its sequel '' T2 Trainspotting'', '' The Beach'', ''28 Days Later'', '' S ...
—2002) * ''
Inland Empire The Inland Empire (IE) is a metropolitan area and region inland of and adjacent to coastal Southern California, centering around the cities of San Bernardino and Riverside, and bordering Los Angeles County to the west. It includes the citie ...
'' (
David Lynch David Keith Lynch (born January 20, 1946) is an American filmmaker, visual artist and actor. A recipient of an Academy Honorary Award in 2019, Lynch has received three Academy Award nominations for Best Director, and the César Award for Be ...
—2006) * ''
Iraq in Fragments ''Iraq in Fragments'' is a documentary film directed by James Longley. Longley shot the film in Digital Video on a Panasonic DVX100 miniDV camcorder. The film premiered at the 2006 Sundance Film Festival where it won three awards: "Directing Award ...
'' ( James Longley—2006) * ''
Rec REC or Rec is a shortening of Recording, the process of capturing data onto a storage medium. REC may also refer to: Educational institutes * Regional Engineering College, colleges of engineering and technology education in India * Rajalakshmi ...
'' ( Jaume Balagueró &
Paco Plaza Francisco Plaza Trinidad (born 8 February 1973), simply known as Paco Plaza, is a Spanish filmmaker known for his works in the horror genre. He is the co-creator of the ''REC'' zombie film franchise. Career Francisco Plaza Trinidad was born on ...
—2007) * ''My First Kiss and the People Involved'' (Luigi Campi & Giacomo Belletti—2016)


Application software support

Most DV players, editors and encoders only support the basic DV format, but not its professional versions. The exception to this being that most (not all) consumer Sony miniDV equipment will play mini-DVCAM tapes. DV Audio/Video data can be stored as raw DV data stream file (data is written to a file as the data is received over FireWire, file extensions are .dv and .dif) or the DV data can be packed into container files (ex: Microsoft
AVI Avi is a given name, usually masculine, often a diminutive of Avram, Avraham, etc. It is sometimes feminine and a diminutive of the Hebrew spelling of Abigail. People with the given name include: * Avi (born 1937), Newbery award-winning Americ ...
, Apple MOV). The DV meta-information is preserved in both file types being Sub-timecode and Start/Stop date times witch can be muxed to Quicktime SMPTE standard timecode. Most
Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for se ...
video software only supports DV in AVI containers, as they use
Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washi ...
's avifile.dll, which only supports reading avi files.
Mac OS X macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and lap ...
video software support both AVI and MOV containers.


Mixing tapes from different manufacturers

There was considerable controversy solely based on hearsay over whether or not using tapes from different manufacturers could lead to dropouts. Initially this was suggested around the conception of mostly MiniDV tapes in the mid to late 90s as the only two manufacturers of MiniDV tapes (Sony, who produce their tapes solely under the Sony brand; and Panasonic, who produce their own tapes under their Panasonic brand and outsources for TDK, Canon, etc.) used two different lubrication types for their cameras - Sony uses a 'wet' lubricant ('ME' or 'Metal Evaporated'), while Panasonic uses a 'dry' lubricant ('MP' or 'Metal Particle'). The standard practice for casual and professional camera operators alike is not to mix brands of tapes. (as the different lubrication formulations can cause or encourage tape wear if not cleaned by a cleaning cassette) No significant problems have occurred for the last few years - meaning that switching tapes is acceptable, though sticking to one brand (and cleaning the heads with a cleaning cassette before doing so) is highly recommended. A research undertaken by Sony claimed that there was no hard evidence of the above statement. The only evidence claimed was that using ME tapes in equipment designed for MP tapes can cause tape damage and hence dropouts.The Truth About Tape Lubricant
/ref> Sony has done a significant amount of internal testing to simulate head clogs as a result of mixing tape lubricants, and has been unable to recreate the problem. Sony recommends using cleaning cassettes once every 50 hours of recording or playback. For those who are still skeptical, Sony recommends cleaning video heads with a cleaning cassette before trying another brand of tape.


References


External links



{{DEFAULTSORT:Dv Video storage History of television Television terminology