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Wikipedia

DV

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 transition from analog to digital desktop video production, and also with several enduring "prosumer" camera designs such as the Sony VX-1000.[1] DV is sometimes referred to as MiniDV, which was the most popular tape format using a DV codec during this time.

DV
DV cassettes: DVCAM-L, DVCPRO-M, MiniDV
Media typeMagnetic cassette tape
EncodingDV
Read mechanismHelical scan
Write mechanismHelical scan
Developed bySony
Panasonic
UsageCamcorders, Home movies
Released1995; 28 years ago (1995)

In 2003, DV was joined by a successor format called HDV, which used the same tapes but with an updated video codec; HDV cameras could typically switch between DV and HDV recording modes.[2] In the 2010s, DV rapidly grew obsolete as cameras using memory cards and solid-state drives became the norm, recording at higher bitrates and resolutions that were impractical for mechanical tape formats. Additionally, as manufacturers switched from interlaced to superior progressive recording methods, they broke the interoperability 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.

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, magnetization, and basic system data in part 1. Part 2 describes the specifics of video systems supporting 525-60 for NTSC and 625-50 for PAL.[3] The IEC standards are available as publications sold by IEC and ANSI.

DV compression

DV uses lossy compression of video while audio is stored uncompressed.[4] An intraframe video compression scheme is used to compress video on a frame-by-frame basis with the discrete cosine transform (DCT).

Closely following the ITU-R Rec. 601 standard, DV video employs interlaced 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 ratios for fullscreen and widescreen video.[5][6]

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 4:1:1 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 keying applications, though advances in chroma keying techniques and software have made producing quality keys from DV material possible.[7][8]

Audio can be stored in either of two forms: 16-bit Linear PCM stereo at 48 kHz sampling rate (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.[9] 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 files in raw form or wrapped in such file formats as Audio Video Interleave (AVI), QuickTime (QT) and Material Exchange Format (MXF).[10][11] 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.[5]

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 compatibility mark
 
Tracks on DVCPRO tape (in Russian)
 
Panasonic AJ-D455 VCR for professional video use with IEEE 1394 port and DV capability

DVCPRO, also known as DVCPRO25 and D-7, is a variation of DV developed by Panasonic and introduced in 1995, originally intended for use in electronic news gathering (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 for both 50 Hz and 60 Hz variants to decrease generation losses.[12] 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,[13] 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 compatibility mark
 
Panasonic AJ-D950 DVCPRO50 VCR
 
Panasonic AJ-D95DC VCR

DVCPRO50 was introduced by Panasonic in 1997 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 was not required. For example, BBC used DVCPRO50 to record high-budget TV series, such as Space Race (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 2000.

DVCPRO Progressive

 
DVCPRO Progressive mark

DVCPRO Progressive was introduced by Panasonic alongside DVCPRO50. 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.[14][15]

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).[16]

The format was superseded by DVCPRO HD.

DVCPRO HD

 
DVCPRO HD compatibility mark
 
Panasonic AJ-HDX900 camcorder

DVCPRO HD, also known as DVCPRO100 and D-12, is a high-definition video 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. It was introduced in 2000.[17]

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. 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 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, offered by Sony. It uses a similar compression scheme but at higher bitrate.

DVCAM

 
DVCAM compatibility mark

In 1996, Sony responded with its own professional version of DV called DVCAM.[18]

Like DVCPRO, DVCAM uses locked audio, which prevents audio synchronization drift that may happen on DV if several generations of copies are made.[19]

When recorded to tape, DVCAM uses 15 μm track pitch, which is 50% wider compared to baseline.[13] 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 and Hi8 formats with the DV codec. Digital8 equipment records in DV format only, but usually can playback Video8 and Hi8 tapes as well.

Comparison of DV implementations

Feature[20][21][22] DV DVCAM DVCPRO DVCPRO50 DIGITAL‑S Digital8
Suppliers Sony, Panasonic, JVC, Canon, Sharp and others. Sony, Ikegami. Panasonic; also Philips, Ikegami, Hitachi. Panasonic JVC Sony, Hitachi.
Bit rate (Mbps) 25 50 25
Bit depth luma: 8, chroma: 8
525/60 subsampling 4:1:1 4:2:2 4:1:1
625/50 subsampling 4:2:0 4:1:1 4:2:2 4:2:0
525/60 frame size 720 × 480 720 × 487.5 720 × 480
625/50 frame size 720 × 576 720 × 583.5 720 × 576
Audio frequency (KHz) 32, 44.1, 48 32, 48 (44.1 nonpro mode) 48 32, 44.1, 48
Audio mode Locked/unlocked Locked Locked/unlocked
Track pitch (μm) 10 (SP), 6.7 (LP) 15 18 (plays 10 and 15) 20 16.34
Tape speed (mm/s) 18.8 29.193 33.8 525: 67.640, 625: 67.708 57.737 28.666
Tracks per frame 525: 10, 625: 12 ? ? 25

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. If the goal is progressive-scan distribution like Web videos, progressive-scan DVD-video or film-out, then no filtering is applied. Video recorded with 2-2 pulldown and no vertical filtering is conceptually identical to progressive segmented frame.

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

 
MiniDV mark

DV was originally designed for recording onto magnetic tape. Tape is enclosed into videocassette of four different sizes: small, medium, large and extra-large. All DV cassettes use 14 inch (6.4 mm) wide tape. DV on magnetic tape uses helical scan, which wraps the tape around a tilted, rotating head drum with video heads mounted to it. As the drum rotates, the heads read the tape diagonally. DV uses a 21.7 mm diameter head drum at 9000 rpm. The diagonal video tracks read by the heads are 10 microns wide.[23][13]

Small cassettes (66 x 48 x 12.2 mm),[24] 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. These cassettes come in lengths up to about 14~20.8GB for 63 or 90min minutes of DV or HDV video.[25] 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),[24] 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.

 
DVCAM cassettes in both miniDV and large size

Large or L-size cassettes (125.1 x 78 x 14.6 mm)[24] are close in dimensions to Betacam 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.

 
Various DVCPRO cassettes in different sizes

Extra-large cassettes or XL-size (172 x 102 x 14.6 mm)[24] 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 (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 to deposit metal onto the tape[26]), 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.

 
A disassembled MiniDV cassette
 
Mini-DV tape mechanism inside an early 2000s Panasonic Palmcorder. Quarter for scale.
Cassette Formats DV DVCPRO DVCAM
Small S-size / "MiniDV"   Only made MiniDV adapters  
Medium M-size -   -
Large L-size      
Extra Large XL-size -   -

File-based media

With proliferation of tapeless camcorder video recording, DV video can be recorded on optical discs, solid state flash memory cards and hard disk drives and used as computer files. In particular:

  • Sony XDCAM family of cameras can record DV onto either Professional Disc or SxS memory cards.
  • Panasonic DVCPRO HD and AVC-Intra camcorders can record DV (as well as DVCPRO) onto P2 cards.
  • Some Panasonic AVCHD camcorders (AG-HMC80, AG-AC130, AG-AC160) record DV video onto Secure Digital 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 camcorders can feed live DV stream over IEEE 1394 interface to an external file-based recorder.

Video is stored either as native DIF bitstream or wrapped into an audio/video container such as AVI, QuickTime or MXF.

  • DV-DIF is the raw form of DV video. The files usually have extensions *.dv or *.dif.
  • DV-AVI is Microsoft'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[27] and the CompactFlash-based HVR-MRC1K,[28] 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.[29]
  • QuickTime-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 (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 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;[30] 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[31] or a Firewire to Thunderbolt adapter[32] - 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. All DV variants have a time code, 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.[citation needed]

DVCPRO HD was the preferred high definition standard of BBC Factual.[33]

Films

Notable films to use the DV format include:

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, Apple MOV). The DV meta-information is preserved in both file types being Sub-timecode and Start/Stop date times which can be muxed to Quicktime SMPTE standard timecode.

Most Windows video software only supports DV in AVI containers, as they use Microsoft's avifile.dll, which only supports reading avi files. Mac OS X 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.[35][36] 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.[citation needed]

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.[37][unreliable source?] 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.[dubious ] 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.

See also

References

  1. ^ "The Consumer Electronics Hall of Fame: Sony DCR-VX1000 - IEEE Spectrum". IEEE Spectrum: Technology, Engineering, and Science News. 3 January 2019. Retrieved 27 June 2021.
  2. ^ "HV10 - Canon Camera Museum". global.canon. Retrieved 21 July 2016.
  3. ^ "Recording – Helical-scan digital videocassette recording system using 6,35 mm magnetic tape for consumer use" (PDF).
  4. ^ "DV Q&A Our Expert Answers Your Questions". Videomaker magazine. Videomaker, Inc. October 1999.
  5. ^ a b (PDF). Archived from the original (PDF) on 28 September 2011.
  6. ^ "Digital Video and Field Order". dvmp.co.uk.
  7. ^ . 24 March 2006. Archived from the original on 24 March 2006.
  8. ^ "The DV, DVCAM, & DVCPRO Formats – tech details, FAQ, and links". adamwilt.com.
  9. ^ Puhovski, Nenad (April 2000). "DV – A SUCCESS STORY". www.stanford.edu. Retrieved 26 August 2013.
  10. ^ "DV-DIF (Digital Video Digital Interface Format)". digitalpreservation.gov. 26 December 2011.
  11. ^ . debian.org. Archived from the original on 7 January 2010. Retrieved 9 November 2009.
  12. ^ "The DV, DVCAM, & DVCPRO Formats – tech details, FAQ, and links". adamwilt.com.
  13. ^ a b c Tozer, E. P. J. (12 November 2012). Broadcast Engineer's Reference Book. CRC Press. ISBN 9781136024184 – via Google Books.
  14. ^ "Caporale Studios Shoots Feature Films with Panasonic 480p DVCPRO50 Camcorder". dvformat.com.
  15. ^ . Archived from the original on 21 November 2010.
  16. ^ (PDF). Archived from the original (PDF) on 20 July 2011. Retrieved 10 November 2009.
  17. ^ Pizzi, Skip; Jones, Graham (24 April 2014). A Broadcast Engineering Tutorial for Non-Engineers. CRC Press. ISBN 9781317906834 – via Google Books.
  18. ^ https://cvp.com/pdf/sony_dvcam_family.pdf[bare URL PDF]
  19. ^ . Archived from the original on 11 June 2011.
  20. ^ "Sony announces Digital8 video format". Retrieved 12 September 2022.
  21. ^ "The DV formats tabulated". Retrieved 12 September 2022.
  22. ^ "DV Technology Comparison". Retrieved 12 September 2022.
  23. ^ Trundle, Eugene (18 June 2001). Newnes Guide to Television and Video Technology. Newnes. ISBN 9780750648103 – via Google Books.
  24. ^ a b c d "Media Recognition: DV part 1". 26 March 2012.
  25. ^ "Appendix B: Data Rates and Storage Needs for Various Digital Formats". The Filmmaker's Handbook: A Comprehensive Guide for the Digital Age (PDF). {{cite book}}: |website= ignored (help)
  26. ^ S.B. Luitjens, S.E. Stupp, J.C. Lodder, Metal evaporated tape: state of the art and prospects, Journal of Magnetism and Magnetic Materials, Volume 155, Issues 1–3, 1996, Pages 261-265, ISSN 0304-8853, https://doi.org/10.1016/0304-8853(95)00727-X
  27. ^ "HVR-DR60 HDV hard disk recorder".
  28. ^ "HVR-MRC1K Memory Recording Unit".
  29. ^ "Panasonic AG-HMC80 operating instructions" (PDF).
  30. ^ "Why is the DV input disabled on most digital camcorders sold in Europe?". 5 April 2001. Retrieved 1 February 2020.
  31. ^ "How to Capture DV video via USB". dvmp.co.uk.
  32. ^ "How to Capture DV video via Thunderbolt on Windows". dvmp.co.uk.
  33. ^ (PDF). 25 May 2011. Archived from the original (PDF) on 25 May 2011.
  34. ^ Bankston, Douglas (1 July 2003). "Anthony Dod Mantle, DFF injects the apocalyptic 28 Days Later with a strain of digital video". TheASC.com. Retrieved 1 May 2007.
  35. ^ "DV Tape FAQ". zenera.com.
  36. ^ Adam J. Wilt. "Adam Wilt's Video Tidbits". adamwilt.com.
  37. ^ The Truth About Tape Lubricant

External links

  • Adam Wilt's DV page with in-depth technical information

other, uses, disambiguation, refers, family, codecs, tape, formats, used, storing, digital, video, launched, 1995, consortium, video, camera, manufacturers, sony, panasonic, late, 1990s, early, 2000s, strongly, associated, with, transition, from, analog, digit. For other uses see DV disambiguation 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 transition from analog to digital desktop video production and also with several enduring prosumer camera designs such as the Sony VX 1000 1 DV is sometimes referred to as MiniDV which was the most popular tape format using a DV codec during this time DVDV cassettes DVCAM L DVCPRO M MiniDVMedia typeMagnetic cassette tapeEncodingDVRead mechanismHelical scanWrite mechanismHelical scanDeveloped bySonyPanasonicUsageCamcorders Home moviesReleased1995 28 years ago 1995 In 2003 DV was joined by a successor format called HDV which used the same tapes but with an updated video codec HDV cameras could typically switch between DV and HDV recording modes 2 In the 2010s DV rapidly grew obsolete as cameras using memory cards and solid state drives became the norm recording at higher bitrates and resolutions that were impractical for mechanical tape formats Additionally as manufacturers switched from interlaced to superior progressive recording methods they broke the interoperability 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 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 magnetization and basic system data in part 1 Part 2 describes the specifics of video systems supporting 525 60 for NTSC and 625 50 for PAL 3 The IEC standards are available as publications sold by IEC and ANSI Contents 1 DV compression 2 Digital Interface Format 3 Variants 3 1 DVCPRO 3 1 1 DVCPRO50 3 1 2 DVCPRO Progressive 3 1 3 DVCPRO HD 3 2 DVCAM 3 3 Digital8 3 4 Comparison of DV implementations 4 Progressive recording 5 Recording media 5 1 Magnetic tape 5 2 File based media 6 Connectivity 7 Usage 8 Films 9 Application software support 10 Mixing tapes from different manufacturers 11 See also 12 References 13 External linksDV compression EditDV uses lossy compression of video while audio is stored uncompressed 4 An intraframe video compression scheme is used to compress video on a frame by frame basis with the discrete cosine transform DCT Closely following the ITU R Rec 601 standard DV video employs interlaced 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 ratios for fullscreen and widescreen video 5 6 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 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 keying applications though advances in chroma keying techniques and software have made producing quality keys from DV material possible 7 8 Audio can be stored in either of two forms 16 bit Linear PCM stereo at 48 kHz sampling rate 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 9 In practice the 48 kHz stereo mode is used almost exclusively Digital Interface Format EditThe 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 files in raw form or wrapped in such file formats as Audio Video Interleave AVI QuickTime QT and Material Exchange Format MXF 10 11 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 5 Baseline DV employs unlocked audio This means that the sound may be 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 EditSony and Panasonic created their proprietary versions of DV aimed toward professional amp 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 Edit DVCPRO compatibility mark Tracks on DVCPRO tape in Russian Panasonic AJ D455 VCR for professional video use with IEEE 1394 port and DV capabilityDVCPRO also known as DVCPRO25 and D 7 is a variation of DV developed by Panasonic and introduced in 1995 originally intended for use in electronic news gathering 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 for both 50 Hz and 60 Hz variants to decrease generation losses 12 Audio is available in 16 bit 48 kHz precision When recorded to tape DVCPRO uses wider track pitch 18 mm vs 10 mm of baseline DV 13 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 Edit DVCPRO50 compatibility mark Panasonic AJ D950 DVCPRO50 VCR Panasonic AJ D95DC VCRDVCPRO50 was introduced by Panasonic in 1997 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 was not required For example BBC used DVCPRO50 to record high budget TV series such as Space Race 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 2000 DVCPRO Progressive Edit DVCPRO Progressive markDVCPRO Progressive was introduced by Panasonic alongside DVCPRO50 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 14 15 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 16 The format was superseded by DVCPRO HD DVCPRO HD Edit DVCPRO HD compatibility mark Panasonic AJ HDX900 camcorderDVCPRO HD also known as DVCPRO100 and D 12 is a high definition video 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 It was introduced in 2000 17 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 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 with older DV DVCPRO formats When recorded to tape in standard play mode DVCPRO HD uses the same 18 mm track pitch as other DVCPRO flavors A long play variant DVCPRO HD LP doubles the recording density by using 9 mm 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 offered by Sony It uses a similar compression scheme but at higher bitrate DVCAM Edit DVCAM compatibility markIn 1996 Sony responded with its own professional version of DV called DVCAM 18 Like DVCPRO DVCAM uses locked audio which prevents audio synchronization drift that may happen on DV if several generations of copies are made 19 When recorded to tape DVCAM uses 15 mm track pitch which is 50 wider compared to baseline 13 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 Edit Main article Digital8 Digital8 is a combination of the tape transport originally designed for analog Video8 and Hi8 formats with the DV codec Digital8 equipment records in DV format only but usually can playback Video8 and Hi8 tapes as well Comparison of DV implementations Edit Feature 20 21 22 DV DVCAM DVCPRO DVCPRO50 DIGITAL S Digital8Suppliers Sony Panasonic JVC Canon Sharp and others Sony Ikegami Panasonic also Philips Ikegami Hitachi Panasonic JVC Sony Hitachi Bit rate Mbps 25 50 25Bit depth luma 8 chroma 8525 60 subsampling 4 1 1 4 2 2 4 1 1625 50 subsampling 4 2 0 4 1 1 4 2 2 4 2 0525 60 frame size 720 480 720 487 5 720 480625 50 frame size 720 576 720 583 5 720 576Audio frequency KHz 32 44 1 48 32 48 44 1 nonpro mode 48 32 44 1 48Audio mode Locked unlocked Locked Locked unlockedTrack pitch mm 10 SP 6 7 LP 15 18 plays 10 and 15 20 16 34Tape speed mm s 18 8 29 193 33 8 525 67 640 625 67 708 57 737 28 666Tracks per frame 525 10 625 12 25Progressive recording EditThis section does not cite any sources Please help improve this section by adding citations to reliable sources Unsourced material may be challenged and removed June 2023 Learn how and when to remove this template message 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 If the goal is progressive scan distribution like Web videos progressive scan DVD video or film out then no filtering is applied Video recorded with 2 2 pulldown and no vertical filtering is conceptually identical to progressive segmented frame 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 EditMagnetic tape Edit This section needs additional citations for verification Please help improve this article by adding citations to reliable sources in this section Unsourced material may be challenged and removed August 2016 Learn how and when to remove this template message MiniDV markDV was originally designed for recording onto magnetic tape Tape is enclosed into videocassette of four different sizes small medium large and extra large All DV cassettes use 1 4 inch 6 4 mm wide tape DV on magnetic tape uses helical scan which wraps the tape around a tilted rotating head drum with video heads mounted to it As the drum rotates the heads read the tape diagonally DV uses a 21 7 mm diameter head drum at 9000 rpm The diagonal video tracks read by the heads are 10 microns wide 23 13 Small cassettes 66 x 48 x 12 2 mm 24 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 These cassettes come in lengths up to about 14 20 8GB for 63 or 90min minutes of DV or HDV video 25 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 24 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 DVCAM cassettes in both miniDV and large sizeLarge or L size cassettes 125 1 x 78 x 14 6 mm 24 are close in dimensions to Betacam 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 Various DVCPRO cassettes in different sizesExtra large cassettes or XL size 172 x 102 x 14 6 mm 24 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 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 to deposit metal onto the tape 26 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 A disassembled MiniDV cassette Mini DV tape mechanism inside an early 2000s Panasonic Palmcorder Quarter for scale Cassette Formats DV DVCPRO DVCAMSmall S size MiniDV Only made MiniDV adapters Medium M size Large L size Extra Large XL size File based media Edit With proliferation of tapeless camcorder video recording DV video can be recorded on optical discs solid state flash memory cards and hard disk drives and used as computer files In particular Sony XDCAM family of cameras can record DV onto either Professional Disc or SxS memory cards Panasonic DVCPRO HD and AVC Intra camcorders can record DV as well as DVCPRO onto P2 cards Some Panasonic AVCHD camcorders AG HMC80 AG AC130 AG AC160 record DV video onto Secure Digital 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 camcorders can feed live DV stream over IEEE 1394 interface to an external file based recorder Video is stored either as native DIF bitstream or wrapped into an audio video container such as AVI QuickTime or MXF DV DIF is the raw form of DV video The files usually have extensions dv or dif DV AVI is Microsoft 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 27 and the CompactFlash based HVR MRC1K 28 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 29 QuickTime 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 EditNearly all DV camcorders and decks have IEEE 1394 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 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 30 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 31 or a Firewire to Thunderbolt adapter 32 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 All DV variants have a time code but some older or consumer computer applications fail to take advantage of it Usage EditThe 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 citation needed DVCPRO HD was the preferred high definition standard of BBC Factual 33 Films EditNotable films to use the DV format include Love amp Pop Hideaki Anno 1998 citation needed The Cruise Bennett Miller 1998 The Gleaners and I Agnes Varda 2000 Chuck and Buck Miguel Arteta 2000 The Gleaners and I Two Years Later Agnes Varda 2002 28 Days Later Danny Boyle 2002 34 Inland Empire David Lynch 2006 Iraq in Fragments James Longley 2006 Rec Jaume Balaguero amp Paco Plaza 2007 citation needed My First Kiss and the People Involved Luigi Campi amp Giacomo Belletti 2016 Application software support EditMost 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 Apple MOV The DV meta information is preserved in both file types being Sub timecode and Start Stop date times which can be muxed to Quicktime SMPTE standard timecode Most Windows video software only supports DV in AVI containers as they use Microsoft s avifile dll which only supports reading avi files Mac OS X video software support both AVI and MOV containers Mixing tapes from different manufacturers EditThere was considerable controversy solely based on hearsay over whether or not using tapes from different manufacturers could lead to dropouts 35 36 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 citation needed 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 37 unreliable source 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 dubious discuss 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 See also EditSIF Source Input Format CIF Common Intermediate Format References Edit The Consumer Electronics Hall of Fame Sony DCR VX1000 IEEE Spectrum IEEE Spectrum Technology Engineering and Science News 3 January 2019 Retrieved 27 June 2021 HV10 Canon Camera Museum global canon Retrieved 21 July 2016 Recording Helical scan digital videocassette recording system using 6 35 mm magnetic tape for consumer use PDF DV Q amp A Our Expert Answers Your Questions Videomaker magazine Videomaker Inc October 1999 a b DVCAM format overview PDF Archived from the original PDF on 28 September 2011 Digital Video and Field Order dvmp co uk fxguide vfx knowledge Art of Keying 24 March 2006 Archived from the original on 24 March 2006 The DV DVCAM amp DVCPRO Formats tech details FAQ and links adamwilt com Puhovski Nenad April 2000 DV A SUCCESS STORY www stanford edu Retrieved 26 August 2013 DV DIF Digital Video Digital Interface Format digitalpreservation gov 26 December 2011 DV format debian org Archived from the original on 7 January 2010 Retrieved 9 November 2009 The DV DVCAM amp DVCPRO Formats tech details FAQ and links adamwilt com a b c Tozer E P J 12 November 2012 Broadcast Engineer s Reference Book CRC Press ISBN 9781136024184 via Google Books Caporale Studios Shoots Feature Films with Panasonic 480p DVCPRO50 Camcorder dvformat com 480p production systems Archived from the original on 21 November 2010 AJ PD900WP Operating instructions PDF Archived from the original PDF on 20 July 2011 Retrieved 10 November 2009 Pizzi Skip Jones Graham 24 April 2014 A Broadcast Engineering Tutorial for Non Engineers CRC Press ISBN 9781317906834 via Google Books https cvp com pdf sony dvcam family pdf bare URL PDF BBC Training DV Tape Formats Archived from the original on 11 June 2011 Sony announces Digital8 video format Retrieved 12 September 2022 The DV formats tabulated Retrieved 12 September 2022 DV Technology Comparison Retrieved 12 September 2022 Trundle Eugene 18 June 2001 Newnes Guide to Television and Video Technology Newnes ISBN 9780750648103 via Google Books a b c d Media Recognition DV part 1 26 March 2012 Appendix B Data Rates and Storage Needs for Various Digital Formats The Filmmaker s Handbook A Comprehensive Guide for the Digital Age PDF a href Template Cite book html title Template Cite book cite book a website ignored help S B Luitjens S E Stupp J C Lodder Metal evaporated tape state of the art and prospects Journal of Magnetism and Magnetic Materials Volume 155 Issues 1a 3 1996 Pages 261 265 ISSN 0304 8853 https doi org 10 1016 0304 8853 95 00727 X HVR DR60 HDV hard disk recorder HVR MRC1K Memory Recording Unit Panasonic AG HMC80 operating instructions PDF Why is the DV input disabled on most digital camcorders sold in Europe 5 April 2001 Retrieved 1 February 2020 How to Capture DV video via USB dvmp co uk How to Capture DV video via Thunderbolt on Windows dvmp co uk hdmasters2007 com PDF 25 May 2011 Archived from the original PDF on 25 May 2011 Bankston Douglas 1 July 2003 Anthony Dod Mantle DFF injects the apocalyptic 28 Days Later with a strain of digital video TheASC com Retrieved 1 May 2007 DV Tape FAQ zenera com Adam J Wilt Adam Wilt s Video Tidbits adamwilt com The Truth About Tape LubricantExternal links EditAdam Wilt s DV page with in depth technical information Retrieved from https en wikipedia org w index php title DV amp oldid 1167717409, wikipedia, wiki, book, books, library,

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