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DVCPROHD is a format for recording high definition video. Developed by Panasonic, DVCPROHD can be considered a high definition variant of DV format. Depending on frame rate and frame size, DVCPROHD uses up to four times higher bitrate than DV.

To reduce amount of recorded data, horizontal resolution of images is reduced compared to broadcast high definition video. This horizontal compression is similar to but more significant than that of other HD formats such as HDCAM, HDV or AVCHD. On another hand, DVCPROHD uses higher quality 4:2:2 color sampling, compared to 4:2:0 or 4:1:1 color sampling used in lower-bitrate video formats.

DVCPRO HD horizontally compresses recorded images to 960x720 pixels for 720p output, 1280x1080 for 1080/59.94i or 1440x1080 for 1080/50i.

The final DCT compression ratio of DVCPRO HD is approximately 6.7:1. To maintain compatibility with HDSDI, DVCPRO100 equipment upsamples video during playback. A camcorder using a special variable-framerate (from 4 to 60 frame/s) variant of DVCPRO HD called VariCam is also available. All these variants are backward compatible but not forward compatible. 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.

DVCPRO cassettes are always labeled with a pair of run times, the smaller of the two being the capacity for DVCPRO50. A "M" tape can hold up to 66/33 minutes of video. The color of the lid indicates the format: DVCPRO tapes have a yellow lid, longer "L" tapes made specially for DVCPRO50 have a blue lid and DVCPRO HD tapes have a red lid. The formulation of the tape is the same, and the tapes are interchangeable between formats. The running time of each tape is 1x for DVCPRO, ½x for DVCPRO 50, ½x for DVCPRO HD EX, and ¼x for DVCPRO HD, since the tape speed changes between formats. Thus a tape made 126 minutes for DVCPRO will last approximately 32 minutes in DVCPRO HD.

Presently, only Panasonic camcorders and tape recorders can record and play back DVCPROHD content.

DVCPROHD 720p
HDV 720p closely matches broadcast 720p progressive scan video standard in terms of scanning type, frame rate, frame size, aspect ratio and data rate. First HDV 720p camcorders could shoot only with 24, 25 and 30 frames per second, but later models remedied this issue, providing true 50p/60p recording modes.

Presently, JVC is the only manufacturer of HDV 720p camcorders. JVC was the first to release an HDV camcorder, the handheld GR-HD1. Later JVC shifted its HDV development to shoulder-mounted cameras.

A common misconception is that JVC developed a proprietary extension to HDV called ProHD, featuring film-like 24-frame/s progressive recording mode and LPCM audio, for professional use. JVC has clarified that ProHD is not a video recording format, but "an approach for delivering affordable HD products" and a common name for "bandwidth efficient professional HD models".

DVCPROHD 1080i
Being a major manufacturer of interlaced video equipment, Sony adapted HDV, originally conceived as progressive-scan format by JVC, to interlaced video. Instead of using 1920x1080 frame size with square pixels HDV 1080i utilizes 1440x1080 frame with 1.33 pixel aspect ratio. Such downsampling is not unique to HDV 1080i, it is used in other high definition video recording standards like HDCAM or DVCPROHD to reduce the amount of information to be recorded.

Interlaced video has been a useful compromise for decades due to its ability to display motion smoothly while reducing recording and transmission bandwidth. Interlaced video is still being used in acquisition and broadcast, but interlaced display devices are being phased out. Modern flat-panel television sets that utilize plasma and LCD technology are inherently progressive. All modern computer monitors use progressive scanning as well. Interlaced video must be converted to progressive before it is displayed on a progressive-scan device. The process of converting interlaced video into progressive is known as deinterlacing. Progressive-scan television sets employ built-in deinterlacing circuits to cope with interlaced broadcast signal, but computers rarely have this capability. Interlaced video often exhibit ghosting or combing artifacts when watched on a computer.

Some HDV 1080i camcorders are capable of recording progressive video within an interlaced stream, provided that the frame rate does not exceed half of the field rate. The first HDV 1080i camcorder to implement such Progressive Scanning was the Sony HVR-V1. To preserve compatibility with interlaced equipment the HVR-V1 records and outputs video in interlaced form. 25-frame/s and 30-frame/s progressive video is recorded on tape using progressive segmented frame (PsF) technique, while 24-frame/s recording employs 2-3 pulldown. The camcorder offers two variations of 24-frame/s recording: "24" and "24A". In "24" mode the camera ensures that there are no cadence breaks for a whole tape, this mode works better for watching video directly from the camera and for adding "film look" to interlaced video. In the "24A" mode the camera starts every clip on an A frame with timecode set to an even second margin. Several editing tools, including Sony's own Vegas, are capable of processing 24A video as proper 24 frames/s progressive video.

Prior to the HVR-V1, Sony was offering Cineframe, essentially an interlaced-to-progressive converter, to simulate film-like motion. The conversion process involved blending and discarding fields, so vertical resolution of the resulting video suffered. Motion, produced in the 24-frame/s variant of Cineframe was too uneven for professional use. The same or better film look effect can be achieved by converting regular interlaced video into progressive format using computer software.

In 2007 Canon commoditized progressive scanning, releasing the HV20 camcorder. The version for 50 Hz market featured PF25 mode with PsF-like recording, while the version for 60 Hz market had PF24 mode, which utilized 2-3 pulldown scheme. The HV30, released in 2008, implemented additional PsF-like PF30 mode for 60 Hz markets. Output is performed via component, HDMI and FireWire in interlaced form.

To achieve full vertical resolution without introducing interlace artifacts the progressive scan video must be properly deinterlaced. 25P and 30P video must be deinterlaced with "weave" or "no deinterlacing" algorithm, which means joining two fields of each frame together into one progressive frame. 24P video must go through film-mode deinterlacing also known as inverse telecine, which throws out judder frames and restores original 24-frame/s progressive video.

HDV 1080p
The original 1080-line HDV specification defined interlaced recording only, which is suitable for television broadcast. As users have become increasingly interested in digital cinematography and in web videos, progressive recording became a necessity. In response to this need, capability for native progressive recording has been added to the 1080i HDV specification. Progressive recording modes are optional for 1080i HDV devices, which means that not every HDV 1080i camcorder or deck is capable of recording or playing back native progressive video. Because HDV 1080i specification now includes both interlaced and progressive recording modes, in recent publications it is often called HDV 1080 or 1080-line HDV, but the official name still bears the "i" suffix.

HDV camcorders capable of native 1080-line progressive video record it at rates of 24 frame/s (actually 23.98 frame/s) and 30 frame/s (actually 29.97 frame/s) for 60 Hz markets, and at 25 frame/s rate for 50 Hz markets. Video is output as true progressive video via an i.LINK/Firewire port. Output through other ports is performed in interlaced mode to preserve compatibility with existing interlaced equipment.

The first 1080-line HDV camcorder to offer recording in native progressive format was the Canon XL H1, introduced in 2006. It was followed by the the XH-G1 and XH-A1. When shooting in progressive mode, also known as Frame mode, the camcorders generate progressive video from interlaced CCD sensors. Vertical resolution of the resulting video is about 25% lower than theoretically possible because of row-pair summation, but is still higher than the resolution of a single field. Video shot in Frame Mode is recorded to tape according to HDV native 1080p specifications.

In 2008 Sony released its own models capable of native progressive recording: the HVR-S270, the HVR-Z7 and the HVR-Z5. Sony claims superiority over Canon models by saying that native progressive recording has been called 24F/25F/30F in some camcorders, which actually use interlaced CCD imagers. Sony stresses that the progressive-scan CMOS sensors used in its new models create true 1080p images, meaning that the signal is processed as progressive all the way from capture to encoding to recording onto tape to output.

In 2009 Canon released the HV40. Its 60 Hz variant became the first consumer HDV camcorder to feature 24-frame/s native progressive recording. Like the aforementioned Sony models, the HV40 uses progressive-scan sensor.

Sony designed Native Progressive Recording logo for the devices that are capable of native progressive recording and playback. Canon has no special logo to identify cameras that can record in "F" modes, though the HV40 camcorder bears 24p native progressive mark. Despite differences in branding, 24F/25F/30F modes offered by Canon and Native Progressive Recording offered by Sony are compatible.

Other HDV devices capable of reading and recording in native progressive 1080-line format include the Sony HVR-M15AU, HVR-25AU, HVR-M15AE, HVR-25AE and HVR-M35 HDV videocassette recorders, and the Canon HV20/HV30 camcorders when used in tape recorder mode.

Compatibility between brands
Generally, HDV devices are capable of playing and recording in DV format, though this is not required by HDV specification. Many HDV devices manufactured by Sony are capable of playing and recording DVCAM tapes. 1080-line devices generally are not compatible with 720-line devices, though some standalone tape decks accept both HDV formats. Devices that can play and record native 1080p video can play and record native 1080i video, however the opposite is not always the case.

HDV camcorders are usually offered with either 50 Hz or 60 Hz scanning rate, but some models can be made switchable for "world" capability. In particular, Canon XH-A1/G1 models and third-generation Sony models such as HVR-S270, HVR-Z5 and HVR-Z7, can be upgraded.

HDV compression
HDV video is compressed with MPEG-2 encoder and is wrapped into transport stream. HDV audio is compressed using MPEG-1 Layer 2 compression scheme.

MPEG-2 is an established compression method used in DVD-Video and in many digital TV broadcast formats, in particular ATSC. HDV 1080i uses a recording data rate of 25 Mbit/s while HDV 720p records at 19.7 Mbit/s. In both cases the data rate is constant because the recording media — tape — is transported with constant speed. Constant data rate limits the video quality in scenes with lots of detail, rapid movement or other complex activity like flashing lights. Such scenes may exhibit visible artifacts such as blockiness or blurring, depending on the amount of movement and on the algorithm employed in the encoder.

MPEG-1 Layer 2 compression used for audio allows reducing the audio bitrate to 384 kbit/s, compared to 1536 kbit/s for DV video and 1411 kbit/s for audio CDs. In most cases, HDV audio is not a significant limiting factor and is considered perceptually lossless.

Use of HDV in broadcast television
HDV is accepted with varying restrictions for broadcast TV use. It has been used for shows like "Deadliest Catch" and "MythBusters", and was used in the TV series "JAG" for scenes where larger HD cameras would have been impractical.

The BBC currently considers HDV a "non-broadcast domestic HD format," but accepts HDV footage for up to 25% of HD programming content with advance approval.

The Discovery HD Theater accepts content sourced from 1080-line HDV camcorders, but limits it to 15% of a whole program. Producers wishing to use HDV are required to submit an approved postproduction path outlining their handling of the footage in the editing process. However, the main Discovery Channel's HD simulcast has fewer or no guidelines and accepts a mix of XDCAM HD, HDV and AVCHD for the length of a program.

The PBS requires that for HD broadcast "the camera must use three CCD chips, each with at least a 1/2” diagonal and a minimum resolution of 1280 x 720. PBS does not list specific encoding formats and data rates, but requires that compression artifacts "must not be obvious when viewed on an HDTV monitor". For certain circumstances PBS allows usage of "less than full broadcast quality equipment". For example, the Art Wolfe's TV series "Travels to the edge" is being produced for PBS in HDV format using Canon XL-H1 camcorders.

Guiding Light, the longest-running soap opera in production in television and radio history, broke away from traditional three-sided sets and pedestal-style cameras in 2008, choosing the handheld Canon XH-G1 for shooting on practical locations.

Editing HDV
HDV footage can be effectively edited by most modern non-linear editors on fast personal computers. Performance may be reduced compared to other video formats due to both the high resolution and interframe compression, both of which require computers to work harder when calculating editing effects. Performance can be improved by converting HDV to alternative "intermediate" codecs prior to editing, including Cineform Aspect HD, Edius HQ and Apple ProRes 422. There are many advantages to editing HDV using an intermediate codec rather than the native MPEG2 file, however the trade-off is that the file size is substantially increased.

Distributing HDV
The native physical format for HDV is a MiniDV or DV cassette. Because HDV is recorded in digital form, the original content can be copied onto another tape without quality degradation.

For editing in a computer-based editing system the tape can be captured onto a computer. Depending on software, either the whole tape is captured into one contiguous file, or separate files are created for each take. The way files are named depends on capturing software.

Some systems convert HDV video into proprietary intermediate format on the fly while capturing, while other systems capture video stream as is. In the latter case, the disk files contain the same exact data that has been recorded on tape, without re-encoding or quality degradation.

After editing, HDV video can be recorded or printed back to MiniDV tape. Such tapes are often accepted by local television stations, though many organizations prefer the submissions to be delivered in a higher-end format like Digital Betacam, HDCAM or D5 HD.

For consumer use, HDV-sourced video can be delivered on a Blu-ray Disc, can be converted to AVCHD and delivered on an AVCHD disc, or can be downconverted to DVD-Video.

For distribution over the Internet interlaced video has to be deinterlaced, because most computer-based video players support only progressive-scan video.

Canon


Canon entered the HDV market in September 2005, with the Canon XL H1, a professional-oriented modular camera system with interchangeable lenses, HD-SDI output, and three 1440x1080 1/3" CCDs. In July 2006, Canon announced their XH A1 and XH G1 models, which use the same sensor as the XL-H1 but in a smaller form factor with a (non-changeable) fixed lens. Canon then introduced the consumer oriented Canon HV10, a compact unit with a single 2.76 megapixel CMOS sensor.

In April 2007 Canon released the updated Canon HV20 which adds a 24p Progressive + film mode where the imager captures 24 progressive frames per second, but records to 1080i60 HDV using a built-in 3:2 pulldown (telecine) process, to remain compatible with consumer level editing suites.

The 2008 update Canon HV30 got black body color instead of the HV20's grey one, and added a progressive 30p mode to simplify video-uploads to online sites such as YouTube or Motionbox.

In 2009 Canon announced the Canon HV40 which is identical to HV30 except it is now capable for native progressive 24p recording without applying 3:2 pulldown (thus without encoding it into a 1080i60 stream.)

JVC


In 2003 JVC release the first HDV camcorder — the handheld GR-HD1. The camcorder offered standard DV recording mode, HDV 720p30 and HDV 480p60. The HDV modes used the older Rec. 601 standard for color space, rather than the newer Rec. 709 standard intended for high-definition video. The imager of the GR-HD1 used a single 1/3" CCD sensor instead of a 3CCD setup, another unusual choice discouraging professional use.The GR-HD1 was not popular in either the consumer or semi-professional market, and JVC later shifted its HDV development to professional shoulder-mounted cameras.

The shoulder mount GY-HD100 camcorder was released in 2005 and featured 3CCD imaging system with native 720p resolution, interchangeable lens and 24 frame/s recording. Because of the latter feature this camcorder became popular for shooting "digital movies". The updated version, GY-HD110, provides several updates and fixed split-screen effect found on some GY-HD100 cameras.

The GY-HD200, released later, offered 50p/60p recording, 720p-to-1080i converter and Anton Bauer professional battery with mount.

The GY-HD250 simplified multi-camera recording by providing genlock and time code input/output. HD/SD-SDI output allowed to record uncompressed video.

Sharp
Sharp is the only member of the HDV Consortium that has not produced an HDV camcorder or a videocassette recorder. The closest Sharp has ever got in supporting HDV standard is the AQUOS DV-ACV52 digital video player. The player supports HDV video, though it does not have a tape transport. Instead, it allows playback and dubbing of DV/HDV video from a camcorder connected to the player via a FireWire connector.

Sony


Sony specializes in 1080i HDV equipment and makes products for both 60 Hz and 50 Hz markets. Traditionally, Sony uses suffix "E" to identify 50 Hz models, and suffix "U" or no suffix at all to identify 60 Hz models. Models listed below are specified without suffixes.

In September 2004 Sony released the first HDV 1080i camcorder, the HDR-FX1. Its professional version, the HVR-Z1, came with XLR audio inputs and 44 additional features. Most notably, the HVR-Z1 was switchable between 50 Hz and 60 Hz scanning to cater for the different scanning rates used in different markets.

In the middle of 2005 Sony released its first consumer HDV model, the HDR-HC1, which had a single CMOS sensor, electronic stabilization system and was capable of recording in DV and HDV 1080i modes. Its professional version, the HVR-A1, added a second accessory shoe in place of the flash, XLR audio inputs, additional recording options, larger eyecup and larger lens hood.

In 2006 Sony replaced the HDR-HC1 with the smaller and cheaper HDR-HC3, which featured an incrementally improved CMOS chip, but omitted some features of its predecessor. The HDR-HC3 was replaced by the HDR-HC5 which used the same CMOS chip as the HDR-HC3, and added an option of recording in xvYCC color space. The replacement model, the HDR-HC7 came with a higher pixel count CMOS sensor and with a microphone input. Like the HDR-HC5, the HDR-HC7 could also record xvYCC. In 2008 the HDR-HC7 was replaced with the HDR-HC9.

In 2006, Sony added two new models to its upscale HDV lineup: the "advanced amateur" HDR-FX7 and its professional cousin, the HVR-V1. The progressive-scan CMOS sensors of these models resolve full 1080 lines of vertical resolution. The HDR-FX7 records interlaced video only, while the HVR-V1 offers the choice of shooting interlaced or progressive video. Progressive video is converted to interlaced using pulldown when recorded on tape.

In August 2007, Sony introduced the shoulder-mounted version of the HDR-HC7, the HVR-HD1000. It has a lens similar in size to that of the HVR-Z1 or HVR-V1.

In November 2007, Sony announced the HVR-Z7 handheld camcorder and the HVR-S270 shoulder-mounted camera. Both use the same three 1/3" ClearVid CMOS sensors and attain light sensitivity similar to that of the venerable DSR-PD170 while offering HDV recording in native interlaced, progressive scan and native progressive modes. The Z7 has 2 XLR audio inputs and HDMI output while the S270 has 4 XLR inputs and features HD-SDI output. Presently the HVR-S270 is the only HDV camcorder capable of recording onto full-size DV cassettes.

In 2008 the HDR-FX1 and the HVR-Z1 were replaced with the HDR-FX1000 and the HVR-Z5, respectively. The major changes include utilizing CMOS sensors instead of CCD, and progressive mode shooting. the FX1000 records progressive scan video using pulldown, while HVR-Z5 offers native progressive recording.

In November 2008 Sony restarted production of the HDR-FX7 camcorder, which had been discontinued a year earlier. Offered for almost half the original price, the HDR-FX7 bridged the gap between the HDR-HC9 and the FX1000.

In summer 2009 Sony discontinued the HDR-HC9 without offering a replacement model. According to the new corporate policy, the consumer market will be served exclusively by AVCHD format, while HDV equipment will be offered for prosumer and low-end professional markets.

The future of HDV
Presently, HDV remains the latest video recording standard to use magnetic tape as recording media. No new tape-based standards have been proposed since the introduction of HDV in 2003. At the same time, tapeless video recording formats such as DVCPRO P2, XDCAM and AVCHD have gained broader acceptance. The trend towards tapeless workflow is accelerated with increased capacity and reduced cost of non-linear storage solutions like hard disk drives, optical discs and solid-state memory.

In 2009 Sony stopped offering consumer HDV camcorders in North America and Europe, making AVCHD format of choice for the consumer market. HDV is presently relegated to prosumer and low-end professional use, while XDCAM and XDCAM EX are offered for higher-end professional applications. In 2008 and 2009 Sony released several new professional models of HDV camcorders, with significant improvements in performance and features compared to outgoing models. During the same period Canon did only minor upgrades to its professional and consumer HDV lineups, mostly in firmware. JVC did not release new HDV models in 2009.

To address the trend towards tapeless workflow JVC and Sony offer on-camera recording units, which convert an HDV camcorder into a hybrid system capable of recording both onto tape and onto file-based media. JVC offers the HDD-based DR-HD100 and MR-HD100 on-camera recorders and the SxS-based KA-MR100G recorder. Sony offers the HDD-based HVR-DR60 and the CompactFlash-based HVR-MRC1K recorders. All the above recorders except for the KA-MR100G are connected to a camcorder via FireWire. Some models use a standard FireWire cable while other integrate through a dedicated connector. Because these devices record video over FireWire, the format and quality of the recorded video is exactly the same as when written to tape. The KA-MR100G connects via a specially designed dock and records in XDCAM EX format.