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Introduction


HDV is a high-definition variation of the DV video encoding specification that uses MPEG-2 compression to achieve the same data rate as the DV, DVCAM, and DVCPRO video encoding specifications. It was developed by Sony, Canon, JVC and Sharp and was introduced to the consumer market in 2003. HDV video can be captured in 720p, 1080i, and 1080p and can be recorded using MiniDV or Standard DVC cassettes. 

Physical Characteristics


Tape width
Tape composition
Cassette dimensions


Container dimensions


Identifying features


Common manufacturers/brands
Playback

Technical Characteristics


VersionHDV 720pHDV 1080iHDV 1080p
Record time




Record/playback speed


Bitrate19.7 Mbit/s25 Mbit/s
Bit depth


Colour sampling


Resolution




Compression



Techical standards


  1. The HDV specification has not been standardized but it is based on the DV specification and uses MPEG-2 encoding, which is standardized in ISO/IEC 13818:2015 generic coding of motion pictures and associated audio information.


Storage


Storage environment: temperature

Ideal: 40–54°F (4.5–12°C)

Acceptable: 55–60°F (13–15.5°C)

Storage environment: humidity30–50% RH
Container

HDV containers should pass the Photographic Activity Test (PAT) as specified ISO Standard 18916:2007

  • Plastic: Polyethylene, polypropylene, or polyester (a.k.a. Mylar D or Melinex 516). No PVC or acetate
  • Paper/Paperboard: If paper containers are necessary, they should be constructed from lignin-free, neutral pH paper/paperboard

Containers are acceptable if they:

  • Are clean and free of mould
  • Protect the media from dust and other contaminants
  • Are not introducing contaminants through degradation

Unacceptable containers must be replaced with clean, inert containers.

Orientation of tape in storageVertical on its end (like books)

Risk assessment


  1. Digital video material stored on magnetic videotape is considered to be at high-risk of loss or degradation.

    1. Polyester base film used in videotape is considered very stable.

    2. Other components of the videotape, including the binder, are considerably less stable and are more likely to be the cause of degradation.

    3. Format obsolesce, including lack of well-functioning playback equipment poses an equal or even greater risk than degradation, even with higher quality formats such as Digital Betacam

  2. Digital video material stored on magnetic tape should be appraised or re-appraised to determine the nature and signficance of video elements contained on the tape and whether the video elements have sufficient archival value to justify reformatting and long-term preservation as digital video files.

Types of damage and deterioration



Binder deterioration
DescriptionCommonly known as "sticky shed syndrome." Affected records will have a visible gummy or powdery residue on the surface of the tape. This can damage both the recorded material and playback equipment. Back-coated tapes are most affected by this type of deterioration. 
CausePolyester urethane is prone to moisture absorption which can cause the molecular structure of the binder to break down. This process is accelerated by high temperature and high humidity.
Remedy

Environmental conditioning: Moving the tape to a controlled storage environment (40°C / 20 to 25% Relative Humidity) may reverse the affects of hydrolysis over time.

Baking: Holding the tape at an elevated temperature (45°C to 55°C) for a brief period of time (up to 36 hours) can temporarily remove moisture and allow normal playback for a period of one to two weeks. Tapes should not be rewound before baking. 

Drop-out
DescriptionA brief signal loss caused by a tape head clog, missing magnetic oxide particles, tape defect, or debris on the tape or machine. These factors can reduce head-to-tape spacing and result in the appearance of white spots or streaks on playback. Multiple drop-outs per frame will result in a snowy appearance. 
Cause Tapes kept in dusty conditions will accumulate particulate matter, increasing the risk of drop-out. 
RemedyFlaking/missing magnetic oxide particles are an indication of tape deterioration. This type of drop-out cannot be corrected physically. 
Mould
DescriptionActive mould is generally moist while dormant mould is dry and dusty. Mould growths may be white, black, brown or mustard-coloured and usually have a pattered, fuzzy, or thread-like appearance. Mould can cause permanent damage to tapes over time if not removed. Fungus and mould is also a significant health hazard and affected materials should be handled using gloves and masks. 
CauseStoring tapes at high temperature and relative humidity levels can facilitate the growth of mould. 
RemedyMouldy tapes should be isolated from unaffected materials to prevent cross contamination. Store tapes at a temperature of 24°C in an environment with effective air circulation and less than 50% Relative Humidity. Loose mold can be vacuumed from the tape pack and then the tape should be treated with an appropriate fungicide.  
Stretching and breaking
Description

The elongation of parts of the tape, across the full width of the tape or -most likely- on one or the other side of the tape

The separation of tape into two or more pieces.

Causeusually results from either improper wind or from faulty equipment. May cause long-edge or curvature problems, and distort the signal, but the data can generally be retrieved from an analog tape, usually with a decrease in signal quality." Improper handling or use of playback equipment.
Remedy
Accidental recording
DescriptionCamera operators can accidentally record over pre-existing footage
CauseTape is set to "record mode" when it is inserted into camera or deck
RemedyEnsure tape is set to "safe mode" before inserting into camera or deck

Further Reading


Visit the /wiki/spaces/ALC/overview for further reading on /wiki/spaces/ALC/pages/1891631115

References


AMIA. "Video Preservation Factsheets." Accessed December 10, 2020. 

Avid. "Working With HDV." Accessed February 3, 2021. 

Bensinger, Charles. "Chapter 6: All about videotape." In The Video Guide, Second Edition, 71-75. Santa Barbara, California: Video-Info Publications, 1981. 

Bogart, John Van. "What Can Go Wrong With Magnetic Media?" In Magnetic Tape Storage and Handling: A Guide for Libraries and Archives. Washington, DC: The Commission on Preservation and Access, 1995. 

Casey, Mike. "FACET: Format characteristics and preservation problems." Bloomington, IN: Indiana University, 2007. 

Gibson, Gerald. D. "Magnetic tape deterioration: recognition, recovery and prevention." Paper presented at the IASA Conference, Perugia, August 26, 1996.

MediaCollege.com. "The HDV Video Format." Accessed February 3, 2021. 

Museum of Obsolete Media. "HDV (2003 – 2011)." Accessed February 3, 2021. 

Preservation Self Assessment Program. "Videotape: HDV." University of Illinois at Urbana-Champaign. Accessed February 3, 2021

Wheeler, Jim. "Videotape preservation handbook." 2002. 

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