Monday 26 March 2012

Media Recognition: DV part 3

DVCAM (encoding)
Type:
Digital videotape cassette encoding
Introduced:
1996
Active:
Yes, but few new camcorders are being produced.
Cessation:
-
Capacity:
184 minutes (large), 40 minutes (MiniDV).
Compatibility:
DVCAM is an enhancement of the widely adopted DV format, and uses the same encoding.
Cassettes recorded in DVCAM format can be played back in DVCAM VTRs (Video Tape Recorders), newer DV VTRs (made after the introduction of DVCAM), and DVCPRO VTRs, as long as the correct settings are specified (this resamples the signal to 4:1:1). DVCAM can also be played back in compatible HDV players.
Users:
Professional / Industrial.
File Systems:
-
Common Manufacturers:
Sony, Ikegami.

DVCAM is Sony’s enhancement of the DV format for the professional market. DVCAM uses the same encoding as DV, although it records ‘locked’ rather than ‘unlocked’ audio. It also differs from DV as it has a track width of 15 microns and a tape speed of 28.215 mm/sec to make it more robust. Any DV cassette can contain DVCAM format video, but some are sold with DVCAM branding on them.

Recognition
DVCAM labelled cassettes come in large (125.1 x 78 x 14.6 mm) or MiniDV (66 x 48 x 12.2mm) sizes. Tape width is ¼”. Large cassettes are used in editing and recording decks, while the smaller cassettes are used in camcorders. They are marked with the DVCAM logo, usually in the upper-right hand corner. 


HDV (encoding)

Type:
Digital videotape cassette encoding
Introduced:
2003
Active:
Yes, although industry experts do not expect many new HDV products.
Cessation:
-
Capacity:
1 hour (MiniDV), up to 4.5 hours (large)
Compatibility:
Video is recorded in the popular MPEG-2 video format. Files can be transferred to computers without loss of quality using an IEEE 1394 connection.
There are two types of HDV, HDV 720p and HDV 1080, which are not cross-compatible.
HDV can be played back in HDV VTRs. These are often able to support other formats such as DV and DVCAM.
Users:
Amateur/Professional
File Systems:
-
Common Manufacturers:
Format developed by JVC, Sony, Canon and Sharp.


Unlike the other DV enhancements, HDV uses MPEG-2 compression rather than DV encoding. Any DV cassette can contain HDV format video, but some are sold with HDV branding on them. 

There are two different types of HDV: HDV 720p (HD1, made by JVC) and HDV 1080 (HD2, made by Sony and Canon). HDV 1080 devices are not generally compatible with HDV 720p devices. The type of HDV used is not always identified on the cassette itself, as it depends on the camcorder used rather than the cassette.

Recognition 
HDV is a tape only format which can be recorded on normal DV cassettes. Some MiniDV cassettes with lower dropout rates are indicated as being for HDV, either with text or the HDV logo. These are not essential for recording HDV video. 


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