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MPEG (“Moving pictures expert Group”): three video formats, MPEG 1, 2 and 4.
MPEG-l: Old, supported by everything (at least up to 352x240), reasonably efficient. A good format for the web.
MPEG-2: A 0uped-up version of MPEG-l, with better compression. 720x480. Used in HDTV, DVD, and SVCD.
MPEG-4: A family of codecs, some of which are open, others Microsoft proprietary. MPEG spin-offs: mp3 (for music) and Video CD.
There are four levels of quality in videotape formats: consumer, prosumer, industrial, and broadcast professional. Each format has its place in the videotape marketplace. The production and delivery requirement determines which videotape format we use. Naturally, a project for home use will have completely different requirements than a project going out for a network broadcast.
Tape generation loss is an important aspect to be considered when dealing with analogue videotape formats. Let us understand how tape generation loss happens. During the linear editing process, there is a loss of video quality as the image goes through the various editing and dubbing phases. Our first generation videotape will look beautiful during playback, but if the tape is edited using tape-to-tape editing process (linear editing), the final product will be second or third generation. By the time it is dubbed out for duplication, and then copied for distribution, the quality of the image does not remain as good because it is now fourth or fifth generation. This idea also pertains to non-linear video editing, in that, the more compression added to the video, the lower the quality of the image. This is all the more acute if the tape is analogue.
Some formats such as S-VHS may look very good in the first video generation, but these quickly lose quality through repeated dubs. The 3/4" SP tape format holds the image quality much better when going through the same editing processes.
So, the rule of thumb is to always start with the highest quality video format possible. Exhibit 11.1 shows the various videotape formats prominently in vogue among various levels of professionals.
Here are some terms that you should be familiar with in order to work with video:
Analogue tape Videotape that records a representation of a continuous electronic signal.
Composite video All colour, luminance, and synchronising information is carried together as part of the same signal. Composite video was the norm until the early 1990s.
Component video with component video, the luminance (black and white levels) and chrominance (colour information) are transmitted as separate signals. The picture quality is superior to composite video.
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Name VHS and S-VHS
System Analogue
Dates in use VHS-1976 to present; S-VHS1987 to present
Tape width 1/2"
Purpose Mainly for home/consumer use
Name 3/4" U-matic (aka 3/4" inch or U-matic),
3/4" U-matic SP (also known as 3/4" SP or U-matic SP)
System Analogue
Dates in use 3/4" U-matic-1971 to present; 3/4" U-matic SP-1986 to present
Tape width 3/4"
Also available U-matic Hi-band. Now almost phased out.
Purpose For industrial/broadcast purposes
Name Betacam and BetacamSP (aka Beta)
System Analogue
Dates in use Betacam-1982 to present; BetacamSP- 1986 to present
Tape width 1/2"
Also available Digi-beta
Purpose For industrial/broadcast purposes
Name Video8 (aka 8mm) and Hi8
System Analogue
Dates in use Video8-1984 to present; Hi81989 to present
Tape width 5/16" (8mm)
Purpose For amateur use
Name MiniDV System Digital
Dates in use 1995 to present
Tape width 1/4"
Purpose For both prosumer and amateur use; mostly used in educational institutions for training purposes; occasionally used for broadcast purposes
Name DVC Pro (also known as D7)
System Digital
Dates in use 1995 to present
Tape width 1/4"
Purpose Broadcast use
Name DVCAM System Digital
Dates in use 1995 to present
Tape width 1/4"
Purpose Broadcast use
Name Betamax System Analogue
Dates in use 1975 to late 1980s in the US
Tape width 1/2"
Purpose Used before/along with VHS, now phased out
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