Page 90 - DCAP303_MULTIMEDIA_SYSTEMS

Multimedia Systems

notes Although the concept of “live” may have exciting connotations, recording a production has many
advantages.

1. The length of a program or segment can be shortened or lengthened during editing,
2. Mistakes on the part of the talent or crew can be corrected, either by restarting the show,
or to some degree during post-production,
3. Program segments can be reorganized and rearranged for optimum pacing and dramatic
effect,
4. Program content can be embellished through the use of a wide array of editing and visual
effect techniques,

5. Production costs can be saved by scheduling production talent, crew and production facilities
for optimum efficiency, and

6. Once recorded, programs can be time-shifted or played back to meet the needs of time
zones and the programming preferences of local station.

5.6.1 videotape recording process
Although videotape has been phased out at most TV stations in favour of recoding on hard disks
or solid-state devices, it is widely in archival storage.
Videotape resembles audiotape in its makeup. It consists of a strip of plastic backing coated with
a permanent layer of microscopic metal particles embedded in a resin base. These particles are
capable of holding a magnetic charge.
Video recording revolutionized TV production.
Two inch wide videotape (pictured at the left) was the first practical video recording medium and
one that was used for several decades. Since it used four video heads to scan a complete video
picture on 2 inch wide tape, this system was referred to as the 2 inch quad system.
At the other end of the size spectrum was the Hi8 camcorder (right) that used videotape that is
only 8 mm wide.
To record very high frequencies associated with video, not only must the tape be moving, but
also the heads, themselves, must spin over the surface of the tape otherwise you did not get high
quality video.

5.6.2 Disk-based recording
DVD
In 1997, the DVD was introduced. (The initials stand for both digital versatile disk and digital
videodisk.)
Although DVDs resemble audio CDs, they are capable of holding much more information—up
to 17 GB of data.
To achieve capacities up to this level some innovations were added to the standard audio CD
approach.

First, it is possible to record at two disk surface levels on the same side of the disk. For even greater
a storage capacity both sides of the disk can be used.
Red light lasers were originally used, but the recording-playback density of data advanced in
the early 2000s with the introduction of lasers using a shorter wavelength blue light. Hence, the
name, Blu-ray.

84 LoveLy professionaL University