A camcorder is a portable electronic device for recording video images and audio
onto an internal storage device. The camcorder contains both a video camera and (traditionally)
a videocassette recorder in one unit, hence its portmanteau name. This compares to previous technology
where they would be separate.
The earliest camcorders, developed by companies such as JVC, Sony, and Kodak, used analog videotape,
but since the mid-1990s (and even before that in professional markets), camcorders recording digital video
have become the norm.
Camcorders are often classified by their storage device: VHS, Betamax, Video8 are examples of older, videotape-based
camcorders which record video in analog form. Newer camcorders include Digital8, miniDV, DVD, Hard drive
and solid-state (flash) semiconductor memory, which all record video in digital form. The imager-chip is considered an analog
component, so the digital namesake is in reference to the camcorder's processing and recording of the video.
It should be noted that the take up of digital video storage in camcorders was an
enormous milestone. MiniDV storage allows full resolution video (720x576 for PAL,720x480
for NTSC), unlike previous analogue video standards. Digital video doesn't experience
colour bleeding, jitter, or fade, although some users still prefer the analog nature
of Hi8 and Super VHS-C, since neither of these produce the "background blur" or
"mosquito noise" of Digital compression. In many cases, a high-quality analog recording
shows more detail (such as rough textures on a wall) than a compressed digital recording
(which would show the same wall as flat and featureless).
The highest-quality digital formats, such as MiniDV and Digital Betacam, have the advantage over analog
of suffering little generation loss in recording, dubbing, and editing (MPEG-2 and MPEG-4
do suffer from generation loss in the editing process only). Whereas noise
and bandwidth issues relating to cables, amplifiers, and mixers can greatly affect analog recordings,
such problems are minimal in digital formats using digital connections (generally IEEE 1394, SDI/SDTI,or HDMI).
Both analog and digital can suffer from archival problems. Theoretically digital
information can be stored indefinitely with zero deterioration on a digital storage
device (such as a hard drive), but other types of media can have problems. Both
analog and digital tape formats are prone to deterioration over time, and since
digital often squeezes tracks only ~10 micrometers apart (versus ~500 ?m for VHS),
a digital recording is more vulnerable to wrinkles or stretches in the tape that
could permanently erase several scenes worth of digital data, but barely register
as "noise" on an analog tape. Even digital recordings on DVD are known to suffer
from DVD rot that permanently erase huge chunks of data. Thus the one advantage analog
seems to have in this respect is that an analog recording may be "usable" even after the
media it is stored on has suffered severe deterioration whereas it has been noticed
that even slight media degradation in digital recordings may cause them to suffer
from an "all or nothing" failure, i.e. the digital recording will end up being totally
un-playable without very expensive restoration work.
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