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BOOT CAMP 178 (07/06//01)
CAMCORDERS AND COMPUTERS part
1
Home computers and camcorders have much in common. They both
came into being in the early 1980s, early models were expensive but rapid
take-up by consumers brought prices down. They've become progressively smaller
and more sophisticated and over the years various formats and systems have come
and gone. This week we'll see how much closer the two technologies have become
in recent years, next week we'll see what's in it for you and put theory into
practice.
Numerous attempts have been made to bring camcorders and
computers together, with varying degrees of success. It has become something of
a crusade in some quarters of the PC and consumer electronics industries and
amongst enthusiasts and professionals, but what's the point? The trouble with
camcorders is that they make it all too easy. Video tapes are cheap and last
ages with the result that a lot of home video movies are overlong, boring and
full of gaffes. After an initial flurry of interest and several tapes filled
with Fido and the kids cavorting in the back garden many camcorders end their
days gathering dust in the bottoms of drawers and wardrobes.
This never happened with cine cameras of course. Films only
lasted a few minutes and processing was expensive so home movie makers were
forced to be economical and choose their shots carefully. Editing cine film was
easy too, often involving nothing more complicated than a pair of scissors and
some sticky tape.
Editing video recordings is much more complicated and in the
early days the only way to do it was to copy selected scenes onto a VHS VCR, a
technique known as 'crash editing'. Copying video results in a big loss of
quality. In fact it wasn't that good to begin with, in the case of analogue
camcorders using the VHS/VHS-C and 8mm formats ('low-band' systems) and edited
recordings usually looked pretty awful.
Things improved slightly during the late 80s and early 90s
with the arrival of the Super VHS-C and Hi8 ('high-band') formats and better
VCRs, with care edited copies could look as good as low band originals, and at
about this time the PC began to have an impact.
Some camcorders, notably those made by Sony and Panasonic had
'edit terminals' that allowed the editing process to be automated and controlled
by devices called edit controllers and subsequently PCs. Edit control is
something PCs are very good at. The software instructs the camcorder to play
back selected scenes in a pre-determined order – to cut out the wonky bits --
and at the same time the PC controls the record/pause function on a VCR (usually
via an infra-red 'wand'), enabling sequences to be accurately defined and
seamlessly joined together. The better stand-alone and PC edit controllers can
read tape counter data and 'time codes' on recordings made on some high-end
camcorders so edits could be very accurate indeed, close to professional
standards.
Several early home computers, notably Amiga and Atari models
had video output sockets and programs were developed for creating titles and
graphics that could be overlaid or superimposed onto moving video (using gizmos
called 'genlocks'). However PCs still had no active involvement in the editing
process – other than acting as controllers and graphics generators -- until the
late 1990s, following the introduction of the multi-media friendly Pentium
series of processors. It became easier to get moving video from camcorders into
PCs, though it still required a lot of processing power and the data had to be
highly compressed. This degraded quality, resulting in images being shown in
small video 'windows' or larger displays with slow jerky movement and impaired
resolution. Nevertheless, once video data was on the PC's hard disc it was easy
to edit scenes together and combine them with special effects to create quite
impressive looking productions. However, the reduction in picture quality meant
that 'movies' could only be shown on PC screens, which was fine for things like
multimedia content on CD-ROMs and presentations but it wasn't good enough to
export back to analogue tape or for showing on a normal TV.
Faster PCs and the introduction of the high-speed USB
(Universal Serial Bus) communications port on PCs have helped to improve picture
quality but for the most part once video is in the PC it stays there.
Then in 1995 the change began when Sony and JVC introduced
the first digital camcorders (digicams) using the Digital Video Cassette (DVC)
format. In addition to recording near broadcast quality pictures and sound
virtually all 'DV' camcorders are fitted with an IEEE 1394 high speed serial
data port, better known to enthusiasts as a FireWire or iLink connection.
FireWire was the vital link that allowed PCs and camcorders to communicate with
one another, exchanging digital data in much the same way as other PC
peripherals like printers and modems. More importantly, since the pictures and
sound remains in the digital domain there is no reduction in quality when
copying or editing.
However, at first things didn't go quite as smoothly, or
quickly as everyone one had hoped. To begin with the necessary FireWire
interface cards required by PCs to hook up with digicams were expensive,
moreover only the fastest PCs with lots of memory and big and fast hard disc
drives could handle video data from a digicam. To complicate matters further
digicams sold in the EU were fitted with output only FireWire ports, which meant
finished recordings couldn't be exported from the PC back onto tape without
loosing quality, so they could be shown on an ordinary TV. (This is due to
archaic EU regulations that classify camcorders with video input facilities as
VCRs and therefore subject to higher tariffs and lower quotas).
Within the past couple of years even faster processors, a
reduction in the cost of memory and a dramatic increase in the size of hard disc
drives has meant that even so-called 'entry-level' PCs are capable of editing
video footage shot on a digicam. The cost of FireWire input cards has fallen to
well below £100 and they are fitted as standard on some desktop models and a
growing number of laptops. Allied to the big drop in the cost of digicams (the
cheapest models are now selling for less than £500), and many more models with
FireWire inputs, producing professional quality video movies at home is now
possible.
Next week – Camcorders and Computers, part 2
JARGON FILTER
EDIT CONTROLLER
Stand-alone device (or PC) that controls the playback of a
camcorder or video tape recorder, so that selected scenes can be joined
together
INFRA-RED WAND
Device, attached to an edit controller or PC that emits the
same sort of infra-red signals as a remote control handset, to operate a
VCR.
TIMECODE
Unique code assigned to each frame of a video movie, enabling
edit controllers to make 'frame-accurate' cuts and joins between scenes
TOP TIP
In last week's Top Tip we mentioned the dreaded 'Kiosk Mode',
where a web site opens a full screen browser window without any toolbars, menus,
minimise or close buttons. You are stuck with it, unless you know the Ctrl + W
or Alt + F4 shortcut to get rid of it. Kiosk mode does have its uses however.
For example, if you are using Internet Explorer to display web pages on a PC at
an exhibition or AV presentation and you don't want all the toolbars and other
gubbins taking up screen space. Here's how to force Internet Explorer into Kiosk
mode. Go to Run on the Start menu and type 'iexplore –k' (without the quotes),
followed by the address of the page or web site you want to display. If you just
type 'iexplore –k' Internet Explorer will open on your selected home page.
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