The recording format and encoding are different; NTSC is recorded at 29.94
frames per second, PAL and SECAM (Asia) are recorded at 24, and film at 14.
In a digital environment the algorithms used to encode that data are
completely different. I wouldn't claim to be an expert but I spent 4 years
building, coding, and testing digital video servers. Just about any TV
station that advertises digital studios, and 95% of the movies coming out of
Hollywood use gear I worked on.
Unfortunately, the impending change to HD could have cleared up a lot of
problems but none of it will be going away. The 29.94 FPS that NTSC uses
was based on the frequency of a readily available oscillator used for the
first B&W TVs. When color was invented they didn't want to obsolete the
B&Ws so they retained the same crystal. The odd rate is compensated for by
dropping one frame every minute except every tenth except every hour except
every tenth hour, (get the picture?). It is a real PITA to code. Since all
HD transmissions will need to be down converted to work on standard TV and
all standard transmissions need to be up converted to work on an HD set this
was the perfect time to change some of the legacy problems but they didn't.
The US Congress has passed a deadline of 2007 for the conversion of all
broadcasts to HD so that the analog frequencies can be sold to cellular and
other users. It was to be a staged rollout by market but it is going much
slower than planned.
Sorry, that is probably more than anyone wanted to know. But the moral of
the story is that they are recorded differently so not only do you need
different players and recorders but you need different displays as well
because the screen is redrawn at different intervals depending on the format
it is built for. The recording media, however, is the same, to a blank
tape, disc, or hard drive can be recorded anywhere in the world but will
need the same format gear in order to be watched.
James Nazarian
71 MGBGT V8
71 MGB Tourer
-----Original Message-----
From: owner-mgs@autox.team.net [mailto:owner-mgs@autox.team.net] On Behalf
Of Paul M.
Sent: Tuesday, May 18, 2004 10:52 PM
To: Rocky Frisco; mgs@autox.team.net
Subject: Re: British DVDs
--- Rocky Frisco <rock@rocky-frisco.com> wrote:
> Now, I'm confused. I was under the impression that
> the discs are either
> NTSC or PAL or whatever. They sure label them that
> way.
That's what I thought too. In fact, I had a bunch of
VHS tapes I bought i
=====
Paul Misencik - 1971 MGB - www.sopwithracing.com
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