"Die, die, my darling!"

As both PAL and NTSC are basically dead systems (NTSC in the US, at least),
there is little point in discussing their differences. But as Mr. Alison
insists on displaying his ignorance in public, I'm going to, anyhow.

The first color TV system approved by the FCC was a field-sequential (or
frame-sequential -- I forget which) system proposed by CBS. It was developed
by Peter Goldmark, the same man given credit for the modern LP phonograph
record. (I say "given credit for", because there have been questions as to
whether he was the principal designer.)

The CBS system is a classic example of a design botched from the get-go. At
that time (not long after WWII), there was no practical way to display three
color images simultaneously with a single CRT. So Goldmark went with a
spinning color wheel, a system that had been tried 25 years earlier for
color motion pictures, and found wanting.

The problems with such a system are obvious, but I'll describe them. One
problem is that it requires three times as much film (or in the case of TV,
three times the bandwidth). Another is that moving objects show color
fringing.

Then there was the problem of the spinning color-filter disk. A 10" TV would
require one at least 2' in diameter. Imagine the disk needed for a 21" set!
(Not to mention the noise, and the possibility, however remote, of
decapitating the cat.)

These obvious (and lethal) deficiencies didn't deter Goldmark or CBS,
because they were in competition with RCA/NBC. The CBS argument was... Why
limit TV to B&W? Why not /start/ with a color system, and be done with it?
CBS pressed the FCC (as one writer pointed out, every sale of an RCA B&W TV
would be another nail in the coffin of the CBS color system), and in 1950
the CBS system was approved, despite the fact it was wholly incompatible
with the 480i system already in use. *

David Sarnoff ("the most-nasty name in electronics") was naturally upset.
RCA had to make CBS look bad, while completing development of their own
color system. Sarnoff gleefully pointed out that the CBS system was
"mechanical", and subject to all the limitations accruing thereto. Though
this was literally true, it overlooked the fact that one can have
all-electronic field-sequential color. But -- on the other hand -- CBS had
nothing other than a mechanical system to offer.

RCA was working on a "dot-sequential" system. Each line of the image was
divided into 300 (or so) pixels **, with red, green, and blue samples
alternating. This system worked fairly well -- it produced an acceptable
picture on B&W sets. But (for reasons I don't remember) color receivers had
problems displaying B&W images. As color receivers would (initially) be used
mostly for B&W viewing, this was not acceptable

The breakthrough came when engineers at Hazeltine and GE remembered Monseuir
Fourier, and recognized that sampling the colors was equivalent to a
"continuous" signal at the sampling frequency. They "slipped a note under
RCA's door" (so to speak), and NTSC/PAL came into existance. The color
information was transmitted on a subcarrier whose sidebands were interleaved
with the luminance sidebands, to minimize interaction. ***

"...complete with bad commercials that repeat all night, both in compatible
color and black and white." -- Stan Freberg

The brilliance of NTSC/PAL is that their signals produce as good (or better)
an image on B&W sets, and display excellent color on a color set -- without
making any existing equipment obsolete, and without requiring additional
bandwidth.

So... why is NTSC "better" than PAL? For one thing, it has "better" and
"more" color. Although the original NTSC proposal used red and blue color
signals of equal bandwidth, it was recognized that this didn't fit with the
way the eye actually sees color.

It turns out that for a 480-line system displayed on a 21" tube, the eye
sees full color (red/green/blue) only to about 0.5MHz. From 0.5MHz to
1.5MHz, the eye sees only those colors that can be matched with red-orange
and blue-green primaries. **** The system was therefore changed to the
red-orange/blue-green and yellow-purple primaries, the former of 1.5MHz
bandwidth, the latter of 0.5MHz bandwidth.

PAL uses equal-bandwidth (1.0 MHz) red and blue primaries. If an NTSC set
fully demodulates the 1.5MHz color signal (most limit it to 0.5MHz to make
the set cheaper), more of the original image's color detail will be
displayed (though this will be visible mostly in graphics).

Much has been made of PAL's phase alternation, especially its supposed
ability to eliminate the need for a tint [sic] control. (It should be hue
control.) When was the last time you adjusted the hue control on an NTSC
receiver? 30 years ago?

This issue is confused by two factors -- the differences between European
and American distribution systems, and their studio standards.

If the transmission network has constant group delay, the hue setting should
be set 'n forget, and never need to be changed. The American system had good
group-delay characteristics -- the European did not. So switching channels
could require twisting the hue knob. But that's not all there is to it.

Non-linear group delay changes the colors in a way that cannot be corrected
simply by adjusting the hue control. All the colors cannot be "correct" at
the same time. The advantage of PAL is that these color errors "flip" with
the phase, and are complementary -- the eye "averages" them to the correct
color.

So what's wrong with that? Well, the averaging also reduces saturation.
(Mixing an additive primary with its complement pushes it toward white.)
With severe group-phase error, the image shows bands of varying saturation.
(In NTSC, there are bands of varying hue.)

The other point of confusion is that, for many years, US broadcasters didn't
pay much attention to signal quality. Cameras weren't set up properly, and
burst phase wasn't properly monitored. So when you changed channels, you
sometimes had to change the hue setting. Broadcasters finally got their acts
together, and color quality has, for some time, been pretty consistent from
channel to channel.

In short, PAL's phase alternation is an advantage with transmission systems
having poor group-delay characteristics -- a problem that did not exist in
the US. In every other respect, it is inferior to NTSC.

All of this is true, to the best of my knowledge. Corrections and additions
are welcome.


* Some dishonest manufacturers sold B&W TVs with a "color converter" jack on
the back. It wouldn't have worked, because these sets didn't have the
required IF bandwidth (AFAIK).

** No, the term didn't exist at the time.

*** Some interaction is visible with objects having fine B&W detail. The set
"misinterprets" this detail as color information.

**** This is why two-primary color-movie systems (such as the original
Technicolor) could give acceptable -- though hardly great -- results.


--
"We already know the answers -- we just haven't asked the right
questions." -- Edwin Land

"William Sommer****** = Rabid Nut Case "

The belief that NTSC is a stupid design, and PAL corrects all the
bone-headed elements of NTSC, is untrue. The original NTSC proposal was
actually PAL (I have the copy of Electronics magazine to prove it), and
NTSC
is, overall, a less-compromised design than PAL.


** Wot a putrid pile of utterly absurd verbal sophistry.

The " original NTSC proposal " has got NOTHING to ****ING do with what
NTSC turned out to be in reality.

In * REALITY * the NTSC broadcast signal is massively compromised in
comparison to a PAL signal.

But on dark, smelly PLANET " Sommer******"

- any ****ing absurdity is held out to be true.



..... Phil

On Apr 1, 7:54*am, "Phil Allison" wrote:
"William Sommer****** = *Rabid *Nut Case *"



The belief that NTSC is a stupid design, and PAL corrects all the
bone-headed elements of NTSC, is untrue. The original NTSC proposal was
actually PAL (I have the copy of Electronics magazine to prove it), and
NTSC
is, overall, a less-compromised design than PAL.

** Wot a putrid pile of utterly absurd verbal sophistry.

The " original NTSC proposal " *has got NOTHING *to *****ING *do with what
NTSC turned out to be in reality.

In ** REALITY ** *the *NTSC broadcast signal is massively compromised in
comparison to a PAL signal.

But on dark, smelly *PLANET *" Sommer******"

*- any ****ing absurdity is held out to be true.

.... * Phil

PAL has plenty wrong with it and is 'massively compromised' the same
ways as NTSC. Editing in composite PAL is twice as crappy as NTSC
because of the 8 field PAL vs 4 field NTSC color frame sequences. Of
course nobody's done that kind of editing in many years since the
change to digital component in the '90s. Now with HD digital there
isn't any tape as the capture and editing is done in computers -
running (gasp) Windows XP. See Harris Nexio and Velocity.

G²

In * REALITY * the NTSC broadcast signal is massively compromised in
comparison to a PAL signal.


PAL has plenty wrong with it and is 'massively compromised' the same
ways as NTSC.

** More INSANE CRAPOLOGY !!!!!!!!!!


Editing in composite PAL .....


** More ****wit, OFF TOPIC CRAPOLOGY !!

See the words " broadcast signal " - ****head ???

Even know what it means ???



...... Phil

On Apr 1, 10:08*pm, "Phil Allison" wrote:


In * REALITY * the NTSC broadcast signal is massively compromised in
comparison to a PAL signal.

PAL has plenty wrong with it and is 'massively compromised' the same
ways as NTSC.

** *More *INSANE *CRAPOLOGY *!!!!!!!!!!

Editing in composite PAL .....

** More ****wit, *OFF *TOPIC *CRAPOLOGY *!!

See the words *" broadcast signal *" *- * ****head ???

Even know what it means *???

..... * Phil

They still do some composite D-2 editing at CBS network. Or don't they
count as broadcast?

G²

** More ****wit, OFF TOPIC CRAPOLOGY !!

See the words " broadcast signal " - ****head ???

Even know what it means ???


They still do some composite D-2 editing at CBS network. Or don't they
count as broadcast?


** Hey ****wit.

In relation to television transmission - where does one find the "
broadcast signal " ???

Don't strain you tiny brain thinking too hard.




...... Phil

In article
,
wrote:
PAL has plenty wrong with it and is 'massively compromised' the same
ways as NTSC. Editing in composite PAL is twice as crappy as NTSC
because of the 8 field PAL vs 4 field NTSC color frame sequences. Of
course nobody's done that kind of editing in many years since the
change to digital component in the '90s.

Company I worked for in the UK were using component recording (Panasonic
MII - high band like Beta SP) in the early '80s, and low band component
was around for quite some time before that. Although didn't meet UK
broadcast spec for most things, unlike high band. Within a couple of years
it was the main format with 1" relegated to archive use. Next change was
to DigiBeta.

--
*Give me ambiguity or give me something else.

Dave Plowman London SW
To e-mail, change noise into sound.

"William Sommer****** Mental Retard "

The belief that NTSC is a stupid design, and PAL corrects
all the bone-headed elements of NTSC, is untrue. The original
NTSC proposal was actually PAL (I have the copy of Electronics
magazine to prove it), and NTSC is, overall, a less-compromised
design than PAL.

Wot a putrid pile of utterly absurd verbal sophistry.


In * REALITY * the NTSC broadcast signal is massively
compromised in comparison to a PAL signal.


You don't know what the hell you're talking about. Put up or shut up.


** YOU have put up nothing but total ********.

Everything YOU ever posted is 100% PURE ****ING ********.

YOU are nothing but a stinking public menace and a VILE narcissistic prick.

**** Off and DIE !!!!!!!!!!

snip

This issue is confused by two factors -- the differences between European
and American distribution systems, and their studio standards.

If the transmission network has constant group delay, the hue setting
should
be set 'n forget, and never need to be changed. The American system had
good
group-delay characteristics -- the European did not. So switching channels
could require twisting the hue knob. But that's not all there is to it.

Non-linear group delay changes the colors in a way that cannot be
corrected
simply by adjusting the hue control. All the colors cannot be "correct" at
the same time. The advantage of PAL is that these color errors "flip" with
the phase, and are complementary -- the eye "averages" them to the correct
color.

I don't think that is actually true. It's been a lot of years since I
studied PAL decoding at college, but as far as I recall, the averaging is
done totally electronically, courtesy of the PAL delay line. This is a glass
block delay line of one scan-line period, so if you run a direct and a
delayed path side by side in the chrominance channel, and then sum the
outputs of both, you arrive at an electronically averaged result of two
sequential lines, with any phase errors balanced to zero. This has nil
effect on the overall colour saturation, as this is controlled by a) the ACC
circuit, and b) the user saturation control



So what's wrong with that? Well, the averaging also reduces saturation.
(Mixing an additive primary with its complement pushes it toward white.)
With severe group-phase error, the image shows bands of varying
saturation.
(In NTSC, there are bands of varying hue.)


snip

On 2/04/2010 12:45 PM, Arfa Daily wrote:
snip

This issue is confused by two factors -- the differences between European
and American distribution systems, and their studio standards.

If the transmission network has constant group delay, the hue setting
should
be set 'n forget, and never need to be changed. The American system had
good
group-delay characteristics -- the European did not. So switching channels
could require twisting the hue knob. But that's not all there is to it.

Non-linear group delay changes the colors in a way that cannot be
corrected
simply by adjusting the hue control. All the colors cannot be "correct" at
the same time. The advantage of PAL is that these color errors "flip" with
the phase, and are complementary -- the eye "averages" them to the correct
color.

I don't think that is actually true.

I think you'll find that was the intent. However, if the phase error is
too great, the eye averaging doesn't work so well, hence the
introduction of the delay line.

At which point you wonder why bother sending two colour signals in
quadrature if you're just going to average them with the next scan line
anyway. SECAM avoids that complexity by just going straight to the delay
line. I lived in Paris for 18 months. If there's a quality difference
between a SECAM and PAL picture, it was far from obvious.

Sylvia.

I think you'll find that was the intent. However, if the phase error is
too great, the eye averaging doesn't work so well, hence the
introduction of the delay line.

At which point you wonder why bother sending two colour signals in
quadrature if you're just going to average them with the next scan line
anyway.

But you don't have to average them. NTSC doesn't. And the delay line can be
used for comb filtering.


SECAM avoids that complexity by just going straight to the delay
line. I lived in Paris for 18 months. If there's a quality difference
between a SECAM and PAL picture, it was far from obvious.

The problem is, SECAM /requires/ the delay line because the system transmits
only the red or blue color-difference signal at any time. This is what I was
talking about -- it keeps the transmission side cheap, while making the user
pay more for their TV.

For most images, you won't see a difference. But in an image with strong
vertical color transitions, you'll see aliasing, especially when the image
moves vertically.

On 2/04/2010 9:50 PM, William Sommerwerck wrote:
I think you'll find that was the intent. However, if the phase error is
too great, the eye averaging doesn't work so well, hence the
introduction of the delay line.

At which point you wonder why bother sending two colour signals in
quadrature if you're just going to average them with the next scan line
anyway.

But you don't have to average them. NTSC doesn't. And the delay line can be
used for comb filtering.


SECAM avoids that complexity by just going straight to the delay
line. I lived in Paris for 18 months. If there's a quality difference
between a SECAM and PAL picture, it was far from obvious.

The problem is, SECAM /requires/ the delay line because the system transmits
only the red or blue color-difference signal at any time. This is what I was
talking about -- it keeps the transmission side cheap, while making the user
pay more for their TV.

For most images, you won't see a difference. But in an image with strong
vertical color transitions, you'll see aliasing, especially when the image
moves vertically.



If we were building an analogue colour TV transmission infrastructure
now, then maybe we'd go the NTSC route, since it eliminates the delay
line. But it's undoubtedly true that, for whatever reasons, in earlier
times, NTSC didn't perform that well, whereas those whose systems were
PAL or SECAM got good colour pictures from day one.

Sylvia.

"Stupider than Anyone Else Alive"


If we were building an analogue colour TV transmission infrastructure now,
then maybe we'd go the NTSC route, since it eliminates the delay line.

** Total insanity.


But it's undoubtedly true that, for whatever reasons, in earlier times,
NTSC didn't perform that well,


** The laws of nature have not changed since 1953

- you tenth witted, know nothing, bull****ting pommy bitch !!!



...... Phil

In article ,
Sylvia Else wrote:

On 2/04/2010 9:50 PM, William Sommerwerck wrote:
I think you'll find that was the intent. However, if the phase error is
too great, the eye averaging doesn't work so well, hence the
introduction of the delay line.

At which point you wonder why bother sending two colour signals in
quadrature if you're just going to average them with the next scan line
anyway.

But you don't have to average them. NTSC doesn't. And the delay line can be
used for comb filtering.


SECAM avoids that complexity by just going straight to the delay
line. I lived in Paris for 18 months. If there's a quality difference
between a SECAM and PAL picture, it was far from obvious.

The problem is, SECAM /requires/ the delay line because the system transmits
only the red or blue color-difference signal at any time. This is what I was
talking about -- it keeps the transmission side cheap, while making the user
pay more for their TV.

For most images, you won't see a difference. But in an image with strong
vertical color transitions, you'll see aliasing, especially when the image
moves vertically.



If we were building an analogue colour TV transmission infrastructure
now, then maybe we'd go the NTSC route, since it eliminates the delay
line. But it's undoubtedly true that, for whatever reasons, in earlier
times, NTSC didn't perform that well, whereas those whose systems were
PAL or SECAM got good colour pictures from day one.

And had high-brightness flicker for just as long...

Isaac

If we were building an analogue colour TV transmission
infrastructure now, then maybe we'd go the NTSC route,
since it eliminates the delay line.

PAL doesn't /require/ a delay line.


But it's undoubtedly true that, for whatever reasons, in earlier
times, NTSC didn't perform that well, whereas those whose
systems were PAL or SECAM got good colour pictures from
day one.

NTSC has always "performed well". Poor NTSC image quality was always due to
bad studio practice.

If the transmission network has constant group delay, the
hue setting should be set 'n forget, and never need to be
changed. The American system had good group-delay
characteristics -- the European did not. So switching channels
could require twisting the hue knob. But that's not all there is to it.

Non-linear group delay changes the colors in a way that
cannot be corrected simply by adjusting the hue control.
All the colors cannot be "correct" at the same time. The
advantage of PAL is that these color errors "flip" with
the phase, and are complementary -- the eye "averages"
them to the correct color.

I don't think that is actually true. It's been a lot of years since
I studied PAL decoding at college, but as far as I recall, the
averaging is done totally electronically, courtesy of the PAL
delay line. This is a glass block delay line of one scan-line
period, so if you run a direct and a delayed path side by side
in the chrominance channel, and then sum the outputs of both,
you arrive at an electronically averaged result of two sequential
lines, with any phase errors balanced to zero. This has nil effect
on the overall colour saturation, as this is controlled by a) the
ACC circuit, and b) the user saturation control.

The averaging can be done electronically, but there is also some visual
averaging.

I'm not sure you can remove the phase distortion without reducing the
saturation -- all the stuff I've read on PAL says otherwise -- but I won't
press the issue because I haven't thought it through carefully.

On 2/04/2010 12:13 AM, William Sommerwerck wrote:

If the transmission network has constant group delay, the hue setting should
be set 'n forget, and never need to be changed.

It's not clear to me why that wasn't the case anyway. Whatever phase
error was introduced to the colour signal by the transmission system
would also affect the colour burst. If the problem could be addressed by
means of a tint control with a setting that remained stable even over
the duration of a program, it rather seems to imply that a phase error
between the colour burst and the colour subcarrier was built into the
signal at the studio.

Sylvia.

"Sylvia Else" wrote in message
...
On 2/04/2010 12:13 AM, William Sommerwerck wrote:

If the transmission network has constant group delay, the
hue setting should
be set 'n forget, and never need to be changed.

It's not clear to me why that wasn't the case anyway.
Whatever phase error was introduced to the colour signal
by the transmission system would also affect the colour
burst. If the problem could be addressed by means of a
tint control with a setting that remained stable even over
the duration of a program, it rather seems to imply that a
phase error between the colour burst and the colour
subcarrier was built into the signal at the studio.

Sylvia

One big problem was differential phase and gain in the
transmission path. In this case both the amplitude and phase
of the color information was influenced by the total
amplitude of the signal including the luminance. Since the
burst was at IRE 0 and the average picture content was IRE
50 or so, differential phase shifted the color hue.

David

If the transmission network has constant group delay,
the hue setting should be set 'n forget, and never need
to be changed.

It's not clear to me why that wasn't the case anyway. Whatever
phase error was introduced to the colour signal by the transmission
system would also affect the colour burst. If the problem could be
addressed by means of a tint control with a setting that remained
stable even over the duration of a program, it rather seems to imply
that a phase error between the colour burst and the colour subcarrier
was built into the signal at the studio.

We're talking about non-linear group delay. This is not a simple phase error
in the burst, but a non-time-constant delay across the bandwidth of the
chroma signal. Any such non-linear delay will introduce varying color errors
that cannot be corrected with a single hue setting.

"William Sommer****** LYING TROLL "

NTSC has always "performed well".


** MASSIVE LIE .


Poor NTSC image quality was always due to
bad studio practice.


** Another MASSIVE LIE.

FOAD you stupid old AUTISTIC **** !!



..... Phil

On 4/04/2010 12:03 AM, William Sommerwerck wrote:
If the transmission network has constant group delay,
the hue setting should be set 'n forget, and never need
to be changed.

It's not clear to me why that wasn't the case anyway. Whatever
phase error was introduced to the colour signal by the transmission
system would also affect the colour burst. If the problem could be
addressed by means of a tint control with a setting that remained
stable even over the duration of a program, it rather seems to imply
that a phase error between the colour burst and the colour subcarrier
was built into the signal at the studio.

We're talking about non-linear group delay. This is not a simple phase error
in the burst, but a non-time-constant delay across the bandwidth of the
chroma signal. Any such non-linear delay will introduce varying color errors
that cannot be corrected with a single hue setting.



But, as you say, that kind of problem cannot be corrected with a single
hue setting, so no amount of fiddling with the tint control would have
produced an acceptable picture, even over a short timescale.

I understand that prior to the expiry of the Telefunken PAL patent, Sony
Trinitron sets for the PAL market actually threw away the chrominance
signal on alternate scan lines, thus landing themselves back in NTSC
territory. Those sets had a tint control, and I know from personal
experience that they produced a perfectly satisfactory result (I only
learnt the other day why they had a tint control).

So even if non-linear delay was a theoretical problem, it appears not to
have been one in practice. At least, not in the UK.

Sylvia.

In article ,
Sylvia Else wrote:
I understand that prior to the expiry of the Telefunken PAL patent, Sony
Trinitron sets for the PAL market actually threw away the chrominance
signal on alternate scan lines, thus landing themselves back in NTSC
territory. Those sets had a tint control, and I know from personal
experience that they produced a perfectly satisfactory result (I only
learnt the other day why they had a tint control).

Depends on what you mean by 'satisfacory'. Passable, maybe.

--
*Verbs HAS to agree with their subjects *

Dave Plowman London SW
To e-mail, change noise into sound.

I understand that prior to the expiry of the Telefunken PAL patent,
Sony Trinitron sets for the PAL market actually threw away the
chrominance signal on alternate scan lines, thus landing themselves
back in NTSC territory. Those sets had a tint control, and I know from
personal experience that they produced a perfectly satisfactory result
(I only learnt the other day why they had a tint control).

Depends on what you mean by "satisfactory". Passable, maybe.

When you discuss something at length, you become aware of those things you
thought you understood, but didn't. (Well, I do, anyway.)

I'd always read that one could construct a PAL receiver in such a way that
eliminated the need for a manual hue control. I never questioned this, but
now it makes little sense.

There are two reasons for having a manual hue control:

The user can adjust the color rendition to their personal (and usually
incorrect) taste. *
The user can correct for incorrect burst phase.

That seems to be "it". As we've seen, these errors can be corrected by
adjusting the hue control, whereas the other error -- differential phase
shift -- cannot be so-corrected, because the timing errors are not linear.

Here's where I get confused. The line-to-line polarity reversal ** causes
the differential phase errors to be equal and opposite, and thus cancel out
when added (at the cost of desaturation -- but that's another issue).

However... If the burst phase is wrong, then there is no cancellation of
errors, because there are no "errors" /in the signal itself/. (Right? (???))
Therefore, I don't see how line averaging can be used to eliminate the need
for a manual hue control.

If anyone knows of a reference with a non-tautological explanation, I'd
appreciate a pointer to it. Thanks.

* Left to their own devices, the average user generally sets the color for
greenish skin tones. I wonder if Vulcan viewers tended towards a pinkish
error.

** It's actually line-to-line+2, because the image is interlaced.

As both PAL and NTSC are basically dead systems
(NTSC in the US, at least)...

What about PAL and NTSC videos, DVD/Blu-ray?
When did they die?

I meant as broadcast systems. I have plenty of NTSC DVDs, and analog cable
signals are still NTSC.

Blu-ray is its own format (1080p/24 or 1080i/60).

Blu-ray is its own format (1080p/24 or 1080i/60).

Oh? So Blu-ray will play on a 50 or 60 Hz system
and the audio will be in sync?

Good question. I haven't looked to see whether a Blu-ray player can be set
to deliver an SD signal. I don't think it can.

Meat Plow wrote:

What about PAL and NTSC videos, DVD/BluRay? When did they die?

Technically video tapes are not NTSC or PAL. They have separate tracks
for luminance and chroma. The recorders all stripped them apart before
recording them and put them back together when playing them.

There is no technical reason not to build a video player with a digital
output, which digitzes the signals and presents them as an digital data
stream, with out actual NTSC nor PAL encoding. The field/frame rate would
be the same as the source material, but that's not the same thing.

The same with DVD's and BluRay. The data is encoded using MPEG compression,
which has separate information for luminance and chroma. It can be rebuilt
as red-green-blue pixels without ever going through NTSC or PAL.

As reg-green-blue cameras become more common, I expect that there will be
an eventual shift to rgb encoded data, but that's a long way off.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.

On Apr 1, 7:04*am, "Geoffrey S. Mendelson"
wrote:
Meat Plow wrote:
What about PAL and NTSC videos, DVD/BluRay? When did they die?

Technically video tapes are not NTSC or PAL. They have separate tracks
for luminance and chroma. The recorders all stripped them apart before
recording them and put them back together when playing them.

There is no technical reason not to build a video player *with a digital
output, which digitzes the signals and presents them as an digital data
stream, with out actual NTSC nor PAL encoding. The field/frame rate would
be the same as the source material, but that's not the same thing.

The same with DVD's and BluRay. The data is encoded using MPEG compression,
which has separate information for luminance and chroma. It can be rebuilt
as red-green-blue pixels without ever going through NTSC or PAL.

As reg-green-blue cameras become more common, I expect that there will be
an eventual shift to rgb encoded data, but that's a long way off.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel *N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.