1080I / 720P

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"drs_retired" <drs_retired@earthlink.net> wrote in message
news:5Y6tc.12403$be.2907@newsread2.news.pas.earthlink.net...
> What is the difference between 1080i and 720P ?
>
> Thank you
>
>

360G
 
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drs_retired wrote:
> What is the difference between 1080i and 720P ?
>
> Thank you
>
>


1080i: 1080 horizontal lines of resolution, with every other line
drawn each frame (interlaced)

720p: 720 horizontal lines of resolution, with all 720 drawn each
frame (progressive scan).
 
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In article <5Y6tc.12403$be.2907@newsread2.news.pas.earthlink.net>,
drs_retired@earthlink.net says...
> What is the difference between 1080i and 720P ?

Both are high definition formats. With 1080i, the "i" stands for
interlace. With 720p, the "p" stands for progressive scan.

They have roughly equivalent resolution, with 1080i having the edge in
horizontal resolution, 720p having the edge in vertical and color
resolution.

The progressive formats such as 720p are more amenable to the needs of
production, editing and special effects. A new format, 1080/24p, is
quickly becoming the new standard for high definition television
production. Many of us hope that it will become more widely used for
high definition transmission as well.
 
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drs_retired wrote:
> What is the difference between 1080i and 720P ?
>
> Thank you

1280 x720 progressive frames

1080 x 1920 interlaced fields

720p is generally better for displaying fast motion without artifacts
(sports is a good example and may be the reason ABC is at 720p and FOX
is going there).

1080i has more apparent resolution, especially with normal programming
(less motion). Despite the 1080i standard having 1920 lines of
horizontal resolution, my understanding is that most programming
probably comes closer to 1440.

In any case, most CRT-based sets display 1080i as it is easier for the
technology. 720p is pretty much the standard for fixed pixel displays.
Both are excellent and both will almost always convert the other HD
standard to the native format for the set. I say "almost" because there
are some CRT RPTV sets that do not accept 720p signals at all or
downconvert them to a lower SD resolution. You HD box will usually take
care of the conversion for you.

Some high-tech sets are in production that will display 1080p. I doubt
the industry will adopt this as a transmission standard as it will
consume more bandwidth. That's not to say that 1080i programming won't
look better on these sets.


--
David G.
 
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drs_retired wrote:
> What is the difference between 1080i and 720P ?
>
> Thank you

360 and a few letters.
 
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In article <MPG.1b1ecd4293216162989705@news.gwtc.net>,
Ron Malvern <rmlvrn@nospam.com> writes:
> In article <5Y6tc.12403$be.2907@newsread2.news.pas.earthlink.net>,
> drs_retired@earthlink.net says...
>> What is the difference between 1080i and 720P ?
>
> Both are high definition formats. With 1080i, the "i" stands for
> interlace. With 720p, the "p" stands for progressive scan.
>
> They have roughly equivalent resolution, with 1080i having the edge in
> horizontal resolution, 720p having the edge in vertical and color
> resolution.
>
Per the corrected 'Final Technical Report" dated Oct 31, 1995 in the ATSC
archives, the statement about 720p having the edge in vertical and
color resolution isn't quite accurate. For static information (which
is what most of us perceives as viewable detail), both 1080i
and 720p have approx the same vertical chroma and vertical luma
resolution. 1080i has higher horizontal and diagonal, chroma and
luma resolution than 720p.

For dynamic vertical resolution, the 720p does have the edge, but that
has seldom been denied. For almost all perceivable STATIC resolution
figures (including color), 1080i does provide more detail. Even
in the dynamic situation, 1080i has more horizontal detail (both
chroma and luma.)

John
 
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In article <c93c23$2fnm$1@news.iquest.net>, toor@iquest.net says...
> In article <MPG.1b1ecd4293216162989705@news.gwtc.net>,
> Ron Malvern <rmlvrn@nospam.com> writes:
> > They have roughly equivalent resolution, with 1080i having the edge in
> > horizontal resolution, 720p having the edge in vertical and color
> > resolution.
> >
> Per the corrected 'Final Technical Report" dated Oct 31, 1995 in the ATSC
> archives, the statement about 720p having the edge in vertical and
> color resolution isn't quite accurate. For static information (which
> is what most of us perceives as viewable detail), both 1080i
> and 720p have approx the same vertical chroma and vertical luma
> resolution. 1080i has higher horizontal and diagonal, chroma and
> luma resolution than 720p.

That's a blanket statement that simply isn't true. In the Final
Technical Report from the ATSC you mentioned above, look at table 2.3.

In vertical static chroma resolution, 720p rates 180, 1080i rates only
140.

In vertical dynamic luminance resolution, 720p rates 210, 1080i rates
200.

In horizontal dynamic chroma (color) resolution, 720 rates 170, 1080i
rates 135.

In vertical dynamic chroma (color) resolution, 720p rates 160, 1080i
rates only 100.

In diagonal dynamic chroma (color) resolution, 720p rates 183, 1080i
rates only 135.

> For dynamic vertical resolution, the 720p does have the edge, but that
> has seldom been denied. For almost all perceivable STATIC resolution
> figures (including color), 1080i does provide more detail.

But since we're talking about moving pictures here, dynamic resolution
with moving images will always be more important.
In addition, of course, the progressive formats take up less bandwidth,
meaning cleaner and more artifact-free transmission.
 
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On Wed, 26 May 2004 19:40:00 -0400, "David G."
<david_please_dont_email_me@i_hate_spam.com> wrote:

>Some high-tech sets are in production that will display 1080p. I doubt
>the industry will adopt this as a transmission standard as it will
>consume more bandwidth.

If you're talking 1080/60p, then the industry *can't* adopt this,
because IIRC it's not even part of the ATSC standard. Or, if it is in
the standard, it still isn't part of the broadcast standard, because
it won't fit into the current bandwidth alotted to TV channels.

If you mean 1080/24p, then the industry *should* adopt it (at least
for film-sourced material) because it reduces bandwidth.
 
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In article <MPG.1b1ef140da52bf36989706@news.gwtc.net>,
Ron Malvern <rmlvrn@nospam.com> writes:
> In article <c93c23$2fnm$1@news.iquest.net>, toor@iquest.net says...
>> In article <MPG.1b1ecd4293216162989705@news.gwtc.net>,
>> Ron Malvern <rmlvrn@nospam.com> writes:
>> > They have roughly equivalent resolution, with 1080i having the edge in
>> > horizontal resolution, 720p having the edge in vertical and color
>> > resolution.
>> >
>> Per the corrected 'Final Technical Report" dated Oct 31, 1995 in the ATSC
>> archives, the statement about 720p having the edge in vertical and
>> color resolution isn't quite accurate. For static information (which
>> is what most of us perceives as viewable detail), both 1080i
>> and 720p have approx the same vertical chroma and vertical luma
>> resolution. 1080i has higher horizontal and diagonal, chroma and
>> luma resolution than 720p.
>
> That's a blanket statement that simply isn't true. In the Final
> Technical Report from the ATSC you mentioned above, look at table 2.3.
>
> In vertical static chroma resolution, 720p rates 180, 1080i rates only
> 140.
>
That is a slight difference, when comparing the following:
720p diagonal is 230 vs. 1080i diagonal is 260.
Also, in the 'target spec' the difference between 1080i and 720p is
reversed. In essense, for static resolution, the few places
where 720p measures better in one case, it is the opposite in
the 'expected performance' case. So, the difference IN THIS
CASE is statistically NIL. (Refer to the implication of
measurement error in Note 1 in the table -- the difference
that you suggest is NIL.)

The difference that you claim to be 'significant' is well within
the implied 'measurement error' as mentioned in Note 1 in the
table.

If you want to compare the more important differences, refer to
the very significantly better horizontal and diagonal resolution
of 1080i. The vertical resolutions of 720p and 1080i are statistically
the same (except for the relatively more important static luma resolution,
where 1080i is outside of statistical equivalence.)

>
>> For dynamic vertical resolution, the 720p does have the edge, but that
>> has seldom been denied. For almost all perceivable STATIC resolution
>> figures (including color), 1080i does provide more detail.
>
> But since we're talking about moving pictures here, dynamic resolution
> with moving images will always be more important.
>
Nope -- most detail isn't moving, or MPEG wouldn't work!!! Take a look
at the typical TV show... Detail isn't typically moving!!! If your
claim is true, the MPEG wouldn't work. Most detail in video and
movies is unchanging...

All you have done is to demonstrate that 720p approaches statistical
parity in the statistically relatively UNCOMMON case of changing
details, otherwise 720p tends to have generally LESS detail.

John
 
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In article <c93jum$2i5b$1@news.iquest.net>, John Dyson toor@iquest.net
says...

> In article <MPG.1b1ef140da52bf36989706@news.gwtc.net>,
> > In vertical static chroma resolution, 720p rates 180, 1080i rates only
> > 140.

> That is a slight difference, when comparing the following:
> 720p diagonal is 230 vs. 1080i diagonal is 260.

In what? Chroma? Luma? You don't say. Be specific, John. For an
engineer, you are incredibly sloppy with details.


> Also, in the 'target spec' the difference between 1080i and 720p is
> reversed.

So?! The target spec doesn't matter. The test spec is what matters. Any
fool can say he want x and y performance from a given piece of equipment.
Doesn't mean he'll get it.

> In essense, for static resolution, the few places
> where 720p measures better in one case, it is the opposite in
> the 'expected performance' case. So, the difference IN THIS
> CASE is statistically NIL. (Refer to the implication of
> measurement error in Note 1 in the table -- the difference
> that you suggest is NIL.)

We're not talking statistics here, John. We're talking test results.
But if you want to make a big deal of that, then the entire ATSC Final
Technical Report is meaningless since almost all of the results are
within that margin of error. If that's the case, then why did you bring
up the Report?

> > But since we're talking about moving pictures here, dynamic resolution
> > with moving images will always be more important.

> Nope -- most detail isn't moving, or MPEG wouldn't work!!!

But the part of the image at the center of attention, faces, bodies, etc.
are moving all the time. And that's where resolution performace is
critically important.

> Take a look
> at the typical TV show... Detail isn't typically moving!!! If your
> claim is true, the MPEG wouldn't work. Most detail in video and
> movies is unchanging...

Gee John, you mean all that stuff on the screen in the movie theatres and
on television was just standing still all these years! It doesnt' really
matter if the oak tree in the background has more detail if the actors
eyes are fuzzy.

> All you have done is to demonstrate that 720p approaches statistical
> parity in the statistically relatively UNCOMMON case of changing
> details, otherwise 720p tends to have generally LESS detail.

John, the "motion" in motion pictures is quite common. And the "motion"
in motion pictures is the most important part of the image.
MPEG works because "much" of a given scene is standing still at any
given moment. How "much" varies from scene to scene and from movie to
movie. You're grasping at straws here.
 
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In article <q8eab0lhb4pqekdt9b06dbhlp10upucns1@4ax.com>,
Karyudo <karyudo_usenet@yahoo.com.remove.me> writes:
> On Wed, 26 May 2004 19:40:00 -0400, "David G."
> <david_please_dont_email_me@i_hate_spam.com> wrote:
>
>>Some high-tech sets are in production that will display 1080p. I doubt
>>the industry will adopt this as a transmission standard as it will
>>consume more bandwidth.
>
> If you're talking 1080/60p, then the industry *can't* adopt this,
> because IIRC it's not even part of the ATSC standard. Or, if it is in
> the standard, it still isn't part of the broadcast standard, because
> it won't fit into the current bandwidth alotted to TV channels.
>
> If you mean 1080/24p, then the industry *should* adopt it (at least
> for film-sourced material) because it reduces bandwidth.
>
If you read the ATSC spec, you'll notice that the 1080i30 signal can
be sent to take advantage of the redundancy of the 1080/24p original
source. So, you can get some advantage from the redundancy in the
24p originated material, yet transmit the signal in the 1080i30 format

John
 
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In article <c93k1c$2i5b$2@news.iquest.net>, toor@iquest.net says...

> If you read the ATSC spec, you'll notice that the 1080i30 signal can
> be sent to take advantage of the redundancy of the 1080/24p original
> source. So, you can get some advantage from the redundancy in the
> 24p originated material, yet transmit the signal in the 1080i30 format

First of all, 1080i is not referred to as 1080i30. It's 1080/60i.
Secondly it's commonly acknowedged that 1080/24p takes less bandwidth
than does 1080i because of the greater compression efficiency of
progressive scan.
 
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In article <MPG.1b1f0bca66244a57989707@news.gwtc.net>,
Ron Malvern <rmlvrn@nospam.com> writes:
> In article <c93jum$2i5b$1@news.iquest.net>, John Dyson toor@iquest.net
> says...
>
>> In article <MPG.1b1ef140da52bf36989706@news.gwtc.net>,
>> > In vertical static chroma resolution, 720p rates 180, 1080i rates only
>> > 140.
>
>> That is a slight difference, when comparing the following:
>> 720p diagonal is 230 vs. 1080i diagonal is 260.
>
> In what? Chroma? Luma? You don't say. Be specific, John. For an
> engineer, you are incredibly sloppy with details.
>
The context was obvious if you also look at the table. I assumed that
you could maintain context... Of course, maybe the large number
of discrete data items can cause confusion. (Alot like moving
objects on the screen :).) Perhaps all of the details within the
field of view might be confusing to you?

Remember also: if you maintain all detail in moving objects (allow temporal
aliasing), then movement doesn't even look natural. Film productions are
generally recorded with averaging over the entire sampling interval. There
is a natural motion smear to 'natural' perception. If you allow temporal
alasing, the movement tends to be less natural (and wierd strobing
effects become more troublesome.)

So, on filmed material, moving items tend to have less 'detail' because
of averaging over the exposure time. Some video cameras can set the
'exposure time' to be different than the frame rate -- but that is
more of a utility for special purposes (e.g. sports freeze frame or
flicker reduction or other purposes.)

>
>
>> Also, in the 'target spec' the difference between 1080i and 720p is
>> reversed.
>
> So?! The target spec doesn't matter.
>
Yes it does -- refer to the 'Note 1' that describes their concept
of measurement error (or equivalent.)

>
> The test spec is what matters.
>
And the differences were in the order of measurement error.

>
> Any
> fool can say he want x and y performance from a given piece of equipment.
>
You are being abusive. A fool with an agenda would ignore the concept of
measurement error...

>
> We're not talking statistics here, John. We're talking test results.
>
All tests have measurment error, Ron. The individuals who collected
the data apparently believed that there was error in their technique
or in their measurements.

>
> But if you want to make a big deal of that, then the entire ATSC Final
> Technical Report is meaningless
>
Reducing the argument to the absurd. Refer to the differences that
were deemed within measurement error. Note that the 'error' in this
context would also include measurement technique issues.

Remember: the significant differences that were outside of
reasonable 'measurement error' showed that 1080i provided more
detail.

>
>> > But since we're talking about moving pictures here, dynamic resolution
>> > with moving images will always be more important.
>
>> Nope -- most detail isn't moving, or MPEG wouldn't work!!!
>
> But the part of the image at the center of attention, faces, bodies, etc.
> are moving all the time.
>
However, the human visual system cannot deal with very much moving detail.
Also(side issue), moving image material that has been properly
exposed (to minimize temporal aliasing) will naturally have smear
due to movement.

Using your argument, you wouldn't care to keep a book still while
reading it -- because you could obviously track the vibrating book!!!
Not!!! (Hint, I have a movement disorder, and can attest to the
difficulty of tracking a moving page of text -- a prototypical
high detail image.)

Mostly, you'll easily see the gross details when something is moving.
You won't see all of the small little precise details (think about a
moving page of written text. Your eyes won't process the detail as well
as if it was still.)

>
>> Take a look
>> at the typical TV show... Detail isn't typically moving!!! If your
>> claim is true, the MPEG wouldn't work. Most detail in video and
>> movies is unchanging...
>
> Gee John, you mean all that stuff on the screen in the movie theatres and
> on television was just standing still all these years!
>
Most of the detail isn't moving, or MPEG-type interframe
compression wouldn't work. It appears that you are using semantics
to justify your incorrect argument...

Again, static detail rendition is more important for the perception
of sharpness. You CAN track moving objects, but your detail perception
is necessarily reduced (otherwise, you wouldn't need to keep books
still while reading them!!!)


John
 
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In article <c93onv$2jia$1@news.iquest.net>, toor@iquest.net says...
> In article <MPG.1b1f0bca66244a57989707@news.gwtc.net>,
> Ron Malvern <rmlvrn@nospam.com> writes:

> > In what? Chroma? Luma? You don't say. Be specific, John. For an
> > engineer, you are incredibly sloppy with details.

> The context was obvious if you also look at the table. I assumed that
> you could maintain context...

There are other people reading this who have no idea what data you're
referring to. Show a little consideration to them when making you're
arguments.

> Of course, maybe the large number
> of discrete data items can cause confusion.

Certainly on your part, yes.

> (Alot like moving
> objects on the screen :).) Perhaps all of the details within the
> field of view might be confusing to you?

Coming from a guy who can't tell the difference between still photos and
motion pictures, that's interesting.

> Remember also: if you maintain all detail in moving objects (allow
> temporal
> aliasing), then movement doesn't even look natural. Film productions
> are generally recorded with averaging over the entire sampling interval.
> There is a natural motion smear to 'natural' perception. If you allow
> temporal alasing, the movement tends to be less natural (and wierd
> strobing effects become more troublesome.)

John you're babbling again. You assume that your pseudo-technical BS
will snow the non-technical reader. Maybe it will.

> > We're not talking statistics here, John. We're talking test results.
> >
> All tests have measurment error, Ron. The individuals who collected
> the data apparently believed that there was error in their technique
> or in their measurements.

So why did you bring up the data? You used the test data to make your
point. But when I used data from the same source, suddenly it's suspect
because of margin of error. You can't have it both ways John.
You remind me of a politician who said a poll was showing him ahead of
his opponent. When a reporter pointed out that his opponent was leading
him 47 to 41, the politician said "yeah, but the margin of error of four
points puts me out in front of him"

> Most of the detail isn't moving, or MPEG-type interframe
> compression wouldn't work. It appears that you are using semantics
> to justify your incorrect argument...

And you are once again ignoring the fact the the reason people watch
motion pictures is because the pictures are.....John, pay
attention......moving!
 
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In article <MPG.1b1f13e39eea8545989709@news.gwtc.net>,
Ron Malvern <rmlvrn@nospam.com> writes:
> In article <c93k1c$2i5b$2@news.iquest.net>, toor@iquest.net says...
>
>> If you read the ATSC spec, you'll notice that the 1080i30 signal can
>> be sent to take advantage of the redundancy of the 1080/24p original
>> source. So, you can get some advantage from the redundancy in the
>> 24p originated material, yet transmit the signal in the 1080i30 format
>
> First of all, 1080i is not referred to as 1080i30. It's 1080/60i.
>
I have seen it both ways. 1080i30 would be 30 frames per second.
This would be equivalent to 720p60 as 60 frames per second. Likewise,
I have also seen it with the inconsistent approach like you suggest,
where sometimes it is 'frames per second' and sometimes it
is 'fields per second.' I prefer using the same units all of
the time, where the number after the i/p is 'frames per second.'

>
> Secondly it's commonly acknowedged that 1080/24p takes less bandwidth
> than does 1080i because of the greater compression efficiency of
> progressive scan.
>
The improvement between 1080p24 and 1080i30 isn't as great as one
might guess, because of the 'repeated' information that is sent
as 'repeats.' So, it doesn't really need to send 30 full frames
per second in the case of 1080i. The progressive thing is another
issue, but NOT THE ONLY ONE :).

Maybe you didn't realize that?

John
 
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In article <c93pfp$2jil$1@news.iquest.net>, toor@iquest.net says...
> In article <MPG.1b1f13e39eea8545989709@news.gwtc.net>,

> I have seen it both ways. 1080i30 would be 30 frames per second.
> This would be equivalent to 720p60 as 60 frames per second. Likewise,
> I have also seen it with the inconsistent approach like you suggest,
> where sometimes it is 'frames per second' and sometimes it
> is 'fields per second.' I prefer using the same units all of
> the time, where the number after the i/p is 'frames per second.'

The number doesn't refer to frames per second. It refers to Herz, or
cycles per second. And in this case, passes of the raster.
Secondly "frames" don't exist in an interlaced system. All you have
are "fields" that can't combine to make a frame, in spite of what you
were told in high school. The fields can't match to make a frame since
the fields are always exposed at different moments in time. This is why
taking still "frames" from interlaced material seldom produces good
results. This is also the main reason de-interlacers don't work well at
all.

> > Secondly it's commonly acknowedged that 1080/24p takes less bandwidth
> > than does 1080i because of the greater compression efficiency of
> > progressive scan.
> >
> The improvement between 1080p24 and 1080i30 isn't as great as one
> might guess, because of the 'repeated' information that is sent
> as 'repeats.' So, it doesn't really need to send 30 full frames
> per second in the case of 1080i. The progressive thing is another
> issue, but NOT THE ONLY ONE :).
> Maybe you didn't realize that?

Obviously you didn't realize that I was talking about compression
efficiencies produced by progressive scan. It is not "another" issue.
It is the main issue.
 
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On Wed, 26 May 2004 23:24:14 -0600, Ron Malvern <rmlvrn@nospam.com>
wrote:

>All you have
>are "fields" that can't combine to make a frame, in spite of what you
>were told in high school.

False for film-based material.

>The fields can't match to make a frame since
>the fields are always exposed at different moments in time.

False for film-based material.

>This is why
>taking still "frames" from interlaced material seldom produces good
>results.

False for film-based material.

All of these points are false when you're talking about material that
may be interlaced, but originated as film. Which is most TV dramas, a
number of sitcoms, and of course almost all movies.

John is correct; you are less so. You're right in saying that 24p is
more efficient, but John is not disputing that -- he's saying that the
improvement in efficiency over correctly-broadcast 30i is minimal,
which is true.
 
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Ron Malvern wrote:
> In article <c93pfp$2jil$1@news.iquest.net>, toor@iquest.net says...
>> In article <MPG.1b1f13e39eea8545989709@news.gwtc.net>,
>
>> I have seen it both ways. 1080i30 would be 30 frames per second.
>> This would be equivalent to 720p60 as 60 frames per second.
>> Likewise, I have also seen it with the inconsistent approach like
>> you suggest, where sometimes it is 'frames per second' and sometimes
>> it
>> is 'fields per second.' I prefer using the same units all of
>> the time, where the number after the i/p is 'frames per second.'
>
> The number doesn't refer to frames per second. It refers to Herz,
> or cycles per second. And in this case, passes of the raster.
> Secondly "frames" don't exist in an interlaced system. All you
> have are "fields" that can't combine to make a frame, in spite of
> what you were told in high school. The fields can't match to make a
> frame since the fields are always exposed at different moments in
> time. This is why taking still "frames" from interlaced material
> seldom produces good results. This is also the main reason
> de-interlacers don't work well at all.
>

Many deinterlacers work well in movie mode. It's video encoded
interlaced streams that are difficult to deinterlace. But companies such
as Faroujda with their DCDi have created some great deinterlacers for
video based material. I wonder what kind of processing is required
though to deinterlace a 1080i video stream.

--
David G.
 
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In article <6f2bb0p629dluk5ih2qkhkvmi2gu36cf10@4ax.com>,
karyudo_usenet@yahoo.com.remove.me says...
> On Wed, 26 May 2004 23:24:14 -0600, Ron Malvern <rmlvrn@nospam.com>
> wrote:
>
> >All you have
> >are "fields" that can't combine to make a frame, in spite of what you
> >were told in high school.
>
> False for film-based material.

Well, gee, let's all go back to shooting film. Since film is essentially
a progressive format, you're making my point.


> All of these points are false when you're talking about material that
> may be interlaced, but originated as film. Which is most TV dramas, a
> number of sitcoms, and of course almost all movies.

It doesn't say much for your interlaced system if you have to use an
essentially progressive scan camera-original such as film to make
your interlace work properly.
Film has been saving the ass of interlace for years.


> John is correct; you are less so. You're right in saying that 24p is
> more efficient, but John is not disputing that -- he's saying that the
> improvement in efficiency over correctly-broadcast 30i is minimal,
> which is true.

Progressive scan material compresses up to twenty percent more
efficiently, depending on the nature of the material. You can call that
minimal if you like. Nobody with any sense would. And by the way, 1080i
is 60i not 30i.