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S-vhs????

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Anonymous
January 2, 2005 2:52:40 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

If my progressive scan DVD player puts out 450 lines of resolution and the
S-VHS jack takes 450 lines of resol;ution then why do I have it connected
with the red blue and green component jacks???

More about : vhs

Anonymous
January 2, 2005 2:52:41 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

i read it has better color seperation as well.


--
charper1
------------------------------------------------------------------------
This message was posted via http://www.satelliteguys.us by charper1
Anonymous
January 2, 2005 3:19:01 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

For one thing, because S-video output is interlaced (only 1/2 of the lines
are scanned every 1/60th of a second) and not progressive (where all of thee
lines are scanned every 1/60th of a second). Same number of lines, but
effectively only 30 complete frames per second. Your component connection
will allow progressively scanned output at 60 complete frames per second.

"Ski" <ski@nospamtoday.com> wrote in message
news:Xns95D1A146C6B4Meeenospamtodaycom@207.217.125.201...
> If my progressive scan DVD player puts out 450 lines of resolution and the
> S-VHS jack takes 450 lines of resol;ution then why do I have it connected
> with the red blue and green component jacks???
Related resources
Anonymous
January 2, 2005 3:19:02 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
> For one thing, because S-video output is interlaced (only 1/2 of the lines
> are scanned every 1/60th of a second) and not progressive (where all of thee
> lines are scanned every 1/60th of a second).

This is a bit off.

Interlaced video from a DVD player is 480/60i, which is 60 fields per
second. Each 1/60th of a second an entire field is painted on the
screen, which means that every 1/30th of a second an entire frame is
painted on the screen.

Progressive video from a DVD player is 480/30p, which is 30 frames per
second. Exactly like 480/60i, every 1/30th of a second an entire frame is
painted on the screen. The only difference is *how* they are painted.

Interlaced paints line 1, 3, 5, 7, etc., down to the bottom then line 2,
4, 6, 8, etc. Progressive paints 1, 2, 3, 4, etc., down to the bottom.

--
Jeff Rife | copy protection: n. A class of methods for
| preventing incompetent pirates from stealing
| software and legitimate customers from using it.
| Considered silly.
| -- Jargon File version 4.4.6
Anonymous
January 2, 2005 7:49:54 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

Actually, the progressively scanned output from a DVD is 480/60P.

A quick Google showed:the following at
http://www.panasonic.com/consumer_electronics/dvd_playe...

"The Benefits of Progressive Vs. Interlaced Scanning
Standard DVD-Video players use interlaced scanning to produce a picture.
Interlaced scanning combines two fields to generate a picture of 525 scan
lines (480 of which are displayed). Your television projects an interlaced
image by first scanning the 240 odd-numbered lines of one field (in 1/60th
of a second), followed by the 240 even-numbered lines of the other field (in
1/60th of a second). So, it takes two fields to build one frame of video.

Our progressive-scan DVD players have a progressive video processor, which
enables all 525 lines (480 of which are displayed) to be scanned at the
exact same time. A television with 480P component inputs can completely scan
the entire image in 1/60th of a second, so it only takes one field to build
one frame of video. The result is a smoother and sharper picture, with high
resolution and no motion artifacts."

Phil

"Jeff Rife" <wevsr@nabs.net> wrote in message
news:MPG.1c410cec1f01715d989a3d@news.nabs.net...
> Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
>> For one thing, because S-video output is interlaced (only 1/2 of the
>> lines
>> are scanned every 1/60th of a second) and not progressive (where all of
>> thee
>> lines are scanned every 1/60th of a second).
>
> This is a bit off.
>
> Interlaced video from a DVD player is 480/60i, which is 60 fields per
> second. Each 1/60th of a second an entire field is painted on the
> screen, which means that every 1/30th of a second an entire frame is
> painted on the screen.
>
> Progressive video from a DVD player is 480/30p, which is 30 frames per
> second. Exactly like 480/60i, every 1/30th of a second an entire frame is
> painted on the screen. The only difference is *how* they are painted.
>
> Interlaced paints line 1, 3, 5, 7, etc., down to the bottom then line 2,
> 4, 6, 8, etc. Progressive paints 1, 2, 3, 4, etc., down to the bottom.
>
> --
> Jeff Rife | copy protection: n. A class of methods for
> | preventing incompetent pirates from stealing
> | software and legitimate customers from using it.
> | Considered silly.
> | -- Jargon File version 4.4.6
Anonymous
January 2, 2005 7:49:55 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
> Actually, the progressively scanned output from a DVD is 480/60P.

No, it isn't, or at least it *shouldn't* be.

> A quick Google showed:the following at
> http://www.panasonic.com/consumer_electronics/dvd_playe...

The text on this page is wrong, but the diagram (which shows how 24p is
converted to 30p using 3:2 pulldown, then stored as 60i on the disc, and
then the reverse) is correct.

Although some progressive players *may* output 480/60p, they do so by
taking the 480/30p they get from de-interlacing and showing each frame
twice. This results in zero visual difference on screens with slow decay
phosphors (the majority of display devices).

--
Jeff Rife | "One minute we were spanking each other with
| meat, and the next minute it got weird."
|
| -- Joe Hackett, "Wings"
Anonymous
January 2, 2005 7:52:39 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

You might check here as well:

http://hometheater.about.com/od/beforeyoubuy/a/progress...

...."By progressively scanning the image onto a screen every 60th of a second
rather than "interlacing" alternate lines every 30th of a second, a
smoother, more detailed, image can be produced on the screen that is
perfectly suited for viewing fine details, such as text, and is also less
susceptible to interlace flicker."

"Jeff Rife" <wevsr@nabs.net> wrote in message
news:MPG.1c410cec1f01715d989a3d@news.nabs.net...
> Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
>> For one thing, because S-video output is interlaced (only 1/2 of the
>> lines
>> are scanned every 1/60th of a second) and not progressive (where all of
>> thee
>> lines are scanned every 1/60th of a second).
>
> This is a bit off.
>
> Interlaced video from a DVD player is 480/60i, which is 60 fields per
> second. Each 1/60th of a second an entire field is painted on the
> screen, which means that every 1/30th of a second an entire frame is
> painted on the screen.
>
> Progressive video from a DVD player is 480/30p, which is 30 frames per
> second. Exactly like 480/60i, every 1/30th of a second an entire frame is
> painted on the screen. The only difference is *how* they are painted.
>
> Interlaced paints line 1, 3, 5, 7, etc., down to the bottom then line 2,
> 4, 6, 8, etc. Progressive paints 1, 2, 3, 4, etc., down to the bottom.
>
> --
> Jeff Rife | copy protection: n. A class of methods for
> | preventing incompetent pirates from stealing
> | software and legitimate customers from using it.
> | Considered silly.
> | -- Jargon File version 4.4.6
Anonymous
January 2, 2005 7:52:40 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
> You might check here as well:
>
> http://hometheater.about.com/od/beforeyoubuy/a/progress...
>
> ..."By progressively scanning the image onto a screen every 60th of a second
> rather than "interlacing" alternate lines every 30th of a second, a
> smoother, more detailed, image can be produced on the screen that is
> perfectly suited for viewing fine details, such as text, and is also less
> susceptible to interlace flicker."

This is completely backwards.

Interlace draw alternate lines every 60th of a second, not every 30th, while
progressive draws each *frame* in the same scan...which is every 30th of
a second, not every 60th.

De-interlacing video that is (N)i results in (N/2)p output, at least as far
as quality is concerned. After that, you can repeat frames until you are
blue in the face, but it doesn't change the display.

--
Jeff Rife | "Eternity with nerds. It's the Pasadena Star
| Trek convention all over again."
|
| -- Nichelle Nichols, "Futurama"
Anonymous
January 3, 2005 12:26:40 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

Can you quote an actual source or reference that states that progressively
scanned DVD output is 480/30p?

"Jeff Rife" <wevsr@nabs.net> wrote in message
news:MPG.1c4210a961be25ba989a3f@news.nabs.net...
> Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
>> Actually, the progressively scanned output from a DVD is 480/60P.
>
> No, it isn't, or at least it *shouldn't* be.
>
>> A quick Google showed:the following at
>> http://www.panasonic.com/consumer_electronics/dvd_playe...
>
> The text on this page is wrong, but the diagram (which shows how 24p is
> converted to 30p using 3:2 pulldown, then stored as 60i on the disc, and
> then the reverse) is correct.
>
> Although some progressive players *may* output 480/60p, they do so by
> taking the 480/30p they get from de-interlacing and showing each frame
> twice. This results in zero visual difference on screens with slow decay
> phosphors (the majority of display devices).
>
> --
> Jeff Rife | "One minute we were spanking each other with
> | meat, and the next minute it got weird."
> |
> | -- Joe Hackett, "Wings"
Anonymous
January 3, 2005 12:39:59 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

I would agree that the statement "interlacing alternate lines every 30th of
a second" is incorrect, and probably wasn't a good source to quote.

This site has a much better explanation:
http://www.hometheaterhifi.com/volume_7_4/dvd-benchmark...


"Jeff Rife" <wevsr@nabs.net> wrote in message
news:MPG.1c42116ce673d98c989a40@news.nabs.net...
> Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
>> You might check here as well:
>>
>> http://hometheater.about.com/od/beforeyoubuy/a/progress...
>>
>> ..."By progressively scanning the image onto a screen every 60th of a
>> second
>> rather than "interlacing" alternate lines every 30th of a second, a
>> smoother, more detailed, image can be produced on the screen that is
>> perfectly suited for viewing fine details, such as text, and is also less
>> susceptible to interlace flicker."
>
> This is completely backwards.
>
> Interlace draw alternate lines every 60th of a second, not every 30th,
> while
> progressive draws each *frame* in the same scan...which is every 30th of
> a second, not every 60th.
>
> De-interlacing video that is (N)i results in (N/2)p output, at least as
> far
> as quality is concerned. After that, you can repeat frames until you are
> blue in the face, but it doesn't change the display.
>
> --
> Jeff Rife | "Eternity with nerds. It's the Pasadena Star
> | Trek convention all over again."
> |
> | -- Nichelle Nichols, "Futurama"
Anonymous
January 3, 2005 3:07:38 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
> Can you quote an actual source or reference that states that progressively
> scanned DVD output is 480/30p?

It doesn't matter if it is 480/240p...it still only contains 480/30p worth
of information.

Second, 480/30p is what comes out of all the de-interlacing algorithms.

A DVD player that outputs at 480/60p would be doing more work than is
necessary and possibly introducing further issues.

--
Jeff Rife | Al Gore: To my left, you'll recognize
| Gary Gygax, inventor of Dungeons &
| Dragons.
| Gary Gygax: Greetings it's a...
| [rolls dice]
| Gary Gygax: ...pleasure to meet you.
| -- "Futurama"
January 3, 2005 8:35:52 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

In article <MPG.1c42116ce673d98c989a40@news.nabs.net> Jeff Rife <wevsr@nabs.net> writes:
>Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
>> You might check here as well:
>>
>> http://hometheater.about.com/od/beforeyoubuy/a/progress...
>>
>> ..."By progressively scanning the image onto a screen every 60th of a second
>> rather than "interlacing" alternate lines every 30th of a second, a
>> smoother, more detailed, image can be produced on the screen that is
>> perfectly suited for viewing fine details, such as text, and is also less
>> susceptible to interlace flicker."
>
>This is completely backwards.
>
>Interlace draw alternate lines every 60th of a second, not every 30th, while
>progressive draws each *frame* in the same scan...which is every 30th of
>a second, not every 60th.
>
>De-interlacing video that is (N)i results in (N/2)p output, at least as far
>as quality is concerned. After that, you can repeat frames until you are
>blue in the face, but it doesn't change the display.


I disagree.

All I have seen matches the references that claim the progressive signal
is 60 per second. 30 frame per second progressive showing on a CRT would
have unacceptable flicker.


Alan
Anonymous
January 3, 2005 11:07:52 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

Ski wrote:
>If my progressive scan DVD player puts out 450 lines of
>resolution and the S-VHS jack takes 450 lines of resolution
>then why do I have it connected with the red blue and green
>component jacks???

The situation is more complicated than others suggest.
There are a lot of factors, so the best thing is actually
to test things out in three ways and see which looks best:

1. S-video connection
2. Component connection in 480i mode
3. Component connection in 480p mode

You should test these out using a widescreen movie DVD,
unless you dislike widescreen movies (in which case any
of your DVDs will suffice for testing).

S-Video actually has NO LIMIT to horizontal resolution.
For that matter, even composite has unlimited horizontal
resolution capability. However, this resolution capability
refers only to the luminance signal--the color signals have
lower resolution. However, DVDs already have a limited
color resolution, so the disadvantage of S-Video is
theoretically subtle. In practise, the electronics of the
TV and/or DVD player may make S-Video look significantly
worse than component.

In this thread, there has been a lot of misinformation
about what exactly is encoded on a DVD and what progressive
output "really" puts out. I don't have a link handy at the
moment, but if you do some digging around on the internet
you can find out the gruesome details. Those details
are not so important for you to know. What IS important for
you to know is that depending on the DVD player and the TV
set, SOMETIMES progressive mode will look better and
SOMETIMES interlaced mode will look better.

For example, assuming your TV is progressive mode capable,
DVD movie menus and subtitles should not flicker at all.
However, with some DVD players in progressive mode, the
menus and/or subtitles WILL flicker. So check this out.
Put your DVD player in progressive mode, and play a DVD;
turn on the subtitles. If you see the menus or subtitles
flickering, then you may want to avoid progressive mode.
Turn off progressive mode, and try out the DVD again.
The menus and subtitles should look rock solid.

The technical reason for the flickering is that the DVD player
is using a poor de-interlacing algorithm for the menus or
subtitles. Typically, this is because the DVD player
(correctly) reads a particular flag on the DVD disc which is
supposed to tell the player whether or not a frame is
interlaced or not (but this flag is very often encoded
INcorrectly on the disc). In contrast, the TV set has no
knowledge of this flag and instead uses a more complex
de-interlacing algorithm to figure out how to interpret
the video signal.

Theoretically, it's possible for a low end TV set to have
480p capability but to also lack a sophisticated de-interlacing
algorithm. In this case, the results of the above test
could be reversed--it looks flickery with interlaced output
but it looks rock solid with progressive output. In that
case, you'd want to use the progressive output option.

Basically, you just have to test out the various options and
see what looks best.

I personally have not run across a situation where the
S-Video output actually looks better than both component
output options, but I don't discount the possibility.

Isaac Kuo
Anonymous
January 3, 2005 3:31:42 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

"Jeff Rife" <wevsr@nabs.net> wrote in message
news:MPG.1c429d2273f07977989a41@news.nabs.net...
> Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
>> Can you quote an actual source or reference that states that
>> progressively
>> scanned DVD output is 480/30p?
>
>
> A DVD player that outputs at 480/60p would be doing more work than is
> necessary and possibly introducing further issues.

Standard 525 line NTSC (480i) video has a scan rate of 15.75 KHz

480p (same as progressive scan DVD) requires a monitor with a scan rate of
31.5 Khz (525x60)

So indeed the full picture is scanned 60 times per second.

1080i (1080 active lines 1125 total lines) requires a scan rate of 33.75
Khz (1125x30)

But 720p (720 active lines 750 total lines) requires a scan rate of 45 Khz
(750x60)

This also answers the question of why so many monitors that do 1080i do NOT
support 720p.
Anonymous
January 3, 2005 3:31:43 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

"Frank Provasek" <frank@frankcoins.com> wrote in message
news:o WaCd.5740$Cc.4079@newsread3.news.pas.earthlink.net...
> "Jeff Rife" <wevsr@nabs.net> wrote in message
> news:MPG.1c429d2273f07977989a41@news.nabs.net...
> > Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
> >> Can you quote an actual source or reference that states that
> >> progressively
> >> scanned DVD output is 480/30p?
> >
> >
> > A DVD player that outputs at 480/60p would be doing more work than is
> > necessary and possibly introducing further issues.
>
> Standard 525 line NTSC (480i) video has a scan rate of 15.75 KHz
>
> 480p (same as progressive scan DVD) requires a monitor with a scan rate of
> 31.5 Khz (525x60)
>
> So indeed the full picture is scanned 60 times per second.
>
> 1080i (1080 active lines 1125 total lines) requires a scan rate of 33.75
> Khz (1125x30)
>
> But 720p (720 active lines 750 total lines) requires a scan rate of 45
Khz
> (750x60)
>
> This also answers the question of why so many monitors that do 1080i do
NOT
> support 720p.

You are correct regarding the scan rates. Jeff's point, as I read it, was
that there is still no more information than was in the original 480i
source. Regardless of how many times you put it on the screen, it is the
same info.

I also don't understand the logic in your final statement. What kind of
monitors are you referring to?

Leonard
Anonymous
January 3, 2005 4:22:12 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

"Leonard Caillouet" <no@no.com> wrote in message
news:cbbCd.22411$jn.12075@lakeread06...
>
> "Frank Provasek" <frank@frankcoins.com> wrote in message
> news:o WaCd.5740$Cc.4079@newsread3.news.pas.earthlink.net...
>> "Jeff Rife" <wevsr@nabs.net> wrote in message
>> news:MPG.1c429d2273f07977989a41@news.nabs.net...
>> > Phil Ross (paross@pacbell.net) wrote in alt.tv.tech.hdtv:
>> >> Can you quote an actual source or reference that states that
>> >> progressively
>> >> scanned DVD output is 480/30p?
>> >
>> >
>> > A DVD player that outputs at 480/60p would be doing more work than is
>> > necessary and possibly introducing further issues.
>>
>> Standard 525 line NTSC (480i) video has a scan rate of 15.75 KHz
>>
>> 480p (same as progressive scan DVD) requires a monitor with a scan rate
>> of
>> 31.5 Khz (525x60)
>>
>> So indeed the full picture is scanned 60 times per second.
>>
>> 1080i (1080 active lines 1125 total lines) requires a scan rate of 33.75
>> Khz (1125x30)
>>
>> But 720p (720 active lines 750 total lines) requires a scan rate of 45
> Khz
>> (750x60)
>>
>> This also answers the question of why so many monitors that do 1080i do
> NOT
>> support 720p.
>
> You are correct regarding the scan rates. Jeff's point, as I read it, was
> that there is still no more information than was in the original 480i
> source. Regardless of how many times you put it on the screen, it is the
> same info.
>
> I also don't understand the logic in your final statement. What kind of
> monitors are you referring to?
>
> Leonard
>
Of course, there is no more information other than 30 complete pictures per
second.

Put since they are output at 60 frames per second, the monitor has to be
able to handle the
double work. This is of importance more to CRT based (RP or direct view)
monitors.
All of the scanning circuits must work at twice the speed of standard TV or
NON progressive
DVD.

And since 480p and 1080i have scan rates that are close, its easy to make a
monitor display both.

But for 720p, the monitor must be able to scan another 50% faster, so some
do not support it.
Anonymous
January 3, 2005 4:22:13 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

"Frank Provasek" <frank@frankcoins.com> wrote in message
news:8GbCd.16081$RH4.3590@newsread1.news.pas.earthlink.net...
> > You are correct regarding the scan rates. Jeff's point, as I read it,
was
> > that there is still no more information than was in the original 480i
> > source. Regardless of how many times you put it on the screen, it is
the
> > same info.
> >
> > I also don't understand the logic in your final statement. What kind of
> > monitors are you referring to?
> >
> > Leonard
> >
> Of course, there is no more information other than 30 complete pictures
per
> second.
>
> Put since they are output at 60 frames per second, the monitor has to be
> able to handle the
> double work. This is of importance more to CRT based (RP or direct view)
> monitors.
> All of the scanning circuits must work at twice the speed of standard TV
or
> NON progressive
> DVD.
>
> And since 480p and 1080i have scan rates that are close, its easy to make
a
> monitor display both.
>
> But for 720p, the monitor must be able to scan another 50% faster, so
some
> do not support it.

It is not that difficult to increase the scan rate another 50%. The reasons
that 720p is not supported as a native scan rate is a bit more than that.
Adding another scan rate requires additional signal selection and memory for
setup, as well as additional production like setup and service time. On
RPTV in particular this is a big issue, because all convergence setup needs
to be set for each scan rate. There have been multisync units since the
mid-80s that would do scan rates even higher, but they were rare and used
primarily for computer monitors. They were problematic because every
different scan configuration required new setup and more memory.

Leonard
!