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Is there a Analog to Digital Converter ?

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Anonymous
June 25, 2004 2:19:41 PM

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

I'm setting here thinking which is bad !

If the Dish and Cable can do it, maybe there is a Device that I could own in
my home to convert to Digital ?
June 25, 2004 11:36:54 PM

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

In article <dL6dnW2GVZLt3EHd4p2dnA@giganews.com> "Joe H" <JoeT@mailpuppy.com> writes:
> I'm setting here thinking which is bad !
>
>If the Dish and Cable can do it, maybe there is a Device that I could own in
>my home to convert to Digital ?

Yes, there is, but why? Once the signal is at your home, one would expect
you to want to display it.

The advantage of digital is to be able to transmit it efficiently over
the air (or cable or satellite) with high and consistent quality. Once it
gets to your home, that function is essentially complete.

Obviously, there are converters. The cable companies and satellite
companies buy them. You could buy one too, if you had enough available
money. The point, though, is: why?


Alan
Anonymous
June 25, 2004 11:36:55 PM

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

Did I put that right !

Cable comes into my house as Analog, then there box converts it to Digital.

The dish gets a Analog and then converts to Digital, but a much better
picture then Cable.

So, what I'm saying is: Is there a box that when the Digital comes in by
cable, I, I say I, can convert it toDigital ?

"Alan" <nospam@w6yx.stanford.edu> wrote in message
news:cbhusm$4ql$1@news.Stanford.EDU...
> In article <dL6dnW2GVZLt3EHd4p2dnA@giganews.com> "Joe H"
<JoeT@mailpuppy.com> writes:
> > I'm setting here thinking which is bad !
> >
> >If the Dish and Cable can do it, maybe there is a Device that I could own
in
> >my home to convert to Digital ?
>
> Yes, there is, but why? Once the signal is at your home, one would
expect
> you to want to display it.
>
> The advantage of digital is to be able to transmit it efficiently over
> the air (or cable or satellite) with high and consistent quality. Once it
> gets to your home, that function is essentially complete.
>
> Obviously, there are converters. The cable companies and satellite
> companies buy them. You could buy one too, if you had enough available
> money. The point, though, is: why?
>
>
> Alan
Related resources
Anonymous
June 25, 2004 11:36:56 PM

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

On Fri, 25 Jun 2004 15:31:05 -0500, in article
<vNWdnUZUD5bxF0HdRVn-hQ@giganews.com>, "Joe H" <JoeT@mailpuppy.com>
wrote:

>Did I put that right !
>
>Cable comes into my house as Analog, then there box converts it to Digital.
>
>The dish gets a Analog and then converts to Digital, but a much better
>picture then Cable.

You've got this backwards. The digital cable signals are coming in as
digital; the box converts it to analog so your TV can display it. Same
with satellite.

>So, what I'm saying is: Is there a box that when the Digital comes in by
>cable, I, I say I, can convert it toDigital ?

Huh?

There are analog to digital converters, combined with MPEG encoders, in
devices like DVRs (e.g. Tivo) and DVD-R decks. They allow you to
convert analog video to digital for storage. What are you trying to do?
--
Stephen Tu
stephtu@surfbest.net
Anonymous
June 25, 2004 11:36:56 PM

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

In article <vNWdnUZUD5bxF0HdRVn-hQ@giganews.com>, JoeT@mailpuppy.com
says...
> Did I put that right !
>
> Cable comes into my house as Analog, then there box converts it to Digital.
>
> The dish gets a Analog and then converts to Digital, but a much better
> picture then Cable.

A simple way to answer your question is: by the time the signal
arrives at your house, in whatever form, it has already been
degraded, and any conversions you do to it at that point will at best
maintain the quality, not improve it.

/Chris, AA6SQ
Anonymous
June 26, 2004 8:31:06 AM

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

"Chris Thomas" wrote:
> A simple way to answer your question is: by the time the signal
> arrives at your house, in whatever form, it has already been
> degraded, and any conversions you do to it at that point will at best
> maintain the quality, not improve it.

Not really true...if the signal being delivered is digital either by
satellite or cable, then the 1's and 0's that make up the signal are still
the same quality 1's and 0's when they arrive at the house. The degradation
takes place if there's a set box that converts it to analog. In the case of
HDTV's, if you're using a DVI or HDMI enabled box to your TV than the signal
remains digital all the way to the display. If the display is LCD, Plasma,
or DLP then the signal never really lost quality. If the HDTV is CRT than
you do lose some quality as the signal is converted to analog inside the
HDTV.

borromini
Anonymous
June 26, 2004 10:40:51 AM

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

"borromini" <asdf@asdf.com> wrote in message news:<e_6Dc.78252$1L6.70360@newssvr29.news.prodigy.com>...
> "Chris Thomas" wrote:
> > A simple way to answer your question is: by the time the signal
> > arrives at your house, in whatever form, it has already been
> > degraded, and any conversions you do to it at that point will at best
> > maintain the quality, not improve it.
>
> Not really true...if the signal being delivered is digital either by
> satellite or cable, then the 1's and 0's that make up the signal are still
> the same quality 1's and 0's when they arrive at the house. The degradation
> takes place if there's a set box that converts it to analog.


The previous poster's point was that the biggest video quality issue
is how much compression is done on the analog source when it is
converted to digital for transmission. Some cable companies compress
more than others to enable more channels within the bandwidth of their
system. This is something the end user has no control over.



In the case of
> HDTV's, if you're using a DVI or HDMI enabled box to your TV than the signal
> remains digital all the way to the display. If the display is LCD, Plasma,
> or DLP then the signal never really lost quality. If the HDTV is CRT than
> you do lose some quality as the signal is converted to analog inside the
> HDTV.
>
> borromini
Anonymous
June 26, 2004 11:09:39 AM

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

It seems as if people are a little overly attached to the idea that the
signal is digital all the way to the display when using dvi or hdmi. Under
perfect circumstances this is probably true. There is a slight advantage
under perfect conditions. The reality under normal conditions though is that
there is none. The web avs and hdtv forums have talked about this.
Generally if the equipment is adjusted properly (mainly the display) there
will be no difference. However some people may perceive a difference
because their contrast, brightness, color is misadjusted in a specific mode
and thus does not look as good.

While the siganl being digital all the way seems like the best idea, there
are flaws in this whole idea. The signal is actually mpeg2, this
compression introduces flaws in the siganl. That is origial video comes
from a sensor which is directly focused on a live scene or film. This
process is inherent analog to digital.. The compression of the mpeg2
introduces loss of detail and color accuracy. This process creates far more
problems than say the digial to analog conversion for display on a CRT

The only place I have seen the advantage is on computers whch of course is
why DVI was invented. Computers generate the raw image in a frame buffer.
the is no compression artifacts since the frame buffer is directly converted
to dvi information and then to an image on say an lcd. Under these
circumstances there is a noticeable difference in quality between lcd and
analog crt. However if you display a dvd on a computer screen you will see
no difference between a crt and a lcd (assuming both are adjsuted properly).
Here again it is because the mpeg2 compromises far outweigh any other
issues.

Richard R.



"borromini" <asdf@asdf.com> wrote in message
news:e_6Dc.78252$1L6.70360@newssvr29.news.prodigy.com...
> "Chris Thomas" wrote:
> > A simple way to answer your question is: by the time the signal
> > arrives at your house, in whatever form, it has already been
> > degraded, and any conversions you do to it at that point will at best
> > maintain the quality, not improve it.
>
> Not really true...if the signal being delivered is digital either by
> satellite or cable, then the 1's and 0's that make up the signal are still
> the same quality 1's and 0's when they arrive at the house. The
degradation
> takes place if there's a set box that converts it to analog. In the case
of
> HDTV's, if you're using a DVI or HDMI enabled box to your TV than the
signal
> remains digital all the way to the display. If the display is LCD,
Plasma,
> or DLP then the signal never really lost quality. If the HDTV is CRT than
> you do lose some quality as the signal is converted to analog inside the
> HDTV.
>
> borromini
>
>
Anonymous
June 26, 2004 6:03:51 PM

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

borromini wrote:

In the case of
> HDTV's, if you're using a DVI or HDMI enabled box to your TV than the signal
> remains digital all the way to the display. If the display is LCD, Plasma,
> or DLP then the signal never really lost quality. If the HDTV is CRT than
> you do lose some quality as the signal is converted to analog inside the
> HDTV.

The D/A conversion is required regardless of the display type, if the
input is digital. Even DLP displays must convert from digital to analog.
Think about it; digital in and your eyeballs see an output analog
picture. Somewhere between the input and the display output a D/A
conversion must have occurred. In the case of DLP, the micro mirrors are
pulse width modulated to provide the gray scale range of brightness.
Conversion anomalies still occur regardless if the D/A conversion is a
traditional type D/A a PWM type D/A conversion.
Anonymous
June 27, 2004 2:15:47 PM

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

I was talking to a person that was a something like high up and truthfull, I
had thought.

I had the Dish (for 24 hours) and they convert to Digital and you can really
see the difference, (but WE could see the shapness was not there, it was
like a little Blurry) but I was told by Cable that that they use Digital to
be able to give you more channels, BUT ! he said the picture itself is
analog, and on a big Tv it really shows. Cable guy said (and the Dish Guy),
that all the regular channels are Analog or regular whatever, you must
convert them, and the Dish does, but they recieve them as Regular (Analog
?), in the Dish there was no Movement, snow lines or whatever, (they do not
carry ABC, NBC, CBS in HD though.

1 - I'm not trying to get something for nothing, just trying to get a
sharper picture on a 50 inch screen.
2 - Even on my 20 inch crt in the Kitchen you can see the Noise and things
and that's why I asked.

I am a Electronic Nut, with my own computers, in fact almost a
Perfectionish, so don't get up tight on me, I'm up there in age,(and things
move fast in electronics) ,and if improvements can be made without all the
Big $$, I want to do it.
OT: In fact my Computer is a AMD CPU running at 1.6, by fall I will
assemble a 3.2 I hope, if I'm still around.

"Richard R"
[SNIP]
Anonymous
June 27, 2004 7:59:33 PM

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

The problem is the quality of your source. NTSC is subject to all sorts of
noise which will be painfully evident when converted to HD even with some
good processing scalers available. My HDTV upconverts, aliases, captures
3:2 pulldown etc. While this minimizes the problem you cannot escape the
source quality issue. Even if the video is digital all the way, the flaws
are always there and especially evident when you have a big picture and HD
scaling. My point is that good scaler processing, dvi or component cannot
fix a mediocre source. In fact with a poor source quality you are better
off with a regular SD analog video TV. HD and SD sources look good on my
SDTV but typically only okay on my HDTV. When a good HD source comes on
though the results are impressive on my HDTV. Unfortunately most HD source
are not that good.

DVI also intrduces some problems. If you change channels the STB will have
to re-sync DVI as the resolutions shift around. If you have a low res
source the typical DVI input will not re-scale. Note that component video
often allows you to set say 1080i permanently and will automatically stay in
sync between channels.

While DVI sounds like the ultimate hype solution the reality is that it has
limitations just like anything else. The real solutions would have been
firewire. But nobody seems to support it and what support is available is
not that good. Why firewire ? Because the video and audio could be
maintained in native form until it gets to the actual rendering unit (video
display or audio amplifier).

Richard R.

"Joe H" <JoeT@mailpuppy.com> wrote in message
news:gKSdnbsCQtgffkPdRVn-uA@giganews.com...
> I was talking to a person that was a something like high up and truthfull,
I
> had thought.
>
> I had the Dish (for 24 hours) and they convert to Digital and you can
really
> see the difference, (but WE could see the shapness was not there, it was
> like a little Blurry) but I was told by Cable that that they use Digital
to
> be able to give you more channels, BUT ! he said the picture itself is
> analog, and on a big Tv it really shows. Cable guy said (and the Dish
Guy),
> that all the regular channels are Analog or regular whatever, you must
> convert them, and the Dish does, but they recieve them as Regular (Analog
> ?), in the Dish there was no Movement, snow lines or whatever, (they do
not
> carry ABC, NBC, CBS in HD though.
Anonymous
June 27, 2004 10:21:32 PM

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

Thanks Richard, Once something is not good, rarely can you make it better.

As was said about OTA, Use a antenna with a amp, well I got what I thought
would work best, and no amp. If you can't pick it up clear to start with,
your only going to amplify the noise with the signal.

I'm down in the valley, and have to go through some trees about 30 feet
away, but I got a very good signal on most. Some are 3/4 strenght, but none
are under half.

"Richard R" <jwerir@wideopenwest.com> wrote in message
news:kcmdnYfPwLWj3kLd4p2dnA@wideopenwest.com...
> The problem is the quality of your source. NTSC is subject to all sorts
of
> noise which will be painfully evident when converted to HD even with some
> good processing scalers available. My HDTV upconverts, aliases, captures
> 3:2 pulldown etc. While this minimizes the problem you cannot escape the
> source quality issue. Even if the video is digital all the way, the flaws
> are always there and especially evident when you have a big picture and HD
> scaling. My point is that good scaler processing, dvi or component cannot
> fix a mediocre source. In fact with a poor source quality you are better
> off with a regular SD analog video TV. HD and SD sources look good on my
> SDTV but typically only okay on my HDTV. When a good HD source comes on
> though the results are impressive on my HDTV. Unfortunately most HD
source
> are not that good.
>
> DVI also intrduces some problems. If you change channels the STB will
have
> to re-sync DVI as the resolutions shift around. If you have a low res
> source the typical DVI input will not re-scale. Note that component video
> often allows you to set say 1080i permanently and will automatically stay
in
> sync between channels.
>
> While DVI sounds like the ultimate hype solution the reality is that it
has
> limitations just like anything else. The real solutions would have been
> firewire. But nobody seems to support it and what support is available is
> not that good. Why firewire ? Because the video and audio could be
> maintained in native form until it gets to the actual rendering unit
(video
> display or audio amplifier).
>
> Richard R.
>
> "Joe H" <JoeT@mailpuppy.com> wrote in message
> news:gKSdnbsCQtgffkPdRVn-uA@giganews.com...
> > I was talking to a person that was a something like high up and
truthfull,
> I
> > had thought.
> >
> > I had the Dish (for 24 hours) and they convert to Digital and you can
> really
> > see the difference, (but WE could see the shapness was not there, it was
> > like a little Blurry) but I was told by Cable that that they use Digital
> to
> > be able to give you more channels, BUT ! he said the picture itself is
> > analog, and on a big Tv it really shows. Cable guy said (and the Dish
> Guy),
> > that all the regular channels are Analog or regular whatever, you must
> > convert them, and the Dish does, but they recieve them as Regular
(Analog
> > ?), in the Dish there was no Movement, snow lines or whatever, (they do
> not
> > carry ABC, NBC, CBS in HD though.
>
>
!