Why such a mess with native resolutions?

I've been watching HDTV on my SDTV set for a couple months now,
and I'm close to jumping to an HDTV (or maybe EDTV, if the budget
so requires) set.

But I'm so confused when I see the specs, specifically the native
resolution (which I assume is the size of the physical grid of
pixels -- i.e., the *actual* amount of pixels horizontally and
vertically).

My confusion is: if the standard resolutions are 480, 720, and
1080, then why aren't the panel resolutions restricted to sizes
that match *exactly* those, at 16:9 ratio?? The way I see it,
there should *only* be panels with resolutions 854 x 480,
1280 x 720, and 1920 x 1080.

Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).

The second part of my question is: what do those TV sets do
with the signal? "Resample" it to fit the panel's resolution?
Is there not a noticeable deterioration in the quality of the
signal?

In particular, what do TV sets with 1360 x 768 do? Do they
"crop" in the panel's area and use the middle 1280 x 720??
Or do they stretch/resample the signal to expand it to take
the full panel's area?? Seems gratuitous to me -- why wouldn't
they simply make the panel 1280 x 720??

BTW, don't be afraid to get technical -- I'm an Electronics
Engineer, and have done some work on Image Processing, so feel
free to throw technical/mathematical arguments if needed.

Thanks,

Carlos
--

My confusion is: if the standard resolutions are 480, 720, and
1080, then why aren't the panel resolutions restricted to sizes
that match *exactly* those, at 16:9 ratio?? The way I see it,
there should *only* be panels with resolutions 854 x 480,
1280 x 720, and 1920 x 1080.

Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).

Hooking up the Xbox? Or your PC? Especially with 1024 x 768

Lots of things you can do with your HDTV besides watch TV/dvd's

"Carlos Moreno" wrote in message
...


Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).


I bet the 1024 x 720 and the 1024 x 1024 were plasma sets. They don't seem
to be able to make the plasma pixels small enough to get 1280 horizontally
on a screen smaller than 50 inches. This also means that in a 16 : 9 format
you don't get square pixels.


The second part of my question is: what do those TV sets do
with the signal? "Resample" it to fit the panel's resolution?
Is there not a noticeable deterioration in the quality of the
signal?

In particular, what do TV sets with 1360 x 768 do? Do they
"crop" in the panel's area and use the middle 1280 x 720??
Or do they stretch/resample the signal to expand it to take
the full panel's area?? Seems gratuitous to me -- why wouldn't
they simply make the panel 1280 x 720??

Other than non TV applications, the only thing I can think of is that a 1920
x 1080 picture might look better on a 1360 x 768 than a 1280 x 720. Also,
768 is a standard PC vertical resolution. No, they don't crop/stretch; it's
resapled.

Tam


BTW, don't be afraid to get technical -- I'm an Electronics
Engineer, and have done some work on Image Processing, so feel
free to throw technical/mathematical arguments if needed.

Thanks,

Carlos
--

Leadfoot wrote:

My confusion is: if the standard resolutions are 480, 720, and
1080, then why aren't the panel resolutions restricted to sizes
that match *exactly* those, at 16:9 ratio?? The way I see it,
there should *only* be panels with resolutions 854 x 480,
1280 x 720, and 1920 x 1080.

Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).

Hooking up the Xbox? Or your PC? Especially with 1024 x 768

But still, the physical aspect ratio of the panel is 16:9. If
you plug your PC (at a resolution of 1024x768), then the image
would look horizontally stretched -- unless they resample it,
which would defeat the argument of using 1024 x 768 because
that's a typical resolution of PC or game consoles. Sounds
quite strange to me.

OTOH, there's plenty of PC monitors now that are 16:9, with
native resolutions that do respect that ratio -- so, you can
typically (with virtually any video card recent enough) configure
the video output at 1280 x 720, or 1360 x 768, etc. etc.

The PC monitors that are 4:3 have a native resolution consistent
with 4:3, and those who are 16:9 similarly. Why don't TVs do
the same thing and respect the actual/physical geometry of the
panel?

Lots of things you can do with your HDTV besides watch TV/dvd's

Agreed. But being 16:9, and being called Plasma TV, sounds to
me like the main intended application is to watch HDTV. Plus,
regardless, the argument about respecting the physical aspect
ratio of the panel seems valid anyway, no?

Carlos
--

"Carlos Moreno" wrote in message
...
My confusion is: if the standard resolutions are 480, 720, and
1080, then why aren't the panel resolutions restricted to sizes
that match *exactly* those, at 16:9 ratio?? The way I see it,
there should *only* be panels with resolutions 854 x 480,
1280 x 720, and 1920 x 1080.

Yes.


Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).

In the early days, it was because the scalers were mostly off the shelf
computer scalers and drivers designed for comptuers, which were designed for
circuit effeciency and CRT needs.

Today, it's because there's only a few factories in the world that produce
the huge sheets of glass and then they are cut up in various combinations to
match demand at the time.

It's alot cheaper that way.

The 1024x1024 screens were ALiS (Sony & LG) not Panasonic. They're actually
interlaced. Only 512 lines can be accessed each frame.


The second part of my question is: what do those TV sets do
with the signal? "Resample" it to fit the panel's resolution?
Is there not a noticeable deterioration in the quality of the
signal?

Yes and yes.


In particular, what do TV sets with 1360 x 768 do? Do they
"crop" in the panel's area and use the middle 1280 x 720??
Or do they stretch/resample the signal to expand it to take
the full panel's area?? Seems gratuitous to me -- why wouldn't
they simply make the panel 1280 x 720??

BTW, don't be afraid to get technical -- I'm an Electronics
Engineer, and have done some work on Image Processing, so feel
free to throw technical/mathematical arguments if needed.

1366

They don't just crop (well a bit of the edge on most analog systems contains
non-picture data and is usually cropped).

The scaler varies greatly by brand and model. From simple decimation (just
dropping lines) on generic little LCDs to a variation on the line based 3D
comb filter on name brand TVs to weighted resampling of an adaptively
deinterlaced buffer on a computer or stand alone image processor.
Processing artifacts annoy people to different degrees, so it's best to look
at stuff in person yourself before you buy. A computer can easily do it
right but companies that expect to sell 1M TVs typically want to do it as
cheap as possible, even on $3K TVs.

If you can't find something you're really happy with and can easily afford,
then just wait. The prices are still falling and several new technologies
on the way.

If it's just you, there are several 23/24" 1920x1200p computer monitors for
around $700 or $800 that can be used to watch TV. 24" may sound small
compared to 50" TVs but when you're sitting right in front of it, it fills
up your field of view. There are also several 20/22" 1680x1050 LCDs, around
$380 to $450. Find one with external video inputs like the Dells or get a
TV tuner card for your PC or Mac. That way you have a nice monitor and
HDTV. BTW, those montiors are 16:10 aspect ratio so the regular 16:9 HDTV
is shown in letterbox format like DVDs.


X

On Sun, 15 Oct 2006 17:47:08 -0400, Carlos Moreno
wrote:


I've been watching HDTV on my SDTV set for a couple months now,
and I'm close to jumping to an HDTV (or maybe EDTV, if the budget
so requires) set.

But I'm so confused when I see the specs, specifically the native
resolution (which I assume is the size of the physical grid of
pixels -- i.e., the *actual* amount of pixels horizontally and
vertically).

My confusion is: if the standard resolutions are 480, 720, and
1080, then why aren't the panel resolutions restricted to sizes
that match *exactly* those, at 16:9 ratio?? The way I see it,
there should *only* be panels with resolutions 854 x 480,
1280 x 720, and 1920 x 1080.

Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).

The second part of my question is: what do those TV sets do
with the signal? "Resample" it to fit the panel's resolution?
Is there not a noticeable deterioration in the quality of the
signal?

In particular, what do TV sets with 1360 x 768 do? Do they
"crop" in the panel's area and use the middle 1280 x 720??
Or do they stretch/resample the signal to expand it to take
the full panel's area?? Seems gratuitous to me -- why wouldn't
they simply make the panel 1280 x 720??

BTW, don't be afraid to get technical -- I'm an Electronics
Engineer, and have done some work on Image Processing, so feel
free to throw technical/mathematical arguments if needed.

Thanks,

Carlos


HDTV was built by committee. It sucks.

HDTVs are built by the usual scum. It shows.

I'd quit worrying about it, and buy the set that looks the best to
you. You know what you want to use it for and what style you want.
e.g. bigger is better ?

"Carlos Moreno" wrote in message
...
Leadfoot wrote:


But still, the physical aspect ratio of the panel is 16:9. If
you plug your PC (at a resolution of 1024x768), then the image
would look horizontally stretched -- unless they resample it,
which would defeat the argument of using 1024 x 768 because
that's a typical resolution of PC or game consoles. Sounds
quite strange to me.

Sharp gives you a choice when connecting to a PC. If you choose 1:1 mapping,
then 1024 x 768 would display as such, with black bars on the sides. There
would be no resampling. One way of looking at this is that they took a 1024
x 768 panel and made it wider.

Note that this goes beyond TV panels. 17 and 19 inch LCD PC displays tend to
have a 1.25 to 1 aspect ratio, instead of the 1.33:1 we are used to with CRT
displays (640/480=1.333). So, if you have your video card set for 1024 x 768
you will get a display that is elongated vertically. You fix that by setting
the video card to 1280 x 1024. I just went through that with my 19" LG
display.

Tam

Tam

Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).

The second part of my question is: what do those TV sets do
with the signal? "Resample" it to fit the panel's resolution?
Is there not a noticeable deterioration in the quality of the
signal?

Be happy you noticed this. Now you can avoid buying such poorly engineered
displays.

Tam/WB2TT wrote:

Note that this goes beyond TV panels. 17 and 19 inch LCD PC displays tend to
have a 1.25 to 1 aspect ratio, instead of the 1.33:1 we are used to with CRT
displays (640/480=1.333). So, if you have your video card set for 1024 x 768
you will get a display that is elongated vertically. You fix that by setting
the video card to 1280 x 1024. I just went through that with my 19" LG
display.

But precisely -- this supports my argument; the panel has a 5:4 aspect
ratio, and the native pixel resolution is consistent with the 5:4 ratio.

Carlos
--

tq96 wrote:
Why do I see TV sets with 1024 x 768? Or 1024 x 720? Or
1360 x 768? Or, perhaps the single most puzzling I've seen:
1024 x 1024 (the Panasonics).

The second part of my question is: what do those TV sets do
with the signal? "Resample" it to fit the panel's resolution?
Is there not a noticeable deterioration in the quality of the
signal?


Be happy you noticed this. Now you can avoid buying such poorly engineered
displays.

*sigh* ... Your comment sort of explains why my continuous
frustration seeing the sales persons confusion and uttermost
puzzling when I try to argue with them about why these
resolutions don't make sense to me... :-) (I mean, :-( )

Thanks,

Carlos
--