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Discussion Starter #1
Robert Heron from PC mag stated this. Being that it only has a resolution of 1024*768 he said it doesn't display HD. What do you guys think of this? As far as I'm concerned I can't tell the difference between this and my HD LCD that has a resolution in the 1368 area.
 

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Greetings


Where do you draw the line on what is and what isn't HD? A 42" plasma will show 786,000 pixels of the HD signal be it from 1080i or 720p.


A CRT HD tube set will show 800,000 pixels of an HD signal ... (Some will do 1300+)


A CRT RP HD set will show between 1 million to 1.3 million pixels ...


The man is mis-informed. It is HD ... down rez'd ...


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Greetings


It depends ... some boxes do 720p better ... others do 1080 better. You have to run both and decide whichis better for yourself.


regards
 

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The only requirement for HD, according to the feds, is a vertical resolution of 720 lines or more, a 16:9 display, and the capability to accept an input signal of 720p and 1080i. There are other, more stringent definitions, but those are put forward by trade and industry organizations, and so are not enforceable.


So, yes, a 42" plasma with a 1024x768 resolution is an HDTV. Whether the added resolution from a 1366x768 LCD display makes for a better picture is, of course, a matter of debate.
 

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Discussion Starter #6
Is this debate similar to digital cameras whereas the difference between a 6 megapixel camera and a 20 megapixel is minimal because the human eye can only see so much detail? I heard that 1080p sets aren't much of an improvement unless your sitting 5 feet in front of them.
 

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Greetings


No not really ... the spec has been set out that if you meet one of the requirements ... you qualify.


A 1024x768 set meets the requirement ...


It is not for us to redefine the requirements as we please.


At best, all the person above could say is that a 42" plasma showing 786,000 pixels is less than a set that does 1 million pixels.


If the passing grade for an exam is 60% ... and I got 65% ... and you got 90% ... you can't say I failed ... you simply got a better mark, but we both passed.


It's nice to have more pixels ... but there is more to a good image than just more pixels. (It explains why a 6 mega DSLR camera will take better images than a 10 mp point and shoot camera.)


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Some info:


In response to the proliferation of new digital

television (DTV) products available at a range of

price points, the Consumer Electronics Association

(CEA) has introduced more detailed definitions for

the DTV products now available to consumers. The

new product definitions, with corresponding logos

identifying each class of products, are designed

to give retailers and consumers a clearly defined

explanation of the various choices in the growing

digital TV marketplace.

NEW CATEGORY OFFERS MORE CHOICE

A new digital TV product category called Enhanced

Definition TV (EDTV) has been added between High

Definition TV (HDTV) and Standard Definition TV

(SDTV). EDTV products are digital TVs with higher

display performance than SDTV. This new category

offers consumers another range of options when

purchasing DTV products.

COMPONENT PRODUCTS CLEARLY DEFINED

The new definitions and logos also address the

component nature of many manufacturers’ television

product lines. With new definitions and logos for

“monitors†and “tuners,†consumers and retailers will

now be able to distinguish sets with integrated DTV

tuners from monitors and tuners sold separately.

Therefore, consumers can be sure that the EDTV or

HDTV monitor they purchase can be combined with

the appropriate tuner to receive digital broadcasts

and display at Enhanced Definition (ED) or High

Definition (HD) quality levels.

NEW CLARITY FOR RETAILERS AND CONSUMERS

The definitions are expected to be incorporated into

manufacturers’ television marketing materials in

the coming months. CEA’s Video Division Board

developed the definitions to more clearly define

parameters for the varying levels of DTV products

available and to make it easier for consumers to

differentiate between the types of DTV products

offered. The Board defined minimum attribute

resolution requirements that, until now, had not

existed for High Definition televisions and monitors.

Specifically, HDTV displays must have active top-tobottom

scan lines of 720 progressive, 1080 interlaced,

or higher. For the first time, consumers will be able

to understand the different technical approaches

taken by manufacturers to the display of widescreen

high definition programming, particularly on 4:3

aspect ratio HDTV displays. (Manufacturers will

disclose the number of active scan lines for a high

definition image within a 16:9 aspect ratio “letter

boxed†image area on an HDTV display).

The CEA Video Division Board also adopted two

resolutions that provide clear guidelines to manufacturers

and retailers for the advertising of DTV products

to consumers. The first resolution will allow consumers

to clearly differentiate between the new DTV sets

and analog-only televisions. The resolution states that

analog-only televisions (televisions/monitors with a

scanning frequency of 15.75 kHz) should not be

marketed or designated to consumers as having any

particular DTV capability or attributes.

In a second related resolution, the Board agreed that

the new definitions for monitors and tuners should

be used by all manufacturers and retailers to replace

general, non-industry terminology like “DTV-ready†or

“HDTV-ready.â€

This new terminology will give consumers a ‘goodbetter-

best’ choice when shopping for digital TV

products. Manufacturers created this range of definitions

so that consumers will be armed with the information

they need to make informed buying decisions across

varying budget levels.

D I G I T A L T E L E V I S I O N

P r o d u c t a n d C o m p o n e n t D e f i n i t i o n s

HIGH-DEFINITION

TELEVISION (HDTV): HDTV

refers to a complete product/system

with the following minimum

performance attributes:

Receiver—Receives ATSC terrestrial digital transmissions

and decodes all ATSC Table 3 video formats

Display Scanning Format—Has active vertical scanning

lines of 720 progressive (720p), 1080 interlaced (1080i),

or higher

Aspect Ratio—Capable of displaying a 16:9 image1

Audio—Receives and reproduces, and/or outputs Dolby

Digital audio

HIGH-DEFINITION

TELEVISION (HDTV)

MONITOR: HDTV Monitor

refers to a monitor or display

with the following minimum performance attributes:

Display Scanning Format—Has active vertical scanning

lines of 720 progressive (720p), 1080 interlaced (1080i),

or higher

Aspect Ratio—Capable of displaying a 16:9 image1

1In specifications found on product literature and in owner’s

manuals, manufacturers are required to disclose the number of

vertical scanning lines in the 16:9 viewable area, which must be

540p, 810i or higher to meet the definition of HDTV.

HIGH DEFINITION

TELEVISION (HDTV) TUNER:

HDTV Tuner refers to a RF

receiver with the following minimum

performance attributes:

Receiver—Receives ATSC terrestrial digital transmissions

and decodes all ATSC Table 3 video formats

Outputs—Outputs the ATSC Table 3 720p and 1080i/p

formats in the form of HD with minimum active vertical

scanning lines of 720p, 1080i, or higher. Additionally, it

may output HD formats converted to other formats. The

lower resolution ATSC Table 3 formats can be output at

lower resolution levels. Alternatively, the output can be a

digital bitstream with the full resolution of the broadcast

signal.

Audio—Receives and reproduces, and/or outputs Dolby

Digital audio

ENHANCED DEFINITION

TELEVISION (EDTV): EDTV

refers to a complete product/system

with the following minimum

performance attributes:

Receiver—Receives ATSC terrestrial digital transmissions

and decodes all ATSC Table 3 video formats

Display Scanning Format—Has active vertical scanning

lines of 480 progressive (480p) or higher

Aspect Ratio—None Specified

Audio—Receives and reproduces, and/or outputs Dolby

Digital audio

ENHANCED DEFINITION

TELEVISION (EDTV)

MONITOR: EDTV Monitor

refers to a monitor or display

with the following minimum performance attributes:

Display Scanning Format—Has active vertical scanning

lines of 480 progressive (480p) or higher

Aspect Ratio—None specified

ENHANCED DEFINITION

TELEVISION (EDTV) TUNER:

EDTV Tuner refers to a RF

receiver with the following minimum

performance attributes:

Receiver—Receives ATSC terrestrial digital transmissions

and decodes all ATSC Table 3 video formats

Outputs—Outputs the ATSC Table 3 720p and 1080i/p

and 480p formats with minimum active vertical scanning

lines of 480p. Alternatively, the output can be a digital

bitstream output capable of transporting 480p, except the

ATSC Table 3 480i format can be output at 480i.

Audio—Receives and reproduces, and/or outputs Dolby

Digital audio

STANDARD DEFINITION

TELEVISION (SDTV): SDTV

refers to a complete product/system

with the following performance

attributes:

Receiver—Receives ATSC terrestrial digital transmissions

and decodes all ATSC Table 3 video formats, and produces

a useable picture

Display Scanning Format—Has active vertical scanning

lines less than that of EDTV

Aspect Ratio—None specified

Audio—Receives and reproduces usable audio

STANDARD DEFINITION

TELEVISION (SDTV) TUNER:

SDTV Tuner refers to a RF

receiver with the following minimum

performance attributes:

Receiver—Receives ATSC terrestrial digital transmissions

and decodes all ATSC Table 3 video formats

Outputs—Outputs all ATSC table 3 formats in the form

of NTSC output

Audio—Receives and reproduces, and/or outputs Dolby

Digital audio

C E A D T V D e f i n i t i o n s
 

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Quote:
Originally Posted by dave43
Robert Heron from PC mag stated this. Being that it only has a resolution of 1024*768 he said it doesn't display HD. What do you guys think of this? As far as I'm concerned I can't tell the difference between this and my HD LCD that has a resolution in the 1368 area.
Of course, he is correct in the strictest sense of the technical standard.*


See Table 5.1 on page 24 and the text following in this Guide to the ATSC DTV standard at

http://www.atsc.org/standards/a_54a.pdf


The ultimate difference is really insignificant on a 42" diagonal screen. The minimum resolution for the FCC approved DTV standard which was developed by the ATSC (720 lines of 1280 pixels per line).


Consumer and retailer organizations simplify it by saying you only need 720 lines and a 16x9 aspect ratio. Dividing 720 by 9 and multiply by 16 tells us each line should have 1280 pixels for full resolution display of a 16x9 aspect ratio.


In fact, at ten feet the 480x852 resolution of the best 42" ED plasmas is better looking to many than the higher resolution because the larger plasma pixels produce a more ideal response. We have been there and done than debate in other threads.


*The U.S. has never really agreed to a definition of "HDTV", only the DTV and ATSC definitions of the global HDTV goals.
 

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Quote:
Originally Posted by dave43
Robert Heron from PC mag stated this. Being that it only has a resolution of 1024*768 he said it doesn't display HD. What do you guys think of this? As far as I'm concerned I can't tell the difference between this and my HD LCD that has a resolution in the 1368 area.
This is all about terminology. Lot's of people have correctly defined HDTV in prior posts. The point of the PC mag article (I assume) and many other similar articles that pop up from time to time is that many HD sets cannot display all the resolution (pixels) in the HD feed. No plasmas below 50" can display all of an HD feed. No plasmas today can display all of a 1080i feed. However, with all the digital compression going on, there is a real question how much of the full HD resolution actually gets through to your TV.


This is why you have to use your eyes, not a spec sheet, to decide what TV to buy.
 

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Quote:
Originally Posted by wilburpan
The only requirement for HD, according to the feds, is a vertical resolution of 720 lines or more and the capability to accept an iput signal of 720P and 1080i. There are other, more stringent definitions, but those are put forward by trade and industry organizations, and so are not enforceable.
Out of curiousity, where are you getting this definition? Does this mean that TV's like the Sharp LC20B9U-S are HD? Sharp lists it as "HDTV-Compatible" rather than "HD". One could suggest that this is because it has no digital HD tuner, but Panasonic industrial models have no digital tuner, and yet are still described as being "HD".


So it seems to me the definition might also include that the display must have 16:9 aspect ratio (?).


Or at the very least, the screen must have enough horizontal resolution to accomodate 16:9 letterboxed viewing, while still using at least 720 lines. I suppose by that definition, one could still call a 1280x1024 (1280x720 available for 16:9) "HD".


Also, you mentioned "the ability to accept and input signal of 720p and 1080i". But there have been many displays in the past (there still might be some today) that only accepted 1080i, and yet were still called "HD".
 

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The loophole is in the text immediately before the table:

Quote:
5.2.1.1 Possible Video Inputs
While not required by the Digital Television Standard, there are certain digital television production standards, shown in Table 5.2, that define video formats that relate to compression formats specified by the Standard.
The purpose of this section is to identify the standards set by trade groups for reference, but is explicitly not incorporating their full standard into the fed's definition.


SMPTE and ITU-R BT are trade groups. They can set standards, but only the feds can enforce them.


I did leave out the part about a 16:9 display. Sorry.
 

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All I can say is on my 42X3 720 and 1080 look great.
 

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Quote:
Originally Posted by cmeinck
Is it best to ouput 720p or 1080i to a 42" Plasma?
This is a good question about an issue that confuses me. My PDP has a 1366 x 768 display resolution that does not support native 720p or 1080i. In theory my belief is it is best to choose an incoming signal that results in the least amount of up/down scaling in order to display the picture on the screen (i.e. 720p) however, 1080i looks better on my PX50U than 720p.
 

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That might be because going from 1080i to 768 lines of resolution might involve less scaling than going from 720p to 768.


Counterintuitive? Let me explain:


The ratio of 1080 to 768 is 1.40625. The ratio of 768 to 720 is 1.06667. 1.40625 is closer to a "nice" fraction than 1.06667. (There's probably a better term than "nice", but I don't know what it is.) The closer the ratio of enlargement is to a nice fration, the less work your scaler will have to do, and the less artifacting there will be.


To take a ridiculous example: suppose you have a 10 line display, with alternating rows of white and black lines (5 of each). Try to scale that up to a 20 line display. That's pretty easy -- just double each line. No artifacts.


Now try to take the original 10 line display and scale it up to 11 lines. Not so easy, even though 11 lines is "closer" to 10 than 20 lines.


One might even argue that a 768 line display would do better with a 720p signal by centering the display in the middle, and leave 24 lines of black at the top and bottom of the screen. (Also the sides as well.) This works out to a 6% reduction in the size of the displayed image, but the benefit is that you would get 1:1 pixel mapping.
 

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Thanks for your reply. The combination of deinterlacing/scaling involves some type of algorithm where individual frames are combined into a progressive format and/or new pixels are created to scale up/down to the native resolution of the panel. Whatever technique Panasonic employs to accomplish this... they do it better for 1080i than 720p.
 

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something to compare it to would be opening photoshop and taking a 1920x1080 picture and resizing the image down to 1366x768...it will still look great. if you take a 1280x720 image and resize it up the picture will not look as good as the original (i understand that i'm using an analogy that's really using 1080p, but it still makes a good point)


in the 1080 line example you had more information than necessary to fill 1366x768, in the 720 upscale you have to create information to fill in the blanks and in my experience the downscale creates a better image than the upscale
 

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But, with 1080i, the scaler needs to read a block of 540, save it, read the other block of 540, and then scale it and send it to be displayed. The 720p just gets scaled and sent. I'm not sure there's an explanation that could be printed that any of us could understand, unless we had that form of engineering background. Suffice it to say that some displays do better with one vs. the other, and some people like the look of one vs. the other.
 

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Quote:
Originally Posted by optivity
This is a good question about an issue that confuses me. My PDP has a 1366 x 768 display resolution that does not support native 720p or 1080i. In theory my belief is it is best to choose an incoming signal that results in the least amount of up/down scaling in order to display the picture on the screen (i.e. 720p) however, 1080i looks better on my PX50U than 720p.
I think the reason that your Panasonic looks better in 1080i has to do with its ability to display more resolution-per-picture-height than when it receives a 720p signal. Although the set accepts the lower resolution (a newly added feature to this year's model), it is documented that at 720p it is only capable of displaying a resolution of three hundred and something per-picture-height (unlike at 1080 where it displays six hundred and something). Therefore, your situation is rather unique as it is specifict to your model. Most of the time, you want to minimize the amount of scaling done -- and you would select an input resolution that closely resembles the native of one of your TV.

BTW, This is a great read on resolution.
 
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