High Definition screen modes and resolution explained - Club CD Freaks

**Dee-27** · 16-11-2007

You may quite possibly have seen the specifications in your local electrical retailer, with LCD and Plasma TV sets carrying the “HD Ready” logo. But what does this actually mean?

The TV’s screen must support 720p and 1080i screen modes. The TV must also support HDCP compliance. The native resolution supported must be equal or greater than 1,366x768 pixels. This means that 1080i signals will be downscaled to fit on the screen as they are larger than a 1,366x768 screen will allow.

A newer standard has already been released called “Full HD”. Full HD must be able to support 1080p. 1080p requires a minimum resolution of 1,920x1,080 pixels. So for the moment these displays tend to cost a bit more than a standard HD Ready TV.

What is the difference between an interlaced (i) and progressive (p) screen mode?

Regardless of the resolution, the picture you see on your TV screen is made up of picture frames displayed sequentially. Each frame contains a number of horizontal picture lines that make up that single frame.

Interlaced
For the old analogue PAL TV system (used in Europe) which uses 576i (interlaced). Each picture field contains 288 horizontal lines of picture data. Why 288? The term “interlaced” means that in order to see one complete frame of picture data, each frame takes two scans to perform. In the first half frame, each “odd numbered” horizontal lines are displayed (field 1), and in the second scan, each “even numbered” horizontal lines are displayed (field 2). The PAL system allows 25 picture frames to be displayed per second. (exactly half of the 50 frames per second available).

So let’s see what that actually means when High Definition interlaced picture screen modes are used.

720i contains 360 horizontal lines of picture data per field (2 fields = 1 frame).
1080i contains 540 horizontal lines of picture data per field (2 fields = 1 frame).

Progressive
Progressive is much easier to understand. Each picture frame contains all the available horizontal lines of picture data. There is no need to break the frame of picture data into odd and even horizontal lines and display them as two half frames. This also means the complete picture frame rate is now 50 frames per second, which results in a more detailed, flicker free picture on your TV screen

Now let’s see what that means when High Definition progressive screen modes are used.

720p contains 720 horizontal lines of picture data per frame
1080p contains 1080 horizontal lines of picture data per frame

So what does all this add up to?
The human eye is most sensitive to horizontal lines of picture data. In other words, the more horizontal lines of picture data that can be displayed, the more detailed and smooth the picture will be. A 1080p frame of picture data will contain around four times the detail of an old analogue PAL TV screen.

So those are the facts and figures.
Which display modes are supported by your HD TV?
How does your HD TV perform with HD content?
Would you consider upgrading to "full HD"?
Will you just buy "full HD" to start with?
Let's hear your views.

**zevia** · 16-11-2007

Quote:

Originally Posted by Dee-27

Which display modes are supported by your HD TV?
Would you consider upgrading to "full HD"?
Let's hear your views.

I bought my 42" Samsung Plasma display 1080i early this year, quite a big jump for me and my wallet given the price at that time so I'm not sure if I will upgrade to Full 1080p soon.

Quote:

How does your HD TV perform with HD content?

The picture quality is just perfect for me. Well at least for HD content, but watching standard definition channels from FIOS on this TV is baad! I can see pixelations.

Am I correct that plasma has better picture quality than LCD?
Also I read that 1080p is only good on a 46" or higher?

CDan · 17-11-2007

Quote:

Originally Posted by zevia

Am I correct that plasma has better picture quality than LCD?
Also I read that 1080p is only good on a 46" or higher?

Not really. There are equally good and bad examples of all display types. It's not so much what's in the screen as it is what's behind it. Crappy electronics, unfortunately, are common. Many people find that rear projection LYCOS-type sets provide the best combination of large screen size, price and picture quality. As costs decline, plasma and LCD will probably become the norm, and rear projection may eventually die off. But your best bet is to preview all the types, and don't rule out 1080i or even 720p sets either, until you see them. Ignore prices until you settle on a particular technology and brand. You will not see much, if any, difference between 720p and 1080p on screens smaller than 50" unless you sit VERY close.

IMHO, the fastest way to separate the good electronics from the crap is to view them while displaying DVD content, or even broadcast quality. If they can upscale and create a good image from that, you're bound to be satisfied.

**Dee-27** · 20-11-2007

I personally prefer Plasma, as Plasma is faster at refreshing the display compared to LCD. Maybe Plasma displays do not have a high contrast ratio's compared to LCD, or are maybe not so bright. They of course use more energy compared to LCD display. But i just prefer the way the picture looks on a Plasma display.
.
I also agree what CDan says. There are good and bad displays. Having said i prefer Plasma. I would rather have a good LCD display panel rather than a bad Plasma panel.

Many manufacturers selling FULL HD TV's here in the UK are selling them from size 37 inch and above. I can't comment if that is the size at which point you notice a difference, or at the moment, it requires that size of display to accommodate 1,920x1,080 pixel resolution.

_chef_ · 20-11-2007

Don't underestimate 24p and 100Hz (50/60Hz).

oldtecho · 23-11-2007

Hi Dee-27
I think your explanation of interlaced and progressive needs a bit of clarification. I will see if I can explain this a bit better. In the interlaced scanning system the group of 288(PAL) lines you refer to are known as a "field" and they occur 50 times a second. When you add the 2 fields together you get a "frame" of 576(PAL) lines that occur at 25 times a second. The same applies to 720i and 1080i there are 720 lines and 1080 lines but they occur at 25 times a second. There is no resolution difference between 1080i and 1080p as they are both 1920x1080. "But" 1080p will look a lot better than 1080i because of the reduced flicker and the lack of distortion effects on motion in the picture because all the lines are scanned at once.

**Dee-27** · 23-11-2007

Thanks for the clarification oldtecho.
Am i correct in saying that with an interlaced display, only half of the available lines that make up a full frame are displayed at a time, hence the flicker with interlaced?
So for example for 720i, two "fields" of 360 lines that make a frame are displayed sequentially?
And if this is the case, i need to change the term "frame" to "field" in some instances of my explanation?

oldtecho · 24-11-2007

Hi Dee-27
You are correct in saying that with an interlaced display, only half of the available lines that make up a full frame are displayed at a time. In your case of 720i the first field (field1) displays lines 1-3-5-7-9 etc to line 719 in a 50th of a second. The second field (field2) displays lines 2-4-6-8-10 etc to line 720 in the next 50th of a second. Then when the 2 fields are interlaced together (hence the term interlaced) on your display to form one frame you see 720 lines in a 25th of a second giving you flicker.

**platinumsword** · 24-11-2007

Many people who first watch non-HDTV on their new high-def televisions are disappointed by how it looks. But it's not the television's fault. The single most important ingredient in picture quality is the source, and lower-quality standard-def TV, especially compared to HDTV, looks bad. The difference is often compounded by the fact that HDTVs are bigger and sharper than regular TVs and thus highlight the flaws of low-quality sources even more. No matter how nice of an HDTV you get, standard-def TV, at least compared to DVD and high-def, will look a lot worse.

Let's just keep it this simple, or else we could get into some serious stuff that would only create a lot of confusion for people.

pradeep_rad · 11-12-2007

Is it necessary to have HD content to have the HD experience?

_chef_ · 11-12-2007

Quote:

Originally Posted by pradeep_rad

Is it necessary to have HD content to have the HD experience?

If you have a device with a hardware upscaler built in you can have that HD experience too.

t0nee1 · 11-12-2007

I'm going to set my 50" plasma to display in 720p instead of the 1080i mode it's set at...Should look better ...It already looks great, i.e. no noticeable flickering .... but I've gotta see if displaying the 720 lines scanned at once makes any significant difference....What you guys/gals think?.... has anyone tried and compared on your sets?.....

**Dee-27** · 12-12-2007

Quote:

Originally Posted by t0nee1

I'm going to set my 50" plasma to display in 720p instead of the 1080i mode it's set at...Should look better ...It already looks great, i.e. no noticeable flickering .... but I've gotta see if displaying the 720 lines scanned at once makes any significant difference....What you guys/gals think?.... has anyone tried and compared on your sets?.....

It should depend on the native resolution of the set. But other factors have to be considered too. Does the set support 100Hz for example.

Our lounge can't accommodate a large set. We have a 32 inch set that supports 1080i. On that set, 720p certainly looks better.

I would certainly try 720p, you may be surprised by the result.

CDan · 12-12-2007

Quote:

Originally Posted by _chef_

If you have a device with a hardware upscaler built in you can have that HD experience too.

Um, not really. Only 1080 content should be considered "HD". Upscaling 480 to 1080 is not HD.

**zevia** · 12-12-2007

Quote:

Originally Posted by pradeep_rad

Is it necessary to have HD content to have the HD experience?

If you have an HDTV, I would say "near HD experience" and I can confirm that at least in my setup.

I still have DVD player connected via component upscaled to 1080i and it's huge difference compared to watching 480i on my previous setup.

**platinumsword** · 12-12-2007

Quote:

Originally Posted by t0nee1

I'm going to set my 50" plasma to display in 720p instead of the 1080i mode it's set at...Should look better ...It already looks great, i.e. no noticeable flickering .... but I've gotta see if displaying the 720 lines scanned at once makes any significant difference....What you guys/gals think?.... has anyone tried and compared on your sets?.....

You should see some difference especially with fast motion.

16-11-2007	#1 (permalink)
Dee-27 Administrator and Reviewer Join Date: Jul 2004 Location: Scotland, UK Posts: 8,159	High Definition screen modes and resolution explained <a href='http://adstats.cdfreaks.com/www/delivery/ck.php?n=a13febf7&cb=INSERT_RANDOM_NUMBER_HERE' target='_blank'><img src='http://adstats.cdfreaks.com/www/delivery/avw.php?zoneid=30&cb=INSERT_RANDOM_NUMBER_HERE&n=a13febf7' border='0' alt='' /></a> You may quite possibly have seen the specifications in your local electrical retailer, with LCD and Plasma TV sets carrying the “HD Ready” logo. But what does this actually mean? The TV’s screen must support 720p and 1080i screen modes. The TV must also support HDCP compliance. The native resolution supported must be equal or greater than 1,366x768 pixels. This means that 1080i signals will be downscaled to fit on the screen as they are larger than a 1,366x768 screen will allow. A newer standard has already been released called “Full HD”. Full HD must be able to support 1080p. 1080p requires a minimum resolution of 1,920x1,080 pixels. So for the moment these displays tend to cost a bit more than a standard HD Ready TV. What is the difference between an interlaced (i) and progressive (p) screen mode? Regardless of the resolution, the picture you see on your TV screen is made up of picture frames displayed sequentially. Each frame contains a number of horizontal picture lines that make up that single frame. Interlaced For the old analogue PAL TV system (used in Europe) which uses 576i (interlaced). Each picture field contains 288 horizontal lines of picture data. Why 288? The term “interlaced” means that in order to see one complete frame of picture data, each frame takes two scans to perform. In the first half frame, each “odd numbered” horizontal lines are displayed (field 1), and in the second scan, each “even numbered” horizontal lines are displayed (field 2). The PAL system allows 25 picture frames to be displayed per second. (exactly half of the 50 frames per second available). So let’s see what that actually means when High Definition interlaced picture screen modes are used. 720i contains 360 horizontal lines of picture data per field (2 fields = 1 frame). 1080i contains 540 horizontal lines of picture data per field (2 fields = 1 frame). Progressive Progressive is much easier to understand. Each picture frame contains all the available horizontal lines of picture data. There is no need to break the frame of picture data into odd and even horizontal lines and display them as two half frames. This also means the complete picture frame rate is now 50 frames per second, which results in a more detailed, flicker free picture on your TV screen Now let’s see what that means when High Definition progressive screen modes are used. 720p contains 720 horizontal lines of picture data per frame 1080p contains 1080 horizontal lines of picture data per frame So what does all this add up to? The human eye is most sensitive to horizontal lines of picture data. In other words, the more horizontal lines of picture data that can be displayed, the more detailed and smooth the picture will be. A 1080p frame of picture data will contain around four times the detail of an old analogue PAL TV screen. So those are the facts and figures. Which display modes are supported by your HD TV? How does your HD TV perform with HD content? Would you consider upgrading to "full HD"? Will you just buy "full HD" to start with? Let's hear your views. __________________ My Review PC & Optical Drives We came to wreck everything and ruin your lives, God sent us To become a member of cdfreaks.com just click here to join The Forum Rules The NEC/Optiarc F.A.Q. Liggy & Dee's NEC/Optiarc Firmware Page Last edited by Dee-27; 25-11-2007 at 14:41.

20-11-2007	#4 (permalink)
Dee-27 Administrator and Reviewer Join Date: Jul 2004 Location: Scotland, UK Posts: 8,159	Re: High Definition screen modes and resolution explained I personally prefer Plasma, as Plasma is faster at refreshing the display compared to LCD. Maybe Plasma displays do not have a high contrast ratio's compared to LCD, or are maybe not so bright. They of course use more energy compared to LCD display. But i just prefer the way the picture looks on a Plasma display. . I also agree what CDan says. There are good and bad displays. Having said i prefer Plasma. I would rather have a good LCD display panel rather than a bad Plasma panel. Many manufacturers selling FULL HD TV's here in the UK are selling them from size 37 inch and above. I can't comment if that is the size at which point you notice a difference, or at the moment, it requires that size of display to accommodate 1,920x1,080 pixel resolution. __________________ My Review PC & Optical Drives We came to wreck everything and ruin your lives, God sent us To become a member of cdfreaks.com just click here to join The Forum Rules The NEC/Optiarc F.A.Q. Liggy & Dee's NEC/Optiarc Firmware Page

20-11-2007	#5 (permalink)
_chef_ CD Freaks Guru Join Date: Aug 2004 Location: @FX labs .de ...watching [Benders.Big.Score] [Tripping.The.Rift.The.Movie] Posts: 23,499	Re: High Definition screen modes and resolution explained Don't underestimate 24p and 100Hz (50/60Hz). __________________ Started with burning capable optical drives (CD-R) in 1997. Bought optical drives from AOpen, HP, LiteOn, NEC, Philips, Pioneer, Plextor, Ricoh, Samsung, Sanyo, Toshiba and Yamaha. *'Things are now in motion that cannot be undone.' [Gandalf, LoTR]* Enable DMA with micrAp$0ft Enable DMA free at your will busTRACE => Upper/Lower Filters Util DevCon *HOW TO ... Delete the Upper & Lower Filters!* If you expect help then please start by using the powerful SEARCH.

23-11-2007	#6 (permalink)
oldtecho New on Forum Join Date: Nov 2007 Posts: 2	Re: High Definition screen modes and resolution explained Hi Dee-27 I think your explanation of interlaced and progressive needs a bit of clarification. I will see if I can explain this a bit better. In the interlaced scanning system the group of 288(PAL) lines you refer to are known as a "field" and they occur 50 times a second. When you add the 2 fields together you get a "frame" of 576(PAL) lines that occur at 25 times a second. The same applies to 720i and 1080i there are 720 lines and 1080 lines but they occur at 25 times a second. There is no resolution difference between 1080i and 1080p as they are both 1920x1080. "But" 1080p will look a lot better than 1080i because of the reduced flicker and the lack of distortion effects on motion in the picture because all the lines are scanned at once.

23-11-2007	#7 (permalink)
Dee-27 Administrator and Reviewer Join Date: Jul 2004 Location: Scotland, UK Posts: 8,159	Re: High Definition screen modes and resolution explained Thanks for the clarification oldtecho. Am i correct in saying that with an interlaced display, only half of the available lines that make up a full frame are displayed at a time, hence the flicker with interlaced? So for example for 720i, two "fields" of 360 lines that make a frame are displayed sequentially? And if this is the case, i need to change the term "frame" to "field" in some instances of my explanation? __________________ My Review PC & Optical Drives We came to wreck everything and ruin your lives, God sent us To become a member of cdfreaks.com just click here to join The Forum Rules The NEC/Optiarc F.A.Q. Liggy & Dee's NEC/Optiarc Firmware Page

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24-11-2007	#8 (permalink)
oldtecho New on Forum Join Date: Nov 2007 Posts: 2	Re: High Definition screen modes and resolution explained Hi Dee-27 You are correct in saying that with an interlaced display, only half of the available lines that make up a full frame are displayed at a time. In your case of 720i the first field (field1) displays lines 1-3-5-7-9 etc to line 719 in a 50th of a second. The second field (field2) displays lines 2-4-6-8-10 etc to line 720 in the next 50th of a second. Then when the 2 fields are interlaced together (hence the term interlaced) on your display to form one frame you see 720 lines in a 25th of a second giving you flicker.

24-11-2007	#9 (permalink)
platinumsword Moderator Join Date: Oct 2005 Posts: 2,262	Re: High Definition screen modes and resolution explained Many people who first watch non-HDTV on their new high-def televisions are disappointed by how it looks. But it's not the television's fault. The single most important ingredient in picture quality is the source, and lower-quality standard-def TV, especially compared to HDTV, looks bad. The difference is often compounded by the fact that HDTVs are bigger and sharper than regular TVs and thus highlight the flaws of low-quality sources even more. No matter how nice of an HDTV you get, standard-def TV, at least compared to DVD and high-def, will look a lot worse. Let's just keep it this simple, or else we could get into some serious stuff that would only create a lot of confusion for people.

11-12-2007	#10 (permalink)
pradeep_rad New on Forum Join Date: Dec 2007 Posts: 2	Re: High Definition screen modes and resolution explained Is it necessary to have HD content to have the HD experience?

11-12-2007	#12 (permalink)
t0nee1 CD Freaks Senior Member Join Date: Nov 2006 Location: Wild Wild West Posts: 932	Re: High Definition screen modes and resolution explained I'm going to set my 50" plasma to display in 720p instead of the 1080i mode it's set at...Should look better ...It already looks great, i.e. no noticeable flickering .... but I've gotta see if displaying the 720 lines scanned at once makes any significant difference....What you guys/gals think?.... has anyone tried and compared on your sets?..... __________________ "Beauty is in the eye of the beerholder" "The worst vice is advice" "Better to remain silent and be thought a fool than to speak out and remove all doubt." Abraham Lincoln

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