1080 vs 720

[WuTangDvD]

I want to just start by recomending to read this article:
http://editorials.teamxbox.com/xbox/1544...on-of-1080p/p1/

It gave me a new understanding about HDTV but at the same time raised new questions.

One thing is clear:
1080x1920 @ 60 FRAMES per second is better than 720x1280 @ 60 FRAMES per second. AND Interlaced video sucks

but

- 1080x1920 @ 60 FRAMES per second will NEVER be broadcasted on TV stations. the amount of compression needed to fit this type of format through the broadcast channel is to high to make any sense.
http://www.alvyray.com/DigitalTV/default.htm

- 1080x1920 @ 60 FRAMES per second IS AVAILABLE on HD-dvd and Blu-ray. Put this requires "newer" TV sets.
" There are already a large number of 1080p HDTV sets on the market, which upconvert all incoming signals, including standard-definition TVs, DVDs, HDTVs and PCs, to their panels’ native resolution of 1920x1080 pixels. Ironically, these 1080p televisions can not accept a 1080p signal. Yes, you read that correctly" April 17th, 2006
maybe by now this is a moot point.....

- 1080x1920 @ 60 FRAMES per second IS AVAILABLE when playing PS3 GAMES I THINK.
This is something I would like to see confirmed.

- If you have a 1080P HDTV it will convert 1080i broadcasts (60 FIELDS/sec into 60 FRAMES/sec) using a 2:3 pulldown or deinterlacer

SO what looks better?
1080i broadcast on a 1080i TV?
1080i broadcast on a 1080P TV using a 2:3 pulldown?
1080i broadcast on a 720P TV which would modify the resolution as well as do a 2:3 pull down.

a 720P broadcast looks better on a 720P set of course
but what about if the majority of channels are in 1080i? And what about the future? meaning the best way to display a blu-ray or hd-dvd disc. It will of course look better on a 1080P TV than a 720p TV.
as more channels go HD (and soon all) how many will be broadcasted in 1080i vs 720p?

so whats left?
Old DVD's and standard TV broadcasts

720P HDTV would have to change the resolution as well as run a 2:3 pulldown right? but the switch from standard tv to 720 is less conversion than standard tv to 1080

and same deal with old dvd, or are dvd's in progressive already? regardless if they are or not its less of a stretch to go from dvd to 720 than dvd to 1080.

So what looks best:
standard dvd/TV on 1080i hdtv
standard dvd/TV on 1080P hdtv
standard dvd/TV on 720P hdtv

looking to the future, standard TV and dvd's will go the way of vhs.

I think that if you want to watch mostly standard TV channels and regular dvd's and have a xbox360 then 720P hDTv is the way to go. and its cheaper.

if you want to get a bluray/hddvd and get a lot of HD channels and have a PS3 then a 1080P HDTV is the way to go. these sets would have a better PC input resolution as well.

thoughts?

[edDV]

The XBox360 and PS3 games are authored 720p or less. 1080i and 1080p are upscaled.

HD/BD DVD discs are mostly film source encoded to 1080p/23.976 fps. To my knowledge no HD/BD discs are authored at 60 fps. The current players frame repeat 3 then 2 to get to 60 fps over HDMI. Progressive output can be 1080p or downscaled to 720p or 480p all at frame repeated 60 fps (59.94 actual). Alternately the player telecines the output to 1080i/29.97 fps (59.94 fields per sec). A good HDTV can inverse telecine back to 1080p/23.976 fps and then frame repeat 3 then 2 to get to 60 fps. In theory 1080i (inverse telecined) and direct 1080p get the same result for a good HDTV.

Again in theory, 720p games if authored to permit frame rates over 29.97 fps should look better in 720p than 1080i. The TV will upscale 720p to the native display resolution. Most games will look "better" in 720p or 480p than 1080i if fine motion detail is important. All HDTV sets accept 720p and 480p at 59.94 fps.

For most games you don't stare at static frames, you usually value detail through motion higher. That points to faster frame rate 720p or 480p as the preferred display method for 720p authored games. If you can get 60 fps at 1080p over HDMI, that means the player does the upscale rather than the TV. It may or may not do a better job.

[gshelley61]

Not only is that article about a year and a half old, but it's filled with misinformation.

Here's just one example -

"Although 1080i has 1080 lines of vertical resolution (against 720 lines of 720p) and 1920 pixels (against the 1280 pixels of 720p) per line, the fact that 1080i is interlaced, causes an overall lower resolution (in practice) than 720p."

That's completely false. 1080i and 1080p have a little over 2 million pixels per frame. 1280x720p has about 1 million pixels per frame, about half the native resolution of 1080i/1080p. A 1080i signal sent to a 1920x1080p native display is deinterlaced (the interlaced fields woven together into progressive frames) by the TV and the result is a 1920x1080 2 million pixel image, exactly the same as a 1080p signal. With film based sources, there is no resolution difference at all between 1080i and 1080p. The fact that 1080i sends the image signal as interlaced fields instead of progressive frames does not change the source or display frame resolution.

[racer-x]

1080i is made up of 2 fields that have 540 pixels of vertical resolution. They may be woven together to make 1080 pixels, but they were taken from different time instances (about 1/60 of a second apart in NTSC) so if there is movement in that frame, the frame has less usable resolution then 720p (which is progressive and has a true 720 pixels of vertical resolution.

I'll take 720p any day over 1080i.

[WuTangDvD]

Not only is that article about a year and a half old, but it's filled with misinformation.

Here's just one example -

"Although 1080i has 1080 lines of vertical resolution (against 720 lines of 720p) and 1920 pixels (against the 1280 pixels of 720p) per line, the fact that 1080i is interlaced, causes an overall lower resolution (in practice) than 720p."

That's completely false. 1080i and 1080p have a little over 2 million pixels per frame. 1280x720p has about 1 million pixels per frame, about half the native resolution of 1080i/1080p. A 1080i signal sent to a 1920x1080p native display is deinterlaced (the interlaced fields woven together into progressive frames) by the TV and the result is a 1920x1080 2 million pixel image, exactly the same as a 1080p signal. With film based sources, there is no resolution difference at all between 1080i and 1080p. The fact that 1080i sends the image signal as interlaced fields instead of progressive frames does not change the source or display frame resolution.

I know its a year old I posted the date it was written......

But racer-x is right, a 1080P TV will deinterlace the 60 FIELDS into 30 FRAMES then double or triple certain frames to reach 60 frames per second.

Also if you put together 2 FIELDS of a 1080i signal it is not same as 1 frame of 720P.
1 frame of 720P is 1/60 second of motion
1 frame from a deinterlaced 1080i signal has 2/60 of second of motion combined into 1 frame

does that make sense?

[gshelley61]

1080i is made up of 2 fields that have 540 pixels of vertical resolution. They may be woven together to make 1080 pixels, but they were taken from different time instances (about 1/60 of a second apart in NTSC) so if there is movement in that frame, the frame has less usable resolution then 720p (which is progressive and has a true 720 pixels of vertical resolution.

I'll take 720p any day over 1080i.

That only applies to 1080p native video sources or 1080p native games. For film (movies), there is no "time difference" between the fields. The frames are assembled back to their original 1920x1080 images (there are only 24 distinct frames per second with film based sources).

Even with 1080p video or games, you don't lose half the frame resolution. You may have moire or jaggies during motion sequences, but not an actual loss in frame resolution per say. The motion artifacts might reduce perceived resolution, though.

[WuTangDvD]

1080i is made up of 2 fields that have 540 pixels of vertical resolution. They may be woven together to make 1080 pixels, but they were taken from different time instances (about 1/60 of a second apart in NTSC) so if there is movement in that frame, the frame has less usable resolution then 720p (which is progressive and has a true 720 pixels of vertical resolution.

I'll take 720p any day over 1080i.

That only applies to 1080p native video sources or 1080p native games.

Do you mean 1080i

[racer-x]

It also applies to all HDV and AVCHD Camcorders that shoot 1080i. Although some can shoot in 1080p @ 24p like my Canon HV20..............

[gshelley61]

1080i is made up of 2 fields that have 540 pixels of vertical resolution. They may be woven together to make 1080 pixels, but they were taken from different time instances (about 1/60 of a second apart in NTSC) so if there is movement in that frame, the frame has less usable resolution then 720p (which is progressive and has a true 720 pixels of vertical resolution.

I'll take 720p any day over 1080i.

That only applies to 1080p native video sources or 1080p native games.

Do you mean 1080i

Sorry, yes... 1080i native video or games. 1080p native video and games sent as 1080i can also be deinterlaced succesfully to 1080p assuming the video cadence is properly picked up by the deinterlacer.

OK, to recap - film based TV series and movies sent as 1080i will look no different than 1080p if deinterlaced properly. 1080i native video (like HD sports events sent in that format) may suffer from perceived loss in resolution during motion sequences when deinterlaced to 1080p.

[WuTangDvD]

so 1080i native video is best on 1080i set. Is that not weird? i mean you buy a 1080P set which is more expensive and then you have a 1080i set and 1080i TV looks better on the cheaper set?

[gshelley61]

so 1080i native video is best on 1080i set. Is that not weird? i mean you buy a 1080P set which is more expensive and then you have a 1080i set and 1080i TV looks better on the cheaper set?

Not necessarily. The only native 1080i sets are mostly CRT tube and rear projection CRT's with far lower actual screen resolution than 1920x1080p fixed pixel displays have. Hitachi makes a couple of 1080i scanning plasmas, but again they are like 1024x1080i native.

Some 1080i native video programs (like David Letterman, Tonight Show, Conan, etc.) look awesome on my 1080p DLP. Even high motion sports 1080i video looks OK in terms of image resolution. Macroblocking (due to low bitrate re-encoding by my cable company) is a much bigger problem with high motion 1080i than deinterlacing is.

[WuTangDvD]

another recap please in a different way.

what are our video sources NOW.
DVD, HD-DVD, BLU-RAY, 1080i broadcast, 720P broadcast, standard TV broadcast.

what will bluray/hddvd look best on

what will DVD look best on

what will sdTV look best on

what will 1080i HD broadcast look best on

what will 720P HD Broadcast look best on

[gshelley61]

Everything you listed there looks best to me on large 1920x1080 native displays (assuming the signal/image processing, color reproduction, black level, contrast, etc. are also decent) with the exception of standard analog NTSC cable/broadcast... and assuming for DVD a good quality upscaling player is being used.

For analog NTSC cable and broadcast, a regular old CRT television still does the best job.

[WuTangDvD]

why would a dvd look best on 1080 tv

wouldnt there be less conversion on 720 tv?

[gshelley61]

I've owned three HDTV's. A 43" 1280x720p DLP, a 46" 1280x720p DLP and now a 62" 1920x1080p DLP. There's no comparison in my case - the larger, higher resolution DLP looks much better (of course, there have also been noticeable improvements over the last few years in signal processing, black level, contrast, color accuracy, etc.)

Top quality scalers that are in some up-conversion DVD players do a great job of producing the best possible image from a DVD. I get the sharpest, most detailed image from upscaled DVD's at 1080i with my display, not 720p. My set does not accept 1080p signals, but there is no additional upscaling involved with 1080p anyway.

[WuTangDvD]

but you see why i would think a dvd should look better on a 720P set right?

[SCDVD]

There is a problem with the bandwidth on broadcast HD. The constricted bit rate that results from the bandwidth limitation tends to cause compression artifacts particularly on the edge of objects where there is a sharp contrast with the background as well as motion. This can sometimes be quite distracting.

[gshelley61]

but you see why i would think a dvd should look better on a 720P set right?

Yes, but the simple fact is a 1920x1080 native display has more than twice the pixels that a 1280x720 native display has. The resulting images can be larger, with little or no screen door effect, and an even more film-like appearance. Display size and seating distance play a major role in all this, of course. A 42" 1920x1080p display is irrelevant at 10 ft (too small at that distance to discern the additional resolution capability).

[WuTangDvD]

There is a problem with the bandwidth on broadcast HD. The constricted bit rate that results from the bandwidth limitation tends to cause compression artifacts particularly on the edge of objects where there is a sharp contrast with the background as well as motion. This can sometimes be quite distracting.

in regards too.................?

"Yes, but the simple fact is a 1920x1080 native display has more than twice the pixels that a 1280x720 native display has. The resulting images can be larger, with little or no screen door effect, and an even more film-like appearance"

I dont know about this. maybe I think the conversion is bigger deal than it acutally is.

[gshelley61]

I dont know about this. maybe I think the conversion is bigger deal than it acutally is.

Today's scalers and deinterlacers are very good, some are exceptional. Minimizing conversion steps sounds important in theory, but in the real world it is a pretty seamless and succesful process. The main thing is to set up your particular display and source equipment to whatever settings look best to you. Each combination of specific models of displays and source equipment produces slightly different results, so in the end you have to go with what looks best to you when you are watching actual content (like a movie or TV program).

[jagabo]

but you see why i would think a dvd should look better on a 720P set right?

Yes, but the simple fact is a 1920x1080 native display has more than twice the pixels that a 1280x720 native display has. The resulting images can be larger, with little or no screen door effect, and an even more film-like appearance. Display size and seating distance play a major role in all this, of course. A 42" 1920x1080p display is irrelevant at 10 ft (too small at that distance to discern the additional resolution capability).

Also keep in mind that there are few 720p displays with native 1280x720 resolution. Any incoming 720p signal will be resized to the native resolution of the TV. Even with a native 1280x720 resolution most displays will overscan the frame -- they will enlarge the frame by about 5 percent and then cut off 5 percent of the image around the edges.

So both 720p and 1080p displays will resize an incoming 720p signal. The 720p display is not likely to look better than the 1080p display.

In fact, it can be argued that enlarging by ~55 percent (720p to 1080p plus overscan) will give better results than enlarging by 5 percent (720p plus overscan) assuming that they are both displayed at the same physical size. Enlarging by small percentages leads to severe moire artifacts. Here's are some crops from an original image, one enlarged by 5 percent and another enlarged by 55 percent:



Notice how the 5 percent enlargement has much more severe moire artifacting? This is because the larger display has more "in between" pixels to work with. (Keep in mind that both of them would be displayed at the same physical size on the TV screens, the 720p display would simply have larger pixels than the 1080p display.) Of course, real video wouldn't have lines this sharp but there are times when moire artifacting can be quite visible.

As far as upscaling SD resolutions to 720p or 1080p displays, the quality of the deinterlace and upscale filters will be more important than the difference in native resolution.

[WuTangDvD]

hmmm intresting.

[WuTangDvD]

how does somebody know if a tv set has a good deinterlacer or upscale filters

[WuTangDvD]

i found it
http://digitalcaffeine.com/hd/

If you are a hardcore sports fan I guess get a 720P TV otherwise 1080 is the way to go.

[gshelley61]

720p sources (ABC, Fox, ESPN HD) all look great on my 1080p DLP.

Most of the newer brand name sets have excellent scaling and deinterlacing processors.

[SCDVD]

Brightness and contrast are the two most important factors for the viewers perception of TV quality. Resolution is good but its third on the list.

[WuTangDvD]

Ive heard that before but that should have nothing to do with what format your TV is but more of what type of technology your TV is , DLP LCD CRT or plasma.... I could be wrong though.

[gshelley61]

Brightness and contrast are the two most important factors for the viewers perception of TV quality. Resolution is good but its third on the list.

Resolution becomes much more important as the screen size gets larger, the seating distance gets shorter and the source content becomes more detailed (is high definition). All image quality factors are really equally important. There are plenty of cheap portable black and white TV's with great contrast and excellent blacks, but terrible picture detail (and no color, obviously). How about a 13" bedroom color tube TV? Some have great contrast, blacks, and color... no good for watching high definition, though. Small tube TV's have very low resolution shadow masks that make DVD's look about the same as VHS.