Slapper Posted May 9, 2008 Share Posted May 9, 2008 whats the diffrents between them:rolleyes: Link to comment Share on other sites More sharing options...
Dr_seuss25 Posted May 9, 2008 Share Posted May 9, 2008 This gives a good run down on all of the formats in an easy to understand way http://www.youtube.com/watch?v=Z-JXfyvlPh0 Link to comment Share on other sites More sharing options...
Fat Tony Posted May 9, 2008 Share Posted May 9, 2008 1080i means 1080 lines of interlaced vertical resolution. Interlaced meaning first the odd lines are are scanned, 1,3,5,7,9 all the way to 1079 and then 2,4,6,8 etc. 2 scans of the whole screen make one picture. Progressive takes only one scan 1,2,3,4 etc and this makes for a smoother picture. Link to comment Share on other sites More sharing options...
nixon76 Posted May 10, 2008 Share Posted May 10, 2008 Dr_seuss25;62878 wrote: This gives a good run down on all of the formats in an easy to understand way http://www.youtube.com/watch?v=Z-JXfyvlPh0 Thats a good video. Lays it out nice without getting bogged down in the detail (and the detail can be pretty confusing). Interesting that he states 720p is better than 1080i. But nice that he adds that other people believe it's the other way - nobody is right. Link to comment Share on other sites More sharing options...
Adam1553552670 Posted May 10, 2008 Share Posted May 10, 2008 That video clip is a little misleading, at least in the context of HDTV in New Zealand. The 1080i/720p comparison he makes is only relevant to broadcast HDTV (such as Freeview HD). For any natively progressive media (Blu-ray Disc and HD DVD) it doesn't apply as the interlaced video can be deinterlaced into 1080p without any loss, and there is virtually no chance that the video will be viewed in an interlaced format. Under normal conditions when watching natively progressive 1080p HD output at 1080i or 1080p you won't see any difference at all, and 1080i will be significantly better than 720p. Link to comment Share on other sites More sharing options...
Stuzzo1553552685 Posted May 10, 2008 Share Posted May 10, 2008 Just further on that subject, I understand most US TV shows are filmed natively in 1080p24. Now to show them here in 1080i50 (TV3) I asume each progressive frame is split into two interlaced fields (and speeded up slightly) so this should mean that a display should be able to recombine them into pristine 1080p progressive material. Would there be a flag in the mpeg stream to tell the display it's derived from a progressive source or is it left to the display to work it out? This would kind of give one area of advantage to the 1080i camp surely? Link to comment Share on other sites More sharing options...
nixon76 Posted May 10, 2008 Share Posted May 10, 2008 Stuzzo;62904 wrote: Just further on that subject, I understand most US TV shows are filmed natively in 1080p24. Now to show them here in 1080i50 (TV3) I asume each progressive frame is split into two interlaced fields (and speeded up slightly) so this should mean that a display should be able to recombine them into pristine 1080p progressive material. Would there be a flag in the mpeg stream to tell the display it's derived from a progressive source or is it left to the display to work it out? This would kind of give one area of advantage to the 1080i camp surely? This is where is all gets very confusing! :confused: Link to comment Share on other sites More sharing options...
Dr_seuss25 Posted May 10, 2008 Share Posted May 10, 2008 Yeah gets a bit full on. Currently i subscribe to the theory that 720P does look nicer than 1080i, plus at my viewing distance of about 4.5m it shouldnt matter too much Link to comment Share on other sites More sharing options...
Slapper Posted May 11, 2008 Author Share Posted May 11, 2008 Found this http://www.hometheaterhifi.com/volume_14_1/feature-article-1080p-3-2007-part-1.html Link to comment Share on other sites More sharing options...
Mycenius Posted May 15, 2008 Share Posted May 15, 2008 Another way of looking at it - Millions of Pixels displayed per second (taken from DBNZ white paper): Attached files Link to comment Share on other sites More sharing options...
Stuzzo1553552685 Posted May 16, 2008 Share Posted May 16, 2008 Except the 1080p60 in the chart is a bit of a rarity. Available content for 1080p material is mostly 1080p24/25 0r 30. 1080i50 seems to have the advantage in some areas like movies, in particular, where you can reconstruct the exact progressive source. For motion intensive content like sport 720p50 should be better. A formula I read recently is: Perceived resolution = pixels X replacement rate (refresh) which, of course, is what the chart above is showing but the eye can perceive the judder of slow frame rates. Link to comment Share on other sites More sharing options...
Mycenius Posted May 16, 2008 Share Posted May 16, 2008 Stuzzo;63260 wrote: Except the 1080p60 in the chart is a bit of a rarity. Available content for 1080p material is mostly 1080p24/25 0r 30. True, except newer 1080p capable devices extrapolate out 60 frames from the original 24 frames, or in the case of Blu-ray have had it done already - as is discussed in the article Slapper posted above... And as noted a 1080p/24 converted to 1080p/60 for displaying on a 1080 HD panel is (in theory) the nicest/cleanest/smoothest form of upconversion... So in terms of the data (volume & quality) displayed on screen its not necessarily an inaccurate comparison... Link to comment Share on other sites More sharing options...
OrangeDrink Posted May 16, 2008 Share Posted May 16, 2008 mycenius;63282 wrote: True, except newer 1080p capable devices extrapolate out 60 frames from the original 24 frames, or in the case of Blu-ray have had it done already - as is discussed in the article Slapper posted above... And as noted a 1080p/24 converted to 1080p/60 for displaying on a 1080 HD panel is (in theory) the nicest/cleanest/smoothest form of upconversion... So in terms of the data (volume & quality) displayed on screen its not necessarily an inaccurate comparison... Hardly... 1080p24 material converted to 1080p60 will judder... Showing on a screen capable of 72Hz would be closest to the original source material. It'd just repeat each frame 3 times. Converting to 60 frames a second inevitably shows some frames more than others Link to comment Share on other sites More sharing options...
Stuzzo1553552685 Posted May 16, 2008 Share Posted May 16, 2008 mycenius;63282 wrote: True, except newer 1080p capable devices extrapolate out 60 frames from the original 24 frames, or in the case of Blu-ray have had it done already - as is discussed in the article Slapper posted above... And as noted a 1080p/24 converted to 1080p/60 for displaying on a 1080 HD panel is (in theory) the nicest/cleanest/smoothest form of upconversion... So in terms of the data (volume & quality) displayed on screen its not necessarily an inaccurate comparison... The chart is showing the "source signal" in a bandwidth type comparison and it's a very good way to compare that aspect. If you take Blu-ray, the highest video formats specified are 1080p24, 1080i50/60 (please correct me if I'm wrong, the Wikipedia Blu-ray/HD-DVD comparison I learned this from has now been modified). There is no 1080p50/60 in the Blu-ray Rom specification to my knowledge. AVCHD, designed for HD camcorders, is capable of it. You can turn 1080p24 into 1080i50/60 and get it back again but you can't turn it into 1080p50/60 without adding information ie frame doubling or deinterlacing. You could equally say 720p is 1080p on a 1080p native screen but the display is adding information when it scales the image. In the end, the comparison of 1080i to 720p is going to be somewhat subjective because they each may suit different environments and each are subject to a processing stage to reach the screen. Link to comment Share on other sites More sharing options...
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