HomeTheaterMag: There is NO DIFFERENCE between 1080i and 1080p movies
A few weeks ago we answered the question on whether or not you can tell the difference between 1080i and 1080p. Many of you didn't like what was said or simply read it wrong, but HomeTheaterMag has a great write-up on why there isn't any difference between 1080i and 1080p. Geoffrey Morrison is writing with HD DVD and Blu-ray in mind as that is the only place you can get 1080p material right now. He explains it technical very well but also provides an abridged version at the end of the post. We highly recommend this post as it is filled with all the info we left out of our layman's post. 
Filed under: Misc
Reader Comments (Page 1 of 1)
Kevin @ Aug 14th 2006 2:15PM
I have still not seen anyone else mention the fact that the biggest advantage to a 1080p television is that it can accept and display 1080 lines of resolution. Period. Regardless of whether the input is 1080p or 1080i, no other lcd or plasma television can accept 1080 lines. All others would be 720p or 768p. Someone PLEASE tell me if I am wrong, but it seems to me that this is the reason to get a 1080p television.
Ben Drawbaugh @ Aug 14th 2006 2:19PM
Kevin,
You are right, it is really about 720p vs 1080p. In regards to this post they are simply talking about sources not displays.
Parris @ Aug 14th 2006 2:43PM
If you have a television that can natively display 1920 x 1080 (and I do) then there is no way your naked eye will be able to tell if one is being displayed interlaced or progressive. The whole 1080p hype is nothing more than marketing material
Belcho @ Aug 14th 2006 2:47PM
The big thing that I've heard is that 1080p won't make enough of a difference unless you're talking big screens, like 50"+. Because on a smaller screen, the lines of resolution are smaller and you wouldn't be able to tell the difference anyway.
hmurchison @ Aug 14th 2006 3:42PM
Not surprised. Many of the "its teh bettar because of 1080p" people where the ones with the least techical knowledge spouting off. If the orginating format is progressively stored and proper flags are present reconstructing the original image should be transparent. Any 1080p screen worth its salt and money should have a decent de-interlacer and scaler.
plaque monster @ Aug 14th 2006 4:27PM
So, make sure you digital display has a good video processing which processes 1080i --> 1080p correctly. Eventually, all TVs will do so, but, not yet.
Big Sam @ Aug 14th 2006 4:57PM
This is a really good article. Especially when combined with the article about which TVs bob or weave.
SJ @ Aug 14th 2006 5:39PM
I downloaded quite a few 1080i clips and tested them on a 1920 X 1200 24" display. I used VLC Media Player, which allows several options for de-interlacing, such as bob and weave. Some gave horrible results, but the perfect option was 'mean'. That produced a great, smooth video which looked similar to 1080p videos I have seen.
I am no expert, but I don't really think there's any difference between 1080i and 1080p.
Mike @ Aug 14th 2006 5:42PM
Everybody thought I was nuts to buy my Panny 34" CRT HDTV. While everyone was ooh!!-ing and ahh!! over their thin tv's I've been enjoying full native 1080i for some time now. I love to invite them over and watch their jaws hit the floor. Sure it takes 3 or 4 people to move it but what the hell...isn't it about the quality of the picture?
WiFiSpy @ Aug 14th 2006 5:51PM
1080p24 film based can be delivered as 1080i60 with no loss in quality , then can be deinterlaced (inverse telecine) back to 1080p24 (no quality loss).
jdb @ Aug 14th 2006 6:51PM
This article is correct, yet incorrect.
In the world of progressive sourced film that is interlaced in 3:2 cadence the article is spot-on. Most TVs will detect the 3:2 cadence, and reproduce the original progressive output.
There are two problems, however. Source that isn't progressive and progressive source that doesn't use the 3:2 cadence.
The article claims that most HDTV shows are filmed at 24fps. That's misleading. Newscast and sports are typically filmed at 1080i60. The HD TV series are also mixed pretty well between 1080i60 and 1080p24, with neither standard being more common.
Likewise, sources such as animation and anime tend to use cadences other than 3:2, although 3:2 is slowly becoming more common.
The video processor in a TV is designed to be inexpensive, not great. It can usually do 3:2 (film) detection and therefore deinterlace 3:2 content perfectly. For HD-DVD and Blu-ray film material, this will be fine.
Interlaced sourced HDTV, non-3:2 cadenced progressive sources, and traditional 480i SDTV, however, cannot be perfectly reconstructed. The video processor in a TV will do a very poor job on this material. This is why outboard video processors (Vantage HD, Crystalio II, Lumagen, etc) exist. The newer video processors do a fantastic job deinterlacing and scaling all material; much better than the cheap single-chip solution in a TV.
You can tell the difference between 1080p and 1080i, just not on 3:2 film. Spend some time in the video processor section of AVSForum and you can find countless test patterns as well as to HDTV programs that lose tons of quality being feed into a 1080i set; but look fantastic when feed through an outboard VP or HTPC and then sent progressively to the set.
1080p inputs are a requirement if you want to use an outboard video processor or upscaling HTPC (esp. non-3:2 DVDs such as anime and old TV shows).
jdb @ Aug 14th 2006 6:57PM
Typo correction: anywhere I said 1080i60 in my previous post should say 1080i30.
Joseph R @ Aug 14th 2006 9:54PM
A few months ago in a Widescreen Review interview, JOE KANE said that there *IS* a noticeable difference [vs a 1080i output] when viewing 1080p/24 mastered HD DVDs that are sent to a 1080p/24-input display!
The display MUST exactly accept "1080p/24" [not just the other types of 1080] *IF* you wanted to really see a superior difference (over 1080i) - especially in relation to moving images.
Rickdiculous @ Aug 15th 2006 1:34PM
OK, this is starting to bug me. Blu-ray and HD-DVD are NOT the only 1080p sources currently available. There are a number of graphics cards on the market that output this resolution. And while I agree that not everyone is going to hook their computers to their HD displays, many are. If that weren't the case then Microsoft wouldn't be pushing Media Center and Media Center extenders. Apple wouldn't be making such a fuss about Front Row, either (and by some claims the Mac Mini make perfect HTPCs).
The high-def market is driven largely by people such as ourselves who play PC games and use our PCs as DVRs. So, there. PCs can output 1080p, and most of the time it looks better than ANYTHING I've seen from HD-DVD or Blu-Ray.
Toadyyy @ Sep 14th 2006 6:32AM
To Rickdiculous:
the PC may be able to create a 1080p output, but it is still reliant on the source media. So a DVD deinterlaced correctly and upscaled up the PC to 1080p will look truly phenomenal. However take exactly the same hardware/software but use a HD-DVD disc as the incoming material and the image is several times better. Not just because the material is natively 1080p (and hence does not require lossy upscaling) but also because there is far more information on the HD-DVD disc for your PC and display to use to draw the final image. You have obviously seen some bad HD demos to say your PC is better (which is not a surprise as many HD demos are 1080i to displays which cannot apply inverse telecine as discussed above). Regarding HD clips via PC and same HD via disc (BD or HDDVD) I have found very, very few HD movies available for download that can compare to their HD-DVD/Blu-Ray counterparts. Most are overly compressed and/or upscaled from the original SD master rather than truly HD.
To WifiSpy (although jdb has covered it):
ONLY 1080i that started life as 1080p can be put back to 1080p. There are some cases of different cadences, but mainly because so much 1080i material is recorded interlaced to begin with.
It's even worse for us over the pond. 2:2 cadence detection is far more difficult that 3:2, very few displays even have this for SD let alone HD!!! Basically we're all up shit creek over here, with the only paddle being dedicated video processing