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Old April 14th, 2008, 07:55 PM   #46
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Originally Posted by Aaron Courtney View Post
I am going to have to disagree with you here, Ken. IMO, there were no artifacts present because we were watching interlaced footage on interlaced televisions! There was no de-interlacing. Everything was speaking the same language.

I am in the fortunate position to own both an interlaced HDTV and a couple progressive HDTV's (PDP & LCD). If I watch SD DVD's (480i material) on the progressive sets, I can spot interlaced artifacts - easy to see the jaggies on the edges of circular objects as the camera is panning across them. If I watch that same DVD on the Sony interlaced CRT, presto, jaggies are gone! Sure, the image is "softer" but I'd rather have that than distracting artifacts.
Yeah, we will certainly agree to disagree on this one! I've never seen any NTSC TV that didn't produce interlaced artifacts. This was a very well known issue with our NTSC system...I'm really surprised you never saw this.

As far as fixed pixel devices such as plasmas, I think you may be living a bit in the past. Most of the modern plasmas of today have virtually perfect deinterlacing. This is a very easy accomplishment for any decent plasma of today. Take a look at Gary Merson's tests on this and you'll see the vast majority of HDTVs he tested did perfectly in this regard.

My Pioneer presents virtually no interlaced artifacts with 60i. So for me this is simply a non-issue. This is why I prefer the significantly higher resolution of 1920X1080i broadasts to 720p broadcasts. But again, each to his own.

Oh, and one last thought. Not many people are aware that over 90% of scenes on TV are static or nearly static in nature (including sports!). So even the issue of fast movement as a plus for 720p is somewhat exaggerated.
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Old April 15th, 2008, 12:06 AM   #47
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We may be missing each other with semantics. I'll give you a specific example. I dropped by my parents' house with one of my kids last year. They have a really nice Sony XBR(3?) 52" LCD that was playing Cars to help keep my kid in check while we visited. We also have the DVD so I started to watch a bit more closely. One of the scenes in the middle of the movie begins with McQueen in court. During the opening of that scene, the picture pans across the statue in front of the courthouse. At one point in that pan, you can see quite a bit of artifacting present in the grill of that statue, which I showed my dad. It's when the local law enforcement says, "The Radiator Springs court is now in session" or something along those lines. I remember the audio better because we went back and forth comparing the de-interlacing capabilities of the display vs. the upconverting DVD player and the dialog got embedded into my brain, LOL!

Inside the courtroom, the picture at one point pans across the VW van. The circular emblem of the VW displayed severe jaggies during that pan (as one would expect). I apologized to my dad for potentially ruining his future viewing experience by showing him what to look for in interlaced video playing on progressive televisions, and of course began to explain that one of the primary attractions of HDM (format war was undecided at the time) was to finally be able to get away from authoring interlaced discs.

When I got home, I played the same scenes on my PDP. My 50" plasma did not exhibit as severe artifacts probably because it is only a "720P" rez display, but they were there nonetheless. I then played the same scenes on my 34XBR970 interlaced HDTV CRT. Perfection. Although the TV could not physically compete with the raw rez of the 1080P LCD, the picture was much more pleasing and completely artifact-free.

http://www.hqv.com/technology/index1...TOKEN=50840332

I consider the above required reading on the subject of de-interlacing in today's world of consumer electronics. It also shows the degree of variability among video processing technology currently used in both display and playback devices. As I've said before, anyone who is interested can pick up one of their de-interlacing torture test discs and see how their playback chain holds up.
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Old April 15th, 2008, 06:02 AM   #48
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Aaron, I know exactly what you're talking about. But you are missing the fact that there were all kinds of nasty artifacts with our NTSC system, many of them interlaced artifacts. There were many test scenes on calibration discs once DVDs came out that vividly pointed these interlaced artifacts out. This really is a very well known issue with NTSC.

As far as what you see, it's virtually absent with a combination of a good DVD player and plasma. I've got a Panasonic BD30 Blu Ray player and together with my Pioneer plasma, I simply don't see this kind of issue.

As I said, Gary Merson did an excellent write up on this and most of the better plasma displays of today do a perfectly good job of deinterlacing. LCDs exhibit many of their own weird artifacts including motion artifacts, which is why I'd never use an LCD as my primary viewing display.

For me nothing beats the reality and overall pictrue quality of a good plasma to say nothing of a far better, much more immersive home theater experience than a small CRT. Most reviewers of the new Pioneer Kuro plasmas have called them the best TVs ever and I don't think they'd get that reputation if they displayed lots of interlaced artifacts.
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Old April 15th, 2008, 06:53 AM   #49
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I can relate to this discussion too. Until last fall I had a Sony HiScan 1080i CRT that I got almost solely to watch the output from my FX1 since the results for normal cable TV were not that good compared to the lower resolution JVC iArt TV we have in the family room. Just before Christmas I decided to treat myself to a new 40" 16x9 and at first got a Samsung LN-T4069 one of the new 120hz 1080P LCD's. I immediately disliked it the moment I got it home!!! I subsequently changed it for a Panasonic 42" 1080P Plasma which I like much better though to be honest for normal SD programming from cable the iArt CRT is far superior. My grandson's Cars DVD plays fine on both the iART and from the PS3 to my Panasonic over HDMI. What I find interesting is that my own HDV, DV or AVCHD seem to play much smoother and with apparent higher resolution for the AVCHD and HDV on the Panasonic than even the few BluRay discs that I have, they are concert videos so likely not from 24p film? Certainly the AVCHD video is like looking through a window viewing outdoor shots of my grandson.
Upconversion from the PS3 is also of interest. Some SD discs like the first Norah Jones are wonderful but others are just awful!!! The combination of scaling/de-interlacing in all the playback and display chain can lead to a lot of problems that I do not think were as evident in a consistent interlace world. The combination of using 24p video shot badly, compressed for transmission over cable as interlace and then displayed on a low cost LCD can be almost unwatchable!!!!

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Old April 15th, 2008, 12:10 PM   #50
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Ron, you bring up a couple of good points. All DVDs are not created equal. I can remember a few years back when people were talking about 'banding' with fixed pixel displays. True, many displays did have banding issues, but what many people missed was that often the DVD was the culprit!

I'd put the 'offending' DVD on my 34 Panasonic CRT HDTV and saw the same banding I saw on my Fujitsu plasma of that time! But a well mastered DVD (which are more common today than a few years ago), on a good plasma, should show not show any more noticeable artifacts than a CRT.

I really don't want to get in to the CRT vs plasma argument, but having had a few CRT HDTVs (including a Zenith 64" RP HDTV with 9" guns and the 34" directview Panasonic), I find the better plasmas produce far superior picture quality. Issues such as misconvergence, focus, linearity, purity and many others are totally missing in plasmas. That together with the far greater, more immersive size of many plasmas makes this a 'no-brainer'....at least for me. ;)
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Old April 15th, 2008, 01:46 PM   #51
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Originally Posted by Ron Evans View Post
What I find interesting is that my own HDV, DV or AVCHD seem to play much smoother and with apparent higher resolution for the AVCHD and HDV on the Panasonic than even the few BluRay discs that I have, they are concert videos so likely not from 24p film?
Funny you mention this because most concert videos are being shot at 1080/30P. So you're experiencing firsthand exactly what we're discussing here.
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Old April 15th, 2008, 01:48 PM   #52
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Actually much of the problem with 24p video on DVD rests with the DVD player and not the HDTV.
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Old April 15th, 2008, 02:23 PM   #53
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Aaron the interesting part is that within the BluRay of Shakira concert in Miami the long shots are really nice and actually look higher resolution than the close shots from the cameras in front of the stage which also have judder in the backround. IT seems that some cameras have judder and some don't as if the cameras were shooting at different frame rates!!! Interestingly the BluRay of Queen in Montreal, which was shot on film, in some respects has less judder than the Shakira disc. I don't know if this is due to the camera persons for Queen being used to film technique and thus manage the judder better than the modern camera persons using 30P for the Shakira concert!!!! Suffice it to say the Nora Jones SD video is better than either of these BluRay discs as far as motion judder is concerned. All discs played from my PS3 with latest firmware viewed on my Panasonic 42" 1080p Plasma.
THe first Nora Jones DVD is much better than the second by the way.

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Old April 22nd, 2008, 02:30 AM   #54
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Interlaced video

There is some conflicting info in this thread about how fixed pixel displays handle interlaced video. A few users said that 60i is deinterlaced to 30p. Others say that video recorded in 60i gives smoother motion than 30p. Both of these assertions can not both be true.

I have not been able to find any definitive references on the subject, but let's look at it logically. Assume that we have a native 60i video source and a modern fixed pixel display. If the 60i input stream was simply deinterlaced to 30p, then half of the motion resolution of the original 60i source would be lost! A better approach would be to use intelligent processing (deinterlacing, interpolation, etc.) to generate 60p, thereby retaining the full motion resolution. This would explain why some people perceive 60i to give smoother motion than 30p, and also why the camera manufacturers continue to use 1080/60i as their primary recording mode. If 60i was reduced to 30p on playback, there would be no reason to record in 60i.

Therefore it seems logical to conclude that modern fixed pixel displays process 60i input to produce 60p display, and 60i video does in fact give better motion handling than 30p. If anyone can prove me wrong, please do. :)
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Old April 22nd, 2008, 06:54 AM   #55
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I think that you may be correct Bob. I can playback from two players onto my Panasonic 1080p plasma. From an older combined DVD/VHS Sony player and from a PS3. The PS3 is connected by HDMI and will upscale to 1080p playing back DVD's. There is noticeably poorer motion from the PS3 over HDMI than from the older Sony DVD over component. OF interest is that playback over HDMI from my SR11 is smooth!!! So the PS3 conversion is not doing as good a job as the Panasonic.

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Old April 22nd, 2008, 07:01 AM   #56
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Originally Posted by Bob Kittleson View Post
Therefore it seems logical to conclude that modern fixed pixel displays process 60i input to produce 60p display, and 60i video does in fact give better motion handling than 30p. If anyone can prove me wrong, please do. :)
Bob, you nailed it! Can you imagine the return rate for camcorder manufacturers if their cams only offered 24p or 30p? People would be screaming about "why is my little Johnny stuttering when he runs...that's not the way he runs!"

The entire attraction of 24p and 30p in video totally eludes me. The video should not call the viewer's attention to the flaws, but rather the subject material.
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Old April 22nd, 2008, 02:48 PM   #57
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Originally Posted by Bob Kittleson View Post
There is some conflicting info in this thread about how fixed pixel displays handle interlaced video. A few users said that 60i is deinterlaced to 30p. Others say that video recorded in 60i gives smoother motion than 30p. Both of these assertions can not both be true.

I have not been able to find any definitive references on the subject, but let's look at it logically. Assume that we have a native 60i video source and a modern fixed pixel display. If the 60i input stream was simply deinterlaced to 30p, then half of the motion resolution of the original 60i source would be lost! A better approach would be to use intelligent processing (deinterlacing, interpolation, etc.) to generate 60p, thereby retaining the full motion resolution. This would explain why some people perceive 60i to give smoother motion than 30p, and also why the camera manufacturers continue to use 1080/60i as their primary recording mode. If 60i was reduced to 30p on playback, there would be no reason to record in 60i.

Therefore it seems logical to conclude that modern fixed pixel displays process 60i input to produce 60p display, and 60i video does in fact give better motion handling than 30p. If anyone can prove me wrong, please do. :)
I also wasn't able to find any truly definitive source of information, but I did find these two pages (among some others as well), that have some info that relates to this:

http://en.wikipedia.org/wiki/1080i

http://hometheater.about.com/od/tele...80ivs1080p.htm

These pages, and others, imply that 1080i is always deinterlaced when displayed on a progressive display. If it wasn't, jaggies would be visible since on a progressive display all 1080 lines are refreshed progressively.

It's hard to tell for sure, but what I read from these and other pages is that after deinterlacing, many TVs then just display the same deinterlaced frame twice in a row, resulting in a screen refresh of 60Hz, but effectively still just 30 fps in terms of the video motion. Ostensibly, this is called 2:2 pulldown.

I assume it is possible, however, that some TVs do more complex processing, such as interpolating frames to try to get closer to true 60Hz (or even 120Hz) motion. Such interpolation would be fairly complex, however, as it would have to involve motion detection in order to get a good quality interpolated frame (just doing static interpolation would not look very good). Some expensive TV's may do this, but I doubt all TVs do, especially cheaper ones probably just use 2:2 pulldown.

If somebody knows of a definitive source of information on which TVs, if any, do motion interpolation, that would be really nice.
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Old May 5th, 2008, 01:02 PM   #58
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Originally Posted by Bob Kittleson View Post
Therefore it seems logical to conclude that modern fixed pixel displays process 60i input to produce 60p display, and 60i video does in fact give better motion handling than 30p. If anyone can prove me wrong, please do. :)
You're right in the first part, but wrong on the second. Fixed pixel displays operate at 60Hz in this country. When they are fed an interlaced stream, they must de-interlace it and refresh the display at 60Hz. The problem with 30P is what is the output result of that de-interlacing. From all of the research that I've conducted on this topic, there are only a few video processing chipsets available that ignore any interlace flags with 30P video and instead properly process the stream. And by properly process, I mean detect lack of interframe motion, employ weave de-interlace process to perfectly reconstruct the original progressive frame, and then frame double to hit 60Hz refresh rate. When 30P is properly processed, it will recreate the original 30fps of video. When 60i is properly processed, it will yield the original 30 fps of video as best as is possible while minimizing any interlaced artifacts present because the two fields comprising that frame were captured 1/60 sec apart (1/50 sec in PAL). The progressive display (or output device) then frame doubles both streams to hit 60Hz refresh rate.

I have not come across ANY progressive television that is capable of doing this. I have not come across ANY AVR that will do this either. And there have only been one or two BD players EVER MADE that can do this. So everyone who complains about 30P has never seen it processed on the same level playing field (i.e., correctly processed) as 60i.

The only way you can say that 60i yields better motion handling than 30P is if your display chain properly de-interlaces 60i while it does not properly de-interlace 30P.


I'm going to edit this because the marketplace has changed since I last reviewed this issue.

http://www.hqv.com/products.cfm

This is a decent link that shows some of the products that are using the Reon chipset that has been credited with properly de-interlacing 30P video in the past. I suppose the implementation of that technology could still be questioned however. Also, ABT is set to release an HD version of their venerable SD de-interlacing chipset (the one used in that stellar Oppo SD DVD player) that is slated to be even better than the Reon. We shall see in a few months I suppose.

I also fired off an email to HQV asking for some clarification. If I get a response, I'll add it here...

Last edited by Aaron Courtney; May 5th, 2008 at 01:36 PM.
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Old May 5th, 2008, 05:30 PM   #59
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I have not come across ANY progressive television that is capable of doing this. I have not come across ANY AVR that will do this either. And there have only been one or two BD players EVER MADE that can do this. So everyone who complains about 30P has never seen it processed on the same level playing field (i.e., correctly processed) as 60i.
The way you describe things, I assume that 30P is normally sent to the TV as 30PsF, not true 30P. If that's the case, it's amazing to me that almost all TV's are too dumb to detect the lack of inter-field motion and just use weave. This actually sounds like a bad time to buy a TV and there might be a lot more good choices in a year or so.

Assuming you have software that lets you force the deinterlace method to weave (or has smarter deinterlacing), perhaps one workaround would be to use a PC for displaying 30F video to the TV, essentially just using the TV as a 60Hz monitor and letting the PC do the deinterlacing.
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Old May 5th, 2008, 06:14 PM   #60
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Therefore it seems logical to conclude that modern fixed pixel displays process 60i input to produce 60p display, and 60i video does in fact give better motion handling than 30p. If anyone can prove me wrong, please do. :)
But 2 interlaced fields equal 1 frame. Both HD and HDV 1080-60i NTSC run at 29.97 fps, same as standard definition. You can dienterlace 60i to 60p but with a hit in resolution because they are not full frames (Not true 60p). So 60i is really 59.94i or 29.97 fps....which is saying to me it's closer to 30p.....not 60p (a sort of psuedo 60p maybe....but not true).
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