Is 720p Real High Definition ?

[Michael Struthers]

Well if Sony hadn't crippled 1080i with that crap hdv compression I might be more inclined to buy in. So give me a low compression 1080i and I'll like it fine.

[Douglas Spotted Eagle]

Originally Posted by Michael Struthers

Well if Sony hadn't crippled 1080i with that crap hdv compression I might be more inclined to buy in. So give me a low compression 1080i and I'll like it fine.

And your opinion is based on what experience with the camera?

[Steve Mullen]

Originally Posted by Douglas Spotted Eagle

I don't know that Sony did or didn't say that HD starts with 1080, however.e.

If you look at Sony's HDV IBC statement it comes very, very close to saying ONLY 1080i is HD. I was shocked they would play that dirty a game.

There is no ATSC or QAM specification for 1080p60 -- so it doesn't really leglly exist. Sony's new camera can shoot 1080p but I know of no infrastructure than can handle 1080p60. (HDCAM SR at some point will record 1080p60.)

SO -- it is BS to say we should have skipped 720p. Even HDV is ONLY 72p30. So claiming we should have waited for 1080p60 -- which stil ain't even a legal spec AND will require every cable/DBS company cut their number of channels in half in nonsense.

Without 720p we would only have interlace video. And no matter what Sony claims -- interlace is not only horrible it is obsolete. It is the worst possible format for a world of progressive displays -- which in the HD world is about 90%. (Even Sony has phased-out CRTs.)

So not only does capturing interlace screw-up an image, FX editing screws-up interlace, and every new display when it tries to display interlace screws it up evem more.

The real slogan should be ONLY PROGRESSIVE VIDEO IS HIGH DEFINITION!.. 1080i should be called "high-resolution," but not HD. It is too plauged with artifacts to offer high DEFINITION.

All you need to do is watch sports on 1080i verses 720p. There is no comparision! 720p is pristine -- although slightly soft. But softer only in an A/B test. Nothing you would really notice.

Which is why I call the FX1/Z1HDV "under-sampled, high-resolution DV."

That's why JVC could compare their HD100 side-by-side with HDCAM.

ProHD may not be a format, but sure is much more than Sony's HDV. Which is why behind the scenes Sony is trying to find some HDV answer to the the HD100. And, why Panasonic is bashing the HD100. Right now I believe both Sony and Pansonic are in panic mode. And, Canon must be a basket-case.

[Douglas Spotted Eagle]

Originally Posted by Steve Mullen

SO -- it is BS to say we should have skipped 720p. Even HDV is ONLY 72p30. So claiming we should have waited for 1080p60 -- which stil ain't even a legal spec AND will require every cable/DBS company cut their number of channels in half in nonsense.


The real slogan should be ONLY PROGRESSIVE VIDEO IS HIGH DEFINITION!.. 1080i should be called "high-resolution," but not HD. It is too plauged with artifacts to offer high DEFINITION.

All you need to do is watch sports on 1080i verses 720p. There is no comparision! 720p is pristine -- although slightly soft. But softer only in an A/B test. Nothing you would really notice.

Which is why I call the FX1/Z1HDV "under-sampled, high-resolution DV."

Oh c'mon, gimme a break! at the moment, interlaced is still the best acquisition format for anything with high motion. Sure, 1080p will be better, but we're not there yet, as you point out. But to suggest that interlaced is obsolete? I participated in Thomson (now Grass Valley) test shoots at a variety of framerates; progressive, and interlaced. Test subjects couldn't stand watching basketball acquired at 30p. It was terrible.

As far as the FX1/Z1, both are substantially better resolved cameras than the HD10U, which you have been a champion of. So is it that the JVC was great even though it was a lesser camera than the Z1, but now the Z1 sucks too because the JVC is coming?

I concur that progressive is a superior delivery format, but not everyone has flat panels just yet, and it's gonna be a while til we're there. Interlaced will be around for a long, long time. And by the time it's not, we'll have real 1080p, most likely. And that, is the grail for where we're currently headed. Surely you don't dispute that?

[Tommy James]

Well first of all even if Sony fired the representatives that spread the rumors that 720p is not real high definition. Even though Sony fired the CEO of the company to me that is a slap on the wrist and a small price to pay to gain a 90 percent HDV market share.

There is indeed evidance that the terms of the HDV consortium were violated by the refusal to acknowledge 720p as a real high definition format. Therefore the only remedy that can be obtained through a greivance procedure cannot be disciplanary action against Sony representatives but rather an expansion of the HDV specifications to allow higher resolutions like 1440i. JVC already has Sonys permision to do this because it was Sony that said 720p is not real high definition so if by upgrading 720p to 1440i JVC is only meeting Sonys demands so that 720p can can conform to real high definition specifications. So why not upconvert 720p to 1080p. Sony has indeed said that it is impossible to upgrade 720p to 1080p because scaling artifacts will be introduced and you will still not have true high definition. Don't get me wrong 720p converted to 1080p produces a very nice picture but it still cannot be considered true high definition coming from natively originated 1080i or 1080p. Most 1080i networks will not accept 720p cameras even if they can output 1080i by conversion because they will produce inferior results. But 720p networks will accept 1080i cameras because 1080p is the future so they allow conversions in the meantime.

Now if Sony can get away with upconverting its 1080i material to 1080p even though 1080p is not an official HDV specification. Why can't JVC owners upconvert 720p to 1440i even though 1440i is not a part of the official HDV specification?

So why doesn't JVC just produce a 1080i camera. The fact is that JVC cannot compete with Sony head on because Sony always has the reputation for quality. If the consumer had a choice between two 1080i televisions they would always buy the Sony over the JVC unless JVC lowered the price but that would further damage the JVC reputation of quality. But when JVC introduced the 1500i series of televisions back in 2003 JVC declared itself to be the aggressive competitor in the high definition television market by giving consumers an unprecedented level of quality.

JVC is also gained a lot of respect in Japan when they invented the HDV format with its introduction of the JVC GR-HD 1 single chip high defintion video with a color resolving power that exceded the limitations of the MPEG-2 codec. Rich psychadelic colors were produced which could not be surpassed without the use of higher bit rate codecs. And if that were not enough JVC introduced the HD-VHS format for the low cost distribution of high definition video that rivals Blu-Ray as being a legitamite low cost alternative and blew conventional DVD out of the water with its larger storage capacity and its high definition capability.

And if that were not enough JVC included ATSC tuners in its HD-VHS decks so that the poor consumer could watch for the first time real HDTV by decoding free off the air digital signals. Far too often the poor consumer spends thousands of dollars on an HD ready television only to watch crummy analog programing or standard definition DVD. JVC offers HD built in whether built into the television or built into its HD-VHS decks. Now if you think that HD-VHS decks are a failed format then so are off the air ATSC digital high definition recievers. It took an act of congress and the FCC to force television makers to include ATSC digital tuners in every television by the year 2007. Unfortunately there is no FCC mandate for the production of high definition VCRs so consumers thinking that DVD is high definition or thinking that VHS is inferior will stear clear of these high definition products further crippling the distribution of HDV content. And also since there is a format war going on between Blu-Ray And HD-DVD along with copyright infringement issues the consumer may take an apathetic approach to these products as well.

[Douglas Spotted Eagle]

I can assure you with all humor and sincerity, Sony's non-renewal of their CEO had absolutely nothing to do with HDV, or broadcast tools whatsoever. I'd be surprised if Stringham even knows the initials "HDV." You can bet your butt that Sony sells more consumer digital still cameras every day than they do HDV cams in a year. Broadcast/prosumer camcorders are such an insignificant part of the overall Sony Corporation that it's silly to even bring that into the discussion. You can also bet there is a lot more profit in 10 million CDs than there is in a year's worth of F900's, with a lot less hassle.

To bring us back to point:
Folks forget about the migration path to 1080p. When "legacy" HD
material needs to be up-rezzed to 1080 60p (it's just a matter of
time), what will look better, line-doubled 1080 60i material, or
heavily scaled 720p material? For that answer, I think all you have to
do is look at how nice 480i DVD material looks when it's line-doubled
with a modern DVD player and displayed on an HD monitor. Of course, the
some will always fall back to their buttressed position: "The
softer image gives it a film look!"

In closing, why even have this discussion in this particular forum? The camcorder isn't available, so it's just all circumspection. Sony will have their niche, JVC will have theirs, and Panny will have theirs. None will "kill" the other. Futuristically, it will all be 1080p at some point, and for some, it makes sense to work towards that now, and to others, it doesn't. But neither position negates any of the cameras coming on line.

[Barry Green]

Originally Posted by Douglas Spotted Eagle

Oh c'mon, gimme a break! at the moment, interlaced is still the best acquisition format for anything with high motion.

I'd say that the terminology could be cleared up here a little. High refresh rates are the best aquisition format for anything with high motion. Interlace is a lousy acquisition format, but 60i beats 30p for motion aquisition. However, 60i isn't as good as 60p; so I would modify the full statement to say: 30p is not a good format for high motion; 60i is better, but 60p is the best acquisition format for anything with high motion.

Test subjects couldn't stand watching basketball acquired at 30p. It was terrible.

I didn't see that test, but I have no doubt it's true. That's one of the big concerns I have about the HD100 -- no provision for recording 60p means that there will be several circumstances where it just won't be a viable option. Under those circumstances, I think the Sony would be the better choice, interlace or not.

But remember, progressive doesn't stop at 30p. 720/60p captures motion better than 1080/60i. You get 60 motion samples per second, but full frames with no interlacing artifacts. Motion is cleaner in 720/60p (and would be as clean, but higher definition, under an eventual 1080/60p). 720/60p is the highest motion sampling currently available, and ideal for sports, which is why the big sports channels Fox, ABC, and ESPN all chose 720p.

[Barry Green]

Originally Posted by Mark Grant

720 just isn't a big jump up over PAL... it's, what, 75% more pixels?

Actually it's almost six times as many pixels per second. A PAL frame is 720x576, but due to interlace pre-filtering you only really get about 720x432 of discernible resolution, at 25 frames per second = about 7.8 million pixels per second.

720p is 1280x720, every pixel completely discernible, at 50 full frames per second, = 46.1 million pixels per second. 46.1 / 7.8 = 5.91 times as many pixels.

The European Broadcast Union (EBU) has been doing extensive research into high def to make its formal recommendations about what format Europe will adopt for high-def. And they're almost unanimously choosing 720p.

[Douglas Spotted Eagle]

Of course you're right, Barry; I was sticking with the words being used. Interlacing has been heading to the dumpster for a long time now, but it will still be with us for a bit longer.

720p is obviously better for delivery, but still isn't the acquisition of choice, and that keeps coming back to my point. Acquire as much as you can, then remove/blend/process whatever you're gonna process at.

that said, 720p is only a stepping stone on the path to greater resolution and progressive images, which again, is what many folks seem to forget. How long will it be the better stepping stone? Probably not as long as I originally thought, based on the progress in our industry.

[Tommy James]

Again the argument that 1080i looks terrible on natively progressive displays is only true if the footage is not deinterlaced. The Sony HDV camera with its psuedo progressive CF30 modes of operation can produce footage that can fool many people into thinking that they are watching progressive footage. While the footage may not be as good as natively obtained progressive footage nevertheless the real high definition arguments offer a psychological advantage as the consumer thinks 1080p is better than 720p. Also footage may be deinterlaced in post further enhancing quality.

Also a new trend is that everyone of Sony's flat panel displays is being marketed as a Hi Scan 1080i HDTV. You see a 1280 x 720 flat panel display is only a 720p display but a 1365 x 768 flat panel display is suddenly a Hi-Scan 1080i HDTV and a 1920 x 1080 display is a 1080p television. Broadcasters like NBS CBS and PBS must be very happy that more televisions are now 1080i.

[Steven White]

720p is 1280x720, every pixel completely discernible, at 50 full frames per second, = 46.1 million pixels per second. 46.1 / 7.8 = 5.91 times as many pixels.

Saying nothing of acquisition format. I'm under the impression the only camcorder that records 720p60/50 is the Varicam, but it doesn't record 1280x720, only 960x720... which is 1.5x fewer pixels than the 5.91 you count - making the actual resolution of any 720p50 format 3.94 more pixels per second than PAL. Comparing with NTSC, the result is exactly 4x as many pixels per second at 60p. At 30p, exactly 2x the number of pixels. In 1080 land, the acquisition formats are 1440x1080 for HDCAM, and 1280x1080 for DVCPRO-HD, offering an even 4.5x and 4x NTSC respectively.

In short:
1920x1080(60i, 30p, 24p) = 6x NSTC
1280x720 (60p) = 5.33x NTSC
1440x1080 (60i, 30p) = 4.5x NTSC
1280x1080 (60i, 30p, 24p) = 4x NTSC
960x720 (60p) = 4x NTSC
1280x720 (30p, 24p) = 2.67x NTSC
960x720 (30p, 24p) = 2x NTSC

PAL = 1.2x NTSC if you want to adjust the numbers.

The argument that 1280x720p60 is "not high definition" doesn't hold water. As soon as 1920x1080i60 and 1280x720p60 are compared with a Kell factor, they are nearly identical... but this argument stops at high refresh rates. If you watch 720p60 content, and 1080i60 content and notice a significant difference in the perceived quality of the images - it is more likely due to compression and bandwidth sacrafices than the "definition" of the format.

Frankly, I don't see any flaw in a reduced-channel-1080p60 future. There's not a lot of good TV on anyway, and the vast majority of it is redundant. The current recipe for television is "qauntity over quality". I'd rather see it the other way around. 720p is a baby step. One that can be jumped IMO.

The other thing I'd like to see gone is pixel aspect ratios (PARs). PARs are fine for analog displays, but they don't scale well digitally. The sharpness obtained by having a digital interface to a digital display is awe-inspiring. Make 1920x1080 cameras and 1920x1080 displays. IMO scaling up is just as bad as interlace, if not worse.

-Steve

[Steve Mullen]

Originally Posted by Douglas Spotted Eagle

Oh c'mon, gimme a break! at the moment, interlaced is still the best acquisition format for anything with high motion. Sure, 1080p will be better, but we're not there yet, as you point out. But to suggest that interlaced is obsolete? I participated in Thomson (now Grass Valley) test shoots at a variety of framerates; progressive, and interlaced. Test subjects couldn't stand watching basketball acquired at 30p. It was terrible.?

So obviously, we can never shoot a 24fps movie about sports by your logic! Since we know sports are featured in movies all the time -- shot with a lower frame-rate than 720p30 -- your response is obviously simply incorrect.

What you saw was judder introduced by an incompetent cameraperson.

Moreover, JVC's Motion Filter will fix that problem so film experience is not needed. Post filter Motion Filter -- one will have effectively 1280x720 at 60fps. 60i can't touch 60p that for motion rendition because at display time 60i is reeally only 30fps.

Moreover, Z1/FX1 compositing/bgreen screen, and motion FX must deal with interlace motion artifacting, plus every vertical pan has line twitter.

Likewise there is no real detail in the Z1/FX1 because the CCD system undersamples 1440 by 50% and is offers only HALF what NHK assumed for the 10880i imaging system, e.g, 1920.

And, don't forget, that 25Mbps data-rate is essentially half JVC's 19Mbps -- leading to bit-starvation on rapid motion and that's why Panasonic is correctly bashing 1080i HDV. (You got to do math.)

So Sony's HDV "hi-rez DV" and not remotely what NHK had in mind. Even HDCAM is less than true 1080i. And NHK certainly didn't consider MPEG-1 compresed audio. With JVC we will get our PCM audio back.

It isn't that interlace is heading toward extinction, it is a "dead man walking."

[Steven Gotz]

Originally Posted by Steve Mullen

It isn't that interlace is heading toward extinction, it is a "dead man walking."

That is just about a given. But when? Is the new JVC the answer? Probably not exactly. I would still like to have an affordable 1080p, but that might not be any time real soon.

So I make do with the FX1. It does produce some nice video. I don't see any competition in the $3K range any time real soon. But I really don't see a reason for interlaced anymore. The technology just isn't necessary.

[Douglas Spotted Eagle]

"So obviously, we can never shoot a 24fps movie about sports by your logic! Since we know sports are featured in movies all the time -- shot with a lower frame-rate than 720p30 -- your response is obviously simply incorrect.

What you saw was judder introduced by an incompetent cameraperson."

No, what I saw was temporal delay. The cameraperson(s) were all reasonably well known guys that shoot NBA every week. Easy to target them because they're supposedly the variable.

Given 60 opportunities to capture motion vs 30 opportunties to capture motion, even a child can figure out which frames contain more AT ACQUISITION. Not talking delivery here.

Re: film; you don't see "sports films" that are shot like dramas, documentaries, or live events on film. It's not even a reasonable comparison, nor a participant in the discussion. If home viewers were subject to watching sports at 24p or 30p complete with pan shots of balls in the air, you'd have a bunch of sick viewers, because it affects their eye timing. It's not just a theory, it's a fact. There is too much time between frames for movement to occur and it's simply not natural.

Whats interesting is that while we're on a topic of technology, you're trying to sell me a JVC camera or telling me why Sony cameras are bad. So JVC's brand of "Hi Rez-DV" is better because it has PCM audio? You're suggesting that Mpeg1 Layer II audio is bad? This is one easily quantified, and something I've tested extensively. Please, I'd like to see (or rather hear) evidence of where the MPEG 1 audio has failed you. (or anyone) I didn't realize we were moving towards a discussion of JVC vs Sony, and I can't have that discussion intelligently, as JVC hasn't delivered the camera yet; my 20 minutes on the NAB floor with the camera don't qualify me as an expert on the JVC cam. But just because it's PCM audio doesn't automatically make it better. There are other, substantially more significant variables related to the quality of the audio, either from the mic or from mic input.

[Steven White]

at display time 60i is really only 30fps

At display time, when properly displayed, 60i is exactly that: 60i. It isn't 30fps, it's 60 fields per second, each field separated by 1/60th of a second. We all know this. Properly displayed 60i should either be scanned by CRT, or on a progessive display deinterlaced and upsampled to 60p.

(You got to do math.)

Okay, I'll do the HDV math. 1080i HDV has 1.5x as many pixels as 720p HDV (per unit time), but it also has 1.31x the data rate, in addition to a much longer GOP. Without taking the GOP into account, 1080i HDV is 14% more compressed than 720p HDV... assuming all 19 Mbps and all 25 Mbps are devoted to video. If the "ProHD" 24p format does in fact use all 25 Mbps, then you can argue that HDV is 50% more compressed, again, saying nothing of how GOP affects the efficiency of the codec, and subsequently the comparison of the images.

The biggest problem with 1080i HDV is how the interlace and colour sampling buggers essentially progressive images. If they ever make a 1080p HDV cam, they better make damn sure the camera encodes the image with progressive flags.

Will the JVC HD100 produce better quality images than the FX1? It had better... it costs a lot more. With the new HD camera releases, I can see Z1U sales slipping to the JVC in certain situations - and in order to get the Panasonic camera running as anything more than a miniDV camera, you need to spend nearly double the price of the Z1U/HD100 and triple the price of the FX1.

-Steve