Anyone done FX1/ Z1u 60i hdv to 24p files?

[Graeme Nattress]

1080i60 converted to 720p24 looks very close to real 720p24. 1080i only has around the same vertical rez as 720p anyway due to interlace filtering, so it's never going to look as good as 1080p24.

Native 24p is always going to look better than converted 24p, and looking at the footage I have from Varicam 720p24 DVCproHD, JVC HD100 720p24 and my conversions, I'd rate them like this:

1) 720p24 From the Varicam. The luma is slightly better in terms of less compression artifacting than the 720p24 HDV, but the chroma is way nicer. The slightly lower resolution is invisible in terms of percieved detail, probably because it's super-sampled from a higher rez CCD, and that the lens on the HD100 is a limiting factor, along with the compression.

2) 720p24 from JVC HD100. Very nice 24p, looks less compressed than other HDV footage I have. Has more of a real high definition feel than the Sony HDV in that the detail is much finer in relation to picture size.

3) 720p24 converted from 1080i60 from the Sony HDV. Reducing the frame size on this footage helps a lot. It looks better, to me, than the native footage, and on sympathetic material, looks very close to 2) and to 1) above, but is noisier.

720p24 HDV at 19mbps compared to 720p24 DVCproHD at 40mbps is a very interesting comparison. Normally you'd expect about a 2.5 times advantage for MPEG2 over a DV type codec, giving HDV an euivalence of about 47mbps, but there are too many differences between the codecs to make that simple comparison totally valid. We have HDV with a slightly higher resolution, but lower chroma sampling. DVVproHD has slightly lower resolution, but higher chroma sampling. Looking at the real world images I have, the DVCproHD stuff looks better in terms of less compression artifacting, but it's very close, but I much prefer the DVCproHD 1080i footage I have, which, to me, looks better still!

It's very hard to compare HDCAM to HDV. The only footage I have from HDCAM is from a project I did with Panavision, and they shot some green screen footage for me. This footage I have is from HDCAM tape, but I have it uncompressed on my system, and it looks very much better than any HDV I've seen, but obviously, it was recorded on a HDCAM camera with the nice Panavision lenses, and that's not fair to HDV as the Sony HDV camera really looks lens (and CCD for that matter) limited to me.

Graeme

[Peter Moore]

"The motion may appear ok to your eyes, but you are creating a mess with the frames"

As I said,

"which only the most discerning eyes would know was artificial."

You can look at a still frame and say it's a mess, but look at it in motion and it's damn good.

At any rate, convert to 60p first, to 120p first, whatever. Bottom line there is no method that will give you 24p without blending fields because

FIELDS HAPPEN AT DIFFERENT POINTS IN TIME

You can convert to 60p by doing the following:

A1 + A2 *
A2 + B1
B1 + B2 *
B2 + C1
C1 + C2
C2 + D1 *
D1 + D2
D2 + E1 *
E1 + E2
E2 + A1

And then take the starred frames (inverse telecine) and get the same thing. But, again you still need to blur fields.

How you would convert to 120p from 60i I have no idea.

[Thomas Smet]

Graeme,

This is an interesting point that hopefully we will find out once all of the other cameras are out and we can compare. Due to lens and actually pixel count from the chips is there really going to be a quality change from a nice 720p to 1080i? I have been debating this with myself (no I'm not crazy) for a long time. I have tried doing test with 3D rendered images but that just doesn't help because it doesn't factor in lens and chip quality.

Even though there are ways out there of trying to get a high quality conversion from 1080i to 1080p do all of us really want to mess around with that much rendering when 720p shooters will be ready to go the moment they capture the footage. Workflow will become a huge factor when the playing field levels out.

I just read the article on the FX1 on the updated HDVinfo website and it was mentioned how shocked that the author and other people at the shoot didn't really see any resolution difference between the FX1 and a DVX100A when watching on many different HD displays. I found this to be a little shocking and not 100% sure if I agree with that. To be fair however the author was shooting in CF24 which we know kills the horizontal resolution.

Perhaps when the JVC camera comes out in a few months we will finally get to test this debate. I'm really hoping the lens options on the JVC will open up a whole new level of quality for HD even if it is only at 720p. The only thing I hate about 720p HDV is it's limit of only up to 30p. This kind of limits the camera in the broadcast market where a 1080i camera will at least have the same look motion wise as a high end camera. They have their motion thing but I haven't seen it yet. Will it be good enough for broadcast? I can see broadcasters easily rejecting 720p 30p footage where with 1080i dumping to HDCAM tape they might not be able to tell.

I guess we will have to wait a few months to really find out.

[Thomas Smet]

Graeme,

Since you are one of the only people to have seen footage from the new JVC camera and I know you know your image quality I take your word for it.

In your opinion do you think using uncompressed live from the JVC would look pretty damn good then?

I am actually one of the nut jobs that will be getting an uncompressed HD system in a few months. Right now I am leaning towards a Multibridge with 12 bit HD component input.

[Graeme Nattress]

If you go out of the component outputs of the JVC and record uncompressed, I think it would look really good indeed, but at that point, you're also really limited by the lens, and a top end HD lens doesn't come cheap. Compression hides a multitude of sins..... The major thing I see in the JVC footage is the compression - the image itself looks pretty good. Take away that compression and you might be able to see other things wrong with it, that the compression would otherwise hide, but that's mostly conjecture at this point, as although the uncompressed analogue component output looked nice at NAB, I'd hardly call their setup as suitable for critical viewing comparisons.

I don't know enough about the noise levels on the JVC to know if capturing in >8bit will make any real world difference though.

Graeme

[Thomas Smet]

Just thought about one advantage of shooting and recording 1080i and converting to 720p.

This would be the only real way of getting 720p 60p from tape on a HDV camera. All 720p HDV cameras are limited to recording 30p. With 1080i you basically have 60 frames that are 1440x540 that will be of the same quality as a deinterlaced 1080i frame. You can now convert and actually get a pretty good 720p 60p this way.

Of course this conversion would require editing in an uncompressed format so you might as well just capture 60p live from a camera or edit as DVCpro HD.

[Boyd Ostroff]

Originally Posted by Thomas Smet

I just read the article on the FX1 on the updated HDVinfo website and it was mentioned how shocked that the author and other people at the shoot didn't really see any resolution difference between the FX1 and a DVX100A when watching on many different HD displays.

Maybe we read different articles? Are you talking about Jon Fordham's FX-1 review? http://hdvinfo.net/articles/sonyhdrfx1/fordham9.php

If so, it didn't say the "author and other people" were "shocked" while watching the footage on "many different HD displays." Instead, Jon describes his experience watching dailies on a 34" consumer HDTV with the script supervisor.

When I switched back and forth between the FX1 and DVX100A while she watched the monitor, she said she could see a difference. But that neither one looked better than the other. They just looked different. The fact that FX1 didn't look any better to her was something for me to consider.

[Thomas Smet]

Sorry. Shocked may have been more of what I was thinking about what was said in the article. It was too strong of a word but I didn't want to quote the article exactly. I meant there was "Something to consider" and "kept thinking about it" about the fact that some people couldn't really see any extra detail. I'm sure in some way the shooter may have been a little shocked based on the fact they were comparing SD to HD.

You are right though that on a 34" HDTV it would be harder to tell.

Never once did the author actually say if he agreed with the other person or not. He just said he kept thinking about it and considering it. Does that mean he agrees?

Maybe I should have perplexed instead.

[Radek Svoboda]

Originally Posted by Graeme Nattress

1080i60 converted to 720p24 looks very close to real 720p24.

recorded on a HDCAM camera with the nice Panavision lenses, and that's not fair to HDV as the Sony HDV camera really looks lens (and CCD for that matter) limited to me. Graeme

Greame,

Thanks a lot. That is so much useful information from someone who is expert.

So actually if Sony comes with decent HDV camera with native resolution chips and interchangable lenses, we may have basically same quality as HD100, if understand right.

As it stands now, all 3 cameras create decent 720p product, superior to SD. Is right?

Sony has further advantage offering auto focus, 60i, which is what U.S. networks want. Want 1080i60 or 720p60. Smoothing of 30p on HD100 will mean longer open shutter, less sharp images, or similar effect.

Sony offers this quality in FX1E for 3,000 USD, now even HC1 for 1,800 USD, with worse low light performance. JVC is only slightly better than Sony HDV converted to 720p, will probably cost 2x as FX1 and 3x as as HC1.

Add price into eqation, 60 Hz, auto-focus. Sony immediately strike as super buys in 720p progressive environment.

Further, you can create 720p60 from 1080i60, as Thomas mentioned, giving Sony further advantage having slow motion capability.

As recording uncompressed, that's too complicated and expensive and time, manpower consuming.

Radek

[Graeme Nattress]

"So actually if Sony comes with decent HDV camera with native resolution chips and interchangable lenses, we may have basically same quality as HD100, if understand right."

Native rez chips will do a few things:

1) require higher quality lenses
2) produce more noise
3) have less dynamic range

Unless they make the chips a lot bigger. At that point, it's called HDCAM and costs a fortune.

I do agree that limiting HDV 720p to only 30fps is a bit limitation. 720p60 should be the format, but you'd need to double your data rate (not quite double, but for a rough guess it's ok) to keep the quality the same.

1080i might be flavour of the month, but progressive video will be the future king, and we won't ever go back to interlace. Interlace is just compression, and pretty poor compression compared to what can be done digitally these days.

Graeme

[Nigel Traill]

Graeme,

thanks for all the information - really valuable - I have a question that perhaps needs a new thread - about going from progressive to interelaced... but while you're here... what about going from 720p to 1080i?

The HD100 camera and deck are able to output 1080i.

What are the image issues with this process?

Have you converted HDV 720P to 1080i using your own products, and is there a need for a third-party product, or will the JVC conversion options be as good as it gets?

thanks in advance,

Nigel

Anyone who has any thoughts or experience - I'd be very grateful to hear from you.... Cheers.


[QUOTE=Graeme Nattress]

1080i might be flavour of the month, but progressive video will be the future king, and we won't ever go back to interlace. Interlace is just compression, and pretty poor compression compared to what can be done digitally these days.

[Graeme Nattress]

I must admit I've not done any 720p to 1080i conversions.

If you're doing 720p30, you'd just map frame for frame, so you'd end up with 1080p, but in a 1080i video. Because you've scaled up, you'd think that it would look soft, but 1080i has to be soft to stop interlace twitter, so in real 1080i you might have a higher horizontal rez, but in practical terms, I don't think you'll see much difference if the scaling up is of high quality.

For 720p60, you'd again scale up frame for frame to get 1080p60, then compress two frames into two fields to go to 1080i60. This should look very good indeed as again, the interlace and it's necessary filtering will give the 720p room to be blown up a bit without looking bad.

The only thing that's really going to improve things is scaling algorithms, and that's something I've been working on for quite a while now, as it seems that it's possible to do quite a bit better than standard and even exceptional video hardware manages.

Graeme

[Thomas Smet]

Actually the Multibridge wouldn't be that bad with Final Cut pro. What I plan to do for most things is actually run component in and capture directly to DVCpro HD or photo jpeg. This gets rid of the need to have massive hard drives but gives higher quality than using HDV. With photo jpeg you can get full HD resolution at 4:2:2 for around 30 MB/s which should work even on a single drive system. The Multibridge on a PC cannot capture to a compressed HD codec yet.

The other option is a Cineform Aspect system that captures directly to their cineform HD codec which would also only be around the datarate of DVCPro HD. This option costs a lot more than the decklink route but may give higher quality.

For the problem of 720p 30p only We could always try to interpolate the in between frames to make a 60p for broadcast. This would only have to be done after the final edit. If a really nice tool is used that actually creates new frames nobody may even notice. It would be really hard to see an interpolated frame every other frame 60 times within a second. Even if the in between frames were blended it might be enough to fool a lot of people.

Does anybody know if there are actually any broadcasts in 720p 24p? How does the pulldown work for 24p material on a 60p display device? What do 24p DVD's do on a 60p display device?

[Kyle Edwards]

Originally Posted by Thomas Smet

Does anybody know if there are actually any broadcasts in 720p 24p? How does the pulldown work for 24p material on a 60p display device? What do 24p DVD's do on a 60p display device?

Aren't the TVs that support 60p also support other framerates/resolutions?

Originally Posted by Peter Moore

Your post

If you can live with the problem and be content with the results, go for it.

[Radek Svoboda]

Interlaced will be gone one day but what will replace it will be 1080p60.

After European HDTV organization decided make 720p50 standard for Europe, Sony pulled it's muscle, three things happened:
The commission retracted decision.
Sony started push for future 1080p50-60 HDTV, MPEG4, Part 10 based.
Sony introduced superb low cost 1080i HDTV cameras. FX/Z1 supposedly sold about 150,000 units by now worldwide. If that is correect/not I don't know, but new Sony HDV cameras sell at many times rate than PD150 was when was introduced.

Sony basically developed 1080i60 analog HDTV in Japan, later 1080i60 digital. They did with NHK. They very powerful in broadcast world, are able to push their technologies. They also very capable. Throughout their history they were able make better, smaller products than competition, in the past did not even care what competition is doing. Competition just gave up competing with Sony on new formats etc. When Panasonic developed M2 for broadcast, Sony just developed better format, M2 became history. I think we will see same thing in JVC HDV vs. Sony HDV. Can also see different marketing strategy compared lets say Panasonic, when their people get on these boards. Sony people are prohibited to do. They just make superb product, like XDCAM, HDCAM, Z1, let owners discuss advantages on these boards.

Lately Sony were mismanaged though, their movie division prevented electronics division produce avantguard products that would harm movie business, due concern about copy protection, etc.

Another advantage Sony has, make the best sensors. Have 75% of worldwide CCD market, are only company capable produce in quantity high quality CMOS with high frame rate at high pixel count, high S/N ratio. JVC normally use Matsushita CCDs, their top broadcast products use Sony CCDs. Nikon use Sony CMOS, top photography manufacturers use Sony CCDs.

HDTV and FILMOUT:

For broadcast 1080i has advantage because except some US 720p broadcast, is only 1080i HDTV broadcast anywhere in world, including two satellite programs in Europe.

When do film transfer, optical printers are 2K. 1080p is 2K, wheras 720p is 1K. So question is, if equal quality sensors and high quality lewnses used, would 720p24 HDV or DVCPRO HD look better when transferd to 2K than 1080i HDV transferd to 2K?

Digital projection in theaters - 2K. Future will be likely 4K, as new Sony projectors are 4K = about 8MP.

24p on a home screen:

1080p24 is part of HDTV spec, as far I know all 1080 broadcast is 50-60i and 24p is broadcast with pulldown.

24p does not look good on CRT, maybe not even LCD. 30p on screen has more of theater 24p feel than 24p does. In theters each frame projected twice, otherwise motion is jerky at 24, at stimulated 48 fps is better.

24 fps is rate that dates when sound film started in 1929, while video people always wanted 24p, top film directors wanted highest frame rate they could. Top 70 mm film productions were 30 fps, with 24 fps 35 mm cameras running side by side for to create 35 mm prints.

IMAX HD is 48 fps.

Some manufacturers catering to 24p hysteria, taking advantage of it, calling it "film look". Best film look something totally different. 24 fps and grain are negatives, not positives about film look.

DVCPROHD:

DVCPRO HD compressed about 7:1. It's just too compressed.

PROSPECT HD:

This superb 10 bit compression software now available saparately and bargain OEM price negotiateed could be with CineForm.

Radek