My thought - 1080i is dying
 

I was playing around a little the other day, and I tried some experiments with progressive and interlaced video. Without going into detail, I had no trouble deciding that progressive video really needs to be seen on a progressive display, and interlaced on an interlaced display. If you convert, you give up the advantage of either. And they each DO have their unique advantage.

The problem is, the only really good interlaced display is the CRT. The glow of the phosphors decays, so that the two fields look like motion, not a single image divided into skewed horizontal stripes. I once saw a still frame of a spinning top that had not been de-interlaced. It just sat there spinning forever! This was several years ago, obviously on an interlaced CRT. A progressive image is also degraded when seen on an interlaced display. Are you with me so far? In a nutshell - either format loses its advantage when it must be converted to the other!

Now comes the rub! What kind of monitor (TV?) will be showing tomorrows pictures? A recent trip to Best Buy yielded a grand total of TWO CRT rear projection sets. About twenty other models were LCD, DLP, or D-ILA. There were a couple other isles with a variety of plasmas and back-lit LCDs. There were a couple monster CRTs of the 35 or so inch variety. What's left? A bunch of SD CRTs of varying sizes. There was still a pretty good variety, and they were CHEAP. How many CRT sets will be sold five years from now?

NOTHING has shown up yet in the store to display 1080i native - except for the CRTs. I have yet to see a CONSUMER CRT that looked sharper than the variety of 720 x 1280 sets. And contrast ratios, colorimetry, and SDE are getting better all the time.

So where will all this super video be seen? Probably only on the commercial grade monitor at the production facility.

Keep in mind too that broadcasters, cable and satellite companies will all be frugal in allocating their spectrum. 1080p30 might have a chance, and 1080p60 could make it to HD disc - but then where would it bee seen?

I see the CRT dying in a few years - and with it 1080i.

I'm sure there are those who disagree with me - that's why we call it a forum. Have at me!

1080i shows and other programs are hatching lot fater than 720p's. After 1080i's die, what will replace them? 1080p. You imply that 720p's will not be dying with 1080i's? They will be awfuly lonely in 1080 world.

Future sets will be 1080p. I seriously doubt that programs upconverted from 720p will look better on them than programs upconverted from 1080i.

35,000 1080i HDV cameras were sold. How many 720p HDV cameras were sold so far?

Radek

"Future sets will be 1080p. I seriously doubt that programs upconverted from 720p will look better on them than programs upconverted from 1080i."


Actually vertical detail would be better coming from 720p instead of 1080i if you are going to 1080p. Depending on how the 1080i is interlaced you would only really get 540p for vertical detail.

As for horizontal detail well the Varicam shoots it's 1080p at only 1280x1080 so 1280 horizontal pixels could give a very nice image. This is even more so considering most 1080i cameras are not giving 1920x1080 but only 1440x1080.

Take all of that and in the best case you could get 1440x540p from a 1080i source. The 1280x720 actually has roughly 19% more raw pixels. Also take into consideration that de-interlacing can give you aliasing artifacts in an image which can be more obvious than just having a softer image from scaling up.

About the only real advantage to current 1080i HDV is we do get a little bit more chroma detail. With 1280x720p the chroma channels are only 640x360. 1440x1080i has 720x540 chroma channels. The other advantage is that with 1080i all of the scaling and de-interlacing is done before compression. 720p will be scaled after compression.


"35,000 1080i HDV cameras were sold. How many 720p HDV cameras were sold so far?"


I think this may change soon with other 720p HD cameras coming out soon. Since SONY is the only really decent prosumer HD camera out there right now you cannot really use this as a point. When Panasonic and JVC, and anybody else come out with their cameras they will be 720p (mostly?) This time next year 720p gear could way outsell 1080i gear.



Now if and when we do get 1080p cameras and TV's well this debate won't happen anymore.

Not true at all. In the best case you get 1440x1080 on a completely static frame. In the _WORST_ case you get 1440x540 on a frame full of motion, but then you probably won't even notice since it's likely to be blurry as hell anyway.

In the average case, with any kind of smart deinterlacing you're likely to get a picture at least as good as 720p when you convert from 1080i to 1080p... and with more horizontal resolution.

>>>Actually vertical detail would be better coming from 720p instead of 1080i if you are going to 1080p. Depending on how the 1080i is interlaced you would only really get 540p for vertical detail.

You're converting to 60p. You'll get lot more.

>>As for horizontal detail well the Varicam shoots it's 1080p at only 1280x1080 so 1280 horizontal pixels could give a very nice image. This is even more so considering most 1080i cameras are not giving 1920x1080 but only 1440x1080.

Varicam shoots 720p at 960x720 pixels.

>>Take all of that and in the best case you could get 1440x540p from a 1080i source. The 1280x720 actually has roughly 19% more raw pixels. Also take into consideration that de-interlacing can give you aliasing artifacts in an image which can be more obvious than just having a softer image from scaling up.

This not correct.

Ok then find me a camera that actually does smart de-interlacing. The whole point of this topic was hardware and not software. Yes you can use a smart de-interlacer in software but any slight movement will need to be de-interlaced. If you had a ball slowly moving across the screen 3 pixels at a time it would be interlaced. That ball would also be pretty sharp since it is moving very slow. It all depends on what you shoot. Even the slightest movement of the camera will cause the image to be interlaced.

Most people will not be using a HD camera to be shooting perfectly still scenes. I am talking about real world usage of a 1080i camera. If you handhold that camera I don't care how sturdy you think you are every single part of every single frame will be made up of interlaced lines. Any very slow pans would also be 100% de-interlaced but still very sharp. Yes if you shoot pretty much still frames you would have a true 1440x1080 image but that actually happens much less than you think.

If we depend on a camera or TV to convert our 1080i footage into 1080p chances are that it will be a simple de-interlace conversion. That is why I said in a best case you may only really get 1440x540p. Yes in software on certain shots you may get better but we are talking about consumer hardware here.

It is also a question with the FX1/Z1 if we even get 1440x1080. Since the chips are only 960x1080 but use pixel shift I decided to test this out. Even though there is a little bit more detail than if it was only 960x1080 it isn't really 1440 either. It is really somewhere in between making it even closer to 1280. Heck if pixel shift worked that well SD cameras could get by with chips that only had 1/2 the amount of pixels.

The Panasonic DVCpro HD format has two specs for 720p and 1080p/i. 720p is 960x720. The 1080 format is 1280x1080. The newer Panasonic Varicam as well as the new handheld Panasonic HD camera use both of the DVCpro HD specs. The older camera only does 720p.

Now don't get me wrong here. I'm not really more for one format or the other. I'm just letting you guys know what I have been finding out with a lot of complex image tests.

What I have been finding out is that at the end of the day it is pretty hard to tell the difference between 720p and 1080i on a HDTV. Certain types of HDTV's may have a slight edge for a certain format but it is very very far from a night and day situation.

Eventually when HDTV's and cameras can do 1080p we will not need this debate anymore. Clearly 1080p would be better than 720p. Would you try to say that 1080i is as good as 1080p? Clearly it isn't or nobody would care about 1080p. The issue at that point in time would then be what old footage will look better on a 1080p display? 720p or 1080i. I think they can both look good if done right.

Yes, but who in their right mind would do that? If you want to get 1080p footage out of a 1080i source, you'll be doing it in software after you edit.

You seem to be deliberately going out of your way to find artificial conditions in which 1080i would look its worst, and then complaining that it's worse than 720p at its best.

Edit: I'd also add that, since I don't have an HDTV, I watch all my HD footage on my PC monitor, which is effectively 1080p. The software doesn't deinterlace the footage, it displays 540p at 50fps with 2x scaling, which is the other alternative for 1080i on a progressive display and doesn't introduce nasty motion artifacts since you see all 50 fields.

I agree. And my take is that neither format is "dying," in fact both are flourishing and will continue to do so. Each will have its detractors and proponents, but the bottom line is that with slight differences between how the images are presented and how motion and color are handled, both end up being about equal in an overall sense.

I am not going out of my way to do anything.

This whole thread was started based on watching HD footage on HDTV's and how the two HD formats will look and if the market will support both.

I even ended by saying that really both are pretty much the same. All I ever pointed out is that with standard de-interlacing done with hardware and some software the best you could really have is 1440x540 detail. I never knocked one format or the other. Did I ever say 540 would look like garbage? I just gave the numbers and you are coming to your own conclusions based on what I said. I gave facts. You are giving opinions that it looks good. I agree it does look good. At the end of the day however de-interlacing 1080i or scaling up 540p will give you the same interpolated results.

I gave my information on what I know about 720p vs 1080i to help figure out where the market could be going in terms of HDTV's. This debate is starting to turn way too political to be worth it anymore. You have the 720p people and the 1080i people. As soon as somebody tries to compare the two, somebody gets upset and starts treating them like they are a moron.

As to who would want to use hardware to convert their video. Well anybody. When ever you plug your camera into a 720p HDTV it is getting converted. We are talking about hooking up gear and watching on a TV here. Not processing footage in a computer.

The most primitive deinterlacer is line doubler, after discarding every other field. I own FX1E and can tell you you get lot higher resolution, even on movement, in CF25 than with 540 lines scan. So even inferior hardware deinterlacer is lot more than is being discussed here.

Radek

P.S.

Varicam records 720p, never 1080i.

http://catalog2.panasonic.com/webapp...Model=AK-HC930


Ok it isn't the Varicam but it is the newer Panasonic HD camera. The point I was getting at is the HD format for Panasonic DVCpro100 HD not so much the camera. Look at the DVCpro HD codec in Final Cut Pro and you will see it has 720p and 1080i. Any camera that uses DVCpro HD will use the 1280 x 1080i format.

Not necessarily. The VariCam has no access to the 1080i version of DVCPRO-HD.

The codec and the recording format support both 1080i and 720p. However, the individual cameras built to use the format do not. The VariCam uses only 720p; the HDX400 uses only 1080i.

The new HVX200 will be the first DVCPRO-HD camera that supports both 720p and 1080i (and 1080p carried within a 1080i stream).

The camera signals Panasonic will deliver 1080p even on larger cameras. They mentioned at NAB they can use the 10 bit D5 format with MPEG4 encoder to deliver super quality 1080p camera. It's about time.

Radek

Sorry Barry. I meant any 1080 Panasonic camera.

Supposedly the next generation of f900's will be able to resolve 1080 60p which should nicely integrate the features you were talking about. I think however it's difficult to say that it's the death of one format or another when most people don't have either. The original problem with 1080p format was broadcast issues. I believe that most of the stations that are going up to HDTV will not switch their signals again in the near future. Expecially with the agreed upon specs from the ITU and SMPTE.