For those familiar with AviSynth, here's a simple 1080i60 to 720p60 avs script to play with:

AVIsource("02.avi")
assumetff
tdeint(mode=1)
#use mode=0 for 30P or mode=1 for 60P
lanczos4resize(1280, 720)

There are better deinterlacers, like McBob, but I find TDeint to be a good tradeoff between quality and speed. It's downloadable here: http://bengal.missouri.edu/~kes25c/TDeintv11.zip

For those familiar with AviSynth, here's a simple 1080i60 to 720p60 avs script to play with:

AVIsource("02.avi")
assumetff
tdeint(mode=1)
#use mode=0 for 30P or mode=1 for 60P
lanczos4resize(1280, 720)

There are better deinterlacers, like McBob, but I find TDeint to be a good tradeoff between quality and speed. It's downloadable here: http://bengal.missouri.edu/~kes25c/TDeintv11.zip

Wow! What good timing. I just tried the same thing, but using Avidemux2. The deinterlacer I found to work the best was DGBob, which is motion compensated and can double the frame rate. Here was the filter stack for Avidemux2 that I used:

1. Deinterlace - DGBob with threshold 12 and frame rate doubling
2. mPlayer resize to 1280x720 with lanczos interpolation
3. mSharpen with strength of 70 and threshold of 15

The small amount of USM (step 3) was to add a small amount of EE as pre-compensation so that edges are preserved a little better on upsampling to 1920x1080. After upsampling, the EE is no longer visible but the edges are sharper.

I was surprised how well it worked. the DGBob deinterlacer worked well, the resulting 60 fps frame rate gives smooth playback even on a PC, and the little bit of EE caused the edges to stay fairly sharp even after upsampling.

This type of video can be distributed on BD, and might look better than 1080/60i or 1080/30PsF on lower end TV's that don't interlace well.

I think what this brings to the argument is that although nobody here is 100% sure at the moment, it is at least possible that *some* TV's *may* be doing interlacing in such a way that they generate 60 fps frames from some combination of bobbing, scaling and weaving the fields.

Dave, you can include playback devices in that category too, as well as AVR's. This is all a very complicated mess that unfortunately the consumer now has to deal with because poor decisions were made in the past. It's really too bad that you either have to become an expert on practically every CE subject today, or find an authoritative review before buying just about any piece of gear now.

The variations that you speak of are likely the result of proprietary video processing algorithms employed by the various chipset manufacturers in an attempt to differentiate their products from one another. And that's a good thing; but the flipside is it creates this vast "unknown" regarding your distributed project if you try to chart virgin territory.

I will continue to bug these manufacturers and try to get answers to these de-interlacing questions WRT their video processors and the implementation of those processors in certain key A/V components. Any info I get from them will be added to this thread...

Dave, you can include playback devices in that category too, as well as AVR's. This is all a very complicated mess that unfortunately the consumer now has to deal with because poor decisions were made in the past. It's really too bad that you either have to become an expert on practically every CE subject today, or find an authoritative review before buying just about any piece of gear now.

Yes, this is why I haven't bought a TV yet. Obviously I'd like to get one that does a good job of deinterlacing both 24P 2:3 and 60i (perhaps even generating a good quality 60P stream from the 60i), but even though I'm a technical person and have some idea of what is technically possible, it's so hard to actually find out what products actually do what, and I don't have 8 hrs. a day do devote to research.

Having said that, there seems to be more standardization in how the camcorders behave, e.g., they all generate 1080/60i in more or less the same way (ignoring details like rolling vs. global shutter), and some can generate 24P in 60i and 30P in 60i. So I'm thinking the correct order is to first get a camcorder, then take the camcorder with you and view the video on the different TVs. You can't determine everything this way, such as how the TV handles true 24P or true 30P, but you can at least compare how well they deal with interlacing.

I suppose the good news is that even though interlacing is not going away any time soon, the processor chipsets are getting better and in a year or two most TV's will be able to deal with it (and 30PsF) much better.

Hopefully you'll hear something back from the chipset makers ;-)

I was told that in a choice between 60i and 24p, use 24p for more professional looking work. It's less clear whether one should use 30p or 24p, but as for the effects, 30p will produce a nice, clear, progressive image that produces less motion blur than the 24p recording would, without interlacing.

So, I'd say use 30p if you have it, and if you don't, 24p if you're shooting on a tripod and know to make slow, fluid movements, 60i if the subject's more unpredictable or you're operating handheld.

Yes, this is why I haven't bought a TV yet. Obviously I'd like to get one that does a good job of deinterlacing both 24P 2:3 and 60i (perhaps even generating a good quality 60P stream from the 60i), but even though I'm a technical person and have some idea of what is technically possible, it's so hard to actually find out what products actually do what, and I don't have 8 hrs. a day do devote to research.



Actually picking the best TV is one of the easier jobs today. Every review has called the latest generation of Pioneer Kuro displays the 'best ever'. Seldom have I ever seen such universal praise for any AV product.

Owning two, I can attest to their unbelievable picture quality. And yes, they perfectly deinterlace, but you do get some motion jitter with 30p in a 60i stream. I don't believe any display will show buttery smooth motion from this 'wrapper'. However, you do get buttery smooth motion from every other source I've ever fed it. The Pioneers have something called "smooth" processing which even helps smooth out motion judder inherent in some 24p BR discs. It's almost weird to see such smooth playback of scenes you know contains this judder. That processing can be engaged or disengaged, your choice.

Highly recommended!

Actually picking the best TV is one of the easier jobs today. Every review has called the latest generation of Pioneer Kuro displays the 'best ever'. Seldom have I ever seen such universal praise for any AV product.

Owning two, I can attest to their unbelievable picture quality. And yes, they perfectly deinterlace, but you do get some motion jitter with 30p in a 60i stream. I don't believe any display will show buttery smooth motion from this 'wrapper'. However, you do get buttery smooth motion from every other source I've ever fed it. The Pioneers have something called "smooth" processing which even helps smooth out motion judder inherent in some 24p BR discs. It's almost weird to see such smooth playback of scenes you know contains this judder. That processing can be engaged or disengaged, your choice.

Highly recommended!

Thanks, Ken. Yes, the Kuros come highly recommended from a number of sources, so in that sense I guess it's an easy choice. But they are also near the top of the heap price-wise. I know you get what you pay for, but I was hoping to find something more mid-priced that still had decent signal processing performance. The new crop of Panasonics due out soon are rumored to have improved signal processing and might be more mid-priced, so I may wait a bit and check them out.

I might end up wanting a Kuro, but I will have to build up some courage before trying to get a $5,000 TV past the finance committee ;-)

Yeah Dave, generally that 'finance committee' demands something in return. That can be a very expensive proposition! ;)

60i is only yielding 30 real fps, as captured by the camcorder, any way you cut it on a progressive display.


Aaron, why do you state that as if it were an established fact? It hasn't been proven by the discussion and links in this thread. In fact, at least 2 of the linked articles have mentioned deinterlacing methods for 1080i that yield 60fps output.

Consider, for example, the digitalcontentproducer article. The descriptions given for the "Bob" and "2D FIR" methods specifically say that frames are output each field time, i.e. 60fps. Those methods by themselves don't seem very desirable, but how about this one:

"A Vector Adaptive interpolator uses memory to hold four fields. Logic measures motion between fields. For static video, weave is employed. For dynamic video, samples come from the current plus a previous and/or a future field."

The article unfortunately doesn't specifically say if this method would output frames at 30 or 60fps, but it 60fps seems feasible.

In any case this is all theoretical, because different displays and video processors certainly use different methods. I don't think anyone can make a blanket statement that all fixed pixel displays render 1080i as 30fps or 60fps. It seems that we're left to test our own particular equipment and judge the results for ourselves. It's unfortunate that this is not more standardized.

Traditionally, de-interlacing for playback on a progressive display has always meant recombining the two fields that contain the original frame. The fact that several video processing manufacturers have moved well beyond that idea with proprietary algorithms designed to create 60 frames per second from 60 fields per second is really immaterial at least IMO. They are trying to create something that did not exist as these images were laid to tape, flash, HDD, or whatever in cam. I'm not saying it doesn't work, just that it is not the same thing as capturing 60 full rez frames per second.

I think it is more appropriate to call interlace cameras 60 fields per second cameras because they never capture frames at all, or record frames to tape or whatever, its always fields. They take a field every 1/60 of a second. The field just happens to be half the vertical resolution in discrete horizontal strips( one odd the next field even). That is very different from a picture with complete cover at half resolution. Thus the scene capture rate is 60 fps not 30 fps its just that only half the horizontal strips are being recorded at a time. This of course is very different from a camera capturing 30 frames per second and then processing field information to record. With a CRT phosphor decay our eyes still see the last field when the next is displayed and that is why we perceive a full image at what appears to be 60 fps, not 30 fps. The screen refresh rate is 60hz and the image actually changes every 1/60 sec( just not all of it,but that is true of most images anyway and why it works so well) Our eyes/brain interpolate the missing/decaying horizontal lines and that is what I would hope modern electronics should do on a progressive display. It would be nice to know what manufacturers are creating 60fps though.

Ron Evans

Ron, good explanation. People do get confused with frames and fields and that appears to be why many feel that half the resolution is lost when its not. I do believe that Pioneer at least is creating 60fps in their propietary 'smooth' mode.

I think it is more appropriate to call interlace cameras 60 fields per second cameras because they never capture frames at all, or record frames to tape or whatever, its always fields. They take a field every 1/60 of a second. The field just happens to be half the vertical resolution in discrete horizontal strips( one odd the next field even). That is very different from a picture with complete cover at half resolution. Thus the scene capture rate is 60 fps not 30 fps its just that only half the horizontal strips are being recorded at a time. This of course is very different from a camera capturing 30 frames per second and then processing field information to record. With a CRT phosphor decay our eyes still see the last field when the next is displayed and that is why we perceive a full image at what appears to be 60 fps, not 30 fps. The screen refresh rate is 60hz and the image actually changes every 1/60 sec( just not all of it,but that is true of most images anyway and why it works so well) Our eyes/brain interpolate the missing/decaying horizontal lines and that is what I would hope modern electronics should do on a progressive display. It would be nice to know what manufacturers are creating 60fps though.

Ron Evans

Ron, yes, the traditional summary way of saying what you said is that interlaced video transmits static or slower motion in full resolution at the frame rate, and fast motion in half the vertical resolution at the field rate.

That's the compromise of interlace. You can't have fast motion at full resolution unless you go to full progressive 60 frames per second.

And, yes, it sure would be nice to have a table or list showing which deinterlace methods are used by the various TV's. Someone linked to a page earlier in this thread that lists TVs known or believed to display 24P properly (by shifting the refresh rate, and the Kuros are on that list). Perhaps TVs that have higher quality 24P display also have higher quality deinterlacing in general.

Also of interest may the latest Amberella info.
http://www.ambarella.com/news/press_releases/pr_01072008.htm
Would be interesting to know which cameras use this latest chip too.
Ron Evans

Also of interest may the latest Amberella info.
http://www.ambarella.com/news/press_releases/pr_01072008.htm
Would be interesting to know which cameras use this latest chip too.
Ron Evans

This is definitely a move in the right direction. It may be a long time before broadcasting moves to 1080/60P because of bandwidth limitations, but there is no reason at all that camcorders can't move in that direction. I don't know if the BD spec supports 1080/60P (anyone know?), but if it doesn't, it should be added. Right now, the 60 fps progressive capability of most newer TVs is being partially wasted (unless you've got it hooked to your computer and are playing video games).

The BD disc capacity is so large that there's no reason that movies can't also finally move up to 60 fps, except that the film industry is so attached to the ancient 24 fps look. It sounds stupid, but I'm afraid our great grandkids will still be watching movies at 24 fps 100 years from now.

Knowing how long product design cycles tend to be, I'd be surprised to see this chip even in 2009 model camcorders, but maybe...

Dave, pretty sure the answer to BD spec and 1080p60 is "no" as of today. I guess that means all of the players today will be obsolete as soon as that format is ratified by the BDA because I highly doubt a simple firmware update is going to work. Guess we shall see in the next "X" number of years (before they get their act together).

Ron, GREAT find! A lot of that press release sounds pretty familiar, hmmm? Comparing it to the information presented in this thread, someone might get the idea that I actually wrote it, LOL! It's kinda comical to read between the lines and catch their pitch for their product.

Dave, pretty sure the answer to BD spec and 1080p60 is "no" as of today. I guess that means all of the players today will be obsolete as soon as that format is ratified by the BDA because I highly doubt a simple firmware update is going to work.

Yes, I would think decoding 1080/60P might require additional processing power, so it probably won't be just a firmware update, unless some manufacturers are already anticipating it. On the good side, in a year or two, that second BD player with new capabilities will cost a *lot* less than your first one did ;-)

This concurrent shift to both hi-def and progressive displays is the biggest shift in consumer video technology since TV was introduced, so unfortunately it's taking a few years for things to settle out.

There's an interesting white paper posted at the Amberella site:

http://www.ambarella.com/docs/1080p60.pdf

This talks about using 1080/60P for broadcasting. Initially, one would think that this would take nearly twice the bandwidth of 1080/60i, but it turns out that due to the higher level of vertical correlation within a frame, that it actually takes only around 20% more bandwidth for the same quality.

Another nice find, Dave. Even though there are some typo's in that paper, I think it nicely summarizes a lot of the content of this thread and corroborates what the MIT expert wrote and argued in front of the ATSC adoption panel.

Another nice find, Dave. Even though there are some typo's in that paper, I think it nicely summarizes a lot of the content of this thread and corroborates what the MIT expert wrote and argued in front of the ATSC adoption panel.

Yes, to me one of the more interesting points of the paper is how broadcast infrastructure is now lagging consumer electronics technology where it has always been ahead in the past. The same thing is soon going to happen with color space as in a year or so most all TV's sold will be xvYCC capable. It will be rather ironic in a year or two when a consumer can go from production to display in 1080/60P xvYCC before broadcasting has even adopted one of those new technologies.

Of course the problem is that the broadcasting infrastructure is large and expensive to change, so it will happen more slowly. Nonetheless it's amusing to see that in some respects the envelope is now being pushed by the consumer end.

I finally got a chance to play with the different frame rates on my Canon HF100. With my particular equipment, I get the same result as Ken: video recoded in 30p does not reproduce motion as smoothly as 60i. The difference was most noticeable during panning, where 30p looked a little jumpy while 60i looked smooth. For playback, the HF100 was connected directly to a JVC HD-56FH97 display (60hz LCOS 1080p) via HDMI.

Similar JVCs displays did a good job of deinterlacing in the hometheatermag tests (http://www.hometheatermag.com/hookmeup/1107hook2/), but I have no clue if they are able to properly apply a simple weave to deinterlace 30p content in a 60i stream. Regardless, the end result for me is that 60i looks smoother, so it will be my default recording mode.

Can't say I blame you Bob! ;)

The other day I stopped by a friend's house that happened to have a 32" 1080i Sony CRT TV bought about 4 years ago at the cost of about a fine 50" 1080p LCD set made by most makers today. What surprised me most about it was not the progress of the technology or the cost-effectiveness of viewing today's HD movies. It was the sheer image quality of displaying my HDV footage from my ancient Sony HC-1E (I'm in a PAL land) via the camera's analog component output and my friend's AVCHD footage from his CX-7 also via component. Not only the video looked great by any standard, there were no perceptible artifacts like trailing, blockiness and no hint of noise despite the fact that part of the footage had been shot with gain up to about 12 dB! SD Hollywood movies via $100 DVD player and component scaled up superbly too compared with displaying the same movies on the Sony dealer's new 32" 100Hz 1080p LCD set via HDMI.

I couldn't remember the model but it and a few similar models have long disappeared from the market where I live. I suspect Sony has stopped making them for sometime now. What a pity. The real downside appears to be the size and weight when compared to the LCD or plasma sets. This makes me wish somebody revived all the dead interlaced hi-def CRTs or came up with an affordable 1080 or 720/60p cameras soon.

Wacharapong

Wacharapong, until about 2 years ago I also had a CRT HDTV. It was a Panasonic 34" Tau model. I'm not sure what you're comparing your friend's Sony CRT to in terms of today's technology and brands, but I can tell you that both my Pioneer & Fujitsu plasmas blew away the overall picture quality of the CRT. That Panasonic Tau HDTV was very highly regarded in reviews although I felt the comparable Sony 34" HDTV was a bit better.

I never see noise, trailing or blockiness on the Pioneer Kuro plasma that I use for my primary viewing. The only noise I'll ever see is that which was recorded due to very poor lighting conditions and can even be seen on the camera's LCD. If a display is masking noise that was actually recorded by the camera, then the display is actually not presenting an accurate image.

There is no doubt in my mind that the best plasmas (not LCDs) produce a superior overall picture to consumer CRTs that are still around. Yes, you might find one picture parameter (black level) that still remains superior on the best CRTs, but the overall picture quality is better IMO than consumer CRTs and the latest generation of Pioneer Kuros tremendously narrows the gap even on black level to the point where it's truly not significant. When you factor in picture degrading issues that don't exist on plasmas but do on CRTs such as focus, linearity, convergence, color purity and others, the overall presentation is just better on the best plasmas.

My HD videos as well as broadcast HD surely looks much better on my Kuro than any consumer CRT I've ever seen. Now if you're talking about a $30,000 professional 24" CRT HD monitor, that's another story. But to be honest, I wouldn't even trade that for the sheer cinematic feel of a 60", top-notch plasma.

I had Sony HiScan 1080i TV that my daughter now has in her basement room. It does produce really nice smooth images that I still feel are slightly better than the deinterlacing of the 1080P Panasonic Plasma that I have now. The Panasonic does a better job with SD TV than the Sony and of course is much higher horizontal resolution. The images from HDMI output from the SR11 or SR7 AVCHD into these two TV's give the advantage to the Plasma. The picture is bigger, colour deeper and motion seems smooth. At the moment I view the Panasonic as acceptable but would certainly like to see a manufacturer actually say they are creating a 60p image from the interlace input. That I would like.

Ron Evans

Ron, you should look at the Pioneer Kuro displays. The 9th gen is coming out very shortly. The 8th gen have been recognized as the best flat panels ever in every review written. Many of these reviews have characterized the Kuros as the 'best TV ever, regardless of technology'. When you see a properly calibrated Kuro display, you would never consider going back to CRTs for anything! :)