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[Hilton]

Hi all

I've been playing around in MC22 with Frame Interpolation (FI) using SVP in a custom video render mode to experiment with 2:2 pulldown on 24p films (23.976) to double the frame rate to a custom refresh rate of 47.952hz and preserve the natural motion blur of 24p film.

I've got LAV doing decode, MadVR doing Render and ffdshow raw post filter to get SVP working in MC22. (works flawlessly)

This puts an extra interpolated frame between each recorded frame and smooths out motion judder from camera pans and fast motion much like FI does in projectors and TVs that have it.

It actually works quite well and I was wondering what other people have observed, or tried, to reduce the motion judder inherent in 24p films. (not talking about that 24p playback on 60hz judder - I can still see motion judder at native 24p and the projector supports 24p and 48hz)

I've also tried the MadVR smooth motion with 47.952fps but it was causing too much ghosting for my liking.

When using SVP @ 48fps judder is definitely reduced.
I understand that cinemas actually playback films at either 48fps or 96fps with black frame insertion to reduce visible judder (or strobing as it's also known)

I'm using a Benq DLP projector that supports a few custom resolutions as well as native 24p, but I'm just trying to get smoother motion while preserving the natural motion blur of 24p (avoid the soap opera look).

I know reducing the brightness (contrast) of the projector or TV is suppose to reduce this effect of strobing or judder too, but it's still quite noticeable to me with everything playing back at 24p, especially because of the large 120" screen. 

Has anyone else experimented with FI or black frame insertion before?

[Hilton]

And here's the article that got me thinking about it.
http://www.tested.com/art/movies/452387-48-fps-and-beyond-how-high-frame-rates-affect-perception/

[Hilton]

Well.... For those wondering... I've got some good settings that I'm pretty happy with.
After looking at lots of panning scenes and fast action scenes I'm really much happy with the clarity, reduced low speed judder and motion blur.

I've now got about half the motion blur that native 24p film normally creates at it's normal playback speed and it avoids the ghosting that madvr smooth motion creates while still providing some natural motion blur.

The native 24p motion blur with added frame blending of MadVr just didn't look right to me so this is a great compromise for me so far.

Motion still feels natural and not sped up. (like sometimes happens when you insert too many frames with FI and end up with that video look.

I tried 24p to 59hz SVP FI but it was too unnatural, motion blur was virtually non existent and there were sometimes more motion artifacts that became a distraction so 47hz with SVP FI was a good compromise.

The optimum for me was 24p to 47.952hz with SVP.

The end result is that motion resolution looks a little crisper and less blurry which I really like, particularly because I'm using a big screen at 2.5M seating.

I'm using an Nvidia custom 47.952hz refresh rate
SVP FI set to 1.5M
SVP shader complicated
SVP artifact masking disabled
SVP motion vector grid to 16px
SVP search radius large
SVP wide search strongest
SVP width of top coarse level large
MadVR chroma with sharp high quality NGU
MadVR downscaling SSIM
MadVR upscaling NGU Sharp High quality luma
MadVR smooth motion off

I really found 24p motion blur quite distracting before I made these changes and now it just feels natural and easier to watch without feeling like soap opera video.  Really really pleased with the result.

[CountryBumkin]

The article you linked to - seemed to just explain why many viewers don't like 48fps. I didn't get the impression they were advocating the use of it.
I assume you are posting because you like the 48fps look.

[Hilton]

The natural 24p look that people have been talking about for years might have worked on different display technologies, but it just doesn't work real well in the digital world unless directors and camera crews make careful choices about shutter and panning speeds. Many seem to get it wrong in my opinion, even though they know the rules.

I don't like film to look like video but I also don't like the motion blur that's more pronounced in digital displays. In CRTs it looks more natural and smooth, with a digital display I sometimes find it quite jarring and obvious and not in a good way. 

Running at 48fps halves the motion blur so moving objects and pans that move faster than the shutter rate that was used to film it, don't look so stop motion or blurry. Its a fine line I have to say though between being too super pristine video like and being a blurry mess.

So 48fps was a good compromise for me because it preserves some of the natural films motion blur. 24p motion blur in many movies in my opinion is way too obvious on a fast switching display like a DLP projector that I use.  On LCD panels or LCD projectors it creates it's own different set of problems relating to ghosting which is another issue I don't like.
Ghosting images also partly obscure the natural motion blur but make the image look too blurry for me and defeat the purpose of having a HD screen.

In anycase, I was sceptical that I would like 48hz with the FI that SVP uses but I've found it really does improve the viewing experience dramatically. I'm not so taken out of the moment because my eye doesn't get stuck on a blurry edge of an object, but rather just follows it more naturally.  Unless you've played around to see the difference you might not know what I'm talking about, but lets just say I'm a converted sceptic.  I think 48hz more naturally matches what was intended when films were first displayed in cinemas at 48fps and 72fps with the shutter wheel blacking out frames to improve motion and reduce flickering.

Edit: just a note that DLP projectors are known for their really high sharpness and the best motion resolution at faster frame rates - so they really do show up bad panning and fast action blur quite dramatically at 24p - conversely LCD and other 3 panel colour devices have lower sharpness and a natural blur (slow response time). DLP switches pixels 1000x faster than the best LCD display technologies.

[jmone]

On a similar vein, I've had a play with Billy Lynn's Long Halftime Walk on UHD BD that is presented in 60fps and HDR.  This was all on my first 10min on my new HT setup as I was excited to see what 4K/HDR/60fps would look like!  First impression was it was horrific with:
- cheap soap opera look (I always thought this was just a myth till I saw it with this disk),
- depth was weird,
- movement strange, and
- you could see all sorts of details of the set that took you out of the movie (the uncanny valley). 

However.... once I'd playing with the settings PJ, AVR, Xbox One S it completely changed this.  Now it looks great just more "real" without the uncanny valley or soap opera effect.  I think I'll go check it out again to be sure

[Hilton]

When do I get a movie night invite? I'm really keen to check it out!! I'm considering a Benq W11500 or W12000 or a Optoma HD65 but would love to see what 4K large screen looks like compared to 1080P.

[jmone]

Good Idea!  we should get a rotating Sydney Movie Night going for JR'ers.  Only downside is getting unencrypted UHD content for MC to play  

[Hilton]

Might not be too long to wait - the first couple of UHD rips have been discussed around the place.  Nothing official from anyone but they look legit with the entire structure intact from disc.  Someones found an exploit in either Intel SGX, cyberlink or something else. I don't think aacs2.0 is done yet.

[jmone]

With a bit of luck a decrypter will become available and then some fine tuning of the DirectShow components will be needed so we can play them in MC. 

[blgentry]

This is a really interesting topic.  I've seen, first hand, the very weird looks that different digital monitors produce.  I'm not sure if I've experienced the Soap Opera Effect or not.  I've definitely seen the "too smooth" thing... having a hard time remembering exactly what I saw and why I didn't like it.  I've also experienced REALLY weird things with some sources where still frames look like HD, and moving images looked like standard def, or perhaps worse with macro-blocking and other nasty visual artifacts.  I know these are distinct and different things.  Just describing some of the weirdness of digital display technology.

I've been watching film based movies for nearly 40 years now, so my brain is definitely used to that look.  However, I started noticing several years ago, that film didn't really look all that good.  At the time, I thought I was starting to realize that film's resolution and refresh rate were not all that great.  But now, reading what you guys have been saying here, I'm not sure sure.

An example I go back to in my mind over and over again is The Day After Tomorrow.  I saw TDAT in a very new AMC theater in Miami when it came out, in 2004.  I wouldn't be at all surprised if that theater had digital projection at that time.

There are some long pans in the "ice shelf break" scene that looked awful in the theater.  They seemed to flash and stop-start stop-start.  I think the bright white background had a lot to do with this.  But now I'm not sure sure that it's a 24 fps problem, but perhaps a conversion issue to whatever frame rate was being used in that theater.  I found several clips of this on youtube that look bad.  This one looks the best of the two I demoed:

https://www.youtube.com/watch?v=jBssLrx67Xc

Look at the last 20 seconds or so and around the 50 second mark.  The end has the more dramatic pan that really juddered like crazy in person.

Man video is complex!  You would think we'd have all this figured out by now wouldn't you? 

Brian.

[Hilton]

Just another quick update


I managed to overclock the HDMI input on the projector with a custom NVidia resolution to get an exact 71.928hz @ 1920 x 1065 res to run triple frame interpolation with SVP.
That's a loss of 15 lines of resolution from the top of the screen on full 16:9 material and no difference to 2.39:1 widescreen film because it's only 1920 x 802 res anyway.
(BTW the loss of res is not noticeable because it's all cropped from the top of the screen so doesn't distort the image and it's a very small amount)

Motion blur is further improved from the 48fps settings.  Still not sure I like the end result more than native 24p with natural motion blur but I'll stay with it for a while to see if I get used to it.