[FFmpeg-user] telecine pattern 5555 - Judder-free, 60 FPS telecine (?)

[Mark Filipak]

On 04/05/2020 06:21 AM, Moritz Barsnick wrote:
> On Sun, Apr 05, 2020 at 04:23:35 -0400, Mark Filipak wrote:
>> Those are the facts. I don't think 5-5-5-5 telecine to 60fps has ever been done before. Some people
>> are opposed to it as though it is religious heresy. That's not going to stop me.
> 
> Combing may be more visible than judder. But this is totally up to you.

The 5-5-5-5 pull-down telecines I've made have less combing than an ordinary 2-3-2-3 pull-down 
telecine. Regarding decombing, I'm working on that.

>> I hope that someone will respond to it. But even without decombing, I consider the 60fps video to be
>> superior to any 2-3-2-3 pull-down telecine because I hate judder.
> 
> Now you've combed your content, why do you want to decomb?

Um, to eliminate combing? Only frames 3 & 8 (out of every 10 frames, 1-based) are combed.

> And here you write:
>> Once transcoded to 60fps, why would I ever reverse it?
> 
> But didn't you just request to decomb? You lost me there.

Look, if you transcode 24fps to, say, 30fps, your telecine has 2 combed frames. Decombing doesn't 
convert it back to 24fps. It just decombs the current, 30fps frames.

> I'm under the impression that I get judder-free playback from anything
> from 24000/1001 up to 60 fps material on my TV fed from a PVR as media
> player, but I can't tell you which component does conversion to achieve
> a nice display.

A couple of minutes ago I IRCed with the MPV developers. They said that when I switch the TV to 
24/1.001Hz via my NVIDIA control panel, Windows and the NVIDIA GPU get out of the way and that I can 
test it with MPV, Shift-I to be certain. I, of course, use Shift-I (Information) all the time, but I 
also can query the TV via HDMI capabilities with the MonInfo utility. Once I've pushed Windows and 
NVIDIA out of the way, I can play p24 with MPV and the TV will, for sure, get only p24. Now, I'm 
quite confident that the TV will accept it -- it accepts 23Hz to 76Hz -- but I quite confident that 
the TV will telecine to p60 before driving the flat panel. I will know that based on judder. If the 
display doesn't judder, then the TV actually syncs to 24fps. If the display does judder, then the TV 
is telecining. I quite confident it will judder.

Unfortunately, I can't switch the TV on without crashing Windows (because Windows washes its hands 
of any responsibility for HDMI). So, I must quit this browser, shut down Windows, turn on the TV, 
and restart Windows. Stand by. I will return.

> I do realize that some people like to upconvert their
> material to 60 or 120 fps. The Universal Media Server (UMS) and its
> derivates does have capability to do this, you might want to check out
> how they achive it. (I think they call it InterFrame and True Motion.)

True Motion is telecine plus decombing of those frames that are combed via pixel interpolation and 
motion vector compensation. That's what I'm trying to accomplish with ffmpeg. The reason I need to 
5-5-5-5 the video to 60fps is to take the first step because my TV doesn't have True Motion. Whether 
my TV will accept 24fps will be answered in a few minutes, but first I need to shut down Windows so 
I can switch on the TV connected to the display port.

Gee, I hope everyone knows now what I've been trying to do. I've been dodging bomb throwers all the 
way. It's getting tedious.

> Moritz