Video Quality for Intro/Outro Videos

[Kerry000]

TL;DR: 60fps is where it's at. Avoid 29.97fps if your video includes pans at a constant rate. The engine handles 60fps just fine. 

Hello everyone,

I decided to try a change of framerate on the intro for the Hare in the Snare FM in order to minimize the judder that's been annoying me ever since I saw it in someone's playthrough video on YT last week. That's the jittering effect you see when a high-contrast scene pans across the screen at a constant rate, without heavy motion blur. This judder is also prevalent in the excellent intro video in Volta 3 by @kingsal. It's caused by a combination of your monitor's refresh rate misaligning with the precise framerate of a video, and the human brain's habit of creating an image where it expects the next frame to be (the human eye has an equivalent "refresh rate" of around 120 to 200Hz, so they say). 

Anyway, long story short, I've been experimenting with 60fps instead, and it works really well. Just be sure to keep the bitrate under 8Mb/s for compatibility with any users running older hardware.

The wiki still recommends the standard framerate of 29.97, but I think that should be updated. 29.97 is not good for slow pans (the "camera" moving across the screen) at a steady rate. Also, for what it's worth, don't bother with 48kHz audio. 44.1kHz at 128kb/s is more than enough for a briefing video.

@kingsal, feel free to chime in, but I 'd suggest that a change of framerate to 60fps to your briefing video would eliminate the judder completely. 

The nature of TDM is such that our videos are pretty much always going to be high-contrast in a flat-shaded, comic style. And that's where judder always ruins the day. A higher framerate fixes it. Until people start making 3D or realistic AI videos for their FMs, that is. Although changing to a realistic style via AI would be a real shame, IMO.


 

[OrbWeaver]

EDIT: Never mind, I've already wasted enough of my life arguing on the internet.

Edited August 13, 2025 by OrbWeaver
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[Kerry000]

On 8/11/2025 at 9:20 PM, OrbWeaver said:

It's good advice, but I don't think the explanation is quite correct. It's not about alignment of framerates with the monitor refresh rate or the human visual system's motion prediction — it's just that 29.97 or 30 FPS is a low framerate, and high contrast pans are always going to look juddery at that FPS. You'd see exactly the same thing when moving the camera around in game if the FPS was only 30, which is why gamers don't generally consider 30 FPS acceptable.

I'm guessing you haven't heard of the human critical flicker fusion threshold when tracking detail? No matter. First, let me explain how a refresh mismatch on a monitor causes judder:

29.97 is the standard the world over and you don't get judder with accelerating pans, or if you follow the 7-second-rule, and it absolutely is related to a refresh rate mismatch. 30 fps is still 30 images per second, or an image every 33 milliseconds. That is not slow at all, and it's still the framerate for big budget movies. There's a reason that judder can be bad on one monitor and yet look really smooth on another one. For example, the Hare in the Snare intro had no judder on my old 60Hz monitor, but on my 180Hz screen the judder is very noticeable. 

Here's an exact scenario where a monitor's refresh mismatch alone causes judder:

Source: A film shot at 60fps
Display: A monitor fixed at 90Hz 
Result: The video player uses a 2:1 pulldown to fit the 60 frames into 90 refresh cycles --> This leads to uneven timing, otherwise known as a refresh mismatch --> And this can still happen with a film shot at a high 90fps and displayed on a 60Hz monitor, for example --> Because the video player has to squeeze or stretch the footage to match the refresh rate, which means some frames get played twice if the footage was a lower fps, and some frames get dropped completely if the footage was a higher fps.

As for how the brain can cause judder:

Source: A film shot at 60fps
Display: A monitor with a native 60Hz refresh rate
Condition: The pan speed is near or above the critical flicker fusion threshold for tracking detail

Have you ever seen footage of helicopter blades that appear to spin slowly or spin backwards? Or a wheel on a car or an old wagon? That happens in real life too. If you put a spotlight on a fan and spin it at different speeds, you'll get to a point where you see the blades look like they're spinning backwards, or spinning slowly. That's the human brain filling in the gaps wrong. And it does the same thing when watching a pan across a scene. This is all documented science, you can look it up.

That said, the whole point of my post was not to explain WHY judder happens, but to say that we can use 60fps in our videos, and that I have tested it inside TDM and it works.

Edited August 15, 2025 by Kerry000

[datiswous]

@Kerry000are you still interested in making a followup to The Hare in the Snare? I tthink the mission's story is kind of unfinnished with part 1 only. It would be nice, but no pressure.

[Kerry000]

1 hour ago, datiswous said:

@Kerry000are you still interested in making a followup to The Hare in the Snare? I tthink the mission's story is kind of unfinnished with part 1 only. It would be nice, but no pressure.

Hi @datiswous. Yes,, I would love to continue with the next part. The HitS story is quite a tale that would take place over several missions, and it is entirely my own fault that the next part is not complete. @Frost_Salamanderwas the lead on HitS and he's still very active here, as you know, but my life got upended shortly after we released Hare in the Snare and I was unable to continue assisting him. He, on the other hand, kindly set it aside as a courtesy to me, as a project we'd only work on together.
I am unfortunately not yet in a position to dedicate the time the next mission needs right now, but I have indicated that I'd likely be able to get involved again some time next year. Thank you for asking about it. It is still close to my heart. As are the recurring characters in the plot.

[datiswous]

On 8/12/2025 at 3:59 PM, Kerry000 said:

but my life got upended shortly after we released Hare in the Snare and I was unable to continue assisting him

So therefore it's not your fault. It would be nice if the story moves on in a second mission, but I'm also thankful already for part one.