Optimizing keyframe every frame animation into splines

[cross-roll]

Hello Dr. Sassi

Mixamo animations come with a keyframe for every frame. Is there a way to convert this into a clean animation with keyframes in interpolation mode?

I share an image.
thnx!
Best

[Dr. Sassi]

Hi cross-roll,

It depends on how clean the data was, to begin with, and if there are tiny little errors, like significant changes of keyframe values, while the ones before and after seem to continue otherwise. Those spikes need your judgment. Typically, no actor is able to produce these movements for a 1/60th of a second and then continue with the previous move; at least, I don't, but I have those from time to time in my Mocap sessions as well. Easy to spot and to fix

F-Curve Editor> Function>Key Reducer
https://help.maxon.net/c4d/2024/en-us/Default.htm#html/Key_Reducer.html#PLUGIN_CMD_465001214

How I do it is perhaps pretty simple: I select first all keyframes and set them to linear.
Then, I take first a snapshot of the curves and show those snapshot
F-Curve Editor> Function> Snapshot

With this done, I call up the Key Reducer and pull the first slider as long as I can't see the snapshot. When you can see the snapshot line, the data is altered too much. Explore the Magnet as well.

Here is a 60 second screen capture for you
https://stcineversityprod02.blob.core.windows.net/$web/Cineversity_Forum_Support/2024_Clips_DRS/20240225_Mixamo_Key_Reduction.mp4

Cheers

[cross-roll]

You are a Genius Dr. Sassi
Thnx for the fast reply and kindness for sharing that screen capture.
Its exactly what I was looking for.

[cross-roll]

One more question, I dont understand why we do the Snapshot step since you can reduce the curves without it. Please lmk what the difference is thnx!

[Dr. Sassi]

Hi, cross-roll; thank you very much for the feedback.

Yes, you are spot on:
The Snapshot can be ignored completely.

When you have a longer animation, it is easier to see how far you can reduce, meaning when the new curve is a good fit or too far off.

When I'm short in time, I even delete every n-th keyframe, while the number depends on the mocap captured with 200fps, and perhaps only 24fps is needed. Is that always a good idea? No. But as you might have noticed, more often than not, long character animations with several actors in the scene can limit the performance a little bit.

All the best

[cross-roll]

Amazing. Thnx again Dr. Sassi
Pure gold!

[Dr. Sassi]

I love the sound of that, cross-roll, thank you very much.

Enjoy your project