Reducing mocap FBX file size (from Max)

Polymeddy · Feb 2017

Hey guys

I converted a BVH mocap to a BIP via the Biped's "Motion Capture" tab.
I then got the BIP applied, and exported the animation as an FBX.

Two issues I noticed;

All the keys' tension are set to 50
BIP file is 382 KB (which is nice) but the FBX export of the rig (no mesh) is 9847 KB

The funny thing is every attempt in reducing file size (FBX export settings) only increased the file size (up to 8900 KB at times)

Any help appreciated, please let me know if I can provide useful info.

Eric Chadwick · Feb 2017

You could do some key reduction in Max.
http://help.autodesk.com/view/3DSMAX/2017/ENU/?guid=GUID-1FCA1BEE-D417-45AF-911E-572C0BA43DD4

Polymeddy · Feb 2017

Yeah I already did some key reduction from the BVH to BIP conversion, I'm afraid of losing accuracy from removing anymore

Also I'm really curious what's in the gap between the 382 KB animation and the 9847 KB animation, the biped rig can't be that heavy.. and they're the same amount of keys...

Eric Chadwick · Feb 2017

FBX might be adding a keyframe per frame, whereas the BIP uses interpolation. IIRC there are animation settings in the exporter?

Polymeddy · Feb 2017

Yup, I tried pretty much everything there, key reduction and curve filtering actually increased my file size! Not sure how that works...
My current setting is the lowest FBX size I can get without determining animation accuracy (9847 KB)

Eric Chadwick · Feb 2017

You can embed images in posts. Just drag-n-drop directly into the post editor.

That setting is creating a keyframe every frame.
http://help.autodesk.com/view/3DSMAX/2017/ENU/?guid=GUID-31EA2A4F-A126-498B-96E8-31811522738A

Polymeddy · Feb 2017

Yeah I think that's it.
Adding the step value just adds all bones keys on that frame cycle only, which is a drag because I can't decide which keys are important and which are not, and manually cleaning the keys would be a waste of time in the end.

Is there another animation export format that can have my keys the way I set them in max? for Unity.

Thanks for the embed reminder.

Eric Chadwick · Feb 2017

I'm not an animator, and it's been a long time since I dealt with mocap. But I would look at that help file page I posted. They seem to explain how to reduce keys in the FBX export settings. You could also do some googling, mocap Max Unity, that kind of thing.

Polymeddy · Feb 2017

Sure thing. I read the page and have been googling for a while (still am).
Thank you.

Polymeddy · Feb 2017

Update; Changed FBX file format (in export settings) from "ASCII" to "Binary"; dropped the size from 9847 KB to 3129 KB.
Which is nice.

Reducing mocap FBX file size (from Max)

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