stabilasing facial mocap?

[zveris]

Hi,

anyone has a good idea how tostabilace head motion in a facial mocap data, I mean how to filter out head translation and rotation, and just keep facial motion.

Thx

zveris

[Mcronin]

You can find the channels that control the rotation of the head and remove them, easily enough. Another thing you could do is point a camera straight on at the face, and put a fixed bone or null in the face that's a child of whatever skeletal network you have in the face (the tip of the nose is a good spot) and make the camera a child of this bone or null. Then, you can keep the channels that control the movement of the head if you like, but will always have a view that looks straight on at the face.

[zveris]

well, it aint no that simple. Can't use camera walk arround, I have to reanimate character with facial mocap. And mocap itself is just a marker points with translate channels, so no strraight forward rotate or translate removal. Somehow I have to detect global motion and substract it from mocap data. Question how?

[edward]

This is actually where the Handle Chop comes in handy. Unfortunately, I never did find the chance to create that example I promised. Sorry, people.

Here's what you do. Load the mocap data into chops and create a corresponding null object for each marker so that they reproduce the marker animation in your scene. Now create the bone hierarchy for which you which to track the markers with. Using the attached script, create Handle objects for each of your markers, attaching them to bones. To use this script, first do something like this:

alias F1 'source path_to_file/add_handles.cmd'

(where path_to_file is the path to where you saved the script)

Now so can select some nulls objects along with the bone you want to attach in the viewport. Hit the F1 key to run the script on your selected objects. It will create a handle object for you linking the bone with that marker null. In most cases, you will want to simply select one bone and one null marker object but sometimes you might want to group two or more of them together to act as one "handle".

Once you have your markers set up with the bones, go into CHOPs and put down a Handle CHOP. In the Source parameter, choose all the bones for your head. Now turn on the export (orange) flag on the Handle CHOP. Now your bone should track the marker data. Play around with the Handle CHOP's parameters to control how it tracks.

[edward]

Here's the script:

add_handles.cmd

[zveris]

thanks, got to try it. Although meanwhile I deviced other metod using object chan ops. t worked just fine.

zveris