User's Manual

Document MV0319P.N

MVN User Manual

In the default BVH hierarchy, the character is in a T-pose. Use the 3ds Max exporter to write a neutral

pose (arms parallel to body). Use the Poser exporter to reduce the number of chest segments from 4 to

The motion section begins with the keyword ‘MOTION’. This line is followed by the number of motion

frames by the keyword ‘Frames’ and ‘Frame Time’, indicating the sampling rate of the data. The rest of

the file contains the actual motion data; the X, Y and Z position of the root segment and Euler angles of

each segment with respect to its parent segment. Each line is one sample of motion data. The numbers

appear in the order of the channel specifications as the skeleton hierarchy was parsed.

It should be noted that the BVH format is restrictive and it does not reflect the full information as captured

with MVN. The numerical resolution of BVH files is limited compared to the MVN and MVNX files. The

Euler angle conversion may cause round-off issues in certain poses (singularities). Since all segments

are rigidly connected (which is not the case in the MVN Fusion Engine) some foot slide may occur since

all errors such as mainly soft tissue artefacts are ‘projected’ on the feet. However, the LXsolver removes

this on export, see 12.1.2. Further optimization can be done by using inversed kinematics (IK) solvers

which are usually available in animation applications and which are also necessary for retargeting the

motion data to different characters.

The BVH format does not support multi-person recordings. For each person a separate BVH file will be

made.

Set the BVH preferences. An explanation of each option is provided below.