User's Manual

Document MV0319P.N

MVN User Manual

12 Saving and Exporting

When a recording has been made, two files are created and saved automatically, one with the file

extension “.mvn” and the other with the file extension “.mvns”. If synchronized video data is recorded, a

movie file “.mpg” is also saved automatically.

MVN (MVN native file) is the most comprehensive format and contains all measured inertial sensor data,

and all kinematic data of each segment. It is a binary proprietary format and can only be used by MVN

Studio or by using the SDK. The MVN files contain all original data and can be used to re-process a

recording using other settings and assumptions or with overruled external contacts. To copy a part of

an MVN file to a new MVN file, select the frames and go to >Edit >Copy to MVN, press ‘Ctrl+B’ or right

click the Timeline.

MVNS is the MVN session file. It contains information about the recorded trials, it is necessary to open

an MVNS file if video data was recorded, or to playback and edit time-synchronized multi-person

recordings.

If video data was recorded, opening the file with extension .mvn will open only the MVN data – the 3D

character in the viewports. Therefore to watch synchronized video data with the MVN data, open the file

with the “.mvns” extension, which will call both the .mpg and the related .mvn files.

If MVN Studio was used for multi-person capture, data of each character is saved in a separate MVN

file, which is synchronized based on the internal clock of the XMs for each suit. This means that for long

files, the number of frames between simultaneously recorded MVN files can differ. However, these MVN

files are grouped in the MVNS file. All recordings in an MVNS file are opened in the same 3D viewport

and will be played back simultaneously. In the MVNS file, all tracks have the same number of frames.

The MVN files will all have the same session name with the suit number as a suffix. For example, the

MVNS file ‘Skating-002.mvns’ consists of two MVN files: ‘Skating-002-suit00.mvn’ and ‘Skating-002-

suit01.mvn’.

MVN (MVN and MVNX) files can be exported to C3D, FBX, BVH or MVNX format. Before exporting a

file to a given format, ensure that the settings are correct. To do this, go to >Options >Preferences

>Exporters. Then go to >File >Export >Export File and select the desired export format. For batch

processing of all active captures, go to >File >Export >Export All Open Files. For batch processing of a

complete folder, go to >File >Export >Batch export. To export only a selected portion of an MVN or

MVNX file go to >File >Export >Export Selection.

There are five main exporters, BVH, C3D, FBX, MVNX, and a Movie Exporter. Each exporter has its

own menu in the preferences section.

12.1 Applying (Smoothing) Filters to Exported Data

The first option to set in the exporters preferences is the filtering. This setting is used only for BVH and

FBX.

12.1.1 Exporter smoothing

The highly sensitive sensor modules capture every twitch and deliver very crisp data. For some

applications, more smoothed motion data is desired. Three options are available:

 No smoothing

 Light smoothing

 Heavy smoothing

The Export Smoothing Filter does not introduce a phase lag. Light smoothing is generally the

recommended option.