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With the development of gesture controllers, haptic systems, motion capture systems, etc, on the one hand, and with the need of allowing virtual reality systems to inter-communicate through control data, the question of gesture and motion takes more and more importance.
Motion and gesture file formats are widely used today in many applications that deal with motion and gesture signal. It is the case in domains like motion capture, character animation, gesture analysis, biomechanics, musical gesture interfaces, virtual surgery. Those formats are low-level formats, i.e. formats close to the signal produced by the capture system.

Contents

Existing format that encode gesture and motion

BVA and BVH file formats

MNM file format

ASK/SDL file format

AOA file format

ASF/AMC file formats

BRD file format

HTR and GTR file formats

TRC file format

CSM file format

V/VSK file format

C3D file format

GMS file format

See also

External links

Existing format that encode gesture and motion

BVA and BVH file formats

BVH means Biovision Hierarchical Data. This format is one of the most currently used today. At the basis, Biovision, a motion capture company, has developed it. The BVA format, also developed by Biovision is the BVH primal form. This format is mainly used for the animation of humanoid structures and gives a standardised definition of them. The format is largely and successfully spread in animation community certainly because of its simple specifications.

MNM file format

This file format allows renaming the segments of a BVH file to match the convention used in Autodesk 3D Studio Max. The name defined by the user is associated to the predefined label for the biped segment.
''eg. Humerous = L UpperArm''
This file format also allows renaming the markers of a CSM file to match the convention used in Autodesk 3D Studio Max. A name defined by the user is associated to the predefined label expected by Character Sudio.
''eg. LeftShoulder = LSHO''

ASK/SDL file format

The format is a variant of the BVH file format developed by Biovision. The ASK file (Alias Skeleton) only contain information concerning the skeleton and, as a result, does not contain any information about the channels or the movement. The offset coordinates are absolute unlike the BVH in which they are relative.
The SDL file associated to the ASK file contain the data of the movement but it can contain many other information concerning the scene than the very samples of the movement.

AOA file format

Adaptative Optics is a company dedicated to the creation of hardware support for the motion capture. This ASCII file format simply describes the captors and their position at each sampling period.

ASF/AMC file formats

This format was developed by Acclaim, a video game company. Once entered in the public domain it has been used by Oxford Metrics (Vicon Motion Capture Systems).
The Acclaim format is composed of two different files, one for the skeleton and the other one for the movement. The separation between these two types has been done because the same skeleton is often used for numerous distinct movements. The file containing the skeleton description in the ASF file (Acclaim Skeleton File) and the file containing the movement data is the AMC file (Acclaim Motion Capture data).

BRD file format

The format is uniquely used by the motion capture system Ascension Technology “Flock of Birds” developed by LambSoft. It allowed stocking the data coming from a magnetic motion capture system.

HTR and GTR file formats

The HTR format (Hierarchical Translation Rotation) has been developed as a native format for the skeleton of the Motion Analysis software. It has been created as an alternative to the BVH format to make up for its main drawbacks. A HTR variant exist which is called the GTR format (Global Translation Rotation) and is the same format less the structural information.

TRC file format

The TRC file format is another file format from Motion Analysis. It contains not only the raw data from the full body motion capture system they developed but also the output data coming from their face tracker.

CSM file format

The CSM format is an optical tracking format that is used by Character Studio (an animation and skinning plug-in for 3ds Max) for importing marker data.

V/VSK file format

The V file format is a binary motion data format developed by Vicon Motion Systems. This file is normally used in conjunction with a VSK file also developed by Vicon Motion System. The VSK file contains the skeleton Hierarchy. The V file can contain the following data:

- Marker data

- Global segment translation and rotation data

- Local rotation data (with root translation data)

C3D file format

The C3D file was developed by The National Institute of Health. Many of the motion capture companies are often linked to the biomechanics research. The systems are then used to assess the performances of an athlete or the needs of a physically handicapped person. The needs of researchers, often supplied by more than one society, lead to the definition of a common format, the C3D format. This format has been built following this philosophy, so it has tried to carry the most complete amount of information useful for the biomechanics research. The features below was considered as necessities:

- The possibility to stock analogical data (i.e. directly coming from the measure instrument) and three-dimensional data (obtained by the information processing).

- The possibility to stock information on the material, which have been used (position marker, force captors), on the recording process (sampling rate, date, type of examination…), on the subject itself (name, age, physical parameters…).

- The possibility to add new data to the ones already recorded.

- The file was a binary file unlike most of motion capture file format, which often are ASCII files.

GMS file format

The GMS format is a low-level, binary, minimal, but generic, format for storing Gesture and Motion Signals in a flexible, organized, optimized way. The GMS format takes into account the minimal features a format carrying movement/gesture information needs: flexible dimensionality for the signals, versatile structuration, flexible types of the encoded variables, and spatial and temporal properties of gesture and motion signals.
GMS received the support of the the FP6 Network of Excellence IST-2002-002114 – "Enactive Interfaces".

See also

★ file format

★ signal

★ motion capture

External links

★ AOA, BRD,BVH, BVA, HTR

★ ASF

★ C3D

★ CSM

★ GMS