Tools
As described in the methodology, several tools and techniques were employed.
Gestures were analysed using both holistic and accurate methods. Video data provided more generalized information about a performer's movements, while motion tracking using the Optotrak or the Vicon systems coupled with MATLAB analysis routines provided accurate information about performer movements.
Video Analysis
Video analysis was used for a global, holistic examination of the performances. We used several tools for this purpose, including Final Cut, EyesWeb, Anvil and the Musical Gestures Tools.
- See a comparison of a
standard and a expressive performances of one player (Marie-Julie
Chagnon). Note that frames have been cut in order to ensure the
alignment of each musical phrase. One can listen to the melodic line
and hear the degree of musical-synchonization across different
performances.
- example patch
- an example video showing areas of movement in red (warning: not compressed, so very large file)
Anvil was used to annotate performer movements using two different sets of parameters: a) descriptive parameters (clarinet movements, postural adjustments, etc.) and b) Laban-Bartenieff movement principles (see section on observation for more information on LBM principles).
Anvil (created by Michael Kipp) uses a movie file, allowing the user to have a holistic picture of the event to be annotated. The user declares all the gesture types he/she wishes to annotate in an .xml file (for example see oswald_project.xml ). Once this is done he/she can then indicate the time a particular gesture occurs while viewing the movie file.
This screenshot shows the types of gestures one wishes to capture on the left. It is immediately obvious that the circular movement under 'clarinet gestures' takes a longer time than an 'up' or 'down' movement, for example. Also one can spot trends, for example, the up-down movement of the clarinet is very correlated with the up-down movement of the head and to a lesser extent the movement of the back (under 'upper body').
In the screenshot it was decided to annotate variables--without any prior reading of gesture classifications such as Laban-Bartenieff techniques--which were very obvious in the video. The variables were grouped in 'clarinet gestures', 'head movement', 'upper body' and 'lower body'. Also in hindsight there isn't really any difference between 'body sweep' and 'body weight emphasis'.
The anvil files used are available on demand.
The Musical Gestures Tools is a collection of software tools for helping in qualitative and quantitative analysis of movement and sound. The toolbox is built with Max/MSP/Jitter from Cycling '74, and is available for Mac OS X and Windows.
MATLAB and Optotrak
