Use Case 2: Rare Dancing Knowledge
Use Case 2: Rare Dancing Knowledge
The dance case-study will focus on two specific use cases: contemporary dance and traditional dance. Dance is an immaterial art by essence, as it consists in the motion of the performer’s body. Dance can convey different messages according to the context, and focus on aesthetics or artistic aspects (contemporary dance, ballet dance), the cultural and social aspects (folk dances, traditional dances), a story telling (symbolic dances), spiritual meanings (whirling dervishes), etc. According to the type of dance, the precision of the motion and the way it is executed (referred to as "motion quality") will be of uppermost importance (contemporary dance), or will be secondary as only the functional motion will matter (most traditional dances). Some dances also come with additional accessories like costumes or instruments, which are part of the performance and need to be taken into account as they modify and influence the body motions. The level of detail of the motion that has to be taken into account in order to "capture" and to be able to learn a particular dance will thus greatly vary according to the specific study case. Hence, two scenarios are considered in the dance case study, addressing different levels of detail for motion capture (or mocap) and analysis of 1) Traditional and 2) Contemporary dances.
1. Traditional Dances: This rare dancing knowledge consists of motion patterns that have to be reproduced in rhythm with the music and with the other performers, but where the details of how the motion is performed are less important than the motion itself. Traditional dances can be found all around the world and are strongly linked to local identity and culture. The know-how of the traditional dances survives at the local level through small groups of people who gather to learn, practice and preserve these traditional dances. The aim of this use case is to offer a learning platform open to any traditional dance, preserving and giving visibility to these ICH and enabling anybody to learn them without being physically present in the region where these dances are practiced. For these dances, the costumes or potential accessories are part of the performance and cannot be removed or modified to facilitate the recording. UMONS inertial mocap system along with the Microsoft Kinect 3D motion sensor will enable us to capture the performance with minimal disturbance. The style of traditional dances from different regions will also be studied and compared, along with the similarity of patterns present in different traditional dances. I-Treasures selected severeal traditional dances as sub use cases, specifically: a) Romanian Căluş dance b) Greek Tsamiko dance c) Walloon traditional dances. Depending on the degree of precision of the motion that has to be taken into account and to the constraints posed, different type of sensors will be investigated.
a) Romanian Căluş dance originated as a healing and fertility ritual performed by groups of an odd number of men, bound together by an oath. By the beginning of the 20th century its ritual form survived mainly in southern Romania and among Romanian minorities in northern Bulgaria, although remnants of this custom could be found in much of the rest of Romania, and throughout the Balkans. The Căluş tradition, especially through the art of the dance, caught the attention of the pilgrims, historians, researchers and has always raised the general admiration. The complexity and the mystery of this ritual, along with the virtuosity of the dance accompanying it, attracted the interest of many specialists, who have mentioned, along the time, the beauty and complexity of this custom. At the end of 2005, the Căluş custom was included by the UNESCO in the list of the immaterial masterpieces of humanity.
Figure 1: Romanian Căluş dance
b) Greek Tsamiko dance (Greek: Τσάμικος, Tsamikos) is a popular traditional folk dance of Greece. This dance is probably named from the Tsames in Northern Epirus, but according to other sources it is named from the clothes of the 'klephtes', the mountain fighters in the Greek war of independence. The name of the dance comes from the name used to describe the outfits they wore, which were called tsamika. The main feature of the kleftiko costume is the foustanella, a white pleated kilt. These types of outfits can still be seen today in parades and special events where they are worn by the special segment of the Greek army called Evzones. Tsamikos is a circular dance that is mainly danced by men and with few variations and more smooth steps is also danced by women. It is danced in an open circle and belongs in the category of “dances of the first”, in which apart from the basic steps performed by all the dancers, the first dancer performs squats, turns, jumps, etc. depending on the mood of the moment and its potential, he can also make improvisations according to the lyrics and the melody of the song accompanying the music. When it is danced as mixed circle dance, it is performed in “double banister” (men in the outer circle – women in the inner circle), or in a circle in which men follow women.
Figure 2: Greek Tsamiko dance
c) Walloon traditional dances are essentially peasant dances originated from the 18th, 19th and early 20th centuries and practiced in the Walloon region of Belgium. They were originally mostly danced in popular balls in the villages but almost disappeared at the end of the 19th century and beginning of 20th century. A few people and groups interested in preserving and perpetuating this intangible heritage conducted dance « collections » at their own initiative, by interviewing older people who used to perform the dance and hence where living representatives of this heritage, or found information in notebooks from « ménétriers » (dance leaders) who used to go to local events (weddings, etc.) and in villages to play music and animate the traditional balls.
Figure 3: Walloon traditional dance
2. Contemporary Dance: Contemporary dance is performed by professional dancers, who are in search of aesthetics and emotion expression in the way they dance. For this type of dance, we do not only want to capture the functional motions (turn, flip etc) but also the motion quality. Using optical motion capture will enable us to record with great accuracy the style of the dancers. The details of the motion quality will later be used to classify dancers and enable an intelligent database browsing of the recorded dances based on motion quality criterion. User centered perspectives will be developed building from interviews with contemporary choreographers. The motion quality analysis will also be used in the learning application to assess how an untrained dancer performing the same motions compares to the professional dancer.
Figure 4: Contemporary dance performed by professional dancers
The following type of sensors would be investigated for the capture of motion of the above sub use cases:
i) Optical Motion Capture: optical mocap is the most accurate motion capture technique, but it is also the most expensive and constraining one. The capture area is surrounded by cameras and reflective markers are taped to the performer’s body. These markers are tracked by the cameras and their position in the 3D space can be known on the sub-millimeter precision.
ii) Inertial Motion Capture: inertial sensors attached to the limbs can track the angles between the body segments. This mocap system is less accurate than optical mocap but it is very stable and does not need cameras or specific lighting conditions around the mocap area. Furthermore, as it is not linked to vision, it is the only system that will be able to capture the leg motion under a skirt.
iii) Depth Cameras: Depth cameras such as Microsoft Kinect can track the volume of a performer, and according to his clothes, a skeleton tracking can be extracted. This system is very cheap but the data captured are still noisy and some rotations or body parts cannot be recorded (especially when two dancers interact).
The three main goals of this case study are:
- Develop and study methods for capturing the ICH adapted to our two use cases, contemporary and traditional dances, and use them to enrich the resources of dance ICH available to the public.
- Develop innovative methods for the assessment of the motion quality, the study of the influence of personality and culture on the motion production, and tools for the comparison of dance motions among them (professional vs learner, traditional dances from different countries, personal style of different contemporary dancers, etc.).
- Produce new methods and interfaces to teach and learn dances, giving local dance groups a platform for preserving their knowledge at a broader level and to reach new learners that could not have been involved otherwise.