Long-term Preservation of Acousmatic Works: Toward a Generic Model of Description
N. Esposito1 and Y. Geslin2
Abstract—Acousmatic works are defined at INA-GRM as pure recorded music that is without live instrument or electronic interaction. Usually, the archive of those pieces consist on a single final tape and its security copies, nowadays a single digital file. In the framework of the CASPAR project3, it appears to us that it is very important to archive more elements (variants, source elements, notes, etc.) to perform intelligibility preservation over the long-term. Our proposal is to archive these elements regarding the life cycle of an acousmatic work. We provide a model to represent such a life cycle. This model is based on a method which starts with files to finally get a description of the life cycle. This method was applied to a well-documented work: the Hans Tutschku's recent piece Distance Liquide. A model was built on the description of this work. It was validated with other acousmatic works. Then, it can be considered as a generic acousmatic model. It currently uses the CIDOC-CRM ontology. Index Terms—Art, Design methodology, Knowledge representation, Modeling, Long-term preservation, Acousmatic music.
I. INTRODUCTION Acousmatic works are defined at INA/GRM as pure recorded (tape) music that is without live instrument or electronic interaction. Usually, the archive of those pieces consist on a single final tape and its security copies, nowadays a single digital file. In the framework of the CASPAR project [2], we focus on long-term preservation. And then, we have to preserve the intelligibility of a work over the long-term. Thus, it appears to us that it is very important to archive more elements of an acousmatic piece, i.e. the final mixing session and their variant, and furthermore the source elements. This is proposed mainly to ensure the possibility of enhancing the sound quality in further times. It means that we need a model to describe this kind of work, to architecture this information into an archive. This paper proposes such a model. We will present our methodology (starting from the files we collect) and the generic model we obtained which is based on a life cycle representation.
1 Nicolas Esposito, CNRS UMR Heudiasyc, Centre de recherches, 60200 Compiègne, France 2 Yann Geslin, INA/GRM, Maison de Radio-France, 75220 Paris cedex 16, France 3 CASPAR project: http://www.casparpreserves.eu/ STFC (CCLRC) – David L. Giaretta, project leader, ACS, Asemantics, Ciant, Engineering, ESA, Forth, IBM Haifa, Ina, Ircam, Metaware, Unesco, Univ. Glasgow, Univ. Leeds, Univ. Urbino.
II. METHODOLOGY The model to represent acousmatic works was built by applying a method on several acousmatic works. This method is described below. The first work was Hans Tutschku's recent piece Distance Liquide, because we had numerous files about it. It provided us a first model that we confirmed and validated with other acousmatic works. We use a file-based method to describe an acousmatic archive: the files give us a first group of elements that we can link. These files have to be collected, selected, and classified. Then, they can be used as a first version of each level of information (e.g. main creation flow, additional information about the main creation flow, documents and rights). This first version can be completed later and we can also look for new files. The files about our examples were collected by Yann Geslin, researcher but also specialist and composer of electroacoustic music, with help of the composers. This was made either after the creation process, either during the process in the case of Hans Tutschku's work. Collecting these files during the creation process allows to avoid missing documents and to create documents especially for an archive purpose (for example: videos of a rehearsal). These files can be collected by an archivist, by a musical assistant, or by the composer himself. It depends on the organization of the institution. A. Main Steps Collecting files—All files directly related to the work (e.g. work items, files about the work). Files were collected from the GRM hard drives and from the composers themselves, and some files were produced especially for the archive (e.g. photos and videos). See figure 1. Selecting files—Keeping only pertinent files (e.g. removing duplicates). Some files and folders were not selected. For example, a low resolution photo because a high resolution of this photo was in another folder. Another example, a folder was not selected because it was outdated (another folder contained the same files, but newer). Defining levels of information and classifying files—Choosing, for each file, a level of information. We defined four levels of information: main creation flow, additional information about the creation flow, documents, and rights. And then, we classified the selected files by using these four levels. These levels of information will be described later in this paper. Modeling the main creation flow—The answer to the questions “who did what?” from the author to the performance. Adding more information—Alternative versions, equipment, etc.