Journal of New Music Research 2005, Vol. 34, No. 2, pp. 173 – 184 Editorial Metadata in Electronic Music Distribution Systems: Between Universalism and Isolationism Franc¸ ois Pachet, Amaury La Burthe, Jean-Julien Aucouturier and Anthony Beurive´ Sony CSL – Paris Abstract about the artist, the title, and so on. Although you enjoy the new tune, you do not know much about We address the problem of metadata management in the Bjork: you have only been able to classify the artist in context of future Electronic Music Distribution (EMD) your walkman’s local genre taxonomy as ‘‘Electronica / systems, and propose a classification of existing musical Icelandic’’. editorial systems in two categories: the isolationists and As you walk by a cafe´ in Reykjavik, you decide that the universalists. Universalists propose shared informa- you would like to see what information the local tion at the expense of consensuality, while isolationist community has to offer about Bjork (she’s Icelandic, approaches allow individual parameterization at the isn’t she?) You turn on your walkman, which immedi- expense of the lack of reusability. We propose an ately connects to the nearby metadata server at the cafe´ architecture and a system for managing editorial and download locally available information. Unfortu- metadata that lies in the middle of these two extremes: nately, access to the music files is copyrighted and we organize musical editorial information in such a way restricted. However, you have access to the correspond- that users can benefit from shared metadata when they ing metadata. Your walkman automatically browses the wish, while also allowing them to create and manage a local genre taxonomy and is able to trace down Bjork, private version of editorial information. A mechanism although she has been entered with her full Icelandic allows the synchronizing of both views: the shared and name, Gudmundsdottir, and classified in a different the private. genre: Pop/Trip Hop. The local server has a lot of available metadata about Bjork, but its access is restricted to Iceland so you choose to gather metadata 1. Introduction while you are there. Your walkman’s metadata manager is able to fill in the fields corresponding to album, track We propose in this article a short scenario describing listing and recording date, and also downloads the fact how users could benefit from a new metadata manage- that Bjork was a member of another Icelandic band: the ment system. Then, we expose the relationship between Sugarcubes. Your friend back home will certainly be editorial data management (EMD) systems and editorial interested in knowing this! However, you decide to metadata. preserve your carefully built genre taxonomy, and do not update your local genre metadata or Bjork’s full name: it is only useful on the local server because it also holds 1.1 Vision some mp3s of classical music by a female pianist named Picture yourself on a trip to Iceland. Before leaving, Anna Gudmundsdottir. you have obtained a Bjork mp3 from a friend. You You later notice that the local server has a metadata have loaded the file on your mp3 walkman, which field that does not exist in your metadata manager: the already contains about 5,000 of your favorite tunes. mood of the song. You realize how useful this would be Each song on this walkman is associated to metadata: for browsing your own collection. Your walkman Correspondence: Franc¸ ois Pachet, Sony CSL Paris, 6, rue Amyot, 75005 Paris, France. E-mail: [email protected] DOI: 10.1080/09298210500148504 ª 2005 Taylor & Francis 174 Franc¸ ois Pachet et al. matches the many songs that you have in common with Sony CSL’s Music Browser project (Pachet et al., the server, creates a new field in your metadatabase, and 2004), conducted in the context of the Cuidado and uploads the mood information. While you are at it, you SemanticHifi IST projects (http://shf.ircam.fr/; see also download information about the many other songs section 8), consists of designing and implementing a by Bjork that sit on the server. The next thing you do is music browser that gathers all these kinds of metadata. to connect to your favorite online music shop, and buy One exemplar feature of the Music Browser is that it all Bjork’s songs that have the same mood as the one that implements the complete chain linking music titles seen sits on your walkman. As the shop’s server does not as objective items (signals or texts) to users, considered support browsing by mood, you decide to contribute to as complex subjects. This article focuses on editorial their metadatabase by submitting the mood metadata metadata as it is designed and used in the Music about your songs. In return, your point card is credited, Browser. Although some of the architecture and which allows you to download one extra song for free: techniques presented here also may apply to the Why not try this ‘‘Sugarcube’’ thing? management of acoustic and cultural metadata, they will not be discussed here. Notably, connections between our architecture and the MPEG7 standard, 1.2 EMD and editorial metadata which provides a format for representing acoustic The notion of musical metadata is now well established metadata information, will not be discussed (see, e.g., as a key ingredient of systems dedicated to the electronic Herrara et al., 1999). distribution of music audio files. To manage collections Moreover, we place ourselves in the emerging context of audio music titles, either personal or online, an of local and mobile ad hoc networks (MANET) (Basagni application must have access to many kinds of informa- et al., 2004). Ad hoc networks are wireless, self- tion to identify, categorize, index, classify and generally organizing systems formed by cooperating nodes within organize music titles. Because there are so many types of communication range of each other that form temporary information that can be made explicit about music titles, networks. In such environments, different users, with musical metadata comes in many flavors. However, different goals, share the resources of their devices and classifying musical metadata based on its ontological form an open community. A few projects envision music nature is a difficult task because there is virtually no limit browsing in the context of MANETs. SoundPryer to what can be said about a music title. In this context, (Axelsson & O¨ stergen, 2002) describes a system aimed we are interested in metadata that has the following at car travellers that enables the p2p wireless exchange of properties: music files. TunA (Bassoli et al., 2003) is designed for urban pedestrians, and allows the sharing of music as . It is useful – that is, it corresponds to actual features well as information about the user (name, age, etc.) in of the applications targeted. order to foster social interaction. In both systems, the . It is consensual – that is, the information makes sense issue of sharing metadata about the actual content being to a large part of the targeted audience, and these shared is left unaddressed. people would usually agree on them. The distinction between the various forms of musical metadata is usually made based on the way this metadata 2. Existing editorial metadata information is extracted, adopting an engineering viewpoint. Not only systems is this approach easier, but it is probably the only one 2.1 Isolationist versus universalist today that is reasonable. Musical metadata can be divided in the following categories in this scheme: Editorial metadata is no longer a fantasy: they crop up in virtually every musical application. There are, however, . Identification information: this allows for the unique two radically opposed approaches to how this metadata characterization of a music title. is organized. The first, the ‘‘Isolationist’’ approach, . Editorial information: this is related to prescriptive consists of letting individual users handle their metadata knowledge about the music (consensual information, in isolation, with very limited sharing. This is the facts, content description, etc.). approach of most peer-to-peer systems such as Kazaa . Acoustic features: this corresponds to objective, (www.kazaa.com). The second, the ‘‘Universalist’’ ap- acoustic features of the music titles. It is normally proach, consists of creating a central, shared database extracted automatically from the signal. server from which all clients feed. Examples of this . Cultural information: this captures the similarity approach are CDDB (www.cddb.com), FreeDB between music that emerges from socially shared (www.freedb.org), AllMusicGuide (AMG) (www.allmu- sources of textual information such as web search sic.com), MusicBrainz (www.musicbrainz.org) and engines. MoodLogic (www.moodlogic.com). Editorial metadata 175 The isolationist approach consists of letting users benefit of everybody) achieve excellent results. However, manage editorial information themselves. A system such while they are good at expressing consensus, there is no as Kazaa (see Figure 1) proposes different fields based on room for personalization. ID3 tags for describing music titles. The fields are: title, The editorial information system we propose lies in artist, album, category (corresponding to genre) and the middle of these two extremes. We allow both sharing year. Additionally, one can add the language, some of information and local personalization. In the ensuing keywords and a short description of the track. This sections, we will detail the nature of the metadata approach has an obvious drawback in terms of usability: managed and the client-server architecture of the system. users must painstakingly fill in the fields for all the new titles they enter into their collection. There is almost no 2.2 Two kinds of editorial metadata sharing of this metadata, other than through the actual transfer of files. When user A downloads a file from user Editorial information servers such as Musicbrainz, (B), he or she also gets the associated metadata.