Tim Pohle

A music search engine built upon audio-based and web-based similarity measures

An approach is presented to automatically build a search engine for large-scale music collections that can be queried through natural language. While existing approaches depend on explicit manual annotations and meta-data assigned to the individual audio pieces, we automatically derive descriptions by making use of methods from Web Retrieval and Music Information Retrieval. Based on the ID3 tags of a collection of mp3 files, we retrieve relevant Web pages via Google queries and use the contents of these pages to characterize the music pieces and represent them by term vectors. By incorporating complementary information about acous tic similarity we are able to both reduce the dimensionality of the vector space and improve the performance of retrieval, i.e. the quality of the results. Furthermore, the usage of audio similarity allows us to also characterize audio pieces when there is no associated information found on the Web.

An innovative three-dimensional user interface for exploring music collections enriched

We present a novel, innovative user interface to music repositories. Given an arbitrary collection of digital music files, our system creates a virtual landscape which allows the user to freely navigate in this collection. This is accomplished by automatically extracting features from the audio signal and training a Self-Organizing Map (SOM) on them to form clusters of similar sounding pieces of music. Subsequently, a Smoothed Data Histogram (SDH) is calculated on the SOM and interpreted as a three-dimensional height profile. This height profile is visualized as a three-dimensional island landscape containing the pieces of music. While moving through the terrain, the closest sounds with respect to the listeners current position can be heard. This is realized by anisotropic auralization using a 5.1 surround sound model. Additionally, we incorporate knowledge extracted automatically from the web to enrich the landscape with semantic information. More precisely, we display words and related images that describe the heard music on the landscape to support the exploration.

Exploring Music Collections in Virtual Landscapes

A user interface to music repositories called nepTune creates a virtual landscape for an arbitrary collection of digital music files, letting users freely navigate the collection. Automatically extracting features from the audio signal and clustering the music pieces accomplish this. The clustering helps generate a 3D island landscape. The rapidly growing research field of music information retrieval is developing the technological foundations for a new generation of more intelligent music devices and services. Researchers are creating algorithms for audio and music analysis, studying methods for retrieving music-related information from the Internet, and investigating scenarios for using music-related information for novel types of computer-based music services. The range of applications for such technologies is broad - from automatic music recommendation services through personalized, adaptive radio stations, to novel types of intelligent, reactive musical devices and environments.

“Reinventing the Wheel”: A Novel Approach to Music Player Interfaces

We present a novel interface to (portable) music players that benefit from intelligently structured collections of audio files. For structuring, we calculate similarities between every pair of songs and model a travelling salesman problem (TSP) that is solved to obtain a playlist (i.e., the track ordering during playback) where the average distance between consecutive pieces of music is minimal according to the similarity measure. The similarities are determined using both audio signal analysis of the music tracks and Web-based artist profile comparison. Indeed, we show how to enhance the quality of the well-established methods based on audio signal processing with features derived from Web pages of music artists. Using TSP allows for creating circular playlists that can be easily browsed with a wheel as input device. We investigate the usefulness of four different TSP algorithms for this purpose. For evaluating the quality of the generated playlists, we apply a number of quality measures to two real-world music collections. It turns out that the proposed combination of audio and text-based similarity yields better results than the initial approach based on audio data only. We implemented an audio player as Java applet to demonstrate the benefits of our approach. Furthermore, we present the results of a small user study conducted to evaluate the quality of the generated playlists

The CoMIRVA toolkit for visualizing music-related data

We present CoMIRVA, which is an abbreviation for Collection of Music Information Retrieval and Visualization Applications. CoMIRVA is a Java framework and toolkit for information retrieval and visualization. It is licensed under the GNU GPL and can be downloaded from http://www.cp.jku.at/comirva/. At the moment, the main functionalities include music information retrieval, web retrieval, and visualization of the extracted information. In this paper, we focus on the visualization aspects of CoMIRVA. Since many of the information retrieval functions are intended to be applied to problems of the field of music information retrieval (MIR), we demonstrate the functions using data like similarity matrices of music artists gained by analyzing artist-related web pages. CoMIRVA is continuously being extended. Currently, it supports the following visualization techniques: Self-Organizing Map, Smoothed Data Histogram, Circled Bars, Circled Fans, Probabilistic Network, Continuous Similarity Ring, Sunburst, and Music Description Map. Since space is limited, we can only present a selected number of these in this paper. As one key feature of CoMIRVA is its easy extensibility, we further elaborate on how CoMIRVA was used for creating a novel user interface to digital music repositories.

Exploring the music similarity space on the web

This article comprehensively addresses the problem of similarity measurement between music artists via text-based features extracted from Web pages. To this end, we present a thorough evaluation of different term-weighting strategies, normalization methods, aggregation functions, and similarity measurement techniques. In large-scale genre classification experiments carried out on real-world artist collections, we analyze several thousand combinations of settings/parameters that influence the similarity calculation process, and investigate in which way they impact the quality of the similarity estimates. Accurate similarity measures for music are vital for many applications, such as automated playlist generation, music recommender systems, music information systems, or intelligent user interfaces to access music collections by means beyond text-based browsing. Therefore, by exhaustively analyzing the potential of text-based features derived from artist-related Web pages, this article constitutes an important contribution to context-based music information research.

A document-centered approach to a natural language music search engine

We propose a new approach to a music search engine that can be accessed via natural language queries. As with existing approaches, we try to gather as much contextual information as possible for individual pieces in a (possibly large) music collection by means of Web retrieval. While existing approaches use this textual information to construct representations of music pieces in a vector space model, in this paper, we propose a document-centered technique to retrieve music pieces relevant to arbitrary natural language queries. This technique improves the quality of the resulting document rankings substantially. We report on the current state of the research and discuss current limitations, as well as possible directions to overcome them.

Enlightening the sun

This article presents an approach to browse collections of web pages about music artists by means of descriptive terms and multimedia content. To this end, a user interface called Three-Dimensional Co-Occurrence Browser (3D-COB) is introduced. 3D-COB automatically extracts and weights terms from artist-related web pages. This textual information is complemented with information on the multimedia content found on the web pages. For the user interface of 3D-COB, we elaborated a three-dimensional extension of the Sunburst visualization technique. The hierarchical data to be visualized is obtained by analyzing the web pages for combinations of co-occurring terms that are highly ranked by a term weighting function. We further investigated, in a first user study, different term weighting strategies to generate the visualization. A second user study was carried out to assess ergonomic aspects of 3D-COB, especially its usefulness for gaining a quick overview of a set of web pages and for efficiently browsing within this set.

Towards automatic retrieval of album covers

We present first steps towards intelligent retrieval of music album covers from the web. The continuous growth of electronic music distribution constantly increases the interest in methods to automatically provide added value like lyrics or album covers. While existing approaches rely on large proprietary databases, we focus on methods that make use of the whole web by using Googles or A9.coms image search. We evaluate the current state of the approach and point out directions for further improvements.

Towards an automatically generated music information system via web content mining

This paper presents first steps towards building a music information system like last.fm, but with the major difference that the data is automatically retrieved from the WWW using web content mining techniques. We first review approaches to some major problems of music information retrieval (MIR), which are required to achieve the ultimate aim, and we illustrate how these approaches can be put together to create the automatically generated music information system (AGMIS). The problems addressed in this paper are similar and prototypical artist detection, album cover retrieval, band member and instrumentation detection, automatic tagging of artists, and browsing/exploring web pages related to a music artist. Finally, we elaborate on the currently ongoing work of evaluating the methods on a large dataset of more than 600, 000 music artists and on a first prototypical implementation of AGMIS.