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Digital Libraries and Music. Jon Dunn SLIS L631 Music Librarianship Seminar April 7, 2003. Outline. Digital Libraries Music content Variations Variations2 Special topics: Music information retrieval Open Archives Initiative. What is a digital library?.
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Digital Libraries and Music Jon Dunn SLIS L631 Music Librarianship Seminar April 7, 2003
Outline • Digital Libraries • Music content • Variations • Variations2 • Special topics: • Music information retrieval • Open Archives Initiative
What is a digital library? • DL as collection/information system • “a collection of information that is both digitized and organized” -- Mike Lesk, National Science Foundation • “networked collections of digital text, documents, images, sounds, scientific data, and software”-- President’s Information Technology Advisory Council report • DL as organization: • “an organization that provides the resources, including the specialized staff, to select, structure, offer intellectual access to, interpret, distribute, preserve the integrity of, and ensure the persistence over time of collections of digital works so that they are readily and economically available for use by a defined community or set of communities”-- Digital Library Federation
Applications of music DLs • Education • Electronic reserves • Online instructional tools • Research • Better access to special collections • New capabilities for analysis, searching • Commercial • Professionals • E.g. music/film/video production • Consumers • Online music catalogs, digital distribution
What is a music digital library? • What does it contain? • How is this content acquired? • How is this content accessed? • How can the content be used once located? • What is the purpose? • Who are the users? • How is content protected?
Music DL features • Content • Selection, digitization, storage, delivery • Metadata (cataloging) • Search capabilities • for content and metadata • Interfaces • User interfaces, programmatic interfaces • Access control
Basic Representations of Music Audio (e.g., CD, MP3): like speech Time-stamped Events (e.g., MIDI file): like unformatted text Music Notation: like text with complex formatting
Content Formats • Audio • MIDI • Scores • Images • Structured file format • (Video)
Digital audio • Sampling • Sample rate, sample size, number of channels • Compression • Perceptual audio coding • File formats • Standards
Digital audio file formats • Uncompressed –all basically the same • WAV - Microsoft/IBM • AIFF - SGI/Apple • AU/SND - NeXT/Sun • Compressed • MPEG-1 layers 1-3, MPEG-2 AAC • RealAudio, Windows Media, QuickTime • Each supports various compression options
Digital audio file sizes • Uncompressed audio • 44.1 kHz, 16 bit, stereo (CD quality) • 650 MB for one hour • 1.4 Megabits/second • Compressed • MP3: 58 MB for one hour, 128 Kilobits/second • AAC: 29 MB for one hour, 64 Kilobits/second • RealAudio, Windows Media Audio, QuickTime Qdesign Music: down to 20 Kilobits/second or less
Digital Audio audio sampling quantization noise Barlow, Multimedia Systems, p. 77.
CD Audio • Sample rate: • 44.1 kHz (44,100 samples/second) • Sample size: • 16 bits • Number of channels: • 2 (stereo) • Bitrate • 44100 samples/second * 16 bits/sample * 2 channels = 1.4112 megabits/second (plus file format/network overhead)
Masking Effect Barlow, Multimedia Systems, p. 73.
Digital audio delivery • Delivery options • Download • Streaming • e.g. RealAudio, Windows Media, QuickTime Streaming • Encrypted download • e.g. LiquidAudio, a2bmusic, Windows Media
Scores • Score image • File format: TIFF, JPEG, GIF, PDF, … • Resolution • Grayscale vs. bitonal (black and white) • Score notation • Many proprietary formats • No common standard
Attributes of notated musical information • Pitch • Duration • Tempo • Dynamic level • Articulation • Part (sometimes implying timbral definition) Selfridge-Field, Beyond MIDI, p. 9.
Difficulties in representing CMN • Grammar of CMN is open-ended • Which is more critical: graphical appearance or semantic meaning? • Much left open to interpretation • Style differences, e.g. interpretation of rhythms
Music Notation File Formats • www.music-notation.info lists over 50 different music notation formats, most for CMN
MIDI • Musical Instrument Digital Interface • Originally a hardware interface spec • Communication of real-time events between musical devices • Standard MIDI File (SMF) • Stores time-stamped MIDI event information • e.g note on/off, key pressure, aftertouch, pitch bend, control change, program change. • Each event accompanied by parameters • e.g. note on includes pitch, duration, dynamic range • Spec maintained by industry group • MIDI Manufacturers’ Assocation
Limitations of MIDI • MIDI does not represent many musical attributes • Graphical notation elements • Rests, stem direction, enharmonic distinctions, staff systems, page layout, etc. • Sound elements • Timbre, full stylistic expression • Extensions exist but not widely used
Creating Notation Content • Transcription • Music notation editor • ASCII data entry • Recognition • OMR: Optical Music Recognition
OMR: Optical Music Recognition • Commercial packages • Musitek MidiScan/SmartScore • Version included with Finale • Neuratron PhotoScore • Version included with Sibelius
Here's the original: Scanned into Finale: Only 5 easy edits needed. Taken from http://www.codamusic.com/finale/scanning.asp OMR: A long way from OCR
OMR: Optical Music Recognition • Research projects • CANTOR • University of Waikato, New Zealand • Adaptive OMR • Johns Hopkins University, USA • Example:http://mambo.peabody.jhu.edu/omr/demo/ • others: • http://www.cs.waikato.ac.nz/~davidb/omr/
Score Images • Scanned images still useful • Historical editions, manuscripts • Preservation, improving access • Impracticality of large-scale OMR • Music presents challenges for scanning
Variations • Digital library of music sound recordings and scores • Online since 1996 • Accessible in Music Library and other select locations - copyright • Used daily by large student population
Original Concept • Burroughs and Fenske, 1990 • VARIATIONS name • Theme and Variations • Variety of information formats for music • Networked access for the music student or scholar to sound recordings, scores, textual materials, video recordings
Focus on Audio • High demand portion of collection • Fragile formats • Lack of previous work; uniqueness
Focus on Audio Reserves • Half of sound recording use from reserves • Problems with existing practices • Cassette tape dubs, analog distribution systems • Concentrated use of a few items at any given time
Variations System • Digitization • Storage • Access
Design and Development • Developed by Music Library with assistance from UITS and Library Information Technology • Integrate rather than develop from scratch • Partnership with IBM • Funding: School of Music, Libraries, UITS, IBM • Online in April 1996
Digitization • Formats • Analog: LP, cassette tape, reel-to-reel tape • Digital: CD, DAT • Capture at CD quality • 44.1 kHz, 16 bit, stereo, 700MB for one hour • Compress to MPEG-1 layer 2 (“MP2”) • 200 MB for one hour • Create “track file”
Digitization Hardware and Software • Windows PCs • Sound capture card • Microtest Disc-to-Disk CD capture software • Sonic Foundry Sound Forge XP audio editor
Storage • Tivoli Storage Manager software • IBM RS/6000 AIX server • IBM Tape Library Dataserver • Contains three tape drives • 10 terabyte (10,000 gigabyte) capacity
IBM 3590E tapes: 20GB each
Access • Discovery • How does the user find the desired recording? • Playback • How is audio delivered to the user? • How does the user navigate within a given recording?
Collection • Currently: 6900 titles, 8000 hours of audio • 5.6 TB uncompressed • 1.6 TB compressed • Opera, songs, instrumental music, jazz, rock, world music
Discovery • Varies based on purpose of access • Reserves • Course reserve lists • Faculty-created course home pages (incl. Oncourse) • General use • Links from IUCAT library catalog(856 fields in MARC bib records)
Playback • Streaming server • IBM RS/6000, 150 GB disk • IBM VideoCharger server software • Software to connect VideoCharger with TSM (locally written) • Client • IBM VideoCharger client software • Variations Player (locally written) • Navigation via track files
Network • Originally ATM • 25/100/155 megabits per second • Now switched Ethernet • 10/100/1000 megabits per second • Variations audio stream requires 384 kilobits/second • Up to 150 streams
Variations2 • Four-year project • Started October 1, 2000 • Funding from NSF and NEH through Digital Libraries Phase 2 (DLI2) program • Large interdisciplinary team of investigators • Faculty: Music, Information Science, Law, Computer Science • Librarians and technologists: Libraries, University Information Technology Services • Bloomington and Indianapolis campuses
Project goals • Establish a digital music library testbed system supporting multiple formats: audio, video, score images, score notation • Develop multiple interfaces for specific user applications in the music library and the classroom • Conduct research in metadata, usability, copyright, and networking
Partners: “Satellite Sites” • United States • University of Illinois at Urbana-Champaign • University of Massachusetts at Amherst • Northwestern University • United Kingdom • Kings College - London • Loughborough University • University of Oxford • Japan • Waseda University • Evaluation…potential for co-development
The Variations2 System • Integrated access to music in all formats • Digital audio recordings • Score images • Score notation • Video • Delivery to wide range of users • Faculty: teaching, course design, research • Students: coursework, independent study • Music librarians, other library users • Extensible • Multiple user interfaces • Staged development