ISE599: Engineering Approaches to Music Perception and Cognition

Spring 2004 Daniel J. Epstein Department of Industrial and Systems Engineering
University of Southern California
Instructor: Elaine Chew

Guitar Scores Interpretation - Transforming Audio into Guitar Tab Scores . Ching-Hua Chuan and Kevin Zhu [ website ]
Nowadays, many guitar players spend a lot of time searching on the Internet to find guitar tabs for pop songs. Many magazines and books make money on selling these guitar scores. Currently, the scores available online are those translated by professional guitarists. In this project, we try to design a system to generate playable guitar scores from audio. This system contains two major parts. First we use signal-processing technique to identify the frequency/pitch of each input note. Then, based on the pitch and timing of each note, we apply an algorithm to generate guitar tabs which are the most playable ones for amateurs. We take audio in wave format as input, which is the most common music format. Experiments are conducted by having some pop guitar songs as examples to evaluate the performance of our system. Discussions are also provided on these experiments.

An Experiment in similarity using the Spiral Array Model . Joann Emmanuel [ description | src ]
This is a computational approach to assessing similarity between a theme and variations. Mozart used the theme from a popular children's song, "Twinkle Twinkle Little Star" to write his variations on a theme. How similar are these variations to the theme? The Spiral Array model constructs how each variation establishes tonality in geometric space (the center of effect). This underlying structure for the variations should be similar to the underlying structure of the theme. For this experiment, three methods of generating the center of effects were used. A correlation method identical to the "corel" command in humdrum is used to measure the similarity between the theme and each variation. Computations conducted using Matlab.

Visually Interpreting Bach . Daniel Han [ narrative | executables ]
In 1979, Longuet-Higgins and Steedman described in Interpreting Bach an algorithm to determine the key of a Bach's fugues. This application implements that algorithm in a multimedia fashion with visual and audio features. The algorithm utitlized a 2-D grid with different shapes to determine the key. My application allows the user to follow the steps of the algorithm visually with the different shapes displayed as the user inputs various notes. Furthermore, MIDI output is also incorporated so the user can hear the notes as the algorithm is running.

Ratio Representation of Harry Partch's "Monophonic" Resources . Brian Harlan and Arun Chirambaram [ website ]
American, microtonal composer Harry Partch (1901-1974) is recognized by music historians as a crucial figure in the development of 20th-century American music, yet serious studies of his music are rarely undertaken. The reason for this is not due to the uniqueness of his musical resources, which includes a division of the octave into forty-three tones, and an orchestra of his own fabrication. Rather, analysis of his compositions is primarily made difficult by Partch's idiosyncratic musical notation. Since his notation was designed mainly for performance, his scores are a disconnected amalgamation of instrumental parts, each of which is notated in a tablature specific to its instrument. Nearly every instrument is notated differently, and thus each instrumental line makes use of different symbols. The system is further complicated by Partch's preference for ratio representation in place of common practice note names. And finally, because his forty-three tones do not fall easily onto the five-line staff, Partch often disregards the use of heightened notation. The result is a complex symbolic jumble that is only decipherable after significant familiarization with his theoretical explainations. In order to make Partch's compositions more accessible to a wider population a program was written that represents ratios in a heightened relationship, and translates them into frequencies for audio output.

Team Bre . Ananda Jacobs and Beran Pacaci [ website ]
The Team-bre project aims to implement the expressive reproduction capabilities of the Director Musices program to explore different timbres. The theory behind the project is that timbre plays an important role in expressivity. Players of different instruments were hypothesized to employ different types of expression rules. To demonstrate, two cello players, clarinet players, and trumpet players were asked to play a Chopin Etude (Opus 10 No. 3). Director Musices was then used to try and approximate these performances. The aim was to generate instrument-specific rule sets. The rules for one instrument were then applied to the nominal MIDI versions of other instruments. It was hypothesized that listeners would prefer the version that used the original instrument rather than an b expression parameters are applied across different instruments, listeners would not rank them equally. This would show that timbre plays a role in how listeners perceive the expressive quality of music.

Tracking and perceiving beats in expressive performances . Jie Liu
This project is the implementation of the paper of Edward Large. One MIDI reading and writing module in ESP with MFSM is used to generate different performances of one piece of music. Then the model in the paper is used to track the beats in those different performances and the performance timing is also tested. The experimental results in the paper are also tested in the project.

AMIT - A MIdi Thing . Amit Singh
Amit is a tool to make a MIDI file from a MuseData source file. MuseData is an ASCII format for representing music. This program reads a MuseData file and converts it to a MIDI file.

FAMIRT, Finding A Motif using Inversion, Retrograde, and Transposition . Carley Tanoue
FAMIRT, Finding A Motif using Inversion, Retrograde, and Transposition, is a computational approach to finding motifs in a given piece. Taking in a subject piece in MIDI format, the user selects a segment to be denoted as the "motif" for which the program parses through each segment of the piece searching for each instance of inversion, retrograde, inversion-retrograde, and transposition of the selected "motif." A colorful hole-punch score displays the results.
Generation of Vibrato in Expressive Performances in MIDI . Aaron Yang [ description | executable ]
Vibrato, the modulation of pitch, is important to the performance of expressive music. A difficulty for MIDI is the fact that vibrato and other musically expressive techniques are not easily modeled symbolically. As a result, most symbolic MIDI files lack expressive techniques such as vibrato. In this project, I create a program which will attempt to add vibrato to MIDI files.

Updated 27 April 2004.