Research Interests:

I am interested in developing audio processing tools that are influenced by knowledge of human audition. I have primarily worked on algorithms for musical source separation and audio effects processing.

I currently work as a research assistant in the Perception and Neurodynamics Lab at Ohio State with Dr. DeLiang Wang.

While at Northwestern, I worked with Dr. Bryan Pardo in the Interactive Audio Lab and with Dr. Gary Kendall in the Music Technology Program.

Current Projects:

Integrating monaural grouping and binaural localization for segregation of speech in reverberant environments.
Existing binaural approaches to speech segregation place an exclusive burden on localization information. These approaches can achieve excellent performance in anechoic conditions but degrade rapidly in realistic environments where room reverberation corrupts binaural cues. In this project we propose integrating monaural grouping and binaural localization to achieve sequential organization and segregation of speech in reverberant environments.

Resolving overlapping harmonics in monaural music separation.
In this project we explore a novel method of estimating sinusoidal parameters (amplitude and phase) of instrument harmonics that overlap with eachother in time-frequency space. We utilize the principle that an instrument's harmonics tend to have correlated amplitude envelopes and that changes in phase can be predicted from a signal's fundamental frequency. With these two observations we are able to determine the parameters of overlapped harmonics using a least-squares estimation framework. Our results indicate that this approach achieves significant performance improvements over state of the art monaural music separation systems.
Audio Examples

Estimating the number of instruments in stereo music recordings
Numerous source separation algorithms assume that the number of source signals are known in advance. An algorithm to accurately estimate the number of signals in a recording, or at least provide a rough estimate of the ensemble size in music recordings would greatly facilitate music separation and music information retrieval.

Publications:

J. Woodruff and D. L. Wang. "Sequential organization of speech in reverberant environments by integrating monaural grouping and binaural localization," submitted to IEEE Trans. Audio, Speech and Lang. Proc.

J. Woodruff and D. L. Wang. "Integrating monaural and binaural analysis for localizing multiple reverberant sound sources," submitted to ICASSP 2010.

Y. Li, J. Woodruff and D. L. Wang. "Monaural musical sound separation using pitch and common amplitude modulation," in IEEE Trans. Audio, Speech and Lang. Proc., vol. 17, no. 7, pp. 1361-1371, 2009. [.pdf]

J. Woodruff and D. L. Wang. "On the role of localization cues in binaural segregation of reverberant speech," in Proc. ICASSP, 2009. [.pdf , poster]

J. Woodruff, Y. Li and D. L. Wang. "Resolving overlapping harmonics for monaural musical sound separation using pitch and common amplitude modulation," in Proc. ISMIR, 2008. [.pdf , poster]

J. Woodruff and B. Pardo. "Using pitch, amplitude modulation and spatial cues for separation of harmonic instruments from stereo music recordings," in EURASIP J. Adv. Signal Proc., vol. 2007. [.pdf]

J. Woodruff, B. Pardo and R. Dannenberg. "Remixing stereo music with score-informed source separation," in Proc. ISMIR, 2006. [.pdf]

A. D. Shamma, B. Pardo and J. Woodruff. "MusicStory: an autonomous, personalized music video creator," in Intelligent Music Information Systems: Tools and Methodologies, J. Shen, J. Shepherd, B. Cui, L. Liu, Eds., 2007. [link]

J. Woodruff and B. Pardo. "Active source estimation for improved source separation," Technical Report, Northwestern University, Dept. of Electrical Engineering and Computer Science, NWU-EECS-06-01, 2006. [.pdf]