YOUNG CHANG RESEARCH AND DEVELOPMENT
INSTITUTE (Kurzweil Music Systems)
Senior Software Engineer

September 2007 – Present

Main Roles:
Embedded programmer using C and C++ for the PC3 synthesizer/controller series.
Architect for the controller system in the new generation of products.

Sequencer:
Designed and implemented a modular sequencer architecture:
- Capabilities for many sequencers running simultaneously.
- Cross-sequencer synchronization, triggering, etc. (riffs in the new Kurzweil products)
- Cross platform code: embedded, linux, windows, mac.
- Embedded UI for sequence creation and editing.

Editor/UI:
Principal Architect for the New Editor System
- Cross platform: embedded, windows, linux, mac.
- Separation between UI elements and parameters using a remote addressing system.
- Implemented the whole navigation, rendering engine for the embedded system.
- using an external (custom created) WYSIWYG editor to create all the UI.
- Created and tested the new concepts with a remote virtual display and control system,
capable of fully controlling PC3 series of synthesizers using TPC/IP or serial
communication.

Low Level Tools:
- Rewrote all the dynamic memory (malloc) functions.
- Tools to measure the performance of the system
- Tools for detecting memory leaks, bad memory usage practice, etc.

Audio Analysis:
- Use of high resolution spectral analysis and parameter estimation to find similar sounds in
synthesizers.
- Genetic Programming tools to create new sounds by example.

GROOVE MOBILE Audio Scientist
(formerly Chaoticom)

November 2001 – August 2007

Hampton Falls, NH; Andover, MA.; Bedford MA

Work in a small scientific team researching and developing algorithms for high quality low bitrate audio encoding.

• Development and implementation of:
• Custom psychoacoustic models for analysis and synthesis of audio and music signals.
• Various joint stereo (and multichannel) algorithms for sound compression.
• Integer FFT algorithms.
• High resolution analysis and synthesis
• Representation of transient events by means of modeling of the phase.
• Many ‘in-house’ tools for debugging of Matlab and C++ code.
• GUI for audio encoding software, management of audio tracks.
• ID3 tag editor
• Tools for benchmarking of audio encoders
• Preprocessing tools (level, eq, dynamics) for automatic content encoding.
• Detection, isolation and correction of various audio artifacts by means of critical listening.
• Sound quality assessment.
• Development of guidelines for perceptual listening tests.
• Mentoring and supervision of graduate level interns.

Development and implementation of high quality low bitrate video encoding altgorithms.

• Adaptation and further research of audio analysis techniques into multiple dimensions tailored for video applications.

Development and implementation of “music recommendation” system.

• Development of an efficient real-time sparse matrix library capable of handling millions of cross referenced items.
• Research and implementation of correlation and music similarity metrics.

Design and implementation of the “Online Community” system.

• Profile based online community for networking.
• Focused on playlist sharing, profile matching based on multiple criteria (profile, playlists, artist, genre)
• Modular design: webservice backend + presentation layer (html/wap/proprietary)

MIT MEDIA LAB Research Assistant

September 1999 – September 2001

Cambridge, MA

• Designed and implemented a full Genetic Programming environment to evolve Sound Synthesis Algorithms. (AGeSS system)
• Syntax and grammar for manipulation of Sound Synthesis Algorithms (SSA) as topologies
• Generation mechanism to create valid SSAs
• Development and integration of a psychoacoustic algorithm to evaluate the subjective performance of various SSAs
• Setup for controlling multiple DVD players synchronized for the "in place performers" exhibition.
• Developed a system to use Cellular Automata as sound synthesizers, and a method to train the system by using psychoacoustic models.
• Developed a sound classification system by use of Cepstral coefficients grouping.
• Involved in the definition of a Melody Contour descriptor proposed to the MPEG-7 Standards Committee.
• Several talks and publications about the uses of Genetic Programming for sound synthesis and audio processing.
• Presentation, demos and talks about the research performed at the Machine Listening group at MIT Media Lab (netsound, structured audio, instrument recognition, voice modeling, music modeling).

UNIVERSITY OF MIAMI Teaching Assistant
School of Music

May 1998 – May 1999

Coral Gables, FL

• Designed and implemented an audio watermarking algorithm capable of embedding an imperceptible stream of bits in audio signals.
• Designed and implemented psychoacoustic models of human hearing mechanism.
• Explored the use of spread spectrum techniques to encode bit streams in audible frequency range signals.
• Designed and implemented a system for voice removal from audio recordings by using adaptive filtering.
• Designed a test for subjective evaluation of perceived audio quality and artifact detection of psychoacoustically modified audio.
• Supported and enhanced the Real Audio system for internet broadcasting of live concerts. Added automatic scheduling, logging and archiving of concerts. Upgraded and configured system to use the latest available low bitrate encoders.
• Served as Network Administrator for the school of music computer network. Responsible for: main server, web server, and two audio computer labs.

LA FACTORIA Music Engineer, co-owner

December 1996 – August 1997

Medellin, Colombia

• Studio for production, recording, mixing, mastering and post-production.

VIA MIDI Music Engineer, owner

June 1994 – August 1997

Medellin, Colombia

• Taught courses in music sequencing, audio production, home studio recording, audio processing, and general use of computer for music production.
• Consultant for multiple professional audio setups.
• Designed, implemented and manufactured MIDI interfaces for pc computers.