PitchTech

The PitchTech research project aims in providing high quality audio transformations implemented in Java.

Overview of the project
Software
Scientific publications
Links
Contact

The aim of the PitchTech project is to provide high quality audio effects implemented in Java. The research aspects are the following:

• High quality: How can the quality of existing audio transformations be further improved. Primarily targeted audio transformations are pitch shifting, time stretching and noise reduction.
• Low latency: How can the latency of existing audio effects be reduced.
• Parallel implementations: How can existing implementations be parallelized so that they can benefit from the future multi-core processors.
• New audio effects: Are the thousands of available audio effects the final word in audio processing theory, or is it still possible to make new ones?

• Tachyon, Quantum and Proton^(New) Audio Time Stretch: Audio time stretching softwares for Windows, Mac OS and others.
• A comparison of audio time stretching algorithms: Elastique, iZotope Radius, Tachyon, Quantum, Ircam TS2, Zynaptiq ZTX, and more...
• snd2img: A small tool to create a dummy video from an audio file.
• Preview of 4 new audio time stretching algorithms
• Tachyon Sonics: Sampled audio editor - alpha version
• PitchTech: free exotic and experimental audio effects (as VST and LADSPA plugins)
• PitchBox^(Updated): real-time voice and music transformations.
• DRC-Meter (Dynamic Range Compression Meter): small tool to measure the consequences of the loudness war on your audio files

2017

• N. Juillerat, "Audio Time Stretching with Controllable Phase Coherence" , 142^nd Audio Engineering Society Convention, AES 142^nd, 2017. (Companion page)
• N. Juillerat, B. Hirsbrunner, "Audio Time Stretching with an Adaptive Multiresolution Phase Vocoder" , IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP 2017, New Orleans, 2017. (Companion page)

2010

• N. Juillerat, B. Hirsbrunner, "Low Latency Audio Pitch Shifting in the Frequency Domain" , IEEE International Conference on Audio, Language and Image Processing, ICALIP 2010, 2010. (Download the reference implementation (command line tool + source code) in Java). (Errata)

2008

• N. Juillerat, S. Schubiger-Banz, S. M. Arisona, "A Hybrid Time and Frequency Domain Audio Pitch Shifting Algorithm" , 125^th Audio Engineering Society Convention, AES 125^th, 2008.
• N. Juillerat, S. Schubiger-Banz, S. M. Arisona, "Enhancing the Quality of Audio Transformations Using the Multi-Scale Short-Time Fourier Transform" , IASTED International Conference on Signal Processing, IASTED SIP 2008. (Companion page)
• N. Juillerat, S. Schubiger-Banz, S. M. Arisona, "Low Latency Audio Pitch Shifting in the Time Domain" , IEEE International Conference on Audio, Language and Image Processing, ICALIP 2008, pp. 29 - 35, 2008. (Errata)

2007

• N. Juillerat, S. Schubiger-Banz, S. M. Arisona, "Real-time, Low Latency Audio Processing in Java" , International Computer Music Conference, ICMC 2007, pp. 99 - 102, 2007. (Addendum)

• The DFT "à Pied": basics about the DFT and its use in audio transformations.
• Pitch Shifting with the Fourier Transform: detailed explanation of the pitch shifting audio effect using the phase vocoder.
• TarsosDSP: other cool software and research related to audio and Java.

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