Simultaneous Audio Playback/capture on Multiple Interfaces, Devices and/or Networks - ADC21
Slides: https://data.audio.dev/talks/2021/synchronising-clocks/slides.pdf https://audio.dev/ -- @audiodevcon Organized and produced by JUCE: https://juce.com/ --- Synchronizing Clocks - Simultaneous Audio Playback/capture on Multiple Interfaces, Devices and/or Networks We all know how to play/capture audio from a single audio interface with our favourite audio API. But how do you play/capture audio synchronously across multiple audio interfaces, computers, local networks or even the internet? The basic principle is always the same and can roughly be split into three distinct tasks: 1. Query the current presentation/capture time of each audio interface 2. Predict and convert between presentation/capture times of different clock domains using mathematical models 3. Control the playback/capture rate of each audio interface. After a brief introduction, this talk will examine each of the above tasks in detail and how various algorithms and techniques apply to different synchronisation applications. The listener will benefit from a practical focus, by learning how various industry standards approach the problem (AVB, AirPlay, RTP, …), which APIs are available on different platforms and various practical considerations when using WiFi and/or ethernet as a transport to synchronise audio. The talk will end with a case study on how the author helped achieve less than 10μs audio playback/capture synchronisation accuracy via WiFi on the Syng Cell Alpha. --- Fabian Renn-Giles Fabian is a freelance C++ programmer, entrepreneur and consultant in the audio software industry. Before this, he was staff engineer at ROLI Ltd. and the lead maintainer/developer of the JUCE C++ framework (www.juce.com) - an audio framework used by thousands of commercial audio software companies. Before joining ROLI, he completed his PhD at Imperial College London, developing a numerical quantum optics solver with modern digital signal processing techniques and C++/MPI/OpenCL. During his academic career, Fabian regularly taught C++ to post- and undergraduate students in tutor groups. In 2005, Fabian co-founded the audio plug-in start-up Fielding DSP which specialises in real-time audio plug-ins for audio mastering. Fabian now regularly consults on various audio related software projects. Additionally, he is a regular speaker and/or workshop leader at the audio developer conference ADC. --- Streamed & Edited by Digital Medium Ltd - online.digital-medium.co.uk --- Special thanks to the ADC21 Team: Lina Berzinskas Sophie Carus Timur Doumler Derek Heimlich Josh Hodge Andrew Kirk Bobby Lombardi Top Poole Ralph Richbourg Jim Roper Jonathan Roper
Slides: https://data.audio.dev/talks/2021/synchronising-clocks/slides.pdf https://audio.dev/ -- @audiodevcon Organized and produced by JUCE: https://juce.com/ --- Synchronizing Clocks - Simultaneous Audio Playback/capture on Multiple Interfaces, Devices and/or Networks We all know how to play/capture audio from a single audio interface with our favourite audio API. But how do you play/capture audio synchronously across multiple audio interfaces, computers, local networks or even the internet? The basic principle is always the same and can roughly be split into three distinct tasks: 1. Query the current presentation/capture time of each audio interface 2. Predict and convert between presentation/capture times of different clock domains using mathematical models 3. Control the playback/capture rate of each audio interface. After a brief introduction, this talk will examine each of the above tasks in detail and how various algorithms and techniques apply to different synchronisation applications. The listener will benefit from a practical focus, by learning how various industry standards approach the problem (AVB, AirPlay, RTP, …), which APIs are available on different platforms and various practical considerations when using WiFi and/or ethernet as a transport to synchronise audio. The talk will end with a case study on how the author helped achieve less than 10μs audio playback/capture synchronisation accuracy via WiFi on the Syng Cell Alpha. --- Fabian Renn-Giles Fabian is a freelance C++ programmer, entrepreneur and consultant in the audio software industry. Before this, he was staff engineer at ROLI Ltd. and the lead maintainer/developer of the JUCE C++ framework (www.juce.com) - an audio framework used by thousands of commercial audio software companies. Before joining ROLI, he completed his PhD at Imperial College London, developing a numerical quantum optics solver with modern digital signal processing techniques and C++/MPI/OpenCL. During his academic career, Fabian regularly taught C++ to post- and undergraduate students in tutor groups. In 2005, Fabian co-founded the audio plug-in start-up Fielding DSP which specialises in real-time audio plug-ins for audio mastering. Fabian now regularly consults on various audio related software projects. Additionally, he is a regular speaker and/or workshop leader at the audio developer conference ADC. --- Streamed & Edited by Digital Medium Ltd - online.digital-medium.co.uk --- Special thanks to the ADC21 Team: Lina Berzinskas Sophie Carus Timur Doumler Derek Heimlich Josh Hodge Andrew Kirk Bobby Lombardi Top Poole Ralph Richbourg Jim Roper Jonathan Roper