Sample Rate Conversion for the Audio Doppler Effect

Project Type: Student Project
Student: Joerg Mueller


This bachelor thesis discusses sample rate conversion algorithms suitable for high quality audio Doppler effects calculation to be used in the open source 3D application Blender.
The challenge is to have an algorithm that is able to dynamically change the resampling ratio over time. Apart from low order methods, an algorithm developed by Julius O. Smith is suitable for achieving this goal. The filter design necessary for this algorithm is discussed in detail. The introduced methods are then compared regarding different quality criteria. Finally, a practical experiment using the Doppler effect is implemented
using Blender.

Additional Material

In addition to the project report, the original source code of this project is available under GNU GPLv3. The results of the bachelor project are presented in a short video.

This work was conducted during the Google Summer of Code for the "3D Audio" project for Blender. A demo video containing more information about the "3D Audio" project is available here.

Mueller11_DopplerSRC.pdf7.41 MB