Improved Real-Time Six-Degrees-of-Freedom Dynamic Auralization Through Nonuniformly Partitioned Convolution

Recent years have witnessed an increasing interest from the academic and industrial research community toward software for dynamic auralization and six-degrees-of-freedom (6DoF) navigation of immersive audio environments. Some existing tools rely on the convolution of source sounds with Ambisonics impulse responses (IRs) recorded in real spaces. However, despite advancements in computing power of modern central processing units, convolution remains a demanding computation to perform, especially with many channels and in real time. Moreover, efficient computation schemes often used in single-IR matrix tools have not made their way into open-source 6DoF spatial audio plugins. This paper presents MCFX-6DoFconv, an open-source 6DoF convolution plugin combining the efficient convolution engine of the MCFX-Convolver plugin with the 6DoF navigation features of SPARTA 6DoFconv, along with functional and interface improvements. Compared with the original SPARTA 6DoFconv, the proposed plugin yields a considerable increase in computing efficiency throughout a wide range of IR lengths, number of channels, and audio buffer sizes, up to a 3.7-fold improvement. This enables real-time auralization with longer IRs and multiple source rendering with more plugin instances. Moreover, the proposed plugin enables instant listener-position updates, eliminating delays up to two buffer sizes and removing the audio latency caused by internal buffering.