Contribution
Simultaneous Optimization of Absorption and Scattering Coefficients based on Differentiable Path Tracing
* Presenting author
Abstract:
Calibrating the material parameters of a model to match room acoustic simulations with measurements can be a tedious and time-consuming task. Differentiable Acoustic Path Tracing provides a method to automate this process through gradient descent. While the calibration of absorption coefficients is robust for monophonic impulse responses, the calibration of scattering coefficients is more challenging because the diffuse contributions of simultaneous reflections overlap significantly, making them difficult to distinguish. To overcome this problem, we propose the use of an Ambisonics receiver. With its additional spatial resolution, it can disentangle the diffuse components of multiple reflections, even when they overlap in time. This allows the simultaneous optimization of both absorption and scattering coefficients across multiple surfaces with only a single spatial impulse response as a reference. We evaluate the robustness of our method by varying the spherical harmonic order, absorption and scattering coefficients, number of surfaces, room geometry, and receiver position using simulated reference impulse responses.