Resynthesis of Spatial Room Impulse Response Tails With Anisotropic Multi-Slope Decays

Hold, Christoph; McKenzie, Thomas; Götz, Georg; Schlecht, Sebastian J.; Pulkki, Ville

doi:10.17743/jaes.2022.0017

Cited by 9 publications

(6 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The term diag N (•) formalizes µ times repeating the νth axisymmetric beamformer weight, with µ and ν being the spherical harmonic (SH) degree and order, respectively. We employ a spherical Butterworth beamformer [52, Table 3.1], which exhibits a great front-to-back-separation and has been successfully used in room acoustic analysis and Ambisonic RIR processing applications [53], [54]. The axisymmetric weights of the spherical Butterworth beamformer are given by…”

Section: B Room Transition Along a Straight Line: Spatial And Directi...mentioning

confidence: 99%

Common-Slope Modeling of Late Reverberation

Götz,

Schlecht,

Pulkki

2023

IEEE/ACM Trans. Audio Speech Lang. Process.

Self Cite

View full text Add to dashboard Cite

The decaying sound field in rooms is typically described by energy decay functions (EDFs). Late reverberation can deviate considerably from the ideal diffuse field, for example, in multiple connected rooms or non-uniform absorption material distributions. This paper proposes the common-slope model of late reverberation. The model describes spatial and directional late reverberation as linear combinations of exponential decays called common slopes. Its fundamental idea is that common slopes have decay times that are invariant across space and direction, while their amplitudes vary across both. We explore different approaches for determining the common slopes for large EDF sets describing different source-receiver configurations of the same environment. Among the presented approaches, the k-means clustering of decay times is the most general. Our evaluation shows that the common-slope model introduces only a small error between the modeled and the true EDF, while being considerably more compact than the traditional multi-exponential model. The amplitude variations of the common slopes yield interpretable room acoustic analyses. The common-slope model has potential applications in all fields relying on late reverberation models, such as source separation, dereverberation, echo cancellation, and parametric spatial audio rendering.

show abstract

Section: B Room Transition Along a Straight Line: Spatial And Directi...mentioning

confidence: 99%

Common-Slope Modeling of Late Reverberation

Götz,

Schlecht,

Pulkki

2023

IEEE/ACM Trans. Audio Speech Lang. Process.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The early reflections are interpolated and equalised at different directions on the sphere by using a process of beamforming and reconstruction, as detailed further in [27,28]. For this, the measured SH domain responses are analysed with a set of max-r E beams directed to a dense set of L uniformly arranged directions on a t-design with steering angles Θ Θ Θ t [29],…”

Section: Early Reflectionsmentioning

confidence: 99%

“…An equalisation curve is then calculated by linear interpolation of each ERB band target RMS, between 20 Hz and 20 kHz. After the directionally equalised responses for every directional response in h (EQ) are obtained, they are brought back in the SH domain [28] using…”

Section: Early Reflectionsmentioning

confidence: 99%

Auralization of Measured Room Transitions in Virtual Reality

McKenzie¹,

Meyer-Kahlen²,

Hold³

et al. 2023

J. Audio Eng. Soc.

View full text Add to dashboard Cite

To auralise a room's acoustics in six degrees-of-freedom (6DoF) virtual reality (VR), a dense set of spatial room impulse response (SRIR) measurements is required, so interpolating between a sparse set is desirable. This paper studies the auralisation of room transitions by proposing a baseline interpolation method for higher-order Ambisonic SRIRs and evaluating it in VR. The presented method is simple yet applicable to coupled rooms and room transitions. It is based on linear interpolation with RMS compensation, though direct sound, early reflections and late reverberation are processed separately, whereby the input direct sounds are first steered to the relative direction-of-arrival before summation and interpolated early reflections are directionally equalised. The proposed method is first evaluated numerically, which demonstrates its improvements over a basic linear interpolation. A listening test is then conducted in 6DoF VR, to assess the density of SRIR measurements needed in order to plausibly auralise a room transition using the presented interpolation method. The results suggest that, given the tested scenario, a 50 cm to 1 m inter-measurement distance can be perceptually sufficient.

show abstract

“…The term diag N (•) formalizes µ times repeating the νth axisymmetric beamformer weight, with µ and ν being the spherical harmonic (SH) degree and order, respectively. We employ a spatial Butterworth beamformer [61, Table 3.1], which exhibits a great front-to-back-separation and has been successfully used in room acoustic analysis and Ambisonic RIR processing applications [56], [62]. The axisymmetric weights of the spatial Butterworth beamformer are given by…”

Section: B Room Transition Along a Straight Line: Spatial And Directi...mentioning

confidence: 99%

Common-slope modeling of late reverberation

Götz¹,

Schlecht²,

Pulkki³

2022

Preprint

Self Cite

View full text Add to dashboard Cite

<p>The decaying sound field in rooms is typically described in terms of energy decay functions (EDFs). Late reverberation can deviate considerably from the ideal diffuse field, for example, in scenes with multiple connected rooms or non-uniform absorption material distributions. This paper proposes the common-slope model of late reverberation. The model can be used to describe spatial and directional late reverberation variations as linear combinations of exponential decays with fixed decay times. Its fundamental idea is to determine a set of common decay times that is representative of multiple EDFs. Consequently, all spatial and directional EDF variations are described solely with amplitude changes of the respective decaying exponentials. After deriving the common-slope model, we explore different approaches for determining the common decay times for large EDF sets, whose EDFs describe different source-receiver configurations of the same environment. Among the presented approaches, the k-means clustering of decay times is the most general. Our evaluation shows that the common-slope model introduces only a small error between the modeled and the true EDF, although the common-slope model is considerably more compact than the traditional multi-exponential model. Due to its compactness, the common-slope model yields interpretable room acoustic analysis results. The common-slope model has potential applications in all fields relying on late reverberation models, such as source separation, dereverberation, echo cancellation, and parametric spatial audio rendering.</p>

show abstract

Resynthesis of Spatial Room Impulse Response Tails With Anisotropic Multi-Slope Decays

Cited by 9 publications

References 23 publications

Common-Slope Modeling of Late Reverberation

Common-Slope Modeling of Late Reverberation

Auralization of Measured Room Transitions in Virtual Reality

Common-slope modeling of late reverberation

Contact Info

Product

Resources

About