Spatial Reverberation Rendering via Frequency-Band Bitstream Encoding

Solution Overview

Problem

Existing methods for spatial rendering of reverberation in augmented and virtual reality environments face challenges in achieving high-quality audio immersion while maintaining low bitstream sizes for efficient streaming and storage, leading to potential user experience issues with slow download speeds and suboptimal audio quality.

Innovation Solution

The apparatus and methods convert frequency-dependent reverberation parameters into compact bitstreams by encoding frequency band data and reverberation parameters, optimizing bitrate usage, and utilizing reverberators to render immersive audio signals based on scene and listener parameters.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If reverberation parameters are encoded in detail to maintain high audio quality, then audio immersion quality is improved, but bitstream size increases leading to slow download speeds

Engineering Contradiction:

Improveaudio qualityVSAvoiddownload speed

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The frequency spectrum is divided into multiple bands (e.g., octave bands) and reverberation parameters are encoded separately for each frequency band. This segmentation allows selective encoding of only the necessary frequency information, reducing overall bitstream size while maintaining perceptual audio quality through frequency-dependent reverberation characteristics.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system changes the representation parameters of reverberation by encoding frequency-dependent parameters (RT60, DDR for each frequency band) rather than using a single set of reverberation parameters. This parameter transformation enables compact representation of complex reverberation characteristics with reduced bitstream size while preserving audio quality.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If frequency band data is encoded to maintain spatial rendering quality, then audio immersion is improved, but bitstream size increases

Engineering Contradiction:

Improvespatial rendering qualityVSAvoidbitstream size

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The frequency spectrum is divided into multiple bands (e.g., octave bands) and reverberation parameters are encoded separately for each frequency band. This segmentation allows selective encoding of only the necessary frequency information, reducing overall bitstream size while maintaining perceptual audio quality through frequency-dependent reverberation characteristics.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system extracts and encodes only the essential reverberation parameters (RT60 and DDR) for each frequency band rather than transmitting complete frequency response data. This extraction approach retains the critical spatial rendering information while significantly reducing the quantity of data that needs to be transmitted.

Inventive Principle:

Principle #2Taking out (Extraction)

3Measurement precision

If reverberation parameters are transmitted with high precision, then audio quality is maintained, but channel capacity requirements increase

Engineering Contradiction:

Improvereverberation parameter accuracyVSAvoidchannel capacity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The system changes the representation parameters of reverberation by encoding frequency-dependent parameters (RT60, DDR for each frequency band) rather than using a single set of reverberation parameters. This parameter transformation enables compact representation of complex reverberation characteristics with reduced bitstream size while preserving audio quality.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The frequency spectrum is divided into multiple bands (e.g., octave bands) and reverberation parameters are encoded separately for each frequency band. This segmentation allows selective encoding of only the necessary frequency information, reducing overall bitstream size while maintaining perceptual audio quality through frequency-dependent reverberation characteristics.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS20250218446A1Spatial Rendering of Reverberation

Publication Date: 2025.07.03 NOKIA TECHNOLOGIES OY

AI summary

An apparatus for assisting spatial rendering in at least one acoustic environment, the apparatus including circuitry configured to: obtain at least one reverberation parameter; convert the obtained at least one reverberation parameter into at least one frequency band data; encode the at least one frequency band data; encode the at least one reverberation parameter; compare resources required to transmit the encoded at least one frequency band data and the encoded at least one reverberation parameter; generate a bitstream including: an identifier identifying the at least one acoustic environment; information defining at least one dimension of the at least one acoustic environment; and a reverberation parameter part comprising including a selection, based on the comparison, of one or more of: the encoded at least one frequency band data; and the encoded at least one reverberation parameter.