Spatial Cue Rendering Control in Multi-Channel Audio Decoding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional methods for decoding multi-object or multi-channel audio signals lack flexibility in controlling the spatial positioning of audio signals, relying on fixed decoding processes that do not allow for user-controlled or external system-directed adjustments of spatial cues.

Innovation Solution

An apparatus and method that includes a decoder and a spatial cue renderer, which decodes down-mixed audio signals and controls spatial cues such as Channel Level Difference (CLD), Channel Prediction Coefficient (CPC), and Inter-Channel Correlation (ICC) to dynamically adjust the rendering of multi-object or multi-channel audio signals based on user or external system input.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional fixed decoding processes are used for multi-channel audio signals, then decoding simplicity is maintained, but spatial positioning flexibility is lost

Engineering Contradiction:
Improvespatial positioning flexibilityVSAvoiddecoding process complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The audio signal processing is segmented into distinct functional modules: a decoder for basic signal recovery, a spatial cue renderer for positional control, and a rendering controller for parameter adjustment. This segmentation allows each module to perform a specific function, achieving spatial flexibility without overwhelming system complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system transitions from static fixed decoding to dynamic rendering by introducing controllable spatial parameters. The rendering controller adjusts spatial cue parameters (azimuth, elevation, distance) in real-time, enabling adaptive spatial positioning while maintaining a relatively simple decoder structure.

Inventive Principle:
Principle #15Dynamics

2Manufacturing precision

If spatial cues are fixed during decoding, then processing speed is maintained, but sound quality and rendering precision deteriorate

Engineering Contradiction:
Improverendering precisionVSAvoidprocessing speed
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

Spatial cue parameters are pre-calculated and stored based on audio object positions, then quickly retrieved and applied during rendering. This preliminary preparation enables high-precision spatial rendering without requiring complex real-time calculations, thus maintaining processing speed.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

A rendering controller acts as an intermediary between the decoder and spatial cue renderer, pre-processing control parameters and managing the coordination between components. This intermediary layer optimizes the workflow, ensuring both precision in spatial rendering and efficiency in processing.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Quantity of substance

If down-mixed mono or stereo signals are transmitted, then bandwidth efficiency is improved, but spatial information loss increases

Engineering Contradiction:
Improvebandwidth efficiencyVSAvoidspatial information loss
Core Design Contradiction:
Quantity of substanceVSLoss of information

Solution Approach 1:

Spatial cue information is extracted from the original multi-channel audio signal during encoding and transmitted separately as metadata alongside the down-mixed audio. This extraction preserves spatial information that would otherwise be lost in down-mixing, enabling accurate spatial rendering at the decoder.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of transmitting full multi-channel signals, the system transmits a compact down-mixed audio signal combined with copied spatial cue parameters. These parameters serve as a digital copy of the spatial positioning information, allowing high-fidelity spatial reconstruction from the down-mixed signal without requiring high bandwidth.

Inventive Principle:
Principle #26Copying

Data Source

PatentEP2629292B1Method and apparatus for control of randering multiobject or multichannel audio signal using spatial cue
Publication Date: 2016.06.29 ELECTRONICS & TELECOMM RES INST
  • EP2629292B1 patent drawingFigure 1~2
  • EP2629292B1 patent drawingFigure 3
  • EP2629292B1 patent drawingFigure 4

AI summary

The present research relates to controlling rendering of multi-object or multi-channel audio signals. The present research provides a method and apparatus for controlling rendering of multi-object or multi-channel audio signals based on spatial cues in a process of decoding the multi-object or multi-channel audio signals. To achieve the purpose, the method suggested in the research controls rendering in a spatial cue domain in the process of decoding the multi-object or multi-channel audio signals.