Audio Filterbank Decorrelation With Low-Latency Transfer Functions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio signal processing technologies face challenges in efficiently converting a set of input audio signals into output audio signals while achieving decorrelation and maintaining low latency.
Innovation Solution
A multi-input, multi-output audio process is implemented as a linear system within an audio filterbank, using a transfer function with a direct component and decorrelated components. This transfer function is formed from sub-band functions, and the process computes frequency-domain output audio signals by filtering frequency-domain input audio signals with complex gain functions over sub-band frequency ranges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple linear mixers are used for decorrelation processing, then decorrelation effect is improved, but latency increases
Solution Approach 1:
The patent combines multiple linear mixer operations into a single linear mixer by integrating decorrelation processing directly into the filterbank structure. The transfer function H(m,ω) incorporates both the mixing operation and decorrelation operation in one unified computational stage, eliminating the need for separate decorrelation processing stages and reducing overall system latency while maintaining the decorrelation effect.
Solution Approach 2:
The patent applies decorrelation processing as part of the frequency-domain filtering operation itself, rather than as a subsequent separate step. By incorporating the decorrelation transfer function components into the filterbank's frequency response design, the decorrelation effect is achieved during the primary signal processing operation, preventing additional latency that would result from sequential processing stages.
2Loss of time
If decorrelation processing is integrated into filterbank, then latency is reduced, but transfer function complexity increases
Solution Approach 1:
The patent segments the transfer function into distinct components: a direct component H_direct(m,ω) and decorrelated components H_decorrelate(l,m,ω). This segmentation allows the complex transfer function to be broken down into manageable parts that can be computed and implemented separately, reducing the practical complexity of implementation while maintaining the integrated low-latency structure.
Solution Approach 2:
The patent introduces component transfer functions as intermediary elements that bridge the direct mixing operation and the decorrelation operation. These component functions serve as building blocks that simplify the overall transfer function design, allowing complex decorrelation effects to be achieved through combinations of simpler, well-defined frequency-domain operations.
Data Source
AI summary
A multi-input, multi-output audio process is implemented as a linear system for use in an audio filterbank to convert a set of frequency-domain input audio signals into a set of frequency-domain output signals. A transfer function from one input to one output is defined as a frequency dependent gain function. In some implementations, the transfer function includes a direct component that is substantially defined as a frequency dependent gain, and one or more decorrelated components that have frequency-varying group phase response. The transfer function is formed from a set of sub-band functions, with each sub-band function being formed from a set of corresponding component transfer functions including direct component and one or more decorrelated components.