Frequency-Selective Audio Mixing for Natural Priority Sound Clarity

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Solution Overview

Problem

Conventional smart mixing techniques, when applied to high-quality sound systems, often result in noticeable degradation of non-priority sound, leading to an unnatural listening experience, as they prioritize clarity of priority sound over non-priority sound, especially in larger playback devices used in business settings.

Innovation Solution

The implementation of a 'vivid signal' control mechanism that dynamically adjusts gains for priority and non-priority sounds on a time-frequency plane, applying prioritized mixing only to specific important frequency bands of the priority sound while performing simple addition in other bands, thereby suppressing degradation of non-priority sound and maintaining clarity of priority sound.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If prioritized mixing is applied to enhance clarity of priority sound, then clarity of priority sound is improved, but naturalness of mixed sound deteriorates

Engineering Contradiction:
Improveclarity of priority soundVSAvoidunnatural stimulus from degraded non-priority sound
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent applies prioritized mixing selectively only to specific important frequency bands of the priority sound rather than uniformly across all frequencies. The gain adjustment is localized to frequency regions where the priority sound has significant energy, leaving other frequency bands to be mixed with simple addition. This local application of quality enhancement maintains naturalness while improving clarity where needed.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent applies prioritized mixing partially rather than completely across the entire frequency spectrum. By limiting the application to only certain frequency bands where it provides benefit, the system avoids the excessive suppression of non-priority sound that would occur with full-spectrum application, thereby maintaining overall naturalness of the mixed sound.

Inventive Principle:
Principle #16Partial or excessive action

2Measurement precision

If prioritized mixing is applied to maintain clarity of priority sound, then clarity of priority sound is maintained, but degradation of non-priority sound becomes noticeable

Engineering Contradiction:
Improveclarity of priority soundVSAvoidquality of non-priority sound
Core Design Contradiction:
Measurement precisionVSManufacturing precision

Solution Approach 1:

The patent implements frequency-selective prioritized mixing where gain adjustment is applied only to specific frequency bands corresponding to important components of the priority sound. In other frequency bands, simple addition is used to preserve the quality of non-priority sound. This localized approach ensures clarity enhancement occurs only where necessary without degrading non-priority sound in other regions.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the frequency spectrum into different bands and applies different mixing strategies to each segment. Frequency bands containing important priority sound components receive prioritized mixing, while other bands use simple addition. This segmentation allows the system to maintain clarity of priority sound in critical bands while preserving natural quality in non-critical bands.

Inventive Principle:
Principle #1Segmentation

3Device complexity

If uniform gain adjustment is applied across all frequency bands, then simplicity of mixing process is maintained, but naturalness of mixed sound deteriorates

Engineering Contradiction:
Improvecomplexity of mixing processVSAvoiddegradation of non-priority sound
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The patent transitions from uniform gain adjustment to local quality-based gain adjustment. Instead of applying the same mixing strategy across all frequencies, the system determines important frequency bands of the priority sound and applies prioritized mixing only to those specific bands. This localized approach maintains process manageability while significantly improving naturalness by avoiding unnecessary suppression in non-critical frequency regions.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3783912B1Mixing device, mixing method, and mixing program
Publication Date: 2023.08.23 HIBINO

AI summary

A mixing technique is provided that can suppress degradation of non-priority sound and output more natural mixed sound, regardless of the size and quality of a playback device. A mixing device of a first signal and a second signal on a time-frequency plane, includes a control signal generation unit configured to generate a control signal indicating whether to perform prioritized mixing that includes amplification of the first signal and attenuation of the second signal; and a gain derivation unit configured to derive a first gain for amplifying the first signal and a second gain for attenuating the second signal based on the control signal, wherein the control signal takes at least a first value and a second value different from the first value, wherein the first value is not continuous beyond a predetermined bandwidth on a frequency axis, and wherein the mixing device applies the prioritized mixing to the first signal and the second signal in response to the control signal indicating the first value, and applies simple addition to the first signal and the second signal in response to the control signal indicating the second value.