Two-Microphone 3D Acoustic Field Capture and Transcoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current three-dimensional sound capture systems require at least three channels for capture and transmission, limiting their use due to bulk, cost, and compatibility with existing two-channel audio equipment and formats.
Innovation Solution
A system using two microphones with appropriate processing to analyze sound signals in the frequency domain, allowing for the capture and transcoding of two-dimensional or three-dimensional acoustic fields, suitable for immersive listening, using only two channels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If three-dimensional sound capture systems use at least three channels for capture and transmission, then the capture quality and spatial accuracy are improved, but the bulk, cost, and compatibility with existing two-channel audio equipment deteriorate
Solution Approach 1:
The patent extracts only the essential spatial information (direction of arrival, energy, phase) from the full multi-channel acoustic field using just two microphones. By taking out only the necessary parameters for spatial perception rather than capturing the complete acoustic field, the system achieves 3D spatial accuracy with reduced channel count, directly resolving the contradiction between measurement precision and device complexity
Solution Approach 2:
The patent creates a simplified copy of the spatial acoustic information using two channels instead of three or more. By encoding directional and spatial data into stereo signals that can be decoded to reconstruct the spatial field, the system replicates the essential 3D capture functionality with fewer resources, maintaining spatial accuracy while reducing device complexity
2Device complexity
If binaural recording systems use two microphones to reproduce physical phenomena around a listener's head, then the device complexity is reduced, but the adaptability to different listener characteristics and head rotation deteriorates
Solution Approach 1:
The patent creates a universal system that can adapt to different listener characteristics and head orientations through software processing rather than requiring physical customization. The two-microphone setup with electronic directional analysis and spatial encoding can be configured for different binaural rendering scenarios, making the system universally adaptable to various listener anatomies and head positions without changing the physical microphone arrangement
Solution Approach 2:
The patent replaces the mechanical/biological variability of different human heads with an electronic processing system. Instead of requiring physical binaural microphones matched to specific listener anatomy, the system uses two microphones with electronic directional analysis and binaural rendering algorithms that can be adjusted for different listener characteristics, substituting mechanical adaptation with electronic flexibility
3Device complexity
If two-microphone systems are used for two-dimensional stereophonic capture, then the bulk and cost are reduced, but the ability to capture three-dimensional acoustic space deteriorates
Solution Approach 1:
The patent adds the third spatial dimension to two-microphone stereophonic capture by implementing directional analysis that extracts elevation and azimuth information from the stereo signals. Through frequency-domain processing and phase analysis, the system recovers 3D spatial data from what would traditionally be limited to 2D stereo, enabling transcoding to immersive formats without adding physical microphones
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables reduced bulk and cost, flexible placement on mobile devices, and compatibility with stereophonic content, facilitating direction detection and phase analysis at various stages of the audio production chain.
Implementation Method 1
a first omnidirectional button (1302) placed in position (xoffset, 0, 0)... said first button (1302) being of omnidirectional directivity
Implementation Method 2
a second button (1303) placed in position (xoffset, 0, 0)... said second button (1303) being of cardioid directivity
Data Source
AI summary
Capturing, encoding and transcoding an acoustic field, such as a three-dimensional acoustic field, comprising a device made up of two microphones, directional analysis and encoding means of said acoustic field, and optionally means for transcoding said acoustic field.