Inter-channel High-band Audio Encoding via Spectral Parameters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio encoding and decoding technologies for multiple high-band audio signals result in user experience degradation due to the lack of transmission of high-band portion data, leading to discrepancies between input and output audio signals.
Innovation Solution
A system and method for encoding and decoding multiple high-band audio signals using a downmixing algorithm to generate Mid and Side channels, followed by encoding spectral parameters, and utilizing a decoder to generate synthesized high-band audio signals based on received parameters, thereby approximating the original high-band portions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If data corresponding to the high-band portion of the side signal is not transmitted to reduce the number of bits transmitted, then transmission efficiency is improved, but the accuracy of the reconstructed audio signal deteriorates
Solution Approach 1:
The patent introduces an intermediary parameter (spectral shape parameter) that captures the essential characteristics of the high-band side signal without transmitting the full signal data. This spectral shape parameter acts as a mediator that allows the decoder to reconstruct the high-band side signal accurately from the mid signal, thus reducing transmission bits while maintaining reconstruction accuracy.
Solution Approach 2:
The patent transforms the high-band side signal into a different parameter representation (spectral shape parameters) that can be transmitted efficiently. By changing the parameter form from raw audio samples to spectral characteristics, the system achieves compact representation that preserves the essential information needed for accurate reconstruction.
2Quantity of substance
If the high-band portion of the side signal is not transmitted, then transmission bandwidth is reduced, but the quality of the output audio signal deteriorates
Solution Approach 1:
The spectral shape parameter serves as an intermediary that conveys the essential spectral characteristics of the high-band side signal. This intermediary parameter enables the decoder to synthesize the missing high-band side signal components, maintaining output quality while reducing transmission bandwidth requirements.
Solution Approach 2:
The patent creates a simplified copy or representation of the high-band side signal in the form of spectral shape parameters. This copied representation contains the necessary information to reconstruct the original signal characteristics, allowing accurate reproduction with reduced data transmission.
3Quantity of substance
If spectral parameters are encoded and transmitted instead of full audio signals, then data transmission efficiency is improved, but the complexity of the encoding and decoding process increases
Solution Approach 1:
The patent extracts only the essential spectral shape parameters from the full audio signal for transmission. By taking out only the critical characteristics needed for reconstruction rather than transmitting the complete signal, the system achieves efficient data transmission while keeping the encoding and decoding processes manageable.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A device includes an encoder and a transmitter. The encoder is configured to generate a first high-band portion of a first signal based on a left signal and a right signal. The encoder is also configured to generate a set of adjustment gain parameters based on a high-band non-reference signal. The high-band non-reference signal corresponds to one of a left high-band portion of the left signal or a right high-band portion of the right signal as a high-band non-reference signal. The transmitter is configured to transmit information corresponding to the first high-band portion of the first signal. The transmitter is also configured to transmit the set of adjustment gain parameters corresponding to the high-band non-reference signal.