Voice Signal Processing Frequency Lowering Without Duration Extension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional voice signal processing methods that lower high frequency signals to aid hearing-impaired individuals often extend the signal duration, causing interference with other voice signals, requiring additional processing to fill gaps between words.
Innovation Solution
A voice signal processing apparatus and method that lower the frequency of voice signals by dividing frequency-lowered signal frames into sub-frames, performing fade-in and fade-out processes, and overlapping adjacent sub-frames to generate an overlapping voice signal without extending the signal duration, thereby preventing interference with other voice signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the frequency of high frequency voice signals is lowered to help hearing-impaired people, then the high frequency signals become audible, but the time length of the voice signal is extended
Solution Approach 1:
The voice signal is divided into multiple frames, and each frame is further divided into sub-frames. This segmentation allows selective processing of different portions of the signal, enabling frequency lowering only where necessary while maintaining original timing elsewhere.
Solution Approach 2:
Different processing is applied to different portions of the signal. Specifically, fading is applied only to adjacent sub-frames at boundaries where frequency lowering occurs, while other portions maintain their original characteristics. This local processing prevents global time extension.
2Reliability
If the frequency of voice signals is lowered, then high frequency components become audible to hearing-impaired people, but interference occurs with other voice signals
Solution Approach 1:
The harmful overlapping portions are extracted and identified as separate entities (adjacent sub-frames). By isolating these problematic regions, the system can apply targeted fading only to these specific portions, removing the harmful interference while preserving the useful frequency-lowered signal content.
Solution Approach 2:
A fading function serves as an intermediary between the frequency-lowered signal and the original signal. This fading gradually reduces the amplitude of adjacent sub-frames, creating a smooth transition that prevents abrupt changes and eliminates interference with other voice signals.
3Ease of operation
If frequency lowering is performed without time alignment, then processing is simpler, but voice signals of other sections are affected by interference
Solution Approach 1:
The system dynamically adjusts the fading applied to adjacent sub-frames based on the specific signal characteristics. By making the fading amount adaptive rather than fixed, the system maintains simplicity while effectively preventing interference in varying signal conditions.
Data Source
Figure 1~2
Figure 3
AI summary
A voice signal processing apparatus and a voice signal processing method are provided. Each frequency-lowered signal frame included in a frequency-lowered sampling voice signal is divided into a first sub signal frame that is faded-in and a second sub signal frame that is faded-out. The first sub signal frame and the second sub signal frame that are adjacent to each other and belong to the different frequency-lowered signal frames are overlapped in order to generate an overlapping voice signal. The overlapping voice signal and the sampling voice signal are combined to generate an output signal.