Scalable Audio Decoding Gain Control for Packet-Loss Layer Changes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing communication systems face challenges in efficiently decoding signals with scalable coding, leading to significant noise due to changes in the number of layers during packet loss, and are unable to handle additional information types like text or images effectively.
Innovation Solution
A signal decoding apparatus is configured with a decoding section, an addition section, and a gain adjustment section that controls the gain based on the presence of coded information in previous and next frames, allowing for better noise suppression and handling of various information types by adjusting the gain of decoded signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If scalable coding is used to decode speech signals from partial coded information, then sound quality deterioration is suppressed under packet loss conditions, but significant noise occurs when the number of layers changes due to packet loss
Solution Approach 1:
The invention performs preliminary gain adjustment before signal output by storing gain information from previous frames and pre-calculating appropriate gain values during layer transitions. This preliminary action prevents noise occurrence rather than addressing it after the fact.
Solution Approach 2:
The invention implements feedback mechanisms by continuously monitoring the number of decoded layers and adjusting gain values based on previous frame information. The gain adjustment section uses feedback from layer count changes to dynamically control signal levels and suppress noise during transitions.
2Adaptability or versatility
If coded signals are decoded in the relay apparatus to superimpose additional information, then additional speech and audio information can be transmitted, but substantial calculation cost is required
Solution Approach 1:
The invention extracts only the necessary gain information from the coded signals during relay processing, rather than fully decoding all signals. This selective extraction approach enables additional information transmission while minimizing calculation costs at the relay apparatus.
3Reliability
If the number of layers changes during decoding due to packet loss, then packet loss resilience is achieved, but transmission bit rate suddenly changes causing significant noise
Solution Approach 1:
The invention dynamically changes the gain parameter based on the number of decoded layers and packet loss conditions. By adjusting gain values according to layer count changes, the system maintains stable output characteristics despite variations in transmission bit rate during packet loss events.
Data Source
AI summary
A signal decoding apparatus that can suppress any large unusual sounds to provide decoded signals of improved audibility even when the number of hierarchical layers to be used in the decoding process varies due to a packet loss or the like in communication utilizing a scalable encoding/decoding technique. In the signal decoding apparatus, a gain adjusting part (2308) adjusts, based on a control of a decoding control part (2301), the gain of a basic layer decoded signal outputted from a basic layer decoding part (2302). A gain adjusting part (2309) adjusts, based on a control of the decoding control part (2301), the gain of a first expansion layer decoded signal outputted from a first expansion layer decoding part (2303). A gain adjusting part (2310) adjusts, based on a control of the decoding control part (2301), the gain of a second expansion layer decoded signal outputted from a second expansion layer decoding part (2304).