Audio Decoder Single-Pass Adaptive Hybrid Transform
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio decoding algorithms require multiple passes over audio blocks to decode data, consuming significant computational resources due to the need to read and examine data twice for each channel, which can be inefficient, especially for complex bit streams like those compliant with ATSC Standards.
Innovation Solution
A method that decodes a frame of an encoded digital audio signal in a single pass by examining the encoded data in order by block, determining whether adaptive hybrid transform processing was used, and applying appropriate transforms to obtain spectral coefficients and hybrid transform coefficients, thereby reducing the need for redundant calculations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple passes over audio blocks are used to decode data, then decoding accuracy is maintained, but computational resources are significantly consumed
Solution Approach 1:
The patent applies preliminary action by performing a first pass over the audio blocks to read and examine data structure information before the actual decoding process. This preliminary examination allows the decoder to identify which blocks require adaptive hybrid transform processing and prepare appropriate transformation matrices in advance, so that the second pass can proceed efficiently with pre-computed parameters, reducing redundant calculations and computational resource consumption during the main decoding operation.
2Reliability
If multiple passes over audio blocks are used to decode data, then complete decoding is achieved, but processing time is increased
Solution Approach 1:
The patent performs preliminary actions in the first pass by examining data structure information and identifying blocks requiring adaptive hybrid transform processing. This preparation phase enables the second pass to execute decoding operations with pre-computed transformation matrices and known processing requirements, thereby reducing the time needed for actual decoding while ensuring complete and accurate reconstruction of the audio signal.
3Loss of information
If adaptive hybrid transform processing is applied, then spectral coefficients are obtained, but additional computational steps are required
Solution Approach 1:
The patent applies local quality by selectively applying adaptive hybrid transform processing only to specific audio blocks that require it, rather than uniformly processing all blocks. The system identifies blocks needing adaptive hybrid transform based on their specific characteristics examined in the first pass, and applies the appropriate transformation (adaptive hybrid transform or standard inverse transform) to each block individually. This localized approach recovers spectral information where needed while minimizing unnecessary computational steps for blocks that don't require adaptive processing.
Data Source
AI summary
The processing efficiency of a process used to decode frames of an enhanced AC-3 bit stream is improved by processing each audio block in a frame only once. Audio blocks of encoded data are decoded in block order rather than in channel order. Exemplary decoding processes for enhanced bit stream coding features such as adaptive hybrid transform processing and spectral extension are disclosed.