Audio Vector Coding With Permutation Indexing for Lower Complexity

Solution Overview

Problem

The existing multi-rate lattice vector quantization approach in audio coding involves high calculation complexity due to the need for multiple irregular factorials, which complicates the coding and decoding processes.

Innovation Solution

A vector coding method that decomposes an initial vector into a sign vector and an absolute vector, performs multi-level permutation-based coding on the absolute vector, and combines the sign code and absolute vector code to obtain a final code, reducing calculation complexity by avoiding complex factorial calculations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If multi-rate lattice vector quantization is used for audio coding, then quantization accuracy is improved, but calculation complexity increases due to multiple irregular factorial computations

Engineering Contradiction:

Improvequantization accuracyVSAvoidcalculation complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the vector coding process into three independent stages: sign bit coding, magnitude coding, and permutation-based indexing. By dividing the complex quantization task into these manageable segments, each stage can be processed separately with simpler computations, eliminating the need for multiple irregular factorial calculations while maintaining quantization accuracy.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary classification by determining which codebook (Q0, Q2, Q3, or Q4) the input vector belongs to before actual coding. This preliminary action allows the system to pre-determine the coding structure and avoid complex real-time factorial computations during the actual encoding process, significantly reducing calculation complexity.

Inventive Principle:

Principle #10Preliminary action

2Measurement precision

If multiple irregular factorials are calculated during coding and decoding, then vector quantization precision is maintained, but the amount of computation and time required increases

Engineering Contradiction:

Improvevector quantization precisionVSAvoidcoding and decoding time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent segments the vector coding process into three independent stages: sign bit coding, magnitude coding, and permutation-based indexing. By dividing the complex quantization task into these manageable segments, each stage can be processed separately with simpler computations, eliminating the need for multiple irregular factorial calculations while maintaining quantization accuracy.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary classification by determining which codebook (Q0, Q2, Q3, or Q4) the input vector belongs to before actual coding. This preliminary action allows the system to pre-determine the coding structure and avoid complex real-time factorial computations during the actual encoding process, significantly reducing calculation complexity.

Inventive Principle:

Principle #10Preliminary action

3Measurement precision

If the coding process uses complex factorial calculations, then accurate vector representation is achieved, but ease of operation deteriorates

Engineering Contradiction:

Improvevector representation accuracyVSAvoidcoding process simplicity

Core Design Contradiction:

Measurement precisionVSEase of operation

Solution Approach 1:

The patent segments the vector coding process into three independent stages: sign bit coding, magnitude coding, and permutation-based indexing. By dividing the complex quantization task into these manageable segments, each stage can be processed separately with simpler computations, eliminating the need for multiple irregular factorial calculations while maintaining quantization accuracy.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent transforms the coding parameters by separating the vector into sign bits and magnitudes, then applying permutation-based indexing to the magnitudes. This parameter transformation converts complex factorial calculations into simpler lookup table operations, significantly improving ease of operation while preserving vector representation accuracy.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS7738558B2Vector coding method and apparatus and computer program

Publication Date: 2010.06.15 TOP QUALITY TELEPHONY LLC

AI summary

A vector coding apparatus and method includes decomposing an initial vector to obtain a sign vector and an initial absolute vector. Coding the sign vector to obtain a sign code, performing multi-level permutation-based coding on the initial absolute vector to obtain an absolute vector code, and combining the sign code and the absolute vector code. Optionally determining, before decomposing the initial vector, a characteristic codebook to which the initial vector belongs, obtaining a characteristic value of the characteristic codebook, and combining a code of the initial vector to obtain a final code of the initial vector. The performing step can include removing from the initial absolute vector any element having a value which satisfies a preset condition, constructing a new absolute vector with elements not satisfying the preset condition, and coding positions of the elements not satisfying the preset condition in the initial absolute vector to obtain a position code.