Pitch Extraction Device Using Bitstream Re-encoding

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In search methods for sound signals based on pitch, decoding and recalculating large amounts of encoded data lead to increased operation time and power consumption, especially when dealing with numerous pieces of encoded data.

Innovation Solution

A pitch extraction device that re-encodes bit streams of encoded data into a second bit stream by allocating values based on pulse positions, allowing for the calculation of a sound signal's fundamental frequency through autocorrelation, reducing the need for full decoding and subsequent processing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If encoded data is decoded and pitch is recalculated, then pitch extraction accuracy is improved, but operation time and power consumption increase

Engineering Contradiction:

Improvepitch extraction accuracyVSAvoidoperation time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent extracts only the essential information needed for pitch calculation from the encoded bitstream by identifying patterns of consecutive identical bits, rather than fully decoding the entire encoded data. This selective extraction maintains pitch extraction accuracy while significantly reducing operation time and computational resources required.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent performs preliminary scanning of the bitstream to identify patterns of consecutive identical bits before conducting full pitch calculation. By pre-identifying these patterns, the system prepares the data in a form that enables faster pitch extraction without requiring complete decoding of the encoded signal.

Inventive Principle:

Principle #10Preliminary action

2Measurement precision

If encoded data is decoded and pitch is recalculated, then pitch extraction accuracy is improved, but power consumption increases

Engineering Contradiction:

Improvepitch extraction accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent performs partial decoding by only processing portions of the bitstream that contain pitch information, specifically identifying patterns of consecutive identical bits. This partial action approach achieves sufficient pitch extraction accuracy without the excessive power consumption associated with complete decoding of all encoded data.

Inventive Principle:

Principle #16Partial or excessive action

3Adaptability or versatility

If large amounts of encoded data are processed, then comprehensive pitch search capability is improved, but operation time increases

Engineering Contradiction:

Improvepitch search capabilityVSAvoidoperation time

Core Design Contradiction:

Adaptability or versatilityVSLoss of time

Solution Approach 1:

The patent segments the bitstream into manageable sections by identifying patterns of consecutive identical bits, allowing for efficient processing of large amounts of encoded data. This segmentation enables the system to handle comprehensive pitch search capabilities across multiple encoded signals while reducing overall operation time through parallel or sequential processing of smaller segments.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent replaces the mechanical process of full decoding with a computational pattern recognition approach that identifies pitch information directly from the encoded bitstream. This substitution of the processing mechanism maintains comprehensive pitch search capability while dramatically reducing operation time by avoiding unnecessary decoding operations.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach significantly reduces operation time and power consumption while maintaining accurate pitch calculation, enabling efficient extraction of pitch values from encoded sound signals.

Implementation Method 1

calculating an estimation value of a fundamental frequency of the sound signal in accordance with an autocorrelation of the second bit stream

Methodology Applied

Scientific EffectAutocorrelation:

Data Source

PatentUS10515656B2Pitch extraction device and pitch extraction method by encoding a bitstream organized into equal sections according to bit values

Publication Date: 2019.12.24 FUJITSU LTD

AI summary

A pitch extraction device includes a processor configured to perform a process including: dividing a first bit stream in encoded data into a plurality of sections each having a prescribed section length, the encoded data being obtained by performing entropy encoding on a residual signal calculated by performing linear prediction analysis on a sound signal; allocating a first value or a second value to each of the plurality of sections in the first bit stream in accordance with a bit value in each of the plurality of sections; generating a second bit stream obtained by re-encoding the first bit stream according to the first value and the second value that have been allocated to each of the plurality of sections in the first bit stream; and calculating a fundamental frequency of the sound signal in accordance with an autocorrelation of the second bit stream.