Speech coding apparatus, speech decoding apparatus, speech coding method, and speech decoding method

A sound coding and coding technology, which is applied in speech analysis, instruments, etc., can solve the problems of band-dependent sound signal quality reduction, without considering residual signal strength, etc., and achieve the effect of improving quality

Inactive Publication Date: 2008-02-13
CASIO COMPUTER CO LTD
View PDF0 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0013] Therefore, in the processing of the residual signal for different bands, the band dependence of the strength of the residual signal is not taken into account, which will cause the quality degradation of the audio signal decoded by the decoding device.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Speech coding apparatus, speech decoding apparatus, speech coding method, and speech decoding method
  • Speech coding apparatus, speech decoding apparatus, speech coding method, and speech decoding method
  • Speech coding apparatus, speech decoding apparatus, speech coding method, and speech decoding method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0060] Hereinafter, an audio coding device and an audio decoding device according to embodiments of the present invention will be described in detail.

[0061] FIG. 1 is a functional configuration diagram of an audio coding device 111 according to the present embodiment.

[0062] The voice encoding device 111, as shown in FIG. 125. The sending unit 127.

[0063] The predictive analysis unit 131 incorporates a predictive analysis inverse filter calculator 141 .

[0064] The band filter unit 133 has: a first band filter 151, a second band filter 153, a third band filter 155, and necessary band filters after the third band filter 155 (Fig. not shown).

[0065] The gain calculator 135 includes a first gain calculator 161 , a second gain calculator 163 , and necessary gain calculators (not shown) after the second gain calculator 163 .

[0066] Voiceless and unvoiced discrimination and tone extractor 137 have: first voiced and unvoiced discrimination and tone extractor 171, seco...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

In a speech coding apparatus, a band-pass filter unit separates a residual signal generated by a predictive analyzer into band by band components. Then, a gain calculation unit and a voiced / unvoiced discrimination and pitch extraction unit acquire information on an intensity characterizing each band, information on a result of discrimination as to whether each band-by-band component is a voiced sound or unvoiced sound, and information on a pitch frequency when it is a voiced sound. The acquired information is coded together with a predictive coefficient and is transmitted to a speech decoding apparatus. The speech decoding apparatus generates an excitation signal while reflecting the feature of each band of the original residual signal. This makes the excitation signal an efficient replica of the original residual signal.

Description

technical field [0001] The present invention relates to an audio encoding device, an audio decoding device, an audio encoding method, an audio decoding method, and a computer-readable recording medium for performing analysis-synthesis-type audio encoding and audio decoding. Background technique [0002] For the audio compression technology used in mobile phones and the like, technological developments are progressing to satisfy the restrictive conditions of, for example, a sampling frequency of 8 kHz and a transmission and reception speed of 4 kbps. This audio compression technique is also classified as a low-bit-rate audio compression technique among analysis-synthesis-type audio compression techniques. [0003] As a typical analysis-synthesis type low-bit-rate audio compression technology, for example, there is an 8 kbps audio coding method disclosed in ITU-T Recommendation G.729. In this audio encoding method, an encoding device generates a prediction coefficient and a r...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G10L19/08G10L11/02G10L19/083G10L19/02G10L19/06G10L19/087G10L25/90G10L25/93
CPCG10L19/087
Inventor 井手博康
Owner CASIO COMPUTER CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap