Device for perceptual weighting in audio encoding/decoding

A perception and equipment technology, applied in the field of perception weighting equipment, can solve the problem of complex calculation time of filters

Inactive Publication Date: 2009-03-11
FRANCE TELECOM SA
View PDF0 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0023] However, this technique proposed in the case of the G.729EV standard has the disadvantage of using a full-band perceptual weighting filter
The associated filter is relatively complex in terms of computation time
[0024] The technical problem to be solved by the subject matter of the invention is therefore to propose a perceptual weighting device for encoding / decoding an audio signal in a given frequency band, which provides a full-band perceptual weighting filtering, i.e. On, especially over the wideband of 0 to 8000Hz for hierarchical audio encoders, not doing this would result in long computations, which are costly in terms of resources

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
  • Device for perceptual weighting in audio encoding/decoding
  • Device for perceptual weighting in audio encoding/decoding
  • Device for perceptual weighting in audio encoding/decoding

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0069] Figure 2 shows a subband hierarchical audio encoder for bit rates from 8kbps to 32kbps. The figure shows various steps of a corresponding encoding method.

[0070] The input signal in the "broad" frequency band from 50 Hz to 7000 Hz and sampled at 16 kHz is first divided into two adjacent sub-bands by a quadrature mirror filter (QMF). The first sub-band is obtained by low-pass (L) filtering 300 and decimation 301, which is from 0 to 4000 Hz, also called the low frequency band, and the second sub-band is obtained by high-pass (H) filtering 302 and decimation 303, which is from 4000 Hz to 8000Hz, also known as the high frequency band. In a preferred embodiment, the L filter 300 and the H filter 302 have length 64 and are described in the following paper: J. Johnston, "A filter family designed for use in quadrature mirror filter banks", ICASSP, vol.5, pp. 291-294, 1980.

[0071] The first sub-band is pre-processed by a high-pass filter 304 that removes components below ...

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

The invention relates to a hierarchical audio encoder in a frequency band divided into a first sub-band and a second sub-band which are adjacent to each other, said encoder comprising: a core encoder (305) for encoding an original signal in the first sub-band of the frequency band; a calculation stage (306) for calculating a residual signal {e} from the original signal and from the signal supplied by the core encoder; and a device (307) for perceptual weighting of the residual signal {e}. According to the invention, the perceptual weighting device comprises a perceptual weighting filter (307) with gain compensation that can perform the spectral continuity between the signal at the output of the perceptual weighting filter with gain compensation and the signal in the second sub-band. The invention can be applied to the transmission and storage of digital signals, such as the audio-frequency signals of speech, music, etc.

Description

technical field [0001] The present invention relates to a perceptual weighting device for encoding / decoding audio signals in a given frequency band. It also relates to a hierarchical audio encoder and a hierarchical audio decoder comprising the encoding / decoding device of the invention. [0002] The invention has particularly advantageous application in the transmission and storage of digital signals such as audio speech, music, etc. signals. Background technique [0003] Various techniques exist for digitizing and compressing audio speech, music, etc. signals. The most common methods are: [0004] "Waveform coding" methods such as PCM and ADPCM coding; [0005] "parametric analysis / synthetic coding" methods, such as Codebook Excited Linear Prediction (CELP) coding; [0006] • "Subband or Transform Perceptual Coding" method. [0007] These conventional techniques for encoding audio-frequency signals are described in "Speech Coding and Synthesis", editors W.B. Kleijn and...

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): G10L19/02G10L19/24
CPCG10L19/24G10L19/0208G10L19/04G10L19/12
Inventor 斯蒂芬·拉戈特罗曼·特里林
Owner FRANCE TELECOM SA
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