Band spreading coding method and device and decode method and device

A technology of frequency band extension and encoding method, applied in the fields of frequency band extension encoding method and device, decoding method and device, capable of solving problems such as low sound quality and large distortion

Active Publication Date: 2007-12-19
BEJING ANGEL VOICE DIGITAL TECH
View PDF0 Cites 55 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, the frequency band extension technology of AMR WB+ has considerable limitations, and the sound quality ge

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
  • Band spreading coding method and device and decode method and device
  • Band spreading coding method and device and decode method and device
  • Band spreading coding method and device and decode method and device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0120] Embodiment 1: a first type of frequency band extension coding device.

[0121] A schematic diagram of the structure of the frequency band extension encoding device of this embodiment is shown in FIG. 5 . The frequency band extension coding method of the present invention includes a time-varying prediction analysis module 501 , a signal type analysis module 502 , a spectrum parameter encoding module 503 , a time-varying prediction synthesis module 504 and a time-domain adaptive gain adjustment parameter extraction module 505 .

[0122] The time-varying prediction analysis module 501 is used to receive the original high-frequency time-domain signal output by the preprocessing and analysis filter bank 101, and divide the received original high-frequency time-domain signal according to the analysis result from the signal type analysis module 502 It is one or more predicted frames, and the predicted frame is a group of time-domain signal samples, which is the unit of linear ...

Embodiment 2

[0204] Embodiment 2: a second type of frequency band extension coding device.

[0205] The structural diagram of the frequency band extension coding device of this embodiment is shown in FIG. 11 . Compared with FIG. 5 , a coding mode selection module 507 is added, and other modules are identical to those with the same name in FIG. 5 . The encoding mode selection module 507 is used to receive the low-frequency encoding mode information and the low-frequency excitation signal or spectrum from the low-frequency encoder, and perform processing according to the preset high-frequency encoding mode, and the preset high-frequency encoding mode is divided into mode 1 and mode 2. Mode 1 performs both frequency domain adjustment and time domain adjustment on the TCX frame low-frequency excitation spectrum output by the low-frequency encoder or the low-frequency time-domain excitation signal of the ACELP frame; while mode 2 performs frequency domain adjustment on the TCX frame low-frequenc...

Embodiment 3

[0212] Embodiment 3: a first type of frequency band extension decoding device.

[0213] The device in this embodiment is a decoding device corresponding to the encoding device in Embodiment 2. Its structural diagram is shown in FIG. and time-varying prediction synthesis module 1204 .

[0214] The high-frequency decoding mode selection module 1201 first selects the high-frequency decoding mode. The high-frequency decoding mode corresponds to the high-frequency encoding mode in Embodiment 2, including mode 1 and mode 2. The selection method is the same as that of the encoding end. When mode 1 is selected, the low-frequency excitation spectrum of the TCX frame obtained from the TCX decoder is output to the spectral parameter decoding module 1202, or the low-frequency excitation signal of the ACELP frame obtained from the ACELP decoder is transformed by DFT to obtain the low-frequency excitation of the ACELP frame spectrum, and output the low-frequency excitation spectrum of the ...

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

A coding method of frequency hand expansion includes copying special frequency band of low frequency excited chart to special frequency hand of high frequency (HR) to obtain HR copied-excited chart, obtaining original HR excited chart according to certain signal, regulating HR copied-excited chart to obtain regulated HR copied-excite chart, making IDFT conversion on said chart to obtain HR copied-excited signal, filtering said signal to obtain rebuilt HR time domain signal, picking up gain regulation parameter of time domain and outputting HR parameter. The device used for realizing said method is also disclosed.

Description

technical field [0001] The invention relates to the fields of wideband sound encoding, decoding and sound synthesis, in particular to a frequency band extension encoding method and device, and a decoding method and device. Background technique [0002] After years of technological development, digital audio coding technology has become very mature. At present, many audio coding technologies have become industrial standards and are widely used and integrated into people's daily life. These technologies are AC-3 from Dolby Labs, Digital Theater Systems (DTS) from Digital Theater Systems, MP3 from the Moving Picture Experts Group (MPEG) and Advanced Audio Coding (Advanced Audio). Coding, AAC), Microsoft's Windows Media Audio (Windows Media Audio, WMA), Sony's ATRAC, ITU (International Telecommunication Union, ITU)'s G.723 and G.729, etc., are digital sound coding technologies in result of different stages of development. [0003] Due to the complexity of sound generation, sou...

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
IPC IPC(8): G10L19/04
Inventor 徐光锁
Owner BEJING ANGEL VOICE DIGITAL TECH
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