Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Scalable speech and audio encoding using combinatorial encoding of MDCT spectrum

A coding and spectrum technology, applied in the field of encoders and decoders, which can solve problems such as difficulty in implementation

Inactive Publication Date: 2010-09-15
QUALCOMM INC
View PDF0 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This is actually clearly impossible for two reasons: it is very difficult to implement, and the "best sound" selection criterion implies that human listeners

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
  • Scalable speech and audio encoding using combinatorial encoding of MDCT spectrum
  • Scalable speech and audio encoding using combinatorial encoding of MDCT spectrum
  • Scalable speech and audio encoding using combinatorial encoding of MDCT spectrum

Examples

Experimental program
Comparison scheme
Effect test

example

[0054] Figure 4 is a block diagram of a scalable encoder 402 according to one example. In a pre-processing stage prior to encoding, the input signal 404 is high-pass filtered 406 to suppress unwanted low-frequency components to produce a filtered input signal S HP (n). For example, high pass filter 406 may have a 25 Hz cutoff for wideband input signals and 100 Hz for narrowband input signals. The filtered input signal S is then resampled by the resampling module 408 HP (n) Resampling is performed to produce a resampled input signal S 12.8 (n). For example, the original input signal 404 may be sampled at 16 kHz and resampled to 12.8 kHz, which may be an internal frequency for layer L1 and / or L2 encoding. The pre-emphasis module 410 then applies a first-order high-pass filter to emphasize the resampled input signal S 12.8 (n) higher frequencies (and attenuate lower frequencies). The resulting signal is then passed to an encoder / decoder module 412, which may perform layer...

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 scalable speech and audio codec is provided that implements combinatorial spectrum encoding. A residual signal is obtained from a Code Excited Linear Prediction (CELP)-based encoding layer, where the residual signal is a difference between an original audio signal and a reconstructed version of the original audio signal. The residual signal is transformed at a Discrete Cosine Transform (DCT)-type transform layer to obtain a corresponding transform spectrum having a plurality of spectral lines. The transform spectrum spectral lines are transformed using a combinatorial position coding technique. The combinatorial position coding technique includes generating a lexicographical index for a selected subset of spectral lines, where each lexicographic index represents one of a plurality of possible binary strings representing the positions of the selected subset of spectral lines. The lexicographical index represents non-zero spectral lines in a binary string in fewer bits than the lengthof the binary string.

Description

[0001] Claim of priority under 35 U.S.C. §119 [0002] This patent application asserts that it was filed on October 22, 2007 and is entitled "Low-Complexity Technique for Encoding / Decoding of Quantized MDCT Spectrum in Scalable Speech+Audio Codecs), U.S. Provisional Application No. 60 / 981,814, which is assigned to the present assignee and is hereby expressly incorporated herein by reference . technical field [0003] The following description relates generally to encoders and decoders, and in particular to an efficient way of coding Modified Discrete Cosine Transform (MDCT) spectra as part of scalable speech and audio codecs. Background technique [0004] One goal of audio coding is to compress an audio signal to a desired limited amount of information, while maintaining as much as possible the original sound quality. During encoding, an audio signal in the time domain is transformed into the frequency domain. [0005] Perceptual audio coding techniques (eg, MPEG Layer 3...

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): G10L19/14G10L19/02
CPCG10L19/038G10L19/24G10L19/12
Inventor 尤里·列兹尼克黄鹏军
Owner QUALCOMM INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com