公开(公告)号：US20130051571A1

公开(公告)日：2013-02-28

申请号：US13604336

申请日：2012-09-05

Applicant: Frederik Nagel ,  Sascha Disch ,  Stephan Wilde ,  Lars Villemoes ,  Per Ekstrand

Inventor： Frederik Nagel ,  Sascha Disch ,  Stephan Wilde ,  Lars Villemoes ,  Per Ekstrand

IPC: H04R29/00

CPC classification number: G10L19/008 ,  G10L19/0204 ,  G10L21/038 ,  G10L21/04

Abstract: Apparatus for processing an audio signal to generate a bandwidth extended signal having a high frequency part and a low frequency part using parametric data for the high frequency part, the parametric data relating to frequency bands of the high frequency part includes a patch border calculator for calculating a patch border such that the patch border coincides with a frequency band border of the frequency bands. The apparatus further includes a patcher for generating a patched signal using the audio signal and the patch border.

Abstract translation: 用于处理音频信号以使用高频部分的参数数据产生具有高频部分和低频部分的带宽扩展信号的装置，与高频部分的频带有关的参数数据包括用于计算的频块边界计算器 贴片边界使得贴片边界与频带的频带边界重合。 该装置还包括一个修补器，用于使用音频信号和补片边界产生修补信号。

公开(公告)号：US08180819B2

公开(公告)日：2012-05-15

申请号：US12716760

申请日：2010-03-03

Applicant: Per Ekstrand ,  Lars Villemoes ,  Heiko Purnhagen

Inventor： Per Ekstrand ,  Lars Villemoes ,  Heiko Purnhagen

IPC: G06F17/10

CPC classification number: G10L19/0208

Abstract: An apparatus for processing a plurality of real-valued subband signals using a first real-valued subband signal and a second real-valued subband signal to provide at least a complex-valued subband signal comprises a multiband filter for providing an intermediate real-valued subband signal and a calculator for providing the complex-valued subband signal by combining a real-valued subband signal from the plurality of real-valued subband signals and the intermediate subband signal.

公开(公告)号：USRE43189E1

公开(公告)日：2012-02-14

申请号：US11371309

申请日：2000-01-26

Applicant: Lars G. Liljeryd ,  Kristofer Kjoerling ,  Per Ekstrand ,  Frederik Henn

Inventor： Lars G. Liljeryd ,  Kristofer Kjoerling ,  Per Ekstrand ,  Frederik Henn

IPC: G10L19/00 ,  G10L19/14

CPC classification number: G10L19/028 ,  G10L19/035 ,  G10L19/06 ,  G10L19/26 ,  G10L19/265 ,  G10L21/038 ,  G10L25/18

Abstract: Methods and an apparatus for enhancement of source coding systems utilizing high frequency reconstruction (HFR) are introduced. The problem of insufficient noise contents is addressed in a reconstructed highband, by using Adaptive Noise-floor Addition. New methods are also introduced for enhanced performance by means of limiting unwanted noise, interpolation and smoothing of envelope adjustment amplification factors. The methods and apparatus used are applicable to both speech coding and natural audio coding systems.

Abstract translation: 引入了利用高频重建（HFR）来增强源编码系统的方法和装置。 通过使用自适应噪声层加法，在重构的高频带中解决噪声含量不足的问题。 还引入了新的方法，通过限制不需要的噪声，包络调整放大因子的内插和平滑来增强性能。 所使用的方法和装置适用于语音编码和自然音频编码系统。

公开(公告)号：US20110004479A1

公开(公告)日：2011-01-06

申请号：US12881821

申请日：2010-09-14

Applicant: Per Ekstrand ,  Lars Villemoes

Inventor： Per Ekstrand ,  Lars Villemoes

IPC: G10L19/00

CPC classification number: G10L19/022 ,  G10L19/0212 ,  G10L19/24 ,  G10L21/038 ,  G10L21/04

Abstract: The present invention relates to transposing signals in time and/or frequency and in particular to coding of audio signals. More particular, the present invention relates to high frequency reconstruction (HFR) methods including a frequency domain harmonic transposer. A method and system for generating a transposed output signal from an input signal using a transposition factor T is described. The system comprises an analysis window of length La, extracting a frame of the input to signal, and an analysis transformation unit of order M transforming the samples into M complex coefficients. M is a function of the transposition factor T. The system further comprises a nonlinear processing unit altering the phase of the complex coefficients by using the transposition factor T, a synthesis transformation unit of order M transforming the altered coefficients into M altered samples, and a synthesis window of length Ls, generating a frame of the output signal.

Abstract translation: 本发明涉及在时间和/或频率上转置信号，特别涉及音频信号的编码。 更具体地，本发明涉及包括频域谐波转移器的高频重构（HFR）方法。 描述了使用转置因子T从输入信号生成转置输出信号的方法和系统。 该系统包括长度为La的分析窗口，提取输入信号的帧，以及将样本变换为M个复系数的阶数M的分析变换单元。 M是转置因子T的函数。该系统还包括通过使用转置因子T来改变复系数的相位的非线性处理单元，将改变的系数转换为M个改变的样本的阶数M的合成变换单元，以及 合成窗口长度Ls，产生输出信号的帧。

公开(公告)号：US20100179814A1

公开(公告)日：2010-07-15

申请号：US12687801

申请日：2010-01-14

Applicant: Per Ekstrand ,  Lars Villemoes ,  Heiko Purnhagen

Inventor： Per Ekstrand ,  Lars Villemoes ,  Heiko Purnhagen

IPC: G10L19/00

CPC classification number: G10L19/008 ,  G10L19/0208

Abstract: An apparatus for processing a plurality of real-valued subband signals using a first real-valued subband signal and a second real-valued subband signal to provide at least a complex-valued subband signal comprises a multiband filter for providing an intermediate real-valued subband signal and a calculator for providing the complex-valued subband signal by combining a real-valued subband signal from the plurality of real-valued subband signals and the intermediate subband signal.

Abstract translation: 一种用于使用第一实值子带信号和第二实值子带信号来处理多个实值子带信号以提供至少复值子带信号的装置包括多频带滤波器，用于提供中间实值子带 信号和用于通过组合来自多个实值子带信号和中间子带信号的实值子带信号来提供复值子带信号的计算器。

公开(公告)号：US20090132261A1

公开(公告)日：2009-05-21

申请号：US12273782

申请日：2008-11-19

Applicant: Kristofer Kjorling ,  Per Ekstrand ,  Holger Horich

Inventor： Kristofer Kjorling ,  Per Ekstrand ,  Holger Horich

IPC: G10L19/00

CPC classification number: G10L19/0208 ,  G10L19/0017 ,  G10L19/0204 ,  G10L19/028 ,  G10L19/06 ,  G10L19/07 ,  G10L19/093 ,  G10L19/167 ,  G10L19/24 ,  G10L19/26 ,  G10L19/265 ,  G10L21/038

Abstract: The present invention proposes a new method and a new apparatus for enhancement of audio source coding systems utilising high frequency reconstruction (HFR). It utilises a detection mechanism on the encoder side to assess what parts of the spectrum will not be correctly reproduced by the HFR method in the decoder. Information on this is efficiently coded and sent to the decoder, where it is combined with the output of the HFR unit.

Abstract translation: 本发明提出了一种利用高频重构（HFR）来增强音频源编码系统的新方法和新装置。 它利用编码器侧的检测机制来评估解码器中HFR方法将不能正确地再现频谱的哪些部分。 关于此的信息被有效地编码并发送到解码器，其中它与HFR单元的输出组合。

公开(公告)号：US07433817B2

公开(公告)日：2008-10-07

申请号：US11247176

申请日：2005-10-12

Applicant: Kristofer Kjörling ,  Per Ekstrand ,  Fredrik Henn ,  Lars Villemoes

Inventor： Kristofer Kjörling ,  Per Ekstrand ,  Fredrik Henn ,  Lars Villemoes

IPC: G01L19/02

CPC classification number: G10L21/038

Abstract: The present invention proposes a new method and a new apparatus for enhancement of audio source coding systems utilising high frequency reconstruction (HFR). It utilises adaptive filtering to reduce artifacts due to different tonal characteristics in different frequency ranges of an audio signal upon which HFR is performed. The present invention is applicable to both speech coding and natural audio coding systems.

Abstract translation: 本发明提出了一种利用高频重构（HFR）来增强音频源编码系统的新方法和新装置。 它利用自适应滤波来减少因执行HFR的音频信号的不同频率范围内的不同音调特性引起的伪影。 本发明适用于语音编码和自然音频编码系统。

公开(公告)号：US07242710B2

公开(公告)日：2007-07-10

申请号：US10112869

申请日：2002-04-02

Applicant: Per Ekstrand

Inventor： Per Ekstrand

IPC: H03H7/30

CPC classification number: H03H17/0266

Abstract: The present invention proposes a new method and apparatus for the improvement of digital filterbanks, by a complex extension of cosine modulated digital filterbanks. The invention employs complex-exponential modulation of a low-pass prototype filter and a new method for optimizing the characteristics of this filter. The invention substantially reduces artifacts due to aliasing emerging from independent modifications of subband signals, for example when using a filterbank as an spectral equalizer. The invention is preferably implemented in software, running on a standard PC or a digital signal processor (DSP), but can also be hardcoded on a custom chip. The invention offers essential improvements for various types of digital equalizers, adaptive filters, multiband companders and spectral envelope adjusting filterbanks used in high frequency reconstruction (HFR) systems.

Abstract translation: 本发明提出了一种通过余弦调制数字滤波器组的复数扩展来改进数字滤波器组的新方法和装置。 本发明采用低通原型滤波器的复指数调制和用于优化该滤波器的特性的新方法。 本发明基本上减少了由于子带信号的独立修改引起的混叠所产生的伪像，例如当使用滤波器组作为频谱均衡器时。 本发明优选地以在标准PC或数字信号处理器（DSP）上运行的软件实现，但也可以在定制芯片上被硬编码。 本发明为用于高频重建（HFR）系统的各种类型的数字均衡器，自适应滤波器，多频带压缩器和频谱包络调整滤波器组提供了重要的改进。

公开(公告)号：US20070100612A1

公开(公告)日：2007-05-03

申请号：US11463263

申请日：2006-08-08

Applicant: Per Ekstrand ,  Lars Villemoes ,  Heiko Purnhagen

Inventor： Per Ekstrand ,  Lars Villemoes ,  Heiko Purnhagen

IPC: G10L19/00

CPC classification number: G10L19/0208

Abstract: An apparatus for processing a plurality of real-valued subband signals using a first real-valued subband signal and a second real-valued subband signal to provide at least a complex-valued subband signal comprises a multiband filter for providing an intermediate real-valued subband signal and a calculator for providing the complex-valued subband signal by combining a real-valued subband signal from the plurality of real-valued subband signals and the intermediate subband signal.

Abstract translation: 一种用于使用第一实值子带信号和第二实值子带信号来处理多个实值子带信号以提供至少复值子带信号的装置包括多频带滤波器，用于提供中间实值子带 信号和用于通过组合来自多个实值子带信号和中间子带信号的实值子带信号来提供复值子带信号的计算器。

公开(公告)号：US07191121B2

公开(公告)日：2007-03-13

申请号：US11246284

申请日：2005-10-11

Applicant: Lars Gustaf Liljeryd ,  Kristofer Kjörling ,  Per Ekstrand ,  Fredrik Henn

Inventor： Lars Gustaf Liljeryd ,  Kristofer Kjörling ,  Per Ekstrand ,  Fredrik Henn

IPC: G10L21/00

CPC classification number: G10L19/06 ,  G10L19/0208 ,  G10L19/022 ,  G10L19/035 ,  G10L21/038 ,  G10L25/18

Abstract: The present invention provides a new method and an apparatus for spectral envelope encoding. The invention teaches how to perform and signal compactly a time/frequency mapping of the envelope representation, and further, encode the spectral envelope data efficiently using adaptive time/frequency directional coding. The method is applicable to both natural audio coding and speech coding systems and is especially suited for coders using SBR [WO 98/57436] or other high frequency reconstruction methods.