公开(公告)号：EP2538345A1

公开(公告)日：2012-12-26

申请号：EP11744578.3

申请日：2011-02-10

申请人： NEC Corporation ,  NTT DoCoMo, Inc.

发明人： HASHIMOTO, Takeshi

IPC分类号： G06F17/14

CPC分类号： G06F17/142

摘要： Disclosed is a fast Fourier transform circuit capable of high-speed reading and writing of data processed in the individual stages of a fast Fourier transform calculation without segmenting memory. The circuit is provided with: a calculation unit (1) which performs the fast Fourier calculations with digital Fourier transforms as structural elements; memory (2A, 2B) for storing the input/output data of the calculation unit (1); and a means (7) for controlling the writing of calculation results from the calculation unit (1) to the memory (2A, 2B) such that the order of reading data from the memory (2A, 2B) is the same at each stage in the multi-stage calculation performed on the data being processed by the calculation unit (11).

摘要翻译： 公开了一种快速傅立叶变换电路，能够高速地读取和写入在快速傅里叶变换计算的各个阶段中处理的数据，而不需要分段存储器。 该电路设有：以数字傅里叶变换作为结构要素执行快速傅里叶计算的计算单元（1） 用于存储计算单元（1）的输入/输出数据的存储器（2A，2B）; 以及用于控制从计算单元（1）向存储器（2A，2B）写入计算结果的装置（7），使得从存储器（2A，2B）读取数据的顺序在每个阶段相同 对由计算单元（11）处理的数据进行多级计算。

公开(公告)号：EP2141879B1

公开(公告)日：2012-08-15

申请号：EP09007913.8

申请日：2009-06-16

申请人： Broadcom Corporation

发明人： Garrett, David

IPC分类号： H04L27/26 ,  G06F17/14

CPC分类号： H04L27/2682 ,  H04L27/265

公开(公告)号：EP2279562A4

公开(公告)日：2012-07-11

申请号：EP09759019

申请日：2009-05-22

申请人： MICROSOFT CORP

发明人： MEHROTRA SANJEEV

IPC分类号： G10L19/02 ,  G06F17/14

CPC分类号： G10L19/0212 ,  G06F17/147 ,  G10L19/0017 ,  G10L19/022

公开(公告)号：EP2383662A3

公开(公告)日：2012-05-02

申请号：EP11164432.4

申请日：2011-05-02

申请人： SRC, Inc.

发明人： Dobart, Kristen L. ,  Addario, Michael T.

IPC分类号： G06F17/14

CPC分类号： G06F17/142

摘要： An FFT algorithm that splits a large bit width waveform into two parts, making it possible to conduct the FFT with much lower logic resource consumption is disclosed. The waveform is split into its most significant bits and its least significant bits through division in the form of a bit shift. Each partial signal is then put through an FFT algorithm. The MSB FFT output is then right bit shifted. The two partial FFT's are summed to create a single output that is largely equivalent to an FFT of the original waveform. Rounding distortion is reduced by overlapping the MSB and LSB partial signals.

摘要翻译： 公开了一种将大比特宽度波形分成两部分的FFT算法，使得可以以低得多的逻辑资源消耗进行FFT。 波形通过以位移的形式划分为最高有效位和最低有效位。 然后将每个部分信号通过FFT算法。 然后MSB FFT输出右移位。 将两个部分FFT相加以创建大部分等效于原始波形的FFT的单个输出。 通过重叠MSB和LSB部分信号来减少舍入失真。

公开(公告)号：EP2438535A2

公开(公告)日：2012-04-11

申请号：EP10728957.1

申请日：2010-06-04

申请人： QUALCOMM Incorporated

发明人： REZNIK, Yuriy

IPC分类号： G06F17/14

CPC分类号： H04N19/625 ,  G06F17/147 ,  H04N19/124 ,  H04N19/42 ,  H04N19/45 ,  H04N19/51 ,  H04N19/61 ,  H04N19/91

摘要： In general, techniques are described that provide for 4x4 transforms for media coding. A number of different 4x4 transforms are described that adhere to these techniques. As one example, an apparatus includes a 4x4 discrete cosine transform (DCT) hardware unit. The DCT hardware unit implements an orthogonal 4x4 DCT having an odd portion that applies first and second internal factors (C, S) that are related to a scaled factor (?) such that the scaled factor equals a square root of a sum of a square of the first internal factor (C) plus a square of the second internal factor (S). The 4x4 DCT hardware unit applies the 4x4 DCT implementation to media data to transform the media data from a spatial domain to a frequency domain. As another example, an apparatus implements a non-orthogonal 4x4 DCT to improve coding gain.

公开(公告)号：EP1982324A4

公开(公告)日：2012-01-25

申请号：EP07709334

申请日：2007-02-09

申请人： ERICSSON TELEFON AB L M

发明人： SEHLSTEDT MARTIN

IPC分类号： G10L11/02 ,  G06F17/14 ,  G10L19/00 ,  G10L21/02

CPC分类号： G10L19/012 ,  G10L19/0204 ,  G10L21/0208 ,  G10L21/0232 ,  G10L25/78

摘要： Embodiments of the present invention relate to a voice detector receiving an input signal that is divided into sub-signals that represent a frequency sub-band. The voice detector calculates, for each sub-band, a signal-to-noise (SNR) value based on a corresponding sub-signal for each sub-band and a background signal for each sub-band. The voice detector also calculates a power SNR value for each sub-band, where at least one of the power SNR values is calculated based on a non-linear function. The voice detector forms a single value based on the calculated power SNR values and compares the single value and a given threshold value to make a voice activity decision presented on an output port.

公开(公告)号：EP1672929A3

公开(公告)日：2012-01-25

申请号：EP05025155.2

申请日：2005-11-17

申请人： Microsoft Corporation

发明人： Tu, Chengjie ,  Malvar, Henrique, Sarmento ,  Srinivasan, Sridhar

IPC分类号： H04N7/26 ,  H04N7/30 ,  H04N7/50 ,  G06F17/14 ,  G10L19/14 ,  G10L19/00 ,  G10L19/02

CPC分类号： G10L19/0017 ,  G06F17/147 ,  G10L19/0212 ,  H04N19/119 ,  H04N19/122 ,  H04N19/60 ,  H04N19/61 ,  H04N19/63 ,  H04N19/80 ,  H04N19/86

摘要： An efficient lapped transform is realized using pre- and post-filters (or reversible overlap operators) that are structured of unit determinant component matrices. The pre-and post-filters are realized as a succession of planar rotational transforms and unit determinant planar scaling transforms. The planar scaling transforms can be implemented using planar shears or lifting steps. Further, the planar rotations and planar shears have an implementation as reversible/lossless operations, giving as a result, a reversible overlap operator.

公开(公告)号：EP1709627B1

公开(公告)日：2011-11-02

申请号：EP05711553.7

申请日：2005-01-14

申请人： DOLBY LABORATORIES LICENSING CORPORATION

发明人： CHENG, Corey, I. Dolby Laboratories Licensing ,  SMITHERS, Michael, J. Dolby Laboratories ,  LATHROP, David, N. Gallagher & Lathrop Suite 1111

IPC分类号： G10L19/02 ,  G06F17/14

CPC分类号： G06F17/147 ,  G10L19/0212

摘要： Estimates of spectral magnitude and phase are obtained by an estimation process using spectral information from analysis filter banks such as the Modified Discrete Cosine Transform. The estimation process may be implemented by convolution-like operations with impulse responses. Portions of the impulse responses may be selected for use in the convolution-like operations to trade off between computational complexity and estimation accuracy. Mathematical derivations of analytical expressions for filter structures and impulse responses are disclosed.

公开(公告)号：EP1620963A4

公开(公告)日：2011-09-21

申请号：EP04760677

申请日：2004-04-30

申请人： THOMSON LICENSING

发明人： MCNEELY DAVID LOWELL

IPC分类号： H04J11/00 ,  G06F17/14 ,  H04B7/185 ,  H04L5/06

CPC分类号： G06F17/147 ,  H04B7/18515 ,  H04L5/06

公开(公告)号：EP2361411A2

公开(公告)日：2011-08-31

申请号：EP09768115.9

申请日：2009-11-25

申请人： A Volute

发明人： PHAM, Tuyen ,  GREFF, Raphaël ,  ALLAIS, Paul

IPC分类号： G06F17/15 ,  H04S1/00 ,  H04S3/00 ,  G06F17/14

CPC分类号： G06F17/156 ,  G06F17/142 ,  H04S1/002 ,  H04S7/307 ,  H04S2400/11 ,  H04S2420/01 ,  H04S2420/07

摘要： The invention relates to a method for processing a signal, in particular a digital audio signal, suitable for being implemented by a digital signal processor (DSP) having libraries for calculating Fourier transforms from the complex number space to the complex number space, for digitally processing P input signals, P being an integer at least equal to 2, more particularly for filtering said P input signals by the convolution of sampled fast Fourier transforms (FFT), thus obtaining Q output signals, Q being an integer at least equal to 2. According to the invention, the method includes at least the following steps: - grouping said P input signals by twos, one representing the real portion and the other the imaginary portion of a complex number, thus defining one or more input vectors, - filtering said input vector or vectors, passing through the Fourier space, thus generating one or more output vectors, which are complex numbers, the real portion and the imaginary portion of said vector or each one of said output vectors respectively representing one of said Q output signals.