公开(公告)号：US10115410B2

公开(公告)日：2018-10-30

申请号：US15317794

申请日：2014-06-10

Applicant: Peter Graham Craven ,  REINET S.A.R.L

Inventor： Peter Graham Craven ,  John Robert Stuart

IPC: G10L19/26 ,  G10L19/02 ,  G10L19/022 ,  G10L19/03

Abstract: Encoding and decoding systems are described for the provision of high quality digital representations of audio signals with particular attention to the correct perceptual rendering of fast transients at modest sample rates. This is achieved by optimizing downsampling and upsampling filters to minimize the length of the impulse response while adequately attenuating alias products that have been found perceptually harmful.

公开(公告)号：US08533571B2

公开(公告)日：2013-09-10

申请号：US13122202

申请日：2009-09-11

Applicant: Peter Graham Craven ,  Malcolm Law

Inventor： Peter Graham Craven ,  Malcolm Law

IPC: G11C29/00

CPC classification number: H03M7/40 ,  H04N19/184 ,  H04N19/187 ,  H04N19/89 ,  H04N19/91 ,  H04N19/93

Abstract: A method is described for packing variable-length entropy coded data into a fixed rate data stream along with resolution enhancement data, the method providing tightly constrained propagation of transmission channel errors and graceful degradation of signal resolution as entropy-coded data rate increases. An application to a multiband ADPCM audio codec is also described.

Abstract translation: 描述了一种用于将可变长度熵编码数据与分辨率增强数据一起打包成固定速率数据流的方法，该方法提供传输信道错误的严格约束的传播和信号分辨率的平滑劣化，因为熵编码的数据速率增加。 还描述了对多频带ADPCM音频编解码器的应用。

公开(公告)号：US06774820B2

公开(公告)日：2004-08-10

申请号：US10643073

申请日：2003-08-18

Applicant: Peter Graham Craven ,  Malcolm James Law ,  John Robert Stuart

Inventor： Peter Graham Craven ,  Malcolm James Law ,  John Robert Stuart

IPC: H03M700

CPC classification number: H04H20/88 ,  G11B20/00007 ,  G11B20/00992 ,  G11B20/10527 ,  G11B2020/00014 ,  G11B2020/10546 ,  G11B2220/2562 ,  H03M7/30 ,  H04N5/76 ,  H04S3/02 ,  H04S2420/03

Abstract: A lossless encoder and decoder are provided for transmitting a multichannel signal on a medium such as DVD-Audio. The encoder accepts additionally a downmix specification and splits the encoded stream into two substreams, such that a two-channel decoder of meagre computational power can implement the downmix specification by decoding one substream, while a multichannel decoder can decode the original multichannel signal losslessly using both substreams. Further features provide for efficient implementation on 24-bit processors, for confirmation of lossless reproduction to the user, and for benign behaviour in the case of downmix specifications that result in overload. The principle is also extended to mixed-rate signals, where for example some input channels are sampled at 48 kHz and some are sampled at 96 kHz.

Abstract translation: 提供了一种无损编码器和解码器，用于在诸如DVD-Audio的介质上发送多声道信号。 编码器另外接收一个下混指定，并将编码流分解成两个子流，使得计算能力较弱的双通道解码器可以通过解码一个子流来实现下混规范，而多通道解码器可以无损地使用两个子码解码原始多通道信号 子流 其他功能提供了24位处理器上的高效实现，用于确认用户的无损复制，以及在导致过载的降混规范的情况下的良性行为。 该原理还扩展到混合速率信号，其中例如一些输入通道以48kHz采样，一些输入通道以96kHz采样。

公开(公告)号：US5784017A

公开(公告)日：1998-07-21

申请号：US670696

申请日：1996-06-26

Applicant: Peter Graham Craven

Inventor： Peter Graham Craven

IPC: H03M1/08 ,  H03M1/10 ,  H03M1/20 ,  H03M1/50 ,  H03M1/82 ,  H03M3/02 ,  H03M3/04 ,  H03M1/00

CPC classification number: H03M1/1038 ,  H03M1/208 ,  H03M3/506 ,  H03M1/504 ,  H03M1/822

Abstract: A signal convertor comprising a pulse modulator, and a modifier for modifying the signal input thereto in dependence upon the error in previous values of the output thereof, to reduce the effects of said error within a desired signal band.

Abstract translation: 一种信号转换器，包括脉冲调制器和用于根据其输出的先前值的误差修改输入到其中的信号的修正器，以减少所需信号频带内的所述误差的影响。

公开(公告)号：US20170116996A1

公开(公告)日：2017-04-27

申请号：US15300598

申请日：2015-03-26

Applicant: Peter Graham Craven ,  Malcolm Law

Inventor： Peter Graham Craven ,  Malcolm Law

IPC: G10L19/018 ,  G10L19/032 ,  G10L19/10 ,  G10L19/00

CPC classification number: G10L19/018 ,  G10L19/0017 ,  G10L19/032 ,  G10L19/10

Abstract: An encoding method and encoder is provided for transparent lossless audio watermarking by quantising an original PCM audio signal twice, each quantisation quantising to a quantisation grid. As a PCM signal is inherently already quantised, there are three quantisation grids to consider, the first being the quantisation grid of the original PCM signal, the second being that of the watermarked signal and the third being that of an intermediate signal. The technique reduces the amount of introduced quantisation error, spectrally shapes the error and fully decorrelates signal alterations from the original audio, thus making the error more similar to additive noise. A decoding method and decoder is also provided, as is a method of altering the watermark without fully decoding the encoded signal.

公开(公告)号：US20150279378A1

公开(公告)日：2015-10-01

申请号：US14353660

申请日：2012-10-24

Applicant: Peter Graham CRAVEN ,  Malcolm LAW

Inventor： Peter Graham Craven ,  Malcolm Law

IPC: G10L19/00

CPC classification number: G10L19/0017 ,  G10L19/018 ,  G11B20/00289 ,  G11B20/00891 ,  G11B20/10527 ,  G11B2020/10546

Abstract: Methods are disclosed for an encoder to embed a data stream into a quantised PCM digital audio signal and for a corresponding decoder to both retrieve the data stream and losslessly reconstruct the exact original audio. Some methods employ complimentary amplification and attenuation, while others employ gain redistribution. Pre-emphasis and soft clipping techniques are described as methods of losslessly reducing the peak excursion of the PCM audio signal. Also described is the lossless placing of data at predetermined positions within an audio stream.

Abstract translation: 公开了一种用于编码器将数据流嵌入到量化PCM数字音频信号中的方法，并且针对相应的解码器来检索数据流并且无损地重建精确的原始音频。 一些方法采用补偿放大和衰减，而其他方法则采用增益再分配。 预加重和软削波技术被描述为无损地减少PCM音频信号的峰值偏移的方法。 还描述了在音频流内的预定位置处的数据的无损放置。

公开(公告)号：US20110179338A1

公开(公告)日：2011-07-21

申请号：US13122202

申请日：2009-09-11

Applicant: Peter Graham Craven ,  Malcolm Law

Inventor： Peter Graham Craven ,  Malcolm Law

IPC: G06F11/10

CPC classification number: H03M7/40 ,  H04N19/184 ,  H04N19/187 ,  H04N19/89 ,  H04N19/91 ,  H04N19/93

Abstract: A method is described for packing variable-length entropy coded data into a fixed rate data stream along with resolution enhancement data, the method providing tightly constrained propagation of transmission channel errors and graceful degradation of signal resolution as entropy-coded data rate increases. An application to a multiband ADPCM audio codec is also described.

Abstract translation: 描述了一种用于将可变长度熵编码数据与分辨率增强数据一起打包成固定速率数据流的方法，该方法提供传输信道错误的严格约束的传播和信号分辨率的平滑劣化，因为熵编码的数据速率增加。 还描述了对多频带ADPCM音频编解码器的应用。

公开(公告)号：US07193538B2

公开(公告)日：2007-03-20

申请号：US10913160

申请日：2004-08-05

Applicant: Peter Graham Craven ,  Malcolm James Law ,  John Robert Stuart

Inventor： Peter Graham Craven ,  Malcolm James Law ,  John Robert Stuart

IPC: H03M7/00

CPC classification number: H04H20/88 ,  G11B20/00007 ,  G11B20/00992 ,  G11B20/10527 ,  G11B2020/00014 ,  G11B2020/10546 ,  G11B2220/2562 ,  H03M7/30 ,  H04N5/76 ,  H04S3/02 ,  H04S2420/03

Abstract: A lossless encoder and decoder are provided for transmitting a multichannel signal on a medium such as DVD-Audio. The encoder accepts additionally a downmix specification and splits the encoded stream into two substreams, such that a two-channel decoder of meagre computational power can implement the downmix specification by decoding one substream, while a multichannel decoder can decode the original multichannel signal losslessly using both substreams. Further features provide for efficient implementation on 24-bit processors, for confirmation of lossless reproduction to the user, and for benign behaviour in the case of downmix specifications that result in overload. The principle is also extended to mixed-rate signals, where for example some input channels are sampled at 48 kHz and some are sampled at 96 kHz.

Abstract translation: 提供了一种无损编码器和解码器，用于在诸如DVD-Audio的介质上发送多声道信号。 编码器另外接收一个下混指定，并将编码流分解成两个子流，使得计算能力较弱的双通道解码器可以通过解码一个子流来实现下混规范，而多通道解码器可以无损地使用两个子码解码原始多通道信号 子流 其他功能提供了24位处理器上的高效实现，用于确认用户的无损复制，以及在导致过载的降混规范的情况下的良性行为。 该原理还扩展到混合速率信号，其中例如一些输入通道以48kHz采样，一些输入通道以96kHz采样。

公开(公告)号：US11996816B2

公开(公告)日：2024-05-28

申请号：US17006036

申请日：2020-08-28

Applicant: Peter Graham Craven ,  John Robert Stuart

Inventor： Peter Graham Craven ,  John Robert Stuart

IPC: H03H17/02 ,  G11B20/10 ,  H03H17/00 ,  H03H17/04 ,  H03H17/06

CPC classification number: H03H17/0261 ,  G11B20/10 ,  H03H17/04 ,  G10H2250/071 ,  G10H2250/121 ,  G11B2020/10546 ,  H03H2017/009 ,  H03H2017/0472 ,  H03H17/0664

Abstract: Methods and devices are described for reducing the audible effect of pre-responses in an audio signal. The pre-responses are effectively delayed by employing a digital non-minimum-phase filter, which includes a zero lying outside the unit circle in its z-transform response. This zero is not paired with another zero at a reciprocal position inside the unit circle, as this would linearise the phase modification. The filtering can introduce a greater group delay at the pre-response frequency than at a low frequency, such as 500 Hz or even 0 Hz. The technique can be used to reduce pre-responses in an existing audio signal and also to pre-empt pre-responses that would be introduced to the audio signal by subsequent processing.

公开(公告)号：US11388510B2

公开(公告)日：2022-07-12

申请号：US16305745

申请日：2017-06-02

Applicant: Peter Graham Craven ,  Christopher Julian Travis

Inventor： Peter Graham Craven ,  Christopher Julian Travis

IPC: H04R1/40 ,  H04R5/027 ,  H04S3/00

Abstract: A compact multi-element microphone has two rings of directional sensors. Using simple analog electronics, it delivers first-order outputs with low noise, wide bandwidth and tight transient response. The double-ring structure provides exceptionally high directional fidelity in the horizontal plane, while also keeping out-of-plane behaviour under control. This enables faithful capture of ambience, reflections and reverberation. A non-radial capsule arrangement moderates cavity resonances and reduces shading. Combined with digital electronics, the array can efficiently provide second-order and higher-order horizontal directivities that maintain their performance over a wider frequency range than with prior solutions. Outputs can be mono, two-channel stereo and multichannel surround sound. Applications include 360-degree immersive audio, with-height concert hall recording, and advanced voice capture using electronic steering of beams and nulls.