公开(公告)号：US07031916B2

公开(公告)日：2006-04-18

申请号：US09871779

申请日：2001-06-01

申请人： Dunling Li ,  Daniel C. Thomas ,  Gokhan Sisli

发明人： Dunling Li ,  Daniel C. Thomas ,  Gokhan Sisli

IPC分类号： G10L11/06

CPC分类号： G10L25/78 ,  G10L2021/02168 ,  G10L2025/783

摘要： A method of initializing an ITU Recommendation G.729 Annex B voice activity detection (VAD) device is disclosed, having the steps of (1) extracting a set of parameters from a signal that characterize the signal; (2) calculating an energy measure of the signal from the set of parameters; (3) comparing the energy measure with a reference value; (4) determining an initial value for an average of a noise characteristic of the signal; and (5) counting the number of times the energy measure equals or exceeds the reference level.Also disclosed is a method of converging an ITU Recommendation G.729 Annex B voice activity detection (VAD) device, having the steps of: (1) determining a noise identification threshold value; (2) comparing a number of energy measures of a signal to the noise threshold value; (3) determining a first value representing an average of the number of energy measures, when the energy measure is less than the noise threshold, wherein only the energy measures of the number of energy measures having values less than the noise threshold value are used to determine the first value; (4) determining a second value representing an average of the number of energy measures; and (5) substituting the first value for the second value when a specific event occurs, indicating the divergence of the two values.

公开(公告)号：US07386447B2

公开(公告)日：2008-06-10

申请号：US10287572

申请日：2002-11-04

申请人： Dunling Li ,  Gokhan Sisli ,  John T. Dowdal ,  Zoran Mladenovic

发明人： Dunling Li ,  Gokhan Sisli ,  John T. Dowdal ,  Zoran Mladenovic

IPC分类号： G10L21/00

CPC分类号： G10L19/07

摘要： An overflow problem of LSF quantization in G.729 Annex B speech encoding which may lead to non-assignment of a codebook index. Preferred embodiments fix the problem with default or limited random variable assignments or flagging the overflow and adjusting the frame encoding such as by limiting spectral components or changing quantization targets.

摘要翻译： 在G.729附录B语音编码中LSF量化的溢出问题可能导致码本索引的非赋值。 优选实施例用默认或有限的随机变量分配来解决问题，或者通过限制频谱分量或改变量化目标来标记溢出并调整帧编码。

公开(公告)号：US07302387B2

公开(公告)日：2007-11-27

申请号：US10160122

申请日：2002-06-04

申请人： Dunling Li ,  Gokhan Sisli

发明人： Dunling Li ,  Gokhan Sisli

IPC分类号： G10L10/12

CPC分类号： G10L19/12 ,  G10L2019/0013

摘要： ITU Recommendation G.729 Annex E teaches in the implementation of a fixed codebook search to determine the selected sample combination providing the minimal difference between the original input speech and the reconstructed speech after implementation of the codec. A large number of sample sets are processed and the difference between the original input signal and the reconstructed signal for each set is determined and stored in a register. Under certain conditions, the register can overflow resulting in invalid difference values. When such a condition occurs, the fixed codebook search cannot determine the sample combination providing the minimal mean square error between the weighted input speech and the weighted reconstructed speech. An initialization vector for the codvec vector is used to provide valid data which conforms to the G.729 Annex E specifications and minimizes changes to the G.729 source code while providing robust quality signal processing in the event of register overflow condition.

摘要翻译： 国际电联ITU G.729建议书附件E教导了固定码本搜索的实现，以确定在实现编解码器之后提供原始输入语音与重构语音之间的最小差异的所选样本组合。 处理大量样本集，并且确定每个组的原始输入信号和重构信号之间的差并将其存储在寄存器中。 在某些情况下，寄存器可能溢出，导致无效的差值。 当出现这种情况时，固定码本搜索不能确定提供加权输入语音和加权重构语音之间的最小均方误差的样本组合。 用于编码矢量的初始化向量用于提供符合G.729附录E规范的有效数据，并最大限度地减少G.729源代码的改变，同时在寄存器溢出情况下提供稳健的质量信号处理。

公开(公告)号：US06807525B1

公开(公告)日：2004-10-19

申请号：US09699366

申请日：2000-10-31

申请人： Dunling Li ,  Gokhan Sisli ,  Daniel Thomas

发明人： Dunling Li ,  Gokhan Sisli ,  Daniel Thomas

IPC分类号： G10L1106

CPC分类号： G10L19/012

摘要： A method to reduce the amount of bandwidth used in the transmission of digitized voice packets is described. The method is used to reduce the number of transmitted packets by suspending transmission during periods of silence or when only noise is present. The system determines if a background noise update is warranted based on human auditory perception factors instead of an artificial limiter on excessive silence insertion descriptor packets. The system searches for characteristics in the perceptual changes of background noise instead of analyzing speech for improved audio compression. The invention weighs factors affecting the perception of sound including frequency masking, temporal masking, loudness perception based on tone, and auditory perception differential based on tone.

摘要翻译： 描述了减少数字化语音分组传输中使用的带宽量的方法。 该方法用于通过在静默期间或当仅存在噪声时暂停传输来减少发送分组的数量。 系统基于人类听觉感知因素来确定背景噪声更新是否有保证，而不是在过度沉默插入描述符分组上的人造限制器。 系统搜索背景噪声感知变化中的特征，而不是分析语音以改进音频压缩。 本发明重影影响声音感知的因素，包括频率屏蔽，时间屏蔽，基于音调的响度感知，以及基于音调的听觉感知差异。