Multi-segment vector quantizer for a speech coder suitable for use in a
radiotelephone
    2.
    发明授权
    Multi-segment vector quantizer for a speech coder suitable for use in a radiotelephone 失效
    适用于无线电话机的语音编码器的多段矢量量化器

    公开(公告)号:US5675702A

    公开(公告)日:1997-10-07

    申请号:US611608

    申请日:1996-03-08

    摘要: A Vector-Sum Excited Linear Predictive Coding (VSELP) speech coder provides improved quality and reduced complexity over a typical speech coder. VSELP uses a codebook which has a predefined structure such that the computations required for the codebook search process can be significantly reduced. This VSELP speech coder uses single or multi-segment vector quantizer of the reflection coefficients based on a Fixed-Point-Lattice-Technique (FLAT). Additionally, this speech coder uses a pre-quantizer to reduce the vector codebook search complexity and a high-resolution scalar quantizer to reduce the amount of memory needed to store the reflection coefficient vector codebooks. Resulting in a high quality speech coder with reduced computations and storage requirements.

    摘要翻译: 矢量和激励线性预测编码(VSELP)语音编码器通过典型的语音编码器提供了改进的质量和降低的复杂度。 VSEL​​P使用具有预定义结构的码本,使得可以显着减少码本搜索处理所需的计算。 该VSELP语音编码器使用基于固定点格式技术(FLAT)的反射系数的单段或多段矢量量化器。 此外,该语音编码器使用预量化器来减少矢量码本搜索复杂度和高分辨率标量量化器,以减少存储反射系数矢量码本所需的存储量。 产生了一个高质量的语音编码器,减少了计算和存储要求。

    Method for generating a spectral noise weighting filter for use in a
speech coder
    3.
    发明授权
    Method for generating a spectral noise weighting filter for use in a speech coder 失效
    用于产生用于语音编码器的频谱噪声加权滤波器的方法

    公开(公告)号:US5570453A

    公开(公告)日:1996-10-29

    申请号:US434868

    申请日:1995-05-04

    CPC分类号: G10L19/12

    摘要: A digital speech coding method uses an Rth-order filter to model the frequency response of multiple filters, thereby, providing a filter which offers the control of multiple filters without the complexity of multiple filters. The Rth-order filter can be used as a spectral noise weighting filter or a combination of a short-term predictor filter and a spectral noise weighting filter, referred to as the spectrally noise weighted synthesis filter, depending on which embodiment is employed. In general, the method models the frequency response of L Pth-order filters by a single Rth-order filter, where the order R

    摘要翻译: 数字语音编码方法使用R阶滤波器对多个滤波器的频率响应进行建模,从而提供一个滤波器,其提供多个滤波器的控制,而不需要多个滤波器的复杂性。 根据使用哪个实施例,R阶滤波器可以用作频谱噪声加权滤波器或短期预测器滤波器和被称为频谱噪声加权合成滤波器的频谱噪声加权滤波器的组合。 通常,该方法通过单个R阶滤波器对L P阶滤波器的频率响应建模,其中阶数R

    Method for generating a spectral noise weighting filter for use in a
speech coder
    4.
    发明授权
    Method for generating a spectral noise weighting filter for use in a speech coder 失效
    用于产生用于语音编码器的频谱噪声加权滤波器的方法

    公开(公告)号:US5434947A

    公开(公告)日:1995-07-18

    申请号:US21364

    申请日:1993-02-23

    CPC分类号: G10L19/12

    摘要: An Rth-order filter models the frequency response of multiple filters, to provide a filter which offers the control of multiple filters without the complexity of multiple filters. The Rth-order filter can be used as a spectral noise weighting filter or a combination of a short-term predictor filter and a spectral noise weighting filter, referred to as the spectrally noise weighted synthesis filter, depending on which embodiment is employed. In general, the method models the frequency response of L Pth-order filters by a single Rth-order filter, where the order R

    摘要翻译: R阶滤波器对多个滤波器的频率响应进行建模,以提供一个滤波器,可提供多个滤波器的控制,而不需要多个滤波器的复杂性。 根据使用哪个实施例,R阶滤波器可以用作频谱噪声加权滤波器或短期预测器滤波器和被称为频谱噪声加权合成滤波器的频谱噪声加权滤波器的组合。 通常,该方法通过单个R阶滤波器对L P阶滤波器的频率响应建模,其中阶数R

    Digital speech coder and method utilizing harmonic noise weighting
    6.
    发明授权
    Digital speech coder and method utilizing harmonic noise weighting 失效
    数字语音编码器和利用谐波噪声加权的方法

    公开(公告)号:US5528723A

    公开(公告)日:1996-06-18

    申请号:US303271

    申请日:1994-09-07

    IPC分类号: G10L19/00 G10L19/14 G10L3/02

    CPC分类号: G10L19/12 G10L25/90

    摘要: A digital speech coder utilizes harmonic noise weighting to overcome some limitations of low-rate CELP-type speech coders in reproducing voiced speech. In addition to a short term correction factor, which constitutes spectral noise weighting as known in the art, a long term pitch correction factor is utilized to provide harmonic noise weighting. The inclusion of harmonic noise weighting in a speech coder more efficiently utilizes noise-masking properties of a speech signal, allowing synthesis of a higher quality speech at a given bit rate.

    摘要翻译: 数字语音编码器利用谐波噪声加权来克服在再现有声语音时低速率CELP型语音编码器的一些限制。 除了构成本领域已知的频谱噪声加权的短期校正因子之外,还使用长期的音调校正因子来提供谐波噪声加权。 在语音编码器中更高效地包含谐波噪声加权,利用语音信号的噪声掩蔽特性,允许以给定比特率合成较高质量的语音。

    Digital speech decoder having a postfilter with reduced spectral
distortion
    7.
    发明授权
    Digital speech decoder having a postfilter with reduced spectral distortion 失效
    数字语音解码器具有具有降低的频谱失真的后置滤波器

    公开(公告)号:US5241650A

    公开(公告)日:1993-08-31

    申请号:US870199

    申请日:1992-04-13

    IPC分类号: G10L19/14

    CPC分类号: G10L19/26

    摘要: An adaptive spectral postfilter in a synthesized speech platform has a denominator characteristic that corresponds to a preceding LPC filter stage, and a numerator characteristic that is developed as a function of the denominator characteristic through application of spectral smoothing techniques. This allows the numerator to track the denominator without the introduction of spectral distortion that would otherwise affect the processing in an adverse way.

    摘要翻译: 合成语音平台中的自适应频谱后置滤波器具有对应于前面的LPC滤波器级的分母特征,以及通过应用频谱平滑技术作为分母特性的函数而发展的分子特征。 这允许分子跟踪分母而不引入光谱失真,否则会以不利的方式影响处理。

    Digital speech coder having optimized signal energy parameters
    8.
    发明授权
    Digital speech coder having optimized signal energy parameters 失效
    数字语音编码器具有优化的信号能量参数

    公开(公告)号:US5490230A

    公开(公告)日:1996-02-06

    申请号:US361474

    申请日:1994-12-22

    CPC分类号: G10L19/083 G10L19/125

    摘要: A speech coder and decoder methodology wherein pitch excitation and codebook excitation source energies are represented by parameters that are readily transmissible with minimal transmission capacity requirements. The parameters are the long term energy value, a short term correction factor which is applied to the long term energy value to match the short term energy, and proportionality factor(s) that specify the relative energy contribution of the excitation sources to the short term energy value.

    摘要翻译: 语音编码器和解码器方法,其中音调激励和码本激励源能量由在最小传输容量要求下容易传播的参数表示。 参数是长期能量值,应用于长期能量值以匹配短期能量的短期校正因子,以及规定激励源与短期能量的相对能量贡献的比例因子 能量值。

    Digital speech coder having improved sub-sample resolution long-term
predictor
    9.
    发明授权
    Digital speech coder having improved sub-sample resolution long-term predictor 失效
    具有改进的子样本分辨率长期预测器的数字语音编码器

    公开(公告)号:US5359696A

    公开(公告)日:1994-10-25

    申请号:US214998

    申请日:1994-03-21

    IPC分类号: G10L19/00 G10L19/12 G10L9/18

    CPC分类号: G10L19/12

    摘要: A digital speech coder includes a long-term filter (124) having an improved sub-sample resolution long-term predictor (FIG. 5 ) which allows for subsample resolution for the lag parameter L. A frame of N samples of input speech vector s(n) is applied to an adder (510). The output of the adder (510) produces the output vector b(n) for the long term filter (124). The output vector b(n) is fed back to a delayed vector generator block (530) of the long-term predictor. The nominal long-term predictor lag parameter L is also input to the delayed vector generator block (530). The long-term predictor lag parameter L can take on non-integer values, which may be multiples of one half, one third, one fourth or any other rational fraction. The delayed vector generator (530) includes a memory which holds past samples of b(n). In addition, interpolated samples of b(n) are also calculated by the delayed vector generator (530) and stored in its memory, at least one interpolated sample being calculated and stored between each past sample of b(n). The delayed vector generator (530) provides output vector q(n) to the long-term multiplier block (520), which scales the long-term predictor response by the long-term predictor coefficient .beta.. The scaled output .beta.q(n) is then applied to the adder (510) to complete the feedback loop of the recursive filter (124).

    摘要翻译: 数字语音编码器包括具有改进的子样本分辨率长期预测器(图5)的长期滤波器(124),其允许用于滞后参数L的子样本分辨率。输入语音向量s的N个样本的帧 (n)被施加到加法器(510)。 加法器(510)的输出产生用于长期滤波器(124)的输出向量b(n)。 输出向量b(n)被反馈给长期预测器的延迟向量生成器块(530)。 标称长期预测器滞后参数L也被输入到延迟向量发生器块(530)。 长期预测器滞后参数L可以采用非整数值,其可以是二分之一,三分之一,四分之一或任何其他有理分数的倍数。 延迟向量生成器(530)包括保存b(n)的过去样本的存储器。 另外,b(n)的内插样本也由延迟矢量发生器(530)计算并存储在其存储器中,至少一个内插样本被计算并存储在每个过去的样本b(n)之间。 延迟向量生成器(530)向长期乘法器块(520)提供输出向量q(n),长期乘数块(520)通过长期预测器系数β来缩放长期预测器响应。 然后将缩放的输出βq(n)加到加法器(510)以完成递归滤波器(124)的反馈回路。

    Speech encoder using a soft interpolation decision for spectral
parameters
    10.
    发明授权
    Speech encoder using a soft interpolation decision for spectral parameters 失效
    语音编码器使用光谱参数的软插值决策

    公开(公告)号:US5265219A

    公开(公告)日:1993-11-23

    申请号:US944855

    申请日:1992-09-14

    IPC分类号: G01L9/02 G10L19/00 G10L19/02

    CPC分类号: G10L19/02

    摘要: A speech encoder uses a soft interpolation decision for spectral parameters. For each frame, the encoder first calculates the residual energy for interpolated spectral parameters, and then calculates the residual energy for non-interpolated spectral parameters. The encoder then compares these residual energy calculations. If the encoder determines that the interpolated spectral parameters yields the lowest residual energy, it indicates to a far-end decoder to use the interpolated values for the current frame. Otherwise, it indicates to the far-end decoder to use the non-interpolated values for the current frame. The encoder signals the far-end decoder as to which spectral parameters (interpolated or non-interpolated values) to use by encoding and transmitting a special signalling bit.

    摘要翻译: 语音编码器对频谱参数使用软插值决定。 对于每个帧,编码器首先计算内插频谱参数的残余能量,然后计算非内插频谱参数的剩余能量。 编码器然后比较这些剩余能量计算。 如果编码器确定插值的频谱参数产生最低的残余能量,则其向远端解码器指示对当前帧使用内插值。 否则,它向远端解码器指示使用当前帧的非内插值。 编码器向远端解码器发信号通过编码和发送特殊信令位来使用哪些频谱参数(内插或非内插值)。