Code excited linear prediction speech coding system
    1.
    发明授权
    Code excited linear prediction speech coding system 失效
    码激励线性预测语音编码系统

    公开(公告)号:US5261027A

    公开(公告)日:1993-11-09

    申请号:US997667

    申请日:1992-12-28

    CPC分类号: G10L19/12 G10L25/93

    摘要: A code excited linear prediction (CELP) type speech signal coding system is provided, a code vector obtained by applying linear prediction to a vector of a residual speech signal of white noise is stored in a code book. A pitch prediction vector obtained by applying linear prediction to a residual signal of a preceding frame is given a delay corresponding to a pitch frequency and added to the code vector. Use is made of an impulse vector obtained by applying linear prediction to a residual signal vector of impulses having a predetermined relationship with the vectors of the white noise code book. Variable gains are given to at least the above code vector and impulse vector, a reproduced signal is produced, and this reproduced signal is used for identification of the input speech signal. Thus, a pulse series corresponding to the sound source of voiced speech sounds is created.

    摘要翻译: 提供码激励线性预测(CELP)型语音信号编码系统,通过对白噪声的残留语音信号的向量应用线性预测而获得的码矢量被存储在码本中。 通过对前一帧的残差信号应用线性预测而获得的音调预测矢量被给予对应于音调频率的延迟并被加到码矢量。 使用通过对与白噪声码本的矢量具有预定关系的脉冲的残差信号矢量应用线性预测而获得的脉冲矢量。 至少对上述代码矢量和脉冲矢量赋予可变增益,产生再生信号,该再现信号用于识别输入语音信号。 因此,产生对应于有声语音的声源的脉冲序列。

    Speech coding apparatus using multimode coding
    3.
    发明授权
    Speech coding apparatus using multimode coding 失效
    使用多模式编码的语音编码设备

    公开(公告)号:US5224167A

    公开(公告)日:1993-06-29

    申请号:US580669

    申请日:1990-09-11

    IPC分类号: H03M13/00 G10L19/14 H04L1/20

    CPC分类号: G10L19/18 H04L1/20

    摘要: A speech coding apparatus coupled to a transmission channel includes m (m is an integer greater than 1) coders, m decoders and m or (m-1) error correcting coders. The apparatus also includes an evaluation unit which evaluates a quality of each of reproduced speech signals from the input speech signal and the reproduced speech signals and which outputs an evaluated quality of each of the reproduced speech signals. The quality of each of the reproduced speech signals is evaluated in a state having no transmission error. A decision unit identifies one of the m coders which provides the reproduced speech signal having a smallest distortion on the basis of the evaluated quality of each of the reproduced speech signals, a current error rate of the transmission channel and error correcting abilities of the error correcting coders, and generates a coder identification number representative of a selected one of the m coders. An output part outputs a multiplexed transmission signal including the coded speech signal generated by the one of the m coders identified by the decision unit and the error correcting code generated by a corresponding one of the m error correcting coders.

    Gain-shape vector quantization method and apparatus
    5.
    发明授权
    Gain-shape vector quantization method and apparatus 失效
    增益矢量量化方法及装置

    公开(公告)号:US5263119A

    公开(公告)日:1993-11-16

    申请号:US795668

    申请日:1991-11-21

    摘要: A gain-shape vector quantization apparatus is provided for encoding and decoding, to transmit and receive compressed speech signals. A selected plurality of vectors are read from a code book based upon an index signal. The vectors are added in an adder and synthesis filtered by a synthesis filter, in either order, to produce an output. This output is subtracted from an input speech signal to produce an error signal. An evaluation unit produces an index to select the plurality of vectors read from the code book memory based on the error signal in order to minimize this error signal. The evaluation unit produces gain adjusting signals which can be used to adjust gains of the vectors read from the code book. In an encoder, signals indicative of the gain adjusting signal and the index signal are transmitted by a transmitter of the encoder to send a quantized speech signal to a receiver of a decoder. In the decoder, after the signals indicative of the gain adjusting signal and the index are received by the receiver of the decoder, an index and gain adjusting signal is derived for use to control reading of vectors from a code book and gains thereon to reproduce the speech signal.

    摘要翻译: 增益形矢量量化装置被提供用于编码和解码,以发送和接收压缩的语音信号。 基于索引信号,从码本读取所选择的多个向量。 向量以加法器的形式加到合成滤波器中,并以合成滤波器的顺序进行合成,以产生输出。 从输入语音信号中减去该输出以产生误差信号。 评估单元基于误差信号产生用于选择从码本存储器读取的多个向量的索引,以使该误差信号最小化。 评估单元产生可用于调整从码本读取的向量的增益的增益调整信号。 在编码器中,指示增益调整信号和索引信号的信号由编码器的发射器发送,以将量化的语音信号发送到解码器的接收机。 在解码器中,在由解码器的接收器接收到指示增益调整信号和索引的信号之后,导出索引和增益调整信号以用于控制来自码本的向量的读取并在其上进行增益以再现 语音信号。

    Speech encoding/decoding apparatus having selected encoders
    6.
    发明授权
    Speech encoding/decoding apparatus having selected encoders 失效
    语音编码/解码器具有选定的编码器

    公开(公告)号:US5115469A

    公开(公告)日:1992-05-19

    申请号:US460099

    申请日:1990-02-08

    CPC分类号: G10L19/06 G10L19/04

    摘要: Several encoders perform a local decoding of a speech signal and extract excitation information and vocal tract information from a speech signal for an encoding operation. The transmission rate ratio between the excitation information and the vocal tract information are different for each encoder. An evaluation/selection unit evaluates the quality of decoded signals subjected to a local decoding in each of the encoders, determines the most suitable encoders from among the several encoders based on the result of the evaluation, and selects the most suitable encoder, thereby outputting the selection result as selection information. The decoder decodes a speech signal based on selection information, vocal tract information and excitation information. The evaluation/selection unit selects the output from the encoder in which the quality of a locally decoded signal is the most preferable. When vocal tract information changes little, the vocal tract information is not output, thereby allowing for increased quality of information. As much of the surplus of unused vocal tract information as possible is assigned to a residual signal. Thus, the quality of a decoded speech signal is improved.

    摘要翻译: PCT No.PCT / JP89 / 00580 Sec。 371日期1990年2月8日 102(e)1990年2月8日PCT PCT 1989年6月7日PCT公布。 出版物WO89 / 12292 日期为1989年12月14日。几个编码器执行语音信号的本地解码,并从用于编码操作的语音信号中提取激励信息和声道信息。 激励信息和声道信息之间的传输速率比对于每个编码器是不同的。 评估/选择单元评估在每个编码器中经过本地解码的解码信号的质量,基于评估结果从多个编码器中确定最合适的编码器,并且选择最合适的编码器,从而输出 选择结果作为选择信息。 解码器基于选择信息,声道信息和激励信息来解码语音信号。 评估/选择单元选择编码器的输出,其中本地解码信号的质量是最优选的。 当声道信息变化较小时,不输出声道信息,从而允许提高信息质量。 尽可能多的未使用的声道信息的剩余被分配给残余信号。 因此,提高了解码语音信号的质量。

    Speech coding apparatus
    7.
    发明授权
    Speech coding apparatus 失效
    语音编码设备

    公开(公告)号:US5138662A

    公开(公告)日:1992-08-11

    申请号:US508553

    申请日:1990-04-13

    IPC分类号: G10L19/00 G10L19/12 H03M7/30

    CPC分类号: G10L19/12

    摘要: A speech coding apparatus which selects an optimum code from a code book, the optimum code giving the minimum magnitude of error signal between the input signal and the reproduced signal obtained by a filter calculation using a linear prediction parameter from a linear predictive analysis unit with respect to the codes of the code book, wherein the code book is formed by thinning to 1/M (M being an integer of two or more) the plurality of sampling values constituting the codes. To compensate for the deterioration of the quality of the reproduced signal caused by thinning the sampling values in this way, an additional linear predictive analysis unit is further introduced and use made of an amended linear prediction parameter instead of the linear prediction parameter from the originally provided linear predictive analysis unit.

    Speech encoding method and apparatus using tree-structure delta code book
    10.
    发明授权
    Speech encoding method and apparatus using tree-structure delta code book 失效
    语音编码方法和装置使用树结构三角码书

    公开(公告)号:US5864650A

    公开(公告)日:1999-01-26

    申请号:US762694

    申请日:1996-12-12

    IPC分类号: G10L19/00 G10L19/04 G10L3/02

    CPC分类号: G10L19/04

    摘要: A larger number, L', of delta vectors .DELTA..sub.i (i=0, 1, 2, . . . , L'-1) than the required number L are each multiplied by a matrix of a linear predictive synthesis filter (3), their power (A.DELTA..sub.i).sup.T (A.DELTA..sub.i) is evaluated (42), and the delta vectors are reordered in decreasing order of power (43); then, L delta vectors are selected in decreasing order of power, the largest power first, to construct a tree-structure data code book (41), using which A-b-S vector quantization is performed (48). This provides increased freedom for the space formed by the delta vectors and improves quantization characteristics. Further, variable rate encoding is achieved by taking advantage of the structure of the tree-structure data code book.

    摘要翻译: 每个乘以线性预测合成滤波器(3)的矩阵,将大于所需数量L的Δ向量DELTA i(i = 0,1,2,...,L'-1)的较大数量L' ,评估其功率(A DELTA i)T(A DELTA i)(42),并且以递减的功率顺序对增量向量重新排序(43); 然后,以降序的功率,最大功率先选择L个增量向量,构建一个树结构数据码本(41),利用其中的A-b-S矢量量化进行(48)。 这提供了由Δ向量形成的空间的增加的自由度并且提高了量化特性。 此外,通过利用树结构数据码本的结构来实现可变速率编码。