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    23.
    发明专利
    未知

    公开(公告)号：DE60032006D1

    公开(公告)日：2007-01-04

    申请号：DE60032006

    申请日：2000-10-26

    Applicant: QUALCOMM INC

    Inventor： MANJUNATH SHARATH ,  DEJACO P ,  ANANTHAPADMANABHAN K ,  CHOY LUN

    IPC: G10L19/04 ,  G10L19/14 ,  G10L19/00 ,  G10L19/12 ,  H03M7/36

    Abstract: A method and apparatus for using coding scheme selection patterns in a predictive speech coder to reduce sensitivity to frame error conditions includes a speech coder configured to select from among various predictive coding modes. After a predefined number of speech frames have been predictively coded, the speech coder codes one frame with a nonpredictive coding mode or a mildly predictive coding mode. The predefined number of frames can be determined in advance from the subjective standpoint of a listener. The predefined number of frames may be varied periodically. An average coding bit rate may be maintained for the speech coder by ensuring that an average coding bit rate is maintained for each successive pattern, or group, of predictively coded speech frames including at least one nonpredictively coded or mildly predictively coded speech frame.

    CODIFICACION PERIODICA DE VOCALES.
    24.
    发明专利
    CODIFICACION PERIODICA DE VOCALES. 未知

    公开(公告)号：ES2257098T3

    公开(公告)日：2006-07-16

    申请号：ES99967508

    申请日：1999-12-21

    Applicant: QUALCOMM INC

    Inventor： MANJUNATH SHARATH ,  GARDNER WILLIAM

    IPC: G10L19/12 ,  G10L19/00 ,  G10L19/02 ,  G10L19/04 ,  G10L19/08 ,  H03M7/30

    Abstract: Un método para codificar una señal de voz cuasi periódica, en donde la señal de voz se representa por una señal residual generada filtrando la señal de voz con un el filtro de análisis de Codificación Predictiva Lineal (LPC), y donde la señal residual se divide en tramas de datos, comprendiendo los pasos de: (a) extraer (1002) periodo representativo de una trama actual de la señal residual como prototipo actual; (b) calcular (1004) un primer juego de parámetros que describen cómo modificar un prototipo anterior de forma que dicho prototipo anterior modificado se aproxime a dicho prototipo actual; (c) seleccionar (1006) uno o más vectores de código de un primer libro de claves, donde dichos vectores de código cuando se suman aproximan la diferencia entre dicho prototipo actual y dicho prototipo anterior modificado, y donde dichos vectores de código son descritos por un segundo juego de parámetros; (d) reconstruir (1010) un prototipo actual basado en dichos primero y segundo juegos de parámetros; (e) interpolar (1012) la señal residual en la región entre dicho prototipo actual reconstruido y un prototipo reconstruido anterior; (f) sintetizar una señal de voz de salida basada en dicha señal residual interpolada.

    CODIGO INTERPOLATIVO MULTIPULSO DE TRAMAS DE VOZ.
    25.
    发明专利
    CODIGO INTERPOLATIVO MULTIPULSO DE TRAMAS DE VOZ. 未知

    公开(公告)号：ES2253226T3

    公开(公告)日：2006-06-01

    申请号：ES00930512

    申请日：2000-05-08

    Applicant: QUALCOMM INC

    Inventor： DAS AMITAVA ,  MANJUNATH SHARATH

    IPC: G10L19/10 ,  G10L19/04 ,  G10L19/14 ,  G10L19/18 ,  H03M7/30

    Abstract: Un método para codificar tramas transicionales de voz que incluye los pasos de: representar una primera trama de muestras de voz transicional mediante un primer subconjunto de muestras (402, 416) de la primera trama ; e interpolar (420) el primer subconjunto de muestras (402, 416) y un segundo subconjunto alineado de muestras (418) extraído de una segunda trama anteriormente recibida de muestras de voz transicional para sintetizar otras muestras de la primera trama que no están incluidas en el primer subconjunto.

    26.
    发明专利
    未知

    公开(公告)号：AT286617T

    公开(公告)日：2005-01-15

    申请号：AT99958940

    申请日：1999-11-12

    Applicant: QUALCOMM INC

    Inventor： DAS AMITAVA ,  MANJUNATH SHARATH

    IPC: G10L19/00 ,  G10L19/04 ,  G10L19/08 ,  G10L19/14 ,  G10L25/93 ,  H03M7/30

    Abstract: A low-bit-rate coding technique for unvoiced segments of speech includes the steps of extracting high-time-resolution energy coefficients from a frame of speech, quantizing the energy coefficients, generating a high-time-resolution energy envelope from the quantized energy coefficients, and reconstituting a residue signal by shaping a randomly generated noise vector with quantized values of the energy envelope. The energy envelope may be generated with a linear interpolation technique. A post-processing measure may be obtained and compared with a predefined threshold to determine whether the coding algorithm is performing adequately.

    BANDWIDTH-ADAPTIVE QUANTIZATION
    28.
    发明专利
    BANDWIDTH-ADAPTIVE QUANTIZATION 未知

    公开(公告)号：AU2003255247A1

    公开(公告)日：2004-02-25

    申请号：AU2003255247

    申请日：2003-08-08

    Applicant: QUALCOMM INC

    Inventor： EL-MALEH KHALED HELMI ,  KANDHADAI ANANTHAPADMANABHAN A ,  MANJUNATH SHARATH

    IPC: G10L19/12 ,  G10L19/00 ,  G10L19/02

    Abstract: Methods and apparatus are presented for determining the type of acoustic signal and the type of frequency spectrum exhibited by the acoustic signal in order to selectively delete parameter information before vector quantization. The bits that would otherwise be allocated to the deleted parameters can then be re-allocated to the quantization of the remaining parameters, which results in an improvement of the perceptual quality of the synthesized acoustic signal. Alternatively, the bits that would have been allocated to the deleted parameters are dropped, resulting in an overall bit-rate reduction.

    Method and apparatus for interleaving line spectral information quantization methods in a speech coder.
    29.
    发明专利
    Method and apparatus for interleaving line spectral information quantization methods in a speech coder. 未知

    公开(公告)号：HK1045396A1

    公开(公告)日：2002-11-22

    申请号：HK02106869

    申请日：2002-09-20

    Applicant: QUALCOMM INC

    Inventor： ANANTHAPADMANABHAN ARASANIPALA ,  MANJUNATH SHARATH

    IPC: G10L19/06 ,  G10L19/00 ,  G10L19/04 ,  H03M7/30 ,  G10L

    Abstract: A method and apparatus for interleaving line spectral information quantization methods in a speech coder includes quantizing line spectral information with two vector quantization techniques, the first technique being a non-moving-average prediction-based technique, and the second technique being a moving-average prediction-based technique. A line spectral information vector is vector quantized with the first technique. Equivalent moving average codevectors for the first technique are computed. A memory of a moving average codebook of codevectors is updated with the equivalent moving average codevectors for a predefined number of frames that were previously processed by the speech coder. A target quantization vector for the second technique is calculated based on the updated moving average codebook memory. The target quantization vector is vector quantized with the second technique to generate a quantized target codevector. The memory of the moving average codebook is updated with the quantized target codevector. Quantized line spectral information vectors are derived from the quantized target codevector.

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