pvamrwbdecoder_acelp.h

实现3GPP的GSM中AMR语音的CODECS。

/* ------------------------------------------------------------------
 * Copyright (C) 2008 PacketVideo
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 * -------------------------------------------------------------------
 */
/****************************************************************************************
Portions of this file are derived from the following 3GPP standard:

    3GPP TS 26.173
    ANSI-C code for the Adaptive Multi-Rate - Wideband (AMR-WB) speech codec
    Available from http://www.3gpp.org

(C) 2007, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC)
Permission to distribute, modify and use this file under the standard license
terms listed above has been obtained from the copyright holder.
****************************************************************************************/
/*
------------------------------------------------------------------------------



 Pathname: ./cpp/include/pvamrwbdecoder_acelp.h

     Date: 01/04/2007

------------------------------------------------------------------------------
 REVISION HISTORY

 Description:
------------------------------------------------------------------------------
 INCLUDE DESCRIPTION

------------------------------------------------------------------------------
*/

#ifndef PVAMRWBDECODER_ACELP_H
#define PVAMRWBDECODER_ACELP_H


/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/

#include "pv_amr_wb_type_defs.h"
#include "pvamrwbdecoder_mem_funcs.h"

#ifdef __cplusplus
extern "C"
{
#endif

    /*-----------------------------------------------------------------*
     *                        LPC prototypes                           *
     *-----------------------------------------------------------------*/

    void isf_extrapolation(int16 HfIsf[]);

    void Init_Lagconc(int16 lag_hist[]);
    void lagconceal(
        int16 gain_hist[],                   /* (i) : Gain history     */
        int16 lag_hist[],                    /* (i) : Subframe size         */
        int16 * T0,
        int16 * old_T0,
        int16 * seed,
        int16 unusable_frame
    );

    void agc2_amr_wb(
        int16 * sig_in,                      /* input : postfilter input signal  */
        int16 * sig_out,                     /* in/out: postfilter output signal */
        int16 l_trm                          /* input : subframe size            */
    );

    void low_pass_filt_7k_init(int16 mem[]);
    void low_pass_filt_7k(
        int16 signal[],                      /* input:  signal                  */
        int16 lg,                            /* input:  length of input         */
        int16 mem[],                         /* in/out: memory (size=30)        */
        int16 x[]
    );

    int16 median5(int16 x[]);

    void Isp_Az(
        int16 isp[],                         /* (i) Q15 : Immittance spectral pairs            */
        int16 a[],                           /* (o) Q12 : predictor coefficients (order = M)   */
        int16 m,
        int16 adaptive_scaling               /* (i) 0   : adaptive scaling disabled */
        /*     1   : adaptive scaling enabled  */
    );
    void Isf_isp(
        int16 isf[],                         /* (i) Q15 : isf[m] normalized (range: 0.0<=val<=0.5) */
        int16 isp[],                         /* (o) Q15 : isp[m] (range: -1<=val<1)                */
        int16 m                              /* (i)     : LPC order                                */
    );
    void interpolate_isp(
        int16 isp_old[],                     /* input : isps from past frame              */
        int16 isp_new[],                     /* input : isps from present frame           */
        const int16 frac[],                  /* input : fraction for 3 first subfr (Q15)  */
        int16 Az[]                           /* output: LP coefficients in 4 subframes    */
    );
    void weight_amrwb_lpc(
        int16 a[],                           /* (i) Q12 : a[m+1]  LPC coefficients             */
        int16 ap[],                          /* (o) Q12 : Spectral expanded LPC coefficients   */
        int16 gamma,                         /* (i) Q15 : Spectral expansion factor.           */
        int16 m                              /* (i)     : LPC order.                           */
    );


    /*-----------------------------------------------------------------*
     *                        isf quantizers                           *
     *-----------------------------------------------------------------*/

    void Disf_ns(
        int16 * indice,                      /* input:  quantization indices                  */
        int16 * isf_q                        /* input : ISF in the frequency domain (0..0.5)  */
    );

    void Dpisf_2s_46b(
        int16 * indice,                      /* input:  quantization indices                       */
        int16 * isf_q,                       /* output: quantized ISF in frequency domain (0..0.5) */
        int16 * past_isfq,                   /* i/0   : past ISF quantizer                    */
        int16 * isfold,                      /* input : past quantized ISF                    */
        int16 * isf_buf,                     /* input : isf buffer                                                        */
        int16 bfi,                           /* input : Bad frame indicator                   */
        int16 enc_dec
    );
    void Dpisf_2s_36b(
        int16 * indice,                      /* input:  quantization indices                       */
        int16 * isf_q,                       /* output: quantized ISF in frequency domain (0..0.5) */
        int16 * past_isfq,                   /* i/0   : past ISF quantizer                    */
        int16 * isfold,                      /* input : past quantized ISF                    */
        int16 * isf_buf,                     /* input : isf buffer                                                        */
        int16 bfi,                           /* input : Bad frame indicator                   */
        int16 enc_dec
    );


    void Reorder_isf(
        int16 * isf,                         /* (i/o) Q15: ISF in the frequency domain (0..0.5) */
        int16 min_dist,                      /* (i) Q15  : minimum distance to keep             */
        int16 n                              /* (i)      : number of ISF                        */
    );

    /*-----------------------------------------------------------------*
     *                       filter prototypes                         *
     *-----------------------------------------------------------------*/

    void oversamp_12k8_to_16k_init(
        int16 mem[]                          /* output: memory (2*NB_COEF_UP) set to zeros  */
    );
    void oversamp_12k8_to_16k(
        int16 sig12k8[],                     /* input:  signal to oversampling  */