cod_amr.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 26.073
    ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec
    Available from http://www.3gpp.org

(C) 2004, 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.
****************************************************************************************/
/*
------------------------------------------------------------------------------



 Filename: /audio/gsm_amr/c/src/include/cod_amr.h

     Date: 02/07/2002

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

 Description: Added overflow flag as an element to the cod_amrState data
              structure. Corrected the function prototype declaration for
              cod_amr().

 Description:  Replaced "int" and/or "char" with OSCL defined types.

 Description: Moved _cplusplus #ifdef after Include section.

 Description:

------------------------------------------------------------------------------
 INCLUDE DESCRIPTION

       File             : cod_amr.h
       Purpose          : Main encoder routine operating on a frame basis.

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

#ifndef cod_amr_h
#define cod_amr_h "$Id $"

/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/
#include "typedef.h"
#include "cnst.h"
#include "mode.h"
#include "lpc.h"
#include "lsp.h"
#include "cl_ltp.h"
#include "gain_q.h"
#include "p_ol_wgh.h"
#include "ton_stab.h"
#include "vad.h"
#include "dtx_enc.h"

/*--------------------------------------------------------------------------*/
#ifdef __cplusplus
extern "C"
{
#endif

    /*----------------------------------------------------------------------------
    ; MACROS
    ; [Define module specific macros here]
    ----------------------------------------------------------------------------*/

    /*----------------------------------------------------------------------------
    ; DEFINES
    ; [Include all pre-processor statements here.]
    ----------------------------------------------------------------------------*/


    /*----------------------------------------------------------------------------
    ; EXTERNAL VARIABLES REFERENCES
    ; [Declare variables used in this module but defined elsewhere]
    ----------------------------------------------------------------------------*/

    /*----------------------------------------------------------------------------
    ; SIMPLE TYPEDEF'S
    ----------------------------------------------------------------------------*/

    /*----------------------------------------------------------------------------
    ; ENUMERATED TYPEDEF'S
    ----------------------------------------------------------------------------*/

    /*----------------------------------------------------------------------------
    ; STRUCTURES TYPEDEF'S
    ----------------------------------------------------------------------------*/
    /*-----------------------------------------------------------*
     *    Coder constant parameters (defined in "cnst.h")        *
     *-----------------------------------------------------------*
     *   L_WINDOW    : LPC analysis window size.                 *
     *   L_NEXT      : Samples of next frame needed for autocor. *
     *   L_FRAME     : Frame size.                               *
     *   L_FRAME_BY2 : Half the frame size.                      *
     *   L_SUBFR     : Sub-frame size.                           *
     *   M           : LPC order.                                *
     *   MP1         : LPC order+1                               *
     *   L_TOTAL7k4  : Total size of speech buffer.              *
     *   PIT_MIN7k4  : Minimum pitch lag.                        *
     *   PIT_MAX     : Maximum pitch lag.                        *
     *   L_INTERPOL  : Length of filter for interpolation        *
     *-----------------------------------------------------------*/
    typedef struct
    {
        /* Speech vector */
        Word16 old_speech[L_TOTAL];
        Word16 *speech, *p_window, *p_window_12k2;
        Word16 *new_speech;             /* Global variable */

        /* Weight speech vector */
        Word16 old_wsp[L_FRAME + PIT_MAX];
        Word16 *wsp;

        /* OL LTP states */
        Word16 old_lags[5];
        Word16 ol_gain_flg[2];

        /* Excitation vector */
        Word16 old_exc[L_FRAME + PIT_MAX + L_INTERPOL];
        Word16 *exc;

        /* Zero vector */
        Word16 ai_zero[L_SUBFR + MP1];
        Word16 *zero;

        /* Impulse response vector */
        Word16 *h1;
        Word16 hvec[L_SUBFR * 2];

        /* Substates */
        lpcState   *lpcSt;
        lspState   *lspSt;
        clLtpState *clLtpSt;
        gainQuantState  *gainQuantSt;
        pitchOLWghtState *pitchOLWghtSt;
        tonStabState *tonStabSt;
        vadState *vadSt;
        Flag dtx;
        dtx_encState *dtx_encSt;

        /* Filter's memory */
        Word16 mem_syn[M], mem_w0[M], mem_w[M];
        Word16 mem_err[M + L_SUBFR], *error;

        Word16 sharp;

        /* Overflow flag */
        Flag   overflow;

    } cod_amrState;


    /*----------------------------------------------------------------------------
    ; GLOBAL FUNCTION DEFINITIONS
    ; [List function prototypes here]
    ----------------------------------------------------------------------------*/
    /*
    **************************************************************************
    *
    *  Function    : cod_amr_init
    *  Purpose     : Allocates memory and initializes state variables
    *  Description : Stores pointer to filter status struct in *st. This
    *                pointer has to be passed to cod_amr in each call.
    *                 - initilize pointers to speech buffer
    *                 - initialize static  pointers
    *                 - set static vectors to zero
    *  Returns     : 0 on success
    *
    **************************************************************************
    */
    Word16 cod_amr_init(cod_amrState **st, Flag dtx);

    /*
    **************************************************************************
    *
    *  Function    : cod_amr_reset
    *  Purpose     : Resets state memory
    *  Returns     : 0 on success
    *
    **************************************************************************
    */
    Word16 cod_amr_reset(cod_amrState *st);

    /*
    **************************************************************************
    *
    *  Function    : cod_amr_exit
    *  Purpose     : The memory used for state memory is freed
    *  Description : Stores NULL in *st
    *
    **************************************************************************
    */
    void cod_amr_exit(cod_amrState **st);

    /***************************************************************************
     *   FUNCTION:   cod_amr_first
     *
     *   PURPOSE:  Copes with look-ahead.
     *
     *   INPUTS:
     *       No input argument are passed to this function. However, before
     *       calling this function, 40 new speech data should be copied to the
     *       vector new_speech[]. This is a global pointer which is declared in
     *       this file (it points to the end of speech buffer minus 200).
     *
     ***************************************************************************/

    Word16 cod_amr_first(cod_amrState *st,     /* i/o : State struct            */
                         Word16 new_speech[]   /* i   : speech input (L_FRAME)  */
                        );

    /***************************************************************************
     *   FUNCTION:   cod_amr
     *
     *   PURPOSE:  Main encoder routine.
     *
     *   DESCRIPTION: This function is called every 20 ms speech frame,
     *       operating on the newly read 160 speech samples. It performs the
     *       principle encoding functions to produce the set of encoded parameters
     *       which include the LSP, adaptive codebook, and fixed codebook
     *       quantization indices (addresses and gains).
     *
     *   INPUTS:
     *       No input argument are passed to this function. However, before
     *       calling this function, 160 new speech data should be copied to the
     *       vector new_speech[]. This is a global pointer which is declared in
     *       this file (it points to the end of speech buffer minus 160).
     *
     *   OUTPUTS:
     *
     *       ana[]:     vector of analysis parameters.
     *       synth[]:   Local synthesis speech (for debugging purposes)
     *
     ***************************************************************************/

    Word16 cod_amr(cod_amrState *st,         /* i/o : State struct                 */
                   enum Mode mode,           /* i   : AMR mode                     */
                   Word16 new_speech[],      /* i   : speech input (L_FRAME)       */
                   Word16 ana[],             /* o   : Analysis parameters          */
                   enum Mode *usedMode,      /* o   : used mode                    */
                   Word16 synth[]            /* o   : Local synthesis              */
                  );


#ifdef __cplusplus
}
#endif

#endif  /* _cod_amr_h_ */