c1035pf.cpp

实现3GPP的GSM中AMR语音的CODECS。

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 * 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
 *
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 * 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.
****************************************************************************************/
/*
------------------------------------------------------------------------------



 Pathname: ./audio/gsm-amr/c/src/c1035pf.c
 Functions: q_p
            build_code
            code_10i40_35bits


     Date: 09/28/2000

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

 Description: Updated template. Cleaned up code. Passing in a pointer to
              overflow flag for build_code() and code_10i40_35bits() functions.
              Removed unnecessary header files.

 Description:
              1. Eliminated unused include files.
              2. Replaced array addressing by pointers
              3. Eliminated math operations that unnecessary checked for
                 saturation
              4. Replaced for-loops with memset()

 Description: Changed function name to pv_round to avoid conflict with
              round function in C standard library.

 Description:  Replaced OSCL mem type functions and eliminated include
               files that now are chosen by OSCL definitions

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

 Description:

------------------------------------------------------------------------------
 MODULE DESCRIPTION

 This file contains the function that searches a 35 bit algebraic codebook
 containing 10 pulses in a frame of 40 samples.

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

/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/
#include "c1035pf.h"
#include "cnst.h"
#include "basic_op.h"
#include "inv_sqrt.h"
#include "set_sign.h"
#include "cor_h.h"
#include "cor_h_x.h"
#include "s10_8pf.h"
#include "oscl_mem.h"

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


/*----------------------------------------------------------------------------
; DEFINES
; [Include all pre-processor statements here. Include conditional
; compile variables also.]
----------------------------------------------------------------------------*/
#define NB_PULSE  10

/*----------------------------------------------------------------------------
; LOCAL FUNCTION DEFINITIONS
; [List function prototypes here]
----------------------------------------------------------------------------*/

/*----------------------------------------------------------------------------
; LOCAL VARIABLE DEFINITIONS
; [Variable declaration - defined here and used outside this module]
----------------------------------------------------------------------------*/

/*
------------------------------------------------------------------------------
 FUNCTION NAME: q_p
------------------------------------------------------------------------------
 INPUT AND OUTPUT DEFINITIONS

 Inputs:
    pShift_reg = pointer to Old CN generator shift register state (Word32)
    no_bits = Number of bits (Word16)

 Outputs:
    pShift_reg -> Updated CN generator shift register state

 Returns:
    noise_bits = Generated random integer value (Word16)

 Global Variables Used:
    None

 Local Variables Needed:
    None

------------------------------------------------------------------------------
 FUNCTION DESCRIPTION

 This is a local function that determnes the index of the pulses by looking up
 the gray encoder table

------------------------------------------------------------------------------
 REQUIREMENTS

 None

------------------------------------------------------------------------------
 REFERENCES

 c1035pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001

------------------------------------------------------------------------------
 PSEUDO-CODE

void q_p (
    Word16 *ind,        // Pulse position
    Word16 n            // Pulse number
)
{
    Word16 tmp;

    tmp = *ind;

    if (sub (n, 5) < 0)
    {
        *ind = (tmp & 0x8) | gray[tmp & 0x7];
    }
    else
    {
        *ind = gray[tmp & 0x7];
    }
}

------------------------------------------------------------------------------
 RESOURCES USED [optional]

 When the code is written for a specific target processor the
 the resources used should be documented below.

 HEAP MEMORY USED: x bytes

 STACK MEMORY USED: x bytes

 CLOCK CYCLES: (cycle count equation for this function) + (variable
                used to represent cycle count for each subroutine
                called)
     where: (cycle count variable) = cycle count for [subroutine
                                     name]

------------------------------------------------------------------------------
 CAUTION [optional]
 [State any special notes, constraints or cautions for users of this function]

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

/*----------------------------------------------------------------------------
; FUNCTION CODE
----------------------------------------------------------------------------*/

void q_p(
    Word16 *pInd,       /* Pulse position */
    Word16 n            /* Pulse number   */
)
{
    Word16 tmp;

    tmp = *pInd;

    if (n < 5)
    {
        *pInd = (tmp & 0x8) | gray[tmp & 0x7];
    }
    else
    {
        *pInd = gray[tmp & 0x7];
    }
}

/*
------------------------------------------------------------------------------
 FUNCTION NAME: build_code
------------------------------------------------------------------------------
 INPUT AND OUTPUT DEFINITIONS

 Inputs:
    pSeed = pointer to the Old CN generator shift register state (Word32)
    n_param = Number of parameters to randomize (Word16)
    param_size_table = table holding paameter sizes (Word16)
    param[] = array to hold CN generated paramters (Word16)
    pOverflow = pointer to overflow flag (Flag)

 Outputs:
    param[] = CN generated parameters (Word16)
    pSeed = Updated CN generator shift register state (Word16)
    pOverflow -> 1 if overflow occured

 Returns:
    None

 Global Variables Used:
    None

 Local Variables Needed:
    None

------------------------------------------------------------------------------
 FUNCTION DESCRIPTION

 This function builds the codeword, the filtered codeword and index of the
 codevector, based on the signs and positions of 10 pulses.
------------------------------------------------------------------------------
 REQUIREMENTS

 None

------------------------------------------------------------------------------
 REFERENCES

 c1035pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001

------------------------------------------------------------------------------
 PSEUDO-CODE
static void build_code (
    Word16 codvec[],    // (i)  : position of pulses
    Word16 sign[],      // (i)  : sign of d[n]
    Word16 cod[],       // (o)  : innovative code vector
    Word16 h[],         // (i)  : impulse response of weighted synthesis filter
    Word16 y[],         // (o)  : filtered innovative code
    Word16 indx[]       // (o)  : index of 10 pulses (sign+position)
)
{
    Word16 i, j, k, track, index, _sign[NB_PULSE];
    Word16 *p0, *p1, *p2, *p3, *p4, *p5, *p6, *p7, *p8, *p9;
    Word32 s;

    for (i = 0; i < L_CODE; i++)
    {
        cod[i] = 0;
    }
    for (i = 0; i < NB_TRACK; i++)
    {
        indx[i] = -1;
    }

    for (k = 0; k < NB_PULSE; k++)
    {
        // read pulse position
        i = codvec[k];
        // read sign
        j = sign[i];

        index = mult (i, 6554);                  // index = pos/5
        // track = pos%5
        track = sub (i, extract_l (L_shr (L_mult (index, 5), 1)));

        if (j > 0)
        {
            cod[i] = add (cod[i], 4096);
            _sign[k] = 8192;

        }
        else
        {
            cod[i] = sub (cod[i], 4096);
            _sign[k] = -8192;
            index = add (index, 8);
        }

        if (indx[track] < 0)
        {
            indx[track] = index;
        }
        else
        {
            if (((index ^ indx[track]) & 8) == 0)
            {
                // sign of 1st pulse == sign of 2nd pulse

                if (sub (indx[track], index) <= 0)
                {
                    indx[track + 5] = index;
                }
                else
                {
                    indx[track + 5] = indx[track];
                    indx[track] = index;
                }
            }
            else
            {
                // sign of 1st pulse != sign of 2nd pulse

                if (sub ((Word16)(indx[track] & 7), (Word16)(index & 7)) <= 0)
                {
                    indx[track + 5] = indx[track];
                    indx[track] = index;
                }
                else
                {
                    indx[track + 5] = index;