xref: /frameworks/av/media/libstagefright/codecs/amrnb/dec/src/d8_31pf.cpp

/* ------------------------------------------------------------------
 * Copyright (C) 1998-2009 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.
****************************************************************************************/
/*
------------------------------------------------------------------------------



 Pathname: ./audio/gsm-amr/c/src/d8_31pf.c
 Functions:


     Date: 01/28/2002

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

 Description: Modified to pass overflow flag through to basic math function.
 The flag is passed back to the calling function by pointer reference.

 Description: Per review comments...
 (1) Removed include of "count.h" and "basic_op.h"
 (2) Added includes of mult.h, shl.h, shr.h, add.h, sub.h, negate.h,
     L_mult.h, and L_shr.h

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

 Description:

------------------------------------------------------------------------------
 MODULE DESCRIPTION
*/

/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/
#include "d8_31pf.h"
#include "typedef.h"
#include "basic_op.h"
#include "cnst.h"


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

/*----------------------------------------------------------------------------
; DEFINES
; Include all pre-processor statements here. Include conditional
; compile variables also.
----------------------------------------------------------------------------*/
#define NB_PULSE  8           /* number of pulses  */

/* define values/representation for output codevector and sign */
#define POS_CODE  8191
#define NEG_CODE  8191


/*----------------------------------------------------------------------------
; LOCAL FUNCTION DEFINITIONS
; Function Prototype declaration
----------------------------------------------------------------------------*/

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

/*
------------------------------------------------------------------------------
 FUNCTION NAME: decompress10
------------------------------------------------------------------------------
 INPUT AND OUTPUT DEFINITIONS

 Inputs:
   MSBs -- Word16 -- MSB part of the index
   LSBs -- Word16 -- LSB part of the index
   index1 -- Word16 -- index for first pos in pos_index[]
   index2 -- Word16 -- index for second pos in pos_index[]
   index3 -- Word16 -- index for third pos in pos_index[]

 Outputs:
   pos_indx[] -- array of type Word16 -- position of 3 pulses (decompressed)

   pOverflow  Flag set when overflow occurs, pointer of type Flag *

 Returns:
    None

 Global Variables Used:
    None

 Local Variables Needed:
    None

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


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

 None

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

 d8_31pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001

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


------------------------------------------------------------------------------
 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]

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

static void decompress10(
    Word16 MSBs,        /* i : MSB part of the index                 */
    Word16 LSBs,        /* i : LSB part of the index                 */
    Word16 index1,      /* i : index for first pos in pos_index[]    */
    Word16 index2,      /* i : index for second pos in pos_index[]   */
    Word16 index3,      /* i : index for third pos in pos_index[]    */
    Word16 pos_indx[],  /* o : position of 3 pulses (decompressed)   */
    Flag  *pOverflow)   /* o : Flag set when overflow occurs         */
{
    Word16 ia;
    Word16 ib;
    Word16 ic;
    Word32 tempWord32;

    /*
      pos_indx[index1] = ((MSBs-25*(MSBs/25))%5)*2 + (LSBs-4*(LSBs/4))%2;
      pos_indx[index2] = ((MSBs-25*(MSBs/25))/5)*2 + (LSBs-4*(LSBs/4))/2;
      pos_indx[index3] = (MSBs/25)*2 + LSBs/4;
    */

    if (MSBs > 124)
    {
        MSBs = 124;
    }

    ia =
        mult(
            MSBs,
            1311,
            pOverflow);

    tempWord32 =
        L_mult(
            ia,
            25,
            pOverflow);


    ia = (Word16)(MSBs - (tempWord32 >> 1));
    ib =
        mult(
            ia,
            6554,
            pOverflow);

    tempWord32 =
        L_mult(
            ib,
            5,
            pOverflow);

    ib = ia - (Word16)(tempWord32 >> 1);

    ib =
        shl(
            ib,
            1,
            pOverflow);


    ic = LSBs - ((LSBs >> 2) << 2);


    pos_indx[index1] = ib + (ic & 1);


    ib =
        mult(
            ia,
            6554,
            pOverflow);

    ib =
        shl(
            ib,
            1,
            pOverflow);


    pos_indx[index2] = ib + (ic >> 1);


    ib = LSBs >> 2;

    ic =
        mult(
            MSBs,
            1311,
            pOverflow);

    ic =
        shl(
            ic,
            1,
            pOverflow);

    pos_indx[index3] =
        add(
            ib,
            ic,
            pOverflow);

    return;
}


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

 Inputs:
    indx[] -- array of type Word16 -- position and sign of
                                      8 pulses (compressed)

 Outputs:
    sign_indx[] -- array of type Word16 -- signs of 4 pulses (signs only)
    pos_indx[]  -- array of type Word16 -- position index of 8 pulses
                                           (position only)
    pOverflow pointer to type Flag -- Flag set when overflow occurs

 Returns:
    None

 Global Variables Used:
    None

 Local Variables Needed:
    None

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

    PURPOSE: decompression of the linear codewords to 4+three indeces
             one bit from each pulse is made robust to errors by
             minimizing the phase shift of a bit error.
             4 signs (one for each track)
             i0,i4,i1 => one index (7+3) bits, 3   LSBs more robust
             i2,i6,i5 => one index (7+3) bits, 3   LSBs more robust
             i3,i7    => one index (5+2) bits, 2-3 LSbs more robust

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

 None

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

 d8_31pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001

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


------------------------------------------------------------------------------
 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]

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

static void decompress_code(
    Word16 indx[],      /* i : position and sign of 8 pulses (compressed) */
    Word16 sign_indx[], /* o : signs of 4 pulses (signs only)             */
    Word16 pos_indx[],  /* o : position index of 8 pulses (position only) */
    Flag  *pOverflow    /* o : Flag set when overflow occurs              */
)
{
    Word16 i;
    Word16 ia;
    Word16 ib;
    Word16 MSBs;
    Word16 LSBs;
    Word16 MSBs0_24;
    Word32 tempWord32;

    for (i = 0; i < NB_TRACK_MR102; i++)
    {
        sign_indx[i] = indx[i];
    }

    /*
      First index: 10x10x10 -> 2x5x2x5x2x5-> 125x2x2x2 -> 7+1x3 bits
      MSBs = indx[NB_TRACK]/8;
      LSBs = indx[NB_TRACK]%8;
      */
    MSBs = indx[NB_TRACK_MR102] >> 3;

    LSBs = indx[NB_TRACK_MR102] & 0x7;

    decompress10(
        MSBs,
        LSBs,
        0,
        4,
        1,
        pos_indx,
        pOverflow);

    /*
      Second index: 10x10x10 -> 2x5x2x5x2x5-> 125x2x2x2 -> 7+1x3 bits
      MSBs = indx[NB_TRACK+1]/8;
      LSBs = indx[NB_TRACK+1]%8;
      */
    MSBs = indx[NB_TRACK_MR102+1] >> 3;

    LSBs = indx[NB_TRACK_MR102+1] & 0x7;

    decompress10(
        MSBs,
        LSBs,
        2,
        6,
        5,
        pos_indx,
        pOverflow);

    /*
      Third index: 10x10 -> 2x5x2x5-> 25x2x2 -> 5+1x2 bits
      MSBs = indx[NB_TRACK+2]/4;
      LSBs = indx[NB_TRACK+2]%4;
      MSBs0_24 = (MSBs*25+12)/32;
      if ((MSBs0_24/5)%2==1)
         pos_indx[3] = (4-(MSBs0_24%5))*2 + LSBs%2;
      else
         pos_indx[3] = (MSBs0_24%5)*2 + LSBs%2;
      pos_indx[7] = (MSBs0_24/5)*2 + LSBs/2;
      */

    MSBs = indx[NB_TRACK_MR102+2] >> 2;

    LSBs = indx[NB_TRACK_MR102+2] & 0x3;

    tempWord32 =
        L_mult(
            MSBs,
            25,
            pOverflow);

    ia =
        (Word16)
        L_shr(
            tempWord32,
            1,
            pOverflow);

    ia += 12;

    MSBs0_24 = ia >> 5;


    ia =
        mult(
            MSBs0_24,
            6554,
            pOverflow);

    ia &= 1;


    ib =
        mult(
            MSBs0_24,
            6554,
            pOverflow);

    tempWord32 =
        L_mult(
            ib,
            5,
            pOverflow);


    ib = MSBs0_24 - (Word16)(tempWord32 >> 1);

    if (ia == 1)
    {
        ib = 4 - ib;

    }


    ib =
        shl(
            ib,
            1,
            pOverflow);

    ia = LSBs & 0x1;

    pos_indx[3] =
        add(
            ib,
            ia,
            pOverflow);

    ia =
        mult(
            MSBs0_24,
            6554,
            pOverflow);

    ia =
        shl(
            ia,
            1,
            pOverflow);

    pos_indx[7] = ia + (LSBs >> 1);

}

/*
------------------------------------------------------------------------------
 FUNCTION NAME: dec_8i40_31bits
------------------------------------------------------------------------------
 INPUT AND OUTPUT DEFINITIONS

 Inputs:
    index   array of type Word16 --  index of 8 pulses (sign+position)

 Outputs:
    cod     array of type Word16 --  algebraic (fixed) codebook excitation
    pOverflow pointer to type Flag -- Flag set when overflow occurs

 Returns:
    None

 Global Variables Used:
    None

 Local Variables Needed:
    None

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

 PURPOSE:  Builds the innovative codevector from the received
           index of algebraic codebook.

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

 None

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

 d8_31pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001

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


------------------------------------------------------------------------------
 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]

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

void dec_8i40_31bits(
    Word16 index[],    /* i : index of 8 pulses (sign+position)         */
    Word16 cod[],      /* o : algebraic (fixed) codebook excitation     */
    Flag  *pOverflow   /* o : Flag set when overflow occurs             */
)
{
    Word16 i;
    Word16 j;
    Word16 pos1;
    Word16 pos2;
    Word16 sign;

    Word16 linear_signs[NB_TRACK_MR102];
    Word16 linear_codewords[NB_PULSE];

    for (i = 0; i < L_CODE; i++)
    {
        cod[i] = 0;
    }

    decompress_code(
        index,
        linear_signs,
        linear_codewords,
        pOverflow);

    /* decode the positions and signs of pulses and build the codeword */
    for (j = 0; j < NB_TRACK_MR102; j++)    /* NB_TRACK_MR102 = 4 */
    {
        /* position of pulse "j" */

        pos1 = (linear_codewords[j] << 2) + j;


        if (linear_signs[j] == 0)
        {
            sign = POS_CODE; /* +1.0 */
        }
        else
        {
            sign = -NEG_CODE; /* -1.0 */
        }

        if (pos1 < L_SUBFR)
        {
            cod[pos1] = sign;    /* avoid buffer overflow */
        }

        /* compute index i */
        /* position of pulse "j+4" */

        pos2 = (linear_codewords[j + 4] << 2) + j;


        if (pos2 < pos1)
        {
            sign = negate(sign);
        }

        if (pos2 < L_SUBFR)
        {
            cod[pos2] += sign;     /* avoid buffer overflow */
        }


    } /* for (j = 0; j < NB_TRACK_MR102; j++) */

    return;
}