q_plsf_5.cpp

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



 Pathname: ./audio/gsm-amr/c/src/q_plsf_5.c
 Funtions:

     Date: 02/05/2002

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

 Description: Placed code in the PV standard template format.
 Updated to accept new parameter, Flag *pOverflow.

 Description:
              Eliminated unused include files.
              For Vq_subvec()
              1. Eliminated math operations that unnecessary checked for
                 saturation (number are bounded to 2^12)
              2. Eliminated access to (slow) memory by using axiliar variables
              3. Because this routine is looking for the minimum distance,
                 introduced 3 check conditions inside the loop, so when the
                 partial distance is bigger than the minimun distance, the
                 loop is not completed and process continue with next iteration
              For Vq_subvec_s()
              1. Eliminated math operations that unnecessary checked for
                 saturation (number are bounded to 2^12)
              2. Combined increasing and decreasing loops to avoid double
                 accesses to the same table element
              3. Eliminated access to (slow) memory by using axiliar variables
              4. Because this routine is looking for the minimum distance,
                 introduced 2 check conditions inside the loop, so when the
                 partial distance is bigger than the minimun distance, the
                 loop is not completed and process continue with next iteration
              For Q_plsf_5()
              1. Eliminated math operations that unnecessary checked for
                 saturation (number are bounded to 2^12)
              2. Replaced array addressing by pointers

 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: Added #ifdef __cplusplus around extern'ed table.

 Description:

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


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

/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/
#include "q_plsf.h"
#include "typedef.h"
#include "basic_op.h"
#include "lsp_lsf.h"
#include "reorder.h"
#include "lsfwt.h"

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

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

    /*----------------------------------------------------------------------------
    ; DEFINES
    ; Include all pre-processor statements here. Include conditional
    ; compile variables also.
    ----------------------------------------------------------------------------*/

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

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

    /*----------------------------------------------------------------------------
    ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
    ; Declare variables used in this module but defined elsewhere
    ----------------------------------------------------------------------------*/
    /* Codebooks of LSF prediction residual */
    extern const Word16 mean_lsf_5[];

    extern const Word16 dico1_lsf_5[];
    extern const Word16 dico2_lsf_5[];
    extern const Word16 dico3_lsf_5[];
    extern const Word16 dico4_lsf_5[];
    extern const Word16 dico5_lsf_5[];

    /*--------------------------------------------------------------------------*/
#ifdef __cplusplus
}
#endif

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

 Inputs:
    lsf_r1 -- array of type Word16 -- 1st LSF residual vector,  Q15
    lsf_r2 -- array of type Word16 -- 2nd LSF residual vector,  Q15
    dico -- pointer to const Word16 -- quantization codebook,   Q15
    wf1 -- array of type Word16 -- 1st LSF weighting factors,   Q13
    wf2 -- array of type Word16 -- 2nd LSF weighting factors,   Q13
    dico_size -- Word16 -- size of quantization codebook,       Q0
 Outputs:
    pOverflow -- pointer to type Flag -- overflow indicator

 Returns:
    Word16 -- quantization index, Q0

 Global Variables Used:
    None

 Local Variables Needed:
    None

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

 This function performs the quantization of a 4-dimensional subvector.

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

 None

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

 q_plsf_5.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]

------------------------------------------------------------------------------
*/
/* Quantization of a 4 dimensional subvector */

static Word16 Vq_subvec( /* o : quantization index,            Q0  */
    Word16 *lsf_r1,      /* i : 1st LSF residual vector,       Q15 */
    Word16 *lsf_r2,      /* i : 2nd LSF residual vector,       Q15 */
    const Word16 *dico,  /* i : quantization codebook,         Q15 */
    Word16 *wf1,         /* i : 1st LSF weighting factors      Q13 */
    Word16 *wf2,         /* i : 2nd LSF weighting factors      Q13 */
    Word16 dico_size,    /* i : size of quantization codebook, Q0  */
    Flag   *pOverflow    /* o : overflow indicator                 */
)
{
    Word16 index = 0; /* initialization only needed to keep gcc silent */
    Word16 i;
    Word16 temp;
    const Word16 *p_dico;
    Word32 dist_min;
    Word32 dist;
    Word16 wf1_0;
    Word16 wf1_1;
    Word16 wf2_0;
    Word16 wf2_1;
    Word32 aux1;
    Word32 aux2;
    Word32 aux3;
    Word32 aux4;

    OSCL_UNUSED_ARG(pOverflow);

    dist_min = MAX_32;
    p_dico = dico;

    wf1_0 = wf1[0];
    wf1_1 = wf1[1];
    wf2_0 = wf2[0];
    wf2_1 = wf2[1];

    aux1 = ((Word32) lsf_r1[0] * wf1_0);
    aux2 = ((Word32) lsf_r1[1] * wf1_1);
    aux3 = ((Word32) lsf_r2[0] * wf2_0);
    aux4 = ((Word32) lsf_r2[1] * wf2_1);

    for (i = 0; i < dico_size; i++)
    {
        temp  = (aux1 - ((Word32)wf1_0 * *(p_dico++))) >> 15;
        dist  = ((Word32)temp * temp);

        if (dist >= dist_min)
        {
            p_dico += 3;
            continue;
        }

        temp  = (aux2 - ((Word32)wf1_1 * *(p_dico++))) >> 15;
        dist += ((Word32)temp * temp);

        if (dist >= dist_min)
        {
            p_dico += 2;
            continue;
        }

        temp  = (aux3 - ((Word32)wf2_0 * *(p_dico++))) >> 15;
        dist += ((Word32)temp * temp);

        if (dist >= dist_min)
        {
            p_dico += 1;
            continue;
        }

        temp  = (aux4 - ((Word32)wf2_1 * *(p_dico++))) >> 15;
        dist += ((Word32)temp * temp);


        if (dist < dist_min)
        {
            dist_min = dist;
            index = i;
        }
    }



    /* Reading the selected vector */

    p_dico = &dico[ index<<2];
    lsf_r1[0] = *p_dico++;
    lsf_r1[1] = *p_dico++;
    lsf_r2[0] = *p_dico++;
    lsf_r2[1] = *p_dico++;

    return index;

}


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

 Inputs:
    lsf_r1 -- array of type Word16 -- 1st LSF residual vector,  Q15
    lsf_r2 -- array of type Word16 -- 2nd LSF residual vector,  Q15
    dico -- pointer to const Word16 -- quantization codebook,   Q15
    wf1 -- array of type Word16 -- 1st LSF weighting factors,   Q13
    wf2 -- array of type Word16 -- 2nd LSF weighting factors,   Q13
    dico_size -- Word16 -- size of quantization codebook,       Q0

 Outputs:
    pOverflow -- pointer to type Flag -- overflow indicator

 Returns:
    Word16 -- quantization index, Q0

 Global Variables Used:
    None

 Local Variables Needed:
    None

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

 This function performs the quantization of a 4-dimensional subvector.

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

 None

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

 q_plsf_5.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001

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