view libgsmefr/q_plsf_5.c @ 183:452c1d5a6268

libgsmefr BFI w/o data: emit zero output after decoder reset In real-life usage, each EFR decoder session will most likely begin with lots of BFI frames before the first real frame arrives. However, because the spec-defined home state of the decoder is speech rather than CN, our regular logic for BFI w/o data would have to feed pseudorandom noise to the decoder (in the "fixed codebook excitation pulses" part), which is silly to do at the beginning of the decoder session right out of reset. Therefore, let's check reset_flag_old, and if we are still in the reset state, simply emit zero output.
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 03 Jan 2023 00:12:18 +0000
parents cc08498ed21b
children 72cf52ba91f8
line wrap: on
line source

/*************************************************************************
 *   FUNCTION:  Q_plsf_5()
 *
 *   PURPOSE:  Quantization of 2 sets of LSF parameters using 1st order MA
 *             prediction and split by 5 matrix quantization (split-MQ)
 *
 *   DESCRIPTION:
 *
 *        p[i] = pred_factor*past_r2q[i];   i=0,...,m-1
 *        r1[i]= lsf1[i] - p[i];      i=0,...,m-1
 *        r2[i]= lsf2[i] - p[i];      i=0,...,m-1
 *   where:
 *        lsf1[i]           1st mean-removed LSF vector.
 *        lsf2[i]           2nd mean-removed LSF vector.
 *        r1[i]             1st residual prediction vector.
 *        r2[i]             2nd residual prediction vector.
 *        past_r2q[i]       Past quantized residual (2nd vector).
 *
 *   The residual vectors r1[i] and r2[i] are jointly quantized using
 *   split-MQ with 5 codebooks. Each 4th dimension submatrix contains 2
 *   elements from each residual vector. The 5 submatrices are as follows:
 *     {r1[0], r1[1], r2[0], r2[1]};  {r1[2], r1[3], r2[2], r2[3]};
 *     {r1[4], r1[5], r2[4], r2[5]};  {r1[6], r1[7], r2[6], r2[7]};
 *                    {r1[8], r1[9], r2[8], r2[9]};
 *
 *************************************************************************/

#include "gsm_efr.h"
#include "typedef.h"
#include "namespace.h"
#include "basic_op.h"
#include "no_count.h"
#include "sig_proc.h"
#include "codec.h"

#include "cnst.h"
#include "dtx.h"
#include "enc_state.h"

#include "q_plsf5_tab.h"         /* Codebooks of LSF prediction residual */

/* Locals functions */

static void Lsf_wt (
    Word16 *lsf,       /* input : LSF vector                    */
     Word16 *wf2       /* output: square of weighting factors   */
);

static
Word16 Vq_subvec (     /* output: return quantization index     */
    Word16 *lsf_r1,    /* input : 1st LSF residual vector       */
    Word16 *lsf_r2,    /* input : and LSF residual vector       */
    const Word16 *dico,/* input : quantization codebook         */
    Word16 *wf1,       /* input : 1st LSF weighting factors     */
    Word16 *wf2,       /* input : 2nd LSF weighting factors     */
    Word16 dico_size   /* input : size of quantization codebook */
);

static
Word16 Vq_subvec_s (   /* output: return quantization index     */
    Word16 *lsf_r1,    /* input : 1st LSF residual vector       */
    Word16 *lsf_r2,    /* input : and LSF residual vector       */
    const Word16 *dico,/* input : quantization codebook         */
    Word16 *wf1,       /* input : 1st LSF weighting factors     */
    Word16 *wf2,       /* input : 2nd LSF weighting factors     */
    Word16 dico_size   /* input : size of quantization codebook */
);

/* M  ->order of linear prediction filter                      */
/* LSF_GAP  -> Minimum distance between LSF after quantization */
/*             50 Hz = 205                                     */
/* PRED_FAC -> Predcition factor                               */

#define M         10
#define LSF_GAP   205
#define PRED_FAC  21299

void Q_plsf_5 (
    struct EFR_encoder_state *st,
    Word16 *lsp1,      /* input : 1st LSP vector                     */
    Word16 *lsp2,      /* input : 2nd LSP vector                     */
    Word16 *lsp1_q,    /* output: quantized 1st LSP vector           */
    Word16 *lsp2_q,    /* output: quantized 2nd LSP vector           */
    Word16 *indice,    /* output: quantization indices of 5 matrices */
    Word16 txdtx_ctrl  /* input : tx dtx control word                */
)
{
    Word16 i;
    Word16 lsf1[M], lsf2[M], wf1[M], wf2[M], lsf_p[M], lsf_r1[M], lsf_r2[M];
    Word16 lsf1_q[M], lsf2_q[M];
    Word16 lsf_aver[M];

    /* convert LSFs to normalize frequency domain 0..16384  */

    Lsp_lsf (lsp1, lsf1, M);
    Lsp_lsf (lsp2, lsf2, M);

    /* Update LSF CN quantizer "memory" */

    if ((txdtx_ctrl & TX_SP_FLAG) == 0
        && (txdtx_ctrl & TX_PREV_HANGOVER_ACTIVE) != 0)
    {
        update_lsf_p_CN (st->lsf_old_tx, st->lsf_p_CN);
    }
    if ((txdtx_ctrl & TX_SID_UPDATE) != 0)
    {
        /* New SID frame is to be sent:
        Compute average of the current LSFs and the LSFs in the history */

        aver_lsf_history (st->lsf_old_tx, lsf1, lsf2, lsf_aver);
    }
    /* Update LSF history with unquantized LSFs when no speech activity
    is present */

    if ((txdtx_ctrl & TX_SP_FLAG) == 0)
    {
        update_lsf_history (lsf1, lsf2, st->lsf_old_tx);
    }
    if ((txdtx_ctrl & TX_SID_UPDATE) != 0)
    {
        /* Compute LSF weighting factors for lsf2, using averaged LSFs */
        /* Set LSF weighting factors for lsf1 to zero */
        /* Replace lsf1 and lsf2 by the averaged LSFs */

        Lsf_wt (lsf_aver, wf2);
        for (i = 0; i < M; i++)
        {
            wf1[i] = 0;                                 move16 (); 
            lsf1[i] = lsf_aver[i];                      move16 (); 
            lsf2[i] = lsf_aver[i];                      move16 (); 
        }
    }
    else
    {
        /* Compute LSF weighting factors */

        Lsf_wt (lsf1, wf1);
        Lsf_wt (lsf2, wf2);
    }

    /* Compute predicted LSF and prediction error */

    if ((txdtx_ctrl & TX_SP_FLAG) != 0)
    {
        for (i = 0; i < M; i++)
        {
            lsf_p[i] = add (mean_lsf[i], mult (st->past_r2_q[i], PRED_FAC));
            lsf_r1[i] = sub (lsf1[i], lsf_p[i]);
            lsf_r2[i] = sub (lsf2[i], lsf_p[i]);
        }
    }
    else
    {
        for (i = 0; i < M; i++)
        {
            lsf_r1[i] = sub (lsf1[i], st->lsf_p_CN[i]);
            lsf_r2[i] = sub (lsf2[i], st->lsf_p_CN[i]);
        }
    }

    /*---- Split-VQ of prediction error ----*/

    indice[0] = Vq_subvec (&lsf_r1[0], &lsf_r2[0], dico1_lsf,
                           &wf1[0], &wf2[0], DICO1_SIZE);
                                                        move16 (); 

    indice[1] = Vq_subvec (&lsf_r1[2], &lsf_r2[2], dico2_lsf,
                           &wf1[2], &wf2[2], DICO2_SIZE);
                                                        move16 (); 

    indice[2] = Vq_subvec_s (&lsf_r1[4], &lsf_r2[4], dico3_lsf,
                             &wf1[4], &wf2[4], DICO3_SIZE);
                                                        move16 (); 

    indice[3] = Vq_subvec (&lsf_r1[6], &lsf_r2[6], dico4_lsf,
                           &wf1[6], &wf2[6], DICO4_SIZE);
                                                        move16 (); 

    indice[4] = Vq_subvec (&lsf_r1[8], &lsf_r2[8], dico5_lsf,
                           &wf1[8], &wf2[8], DICO5_SIZE);
                                                        move16 (); 

    /* Compute quantized LSFs and update the past quantized residual */
    /* In case of no speech activity, skip computing the quantized LSFs,
       and set past_r2_q to zero (initial value) */

    if ((txdtx_ctrl & TX_SP_FLAG) != 0)
    {
        for (i = 0; i < M; i++)
        {
            lsf1_q[i] = add (lsf_r1[i], lsf_p[i]);
            lsf2_q[i] = add (lsf_r2[i], lsf_p[i]);
            st->past_r2_q[i] = lsf_r2[i];
        }

        /* verification that LSFs has minimum distance of LSF_GAP */

        Reorder_lsf (lsf1_q, LSF_GAP, M);
        Reorder_lsf (lsf2_q, LSF_GAP, M);

        /* Update LSF history with quantized LSFs
        when hangover period is active */

        if ((txdtx_ctrl & TX_HANGOVER_ACTIVE) != 0)
        {
            update_lsf_history (lsf1_q, lsf2_q, st->lsf_old_tx);
        }
        /*  convert LSFs to the cosine domain */

        Lsf_lsp (lsf1_q, lsp1_q, M);
        Lsf_lsp (lsf2_q, lsp2_q, M);
    }
    else
    {
        for (i = 0; i < M; i++)
        {
            st->past_r2_q[i] = 0;
        }
    }

    return;
}

/* Quantization of a 4 dimensional subvector */

static
Word16 Vq_subvec (      /* output: return quantization index     */
    Word16 *lsf_r1,     /* input : 1st LSF residual vector       */
    Word16 *lsf_r2,     /* input : and LSF residual vector       */
    const Word16 *dico, /* input : quantization codebook         */
    Word16 *wf1,        /* input : 1st LSF weighting factors     */
    Word16 *wf2,        /* input : 2nd LSF weighting factors     */
    Word16 dico_size    /* input : size of quantization codebook */
)
{
    Word16 i, index, temp;
    const Word16 *p_dico;
    Word32 dist_min, dist;

    dist_min = MAX_32;                                  move32 (); 
    p_dico = dico;                                      move16 (); 

    for (i = 0; i < dico_size; i++)
    {
        temp = sub (lsf_r1[0], *p_dico++);
        temp = mult (wf1[0], temp);
        dist = L_mult (temp, temp);

        temp = sub (lsf_r1[1], *p_dico++);
        temp = mult (wf1[1], temp);
        dist = L_mac (dist, temp, temp);

        temp = sub (lsf_r2[0], *p_dico++);
        temp = mult (wf2[0], temp);
        dist = L_mac (dist, temp, temp);

        temp = sub (lsf_r2[1], *p_dico++);
        temp = mult (wf2[1], temp);
        dist = L_mac (dist, temp, temp);

        test (); 
        if (L_sub (dist, dist_min) < (Word32) 0)
        {
            dist_min = dist;                            move32 (); 
            index = i;                                  move16 (); 
        }
    }

    /* Reading the selected vector */

    p_dico = &dico[shl (index, 2)];                     move16 (); 
    lsf_r1[0] = *p_dico++;                              move16 (); 
    lsf_r1[1] = *p_dico++;                              move16 (); 
    lsf_r2[0] = *p_dico++;                              move16 (); 
    lsf_r2[1] = *p_dico++;                              move16 (); 

    return index;

}

/* Quantization of a 4 dimensional subvector with a signed codebook */

static
Word16 Vq_subvec_s (    /* output: return quantization index     */
    Word16 *lsf_r1,     /* input : 1st LSF residual vector       */
    Word16 *lsf_r2,     /* input : and LSF residual vector       */
    const Word16 *dico, /* input : quantization codebook         */
    Word16 *wf1,        /* input : 1st LSF weighting factors     */
    Word16 *wf2,        /* input : 2nd LSF weighting factors     */
    Word16 dico_size)   /* input : size of quantization codebook */
{
    Word16 i, index, sign, temp;
    const Word16 *p_dico;
    Word32 dist_min, dist;

    dist_min = MAX_32;                                  move32 (); 
    p_dico = dico;                                      move16 (); 

    for (i = 0; i < dico_size; i++)
    {
        /* test positive */

        temp = sub (lsf_r1[0], *p_dico++);
        temp = mult (wf1[0], temp);
        dist = L_mult (temp, temp);

        temp = sub (lsf_r1[1], *p_dico++);
        temp = mult (wf1[1], temp);
        dist = L_mac (dist, temp, temp);

        temp = sub (lsf_r2[0], *p_dico++);
        temp = mult (wf2[0], temp);
        dist = L_mac (dist, temp, temp);

        temp = sub (lsf_r2[1], *p_dico++);
        temp = mult (wf2[1], temp);
        dist = L_mac (dist, temp, temp);

        test (); 
        if (L_sub (dist, dist_min) < (Word32) 0)
        {
            dist_min = dist;                            move32 (); 
            index = i;                                  move16 (); 
            sign = 0;                                   move16 (); 
        }
        /* test negative */

        p_dico -= 4;                                    move16 (); 
        temp = add (lsf_r1[0], *p_dico++);
        temp = mult (wf1[0], temp);
        dist = L_mult (temp, temp);

        temp = add (lsf_r1[1], *p_dico++);
        temp = mult (wf1[1], temp);
        dist = L_mac (dist, temp, temp);

        temp = add (lsf_r2[0], *p_dico++);
        temp = mult (wf2[0], temp);
        dist = L_mac (dist, temp, temp);

        temp = add (lsf_r2[1], *p_dico++);
        temp = mult (wf2[1], temp);
        dist = L_mac (dist, temp, temp);

        test (); 
        if (L_sub (dist, dist_min) < (Word32) 0)
        {
            dist_min = dist;                            move32 (); 
            index = i;                                  move16 (); 
            sign = 1;                                   move16 (); 
        }
    }

    /* Reading the selected vector */

    p_dico = &dico[shl (index, 2)];                     move16 (); 
    test (); 
    if (sign == 0)
    {
        lsf_r1[0] = *p_dico++;                          move16 (); 
        lsf_r1[1] = *p_dico++;                          move16 (); 
        lsf_r2[0] = *p_dico++;                          move16 (); 
        lsf_r2[1] = *p_dico++;                          move16 (); 
    }
    else
    {
        lsf_r1[0] = negate (*p_dico++);                 move16 (); 
        lsf_r1[1] = negate (*p_dico++);                 move16 (); 
        lsf_r2[0] = negate (*p_dico++);                 move16 (); 
        lsf_r2[1] = negate (*p_dico++);                 move16 (); 
    }

    index = shl (index, 1);
    index = add (index, sign);

    return index;

}

/****************************************************
 * FUNCTION  Lsf_wt                                                         *
 *                                                                          *
 ****************************************************
 * Compute LSF weighting factors                                            *
 *                                                                          *
 *  d[i] = lsf[i+1] - lsf[i-1]                                              *
 *                                                                          *
 *  The weighting factors are approximated by two line segment.             *
 *                                                                          *
 *  First segment passes by the following 2 points:                         *
 *                                                                          *
 *     d[i] = 0Hz     wf[i] = 3.347                                         *
 *     d[i] = 450Hz   wf[i] = 1.8                                           *
 *                                                                          *
 *  Second segment passes by the following 2 points:                        *
 *                                                                          *
 *     d[i] = 450Hz   wf[i] = 1.8                                           *
 *     d[i] = 1500Hz  wf[i] = 1.0                                           *
 *                                                                          *
 *  if( d[i] < 450Hz )                                                      *
 *    wf[i] = 3.347 - ( (3.347-1.8) / (450-0)) *  d[i]                      *
 *  else                                                                    *
 *    wf[i] = 1.8 - ( (1.8-1.0) / (1500-450)) *  (d[i] - 450)               *
 *                                                                          *
 *                                                                          *
 *  if( d[i] < 1843)                                                        *
 *    wf[i] = 3427 - (28160*d[i])>>15                                       *
 *  else                                                                    *
 *    wf[i] = 1843 - (6242*(d[i]-1843))>>15                                 *
 *                                                                          *
 *--------------------------------------------------------------------------*/

static
void Lsf_wt (
    Word16 *lsf,         /* input : LSF vector                  */
    Word16 *wf)          /* output: square of weighting factors */
{
    Word16 temp;
    Word16 i;
    /* wf[0] = lsf[1] - 0  */
    wf[0] = lsf[1];                                     move16 (); 
    for (i = 1; i < 9; i++)
    {
        wf[i] = sub (lsf[i + 1], lsf[i - 1]);           move16 (); 
    }
    /* wf[9] = 0.5 - lsf[8] */    
    wf[9] = sub (16384, lsf[8]);move16 ();      

    for (i = 0; i < 10; i++)
    {
        temp = sub (wf[i], 1843);
        test (); 
        if (temp < 0)
        {
            wf[i] = sub (3427, mult (wf[i], 28160));    move16 (); 
        }
        else
        {
            wf[i] = sub (1843, mult (temp, 6242));      move16 (); 
        }

        wf[i] = shl (wf[i], 3); move16 (); 
    }
    return;
}