FreeCalypso > hg > gsm-codec-lib
view libtwamr/ph_disp.c @ 452:6e595f7d40e2
CHANGES: document changes for the upcoming release
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Fri, 10 May 2024 03:45:47 +0000 |
parents | bde9f5804670 |
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/* ******************************************************************************** * * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001 * R99 Version 3.3.0 * REL-4 Version 4.1.0 * ******************************************************************************** * * File : ph_disp.c * Purpose : Perform adaptive phase dispersion of the excitation * signal. * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #include "namespace.h" #include "ph_disp.h" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #include "basic_op.h" #include "no_count.h" #include "cnst.h" #include "memops.h" /* ******************************************************************************** * LOCAL VARIABLES AND TABLES ******************************************************************************** */ #include "ph_disp.tab" /* ******************************************************************************** * PUBLIC PROGRAM CODE ******************************************************************************** */ /************************************************************************* * * Function: ph_disp_reset * ************************************************************************** */ void ph_disp_reset (ph_dispState *state) { Word16 i; for (i=0; i<PHDGAINMEMSIZE; i++) { state->gainMem[i] = 0; } state->prevState = 0; state->prevCbGain = 0; state->lockFull = 0; state->onset = 0; /* assume no onset in start */ } /************************************************************************* * * Function: ph_disp_lock * ************************************************************************** */ void ph_disp_lock (ph_dispState *state) { state->lockFull = 1; return; } /************************************************************************* * * Function: ph_disp_release * ************************************************************************** */ void ph_disp_release (ph_dispState *state) { state->lockFull = 0; return; } /************************************************************************* * * Function: ph_disp * * Adaptive phase dispersion; forming of total excitation * (for synthesis part of decoder) * ************************************************************************** */ void ph_disp ( ph_dispState *state, /* i/o : State struct */ enum Mode mode, /* i : codec mode */ Word16 x[], /* i/o Q0 : in: LTP excitation signal */ /* out: total excitation signal */ Word16 cbGain, /* i Q1 : Codebook gain */ Word16 ltpGain, /* i Q14 : LTP gain */ Word16 inno[], /* i/o Q13 : Innovation vector (Q12 for 12.2) */ Word16 pitch_fac, /* i Q14 : pitch factor used to scale the LTP excitation (Q13 for 12.2) */ Word16 tmp_shift /* i Q0 : shift factor applied to sum of scaled LTP ex & innov. before rounding */ ) { Word16 i, i1; Word16 tmp1; Word32 L_temp; Word16 impNr; /* indicator for amount of disp./filter used */ Word16 inno_sav[L_SUBFR]; Word16 ps_poss[L_SUBFR]; Word16 j, nze, nPulse, ppos; const Word16 *ph_imp; /* Pointer to phase dispersion filter */ /* Update LTP gain memory */ for (i = PHDGAINMEMSIZE-1; i > 0; i--) { state->gainMem[i] = state->gainMem[i-1]; move16 (); } state->gainMem[0] = ltpGain; move16 (); /* basic adaption of phase dispersion */ test (); if (sub(ltpGain, PHDTHR2LTP) < 0) { /* if (ltpGain < 0.9) */ test (); if (sub(ltpGain, PHDTHR1LTP) > 0) { /* if (ltpGain > 0.6 */ impNr = 1; /* medium dispersion */ move16 (); } else { impNr = 0; /* maximum dispersion */ move16 (); } } else { impNr = 2; /* no dispersion */ move16 (); } /* onset indicator */ /* onset = (cbGain > onFact * cbGainMem[0]) */ move32 (); tmp1 = round(L_shl(L_mult(state->prevCbGain, ONFACTPLUS1), 2)); test (); if (sub(cbGain, tmp1) > 0) { state->onset = ONLENGTH; move16 (); } else { test (); if (state->onset > 0) { state->onset = sub (state->onset, 1); move16 (); } } /* if not onset, check ltpGain buffer and use max phase dispersion if half or more of the ltpGain-parameters say so */ test (); if (state->onset == 0) { /* Check LTP gain memory and set filter accordingly */ i1 = 0; move16 (); for (i = 0; i < PHDGAINMEMSIZE; i++) { test (); if (sub(state->gainMem[i], PHDTHR1LTP) < 0) { i1 = add (i1, 1); } } test (); if (sub(i1, 2) > 0) { impNr = 0; move16 (); } } /* Restrict decrease in phase dispersion to one step if not onset */ test (); test (); if ((sub(impNr, add(state->prevState, 1)) > 0) && (state->onset == 0)) { impNr = sub (impNr, 1); } /* if onset, use one step less phase dispersion */ test (); test (); if((sub(impNr, 2) < 0) && (state->onset > 0)) { impNr = add (impNr, 1); } /* disable for very low levels */ test (); if(sub(cbGain, 10) < 0) { impNr = 2; move16 (); } test (); if(sub(state->lockFull, 1) == 0) { impNr = 0; move16 (); } /* update static memory */ state->prevState = impNr; move16 (); state->prevCbGain = cbGain; move16 (); /* do phase dispersion for all modes but 12.2 and 7.4; don't modify the innovation if impNr >=2 (= no phase disp) */ test (); test (); test(); test(); if (sub(mode, MR122) != 0 && sub(mode, MR102) != 0 && sub(mode, MR74) != 0 && sub(impNr, 2) < 0) { /* track pulse positions, save innovation, and initialize new innovation */ nze = 0; move16 (); for (i = 0; i < L_SUBFR; i++) { move16 (); test(); if (inno[i] != 0) { ps_poss[nze] = i; move16 (); nze = add (nze, 1); } inno_sav[i] = inno[i]; move16 (); inno[i] = 0; move16 (); } /* Choose filter corresponding to codec mode and dispersion criterium */ test (); if (sub (mode, MR795) == 0) { test (); if (impNr == 0) { ph_imp = ph_imp_low_MR795; move16 (); } else { ph_imp = ph_imp_mid_MR795; move16 (); } } else { test (); if (impNr == 0) { ph_imp = ph_imp_low; move16 (); } else { ph_imp = ph_imp_mid; move16 (); } } /* Do phase dispersion of innovation */ for (nPulse = 0; nPulse < nze; nPulse++) { ppos = ps_poss[nPulse]; move16 (); /* circular convolution with impulse response */ j = 0; move16 (); for (i = ppos; i < L_SUBFR; i++) { /* inno[i1] += inno_sav[ppos] * ph_imp[i1-ppos] */ tmp1 = mult(inno_sav[ppos], ph_imp[j++]); inno[i] = add(inno[i], tmp1); move16 (); } for (i = 0; i < ppos; i++) { /* inno[i] += inno_sav[ppos] * ph_imp[L_SUBFR-ppos+i] */ tmp1 = mult(inno_sav[ppos], ph_imp[j++]); inno[i] = add(inno[i], tmp1); move16 (); } } } /* compute total excitation for synthesis part of decoder (using modified innovation if phase dispersion is active) */ for (i = 0; i < L_SUBFR; i++) { /* x[i] = gain_pit*x[i] + cbGain*code[i]; */ L_temp = L_mult ( x[i], pitch_fac); /* 12.2: Q0 * Q13 */ /* 7.4: Q0 * Q14 */ L_temp = L_mac (L_temp, inno[i], cbGain); /* 12.2: Q12 * Q1 */ /* 7.4: Q13 * Q1 */ L_temp = L_shl (L_temp, tmp_shift); /* Q16 */ x[i] = round (L_temp); move16 (); } return; }