FreeCalypso > hg > gsm-codec-lib
view libgsmefr/d_gains.c @ 58:d285877fc4cc
libgsmefr: cod_12k2.c compiles
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Fri, 25 Nov 2022 18:50:50 +0000 |
parents | 49dd1ac8e75b |
children | a18782a7d270 |
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/************************************************************************* * * FILE NAME: D_GAINS.C * * FUNCTIONS DEFINED IN THIS FILE: * * d_gain_pitch(), d_gain_code() and gmed5() * * MA prediction is performed on the innovation energy * ( in dB/(20*log10(2)) ) with mean removed. *************************************************************************/ #include "typedef.h" #include "basic_op.h" #include "oper_32b.h" #include "count.h" #include "sig_proc.h" #include "gains_tb.h" #include "cnst.h" #include "dtx.h" extern Word16 gain_code_old_rx[4 * DTX_HANGOVER]; /* Static variables for bad frame handling */ /* Variables used by d_gain_pitch: */ Word16 pbuf[5], past_gain_pit, prev_gp; /* Variables used by d_gain_code: */ Word16 gbuf[5], past_gain_code, prev_gc; /* Static variables for CNI (used by d_gain_code) */ Word16 gcode0_CN, gain_code_old_CN, gain_code_new_CN, gain_code_muting_CN; /* Memories of gain dequantization: */ /* past quantized energies. */ /* initialized to -14.0/constant, constant = 20*Log10(2) */ Word16 past_qua_en[4]; /* MA prediction coeff */ Word16 pred[4]; /************************************************************************* * * FUNCTION: gmed5 * * PURPOSE: calculates 5-point median. * * DESCRIPTION: * *************************************************************************/ Word16 gmed5 ( /* out : index of the median value (0...4) */ Word16 ind[] /* in : Past gain values */ ) { Word16 i, j, ix = 0, tmp[5]; Word16 max, tmp2[5]; for (i = 0; i < 5; i++) { tmp2[i] = ind[i]; move16 (); } for (i = 0; i < 5; i++) { max = -8192; move16 (); for (j = 0; j < 5; j++) { test (); if (sub (tmp2[j], max) >= 0) { max = tmp2[j]; move16 (); ix = j; move16 (); } } tmp2[ix] = -16384; move16 (); tmp[i] = ix; move16 (); } return (ind[tmp[2]]); } /************************************************************************* * * FUNCTION: d_gain_pitch * * PURPOSE: decodes the pitch gain using the received index. * * DESCRIPTION: * In case of no frame erasure, the gain is obtained from the * quantization table at the given index; otherwise, a downscaled * past gain is used. * *************************************************************************/ Word16 d_gain_pitch ( /* out : quantized pitch gain */ Word16 index, /* in : index of quantization */ Word16 bfi, /* in : bad frame indicator (good = 0) */ Word16 state, Word16 prev_bf, Word16 rxdtx_ctrl ) { static const Word16 pdown[7] = { 32767, 32112, 32112, 26214, 9830, 6553, 6553 }; Word16 gain, tmp, i; test (); if (bfi == 0) { test (); logic16 (); if ((rxdtx_ctrl & RX_SP_FLAG) != 0) { gain = shr (qua_gain_pitch[index], 2); move16 (); test (); if (prev_bf != 0) { test (); if (sub (gain, prev_gp) > 0) { gain = prev_gp; } } } else { gain = 0; move16 (); } prev_gp = gain; move16 (); } else { test (); logic16 (); if ((rxdtx_ctrl & RX_SP_FLAG) != 0) { tmp = gmed5 (pbuf); move16 (); test (); if (sub (tmp, past_gain_pit) < 0) { past_gain_pit = tmp; move16 (); } gain = mult (pdown[state], past_gain_pit); } else { gain = 0; move16 (); } } past_gain_pit = gain; move16 (); test (); if (sub (past_gain_pit, 4096) > 0) /* if (past_gain_pit > 1.0) */ { past_gain_pit = 4096; move16 (); } for (i = 1; i < 5; i++) { pbuf[i - 1] = pbuf[i]; move16 (); } pbuf[4] = past_gain_pit; move16 (); return gain; } /************************************************************************* * * FUNCTION: d_gain_code * * PURPOSE: decode the fixed codebook gain using the received index. * * DESCRIPTION: * The received index gives the gain correction factor gamma. * The quantized gain is given by g_q = g0 * gamma * where g0 is the predicted gain. * To find g0, 4th order MA prediction is applied to the mean-removed * innovation energy in dB. * In case of frame erasure, downscaled past gain is used. * *************************************************************************/ /* average innovation energy. */ /* MEAN_ENER = 36.0/constant, constant = 20*Log10(2) */ #define MEAN_ENER 783741L /* 36/(20*log10(2)) */ void d_gain_code ( Word16 index, /* input : received quantization index */ Word16 code[], /* input : innovation codevector */ Word16 lcode, /* input : codevector length */ Word16 *gain_code, /* output: decoded innovation gain */ Word16 bfi, /* input : bad frame indicator */ Word16 state, Word16 prev_bf, Word16 rxdtx_ctrl, Word16 i_subfr, Word16 rx_dtx_state ) { static const Word16 cdown[7] = { 32767, 32112, 32112, 32112, 32112, 32112, 22937 }; Word16 i, tmp; Word16 gcode0, exp, frac, av_pred_en; Word32 ener, ener_code; test (); test (); logic16 (); if (((rxdtx_ctrl & RX_UPD_SID_QUANT_MEM) != 0) && (i_subfr == 0)) { gcode0_CN = update_gcode0_CN (gain_code_old_rx); move16 (); gcode0_CN = shl (gcode0_CN, 4); } /* Handle cases of comfort noise fixed codebook gain decoding in which past valid SID frames are repeated */ test (); test (); test (); logic16 (); logic16 (); logic16 (); if (((rxdtx_ctrl & RX_NO_TRANSMISSION) != 0) || ((rxdtx_ctrl & RX_INVALID_SID_FRAME) != 0) || ((rxdtx_ctrl & RX_LOST_SID_FRAME) != 0)) { test (); logic16 (); if ((rxdtx_ctrl & RX_NO_TRANSMISSION) != 0) { /* DTX active: no transmission. Interpolate gain values in memory */ test (); if (i_subfr == 0) { *gain_code = interpolate_CN_param (gain_code_old_CN, gain_code_new_CN, rx_dtx_state); move16 (); } else { *gain_code = prev_gc; move16 (); } } else { /* Invalid or lost SID frame: use gain values from last good SID frame */ gain_code_old_CN = gain_code_new_CN; move16 (); *gain_code = gain_code_new_CN; move16 (); /* reset table of past quantized energies */ for (i = 0; i < 4; i++) { past_qua_en[i] = -2381; move16 (); } } test (); logic16 (); if ((rxdtx_ctrl & RX_DTX_MUTING) != 0) { /* attenuate the gain value by 0.75 dB in each subframe */ /* (total of 3 dB per frame) */ gain_code_muting_CN = mult (gain_code_muting_CN, 30057); *gain_code = gain_code_muting_CN; move16 (); } else { /* Prepare for DTX muting by storing last good gain value */ gain_code_muting_CN = gain_code_new_CN; move16 (); } past_gain_code = *gain_code; move16 (); for (i = 1; i < 5; i++) { gbuf[i - 1] = gbuf[i]; move16 (); } gbuf[4] = past_gain_code; move16 (); prev_gc = past_gain_code; move16 (); return; } /*----------------- Test erasure ---------------*/ test (); if (bfi != 0) { tmp = gmed5 (gbuf); move16 (); test (); if (sub (tmp, past_gain_code) < 0) { past_gain_code = tmp; move16 (); } past_gain_code = mult (past_gain_code, cdown[state]); *gain_code = past_gain_code; move16 (); av_pred_en = 0; move16 (); for (i = 0; i < 4; i++) { av_pred_en = add (av_pred_en, past_qua_en[i]); } /* av_pred_en = 0.25*av_pred_en - 4/(20Log10(2)) */ av_pred_en = mult (av_pred_en, 8192); /* *= 0.25 */ /* if (av_pred_en < -14/(20Log10(2))) av_pred_en = .. */ test (); if (sub (av_pred_en, -2381) < 0) { av_pred_en = -2381; move16 (); } for (i = 3; i > 0; i--) { past_qua_en[i] = past_qua_en[i - 1]; move16 (); } past_qua_en[0] = av_pred_en; move16 (); for (i = 1; i < 5; i++) { gbuf[i - 1] = gbuf[i]; move16 (); } gbuf[4] = past_gain_code; move16 (); /* Use the most recent comfort noise fixed codebook gain value for updating the fixed codebook gain history */ test (); if (gain_code_new_CN == 0) { tmp = prev_gc; move16 (); } else { tmp = gain_code_new_CN; } update_gain_code_history_rx (tmp, gain_code_old_rx); test (); if (sub (i_subfr, (3 * L_SUBFR)) == 0) { gain_code_old_CN = *gain_code; move16 (); } return; } test (); logic16 (); if ((rxdtx_ctrl & RX_SP_FLAG) != 0) { /*-------------- Decode codebook gain ---------------*/ /*-------------------------------------------------------------------* * energy of code: * * ~~~~~~~~~~~~~~~ * * ener_code = 10 * Log10(energy/lcode) / constant * * = 1/2 * Log2(energy/lcode) * * constant = 20*Log10(2) * *-------------------------------------------------------------------*/ /* ener_code = log10(ener_code/lcode) / (20*log10(2)) */ ener_code = 0; move32 (); for (i = 0; i < lcode; i++) { ener_code = L_mac (ener_code, code[i], code[i]); } /* ener_code = ener_code / lcode */ ener_code = L_mult (round (ener_code), 26214); /* ener_code = 1/2 * Log2(ener_code) */ Log2 (ener_code, &exp, &frac); ener_code = L_Comp (sub (exp, 30), frac); /* predicted energy */ ener = MEAN_ENER; move32 (); for (i = 0; i < 4; i++) { ener = L_mac (ener, past_qua_en[i], pred[i]); } /*-------------------------------------------------------------------* * predicted codebook gain * * ~~~~~~~~~~~~~~~~~~~~~~~ * * gcode0 = Pow10( (ener*constant - ener_code*constant) / 20 ) * * = Pow2(ener-ener_code) * * constant = 20*Log10(2) * *-------------------------------------------------------------------*/ ener = L_shr (L_sub (ener, ener_code), 1); L_Extract (ener, &exp, &frac); gcode0 = extract_l (Pow2 (exp, frac)); /* predicted gain */ gcode0 = shl (gcode0, 4); *gain_code = mult (qua_gain_code[index], gcode0); move16 (); test (); if (prev_bf != 0) { test (); if (sub (*gain_code, prev_gc) > 0) { *gain_code = prev_gc; move16 (); } } /*-------------------------------------------------------------------* * update table of past quantized energies * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * past_qua_en = 20 * Log10(qua_gain_code) / constant * * = Log2(qua_gain_code) * * constant = 20*Log10(2) * *-------------------------------------------------------------------*/ for (i = 3; i > 0; i--) { past_qua_en[i] = past_qua_en[i - 1]; move16 (); } Log2 (L_deposit_l (qua_gain_code[index]), &exp, &frac); past_qua_en[0] = shr (frac, 5); move16 (); past_qua_en[0] = add (past_qua_en[0], shl (sub (exp, 11), 10)); move16 (); update_gain_code_history_rx (*gain_code, gain_code_old_rx); if (sub (i_subfr, (3 * L_SUBFR)) == 0) { gain_code_old_CN = *gain_code; move16 (); } } else { test (); test (); logic16 (); if (((rxdtx_ctrl & RX_FIRST_SID_UPDATE) != 0) && (i_subfr == 0)) { gain_code_new_CN = mult (gcode0_CN, qua_gain_code[index]); /*---------------------------------------------------------------* * reset table of past quantized energies * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * *---------------------------------------------------------------*/ for (i = 0; i < 4; i++) { past_qua_en[i] = -2381; move16 (); } } test (); test (); logic16 (); if (((rxdtx_ctrl & RX_CONT_SID_UPDATE) != 0) && (i_subfr == 0)) { gain_code_old_CN = gain_code_new_CN; move16 (); gain_code_new_CN = mult (gcode0_CN, qua_gain_code[index]); move16 (); } test (); if (i_subfr == 0) { *gain_code = interpolate_CN_param (gain_code_old_CN, gain_code_new_CN, rx_dtx_state); move16 (); } else { *gain_code = prev_gc; move16 (); } } past_gain_code = *gain_code; move16 (); for (i = 1; i < 5; i++) { gbuf[i - 1] = gbuf[i]; move16 (); } gbuf[4] = past_gain_code; move16 (); prev_gc = past_gain_code; move16 (); return; }