FreeCalypso > hg > gsm-codec-lib
view libtwamr/calc_en.c @ 466:0c4e1bc06740
amrefr-encode-r: use the new DHF xform that matches T-Mobile
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Sun, 12 May 2024 21:44:59 +0000 |
parents | 2df212a012af |
children |
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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 : calc_en.c * Purpose : (pre-) quantization of pitch gain for MR795 * ******************************************************************************** */ /* ******************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ******************************************************************************** */ #include "namespace.h" #include "calc_en.h" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #include "basic_op.h" #include "oper_32b.h" #include "no_count.h" #include "cnst.h" #include "log2.h" /* ******************************************************************************** * PUBLIC PROGRAM CODE ******************************************************************************** */ /************************************************************************* * * FUNCTION: calc_unfilt_energies * * PURPOSE: calculation of several energy coefficients for unfiltered * excitation signals and the LTP coding gain * * frac_en[0]*2^exp_en[0] = <res res> // LP residual energy * frac_en[1]*2^exp_en[1] = <exc exc> // LTP residual energy * frac_en[2]*2^exp_en[2] = <exc code> // LTP/CB innovation dot product * frac_en[3]*2^exp_en[3] = <lres lres> // LTP residual energy * // (lres = res - gain_pit*exc) * ltpg = log2(LP_res_en / LTP_res_en) * *************************************************************************/ void calc_unfilt_energies( Word16 res[], /* i : LP residual, Q0 */ Word16 exc[], /* i : LTP excitation (unfiltered), Q0 */ Word16 code[], /* i : CB innovation (unfiltered), Q13 */ Word16 gain_pit, /* i : pitch gain, Q14 */ Word16 L_subfr, /* i : Subframe length */ Word16 frac_en[], /* o : energy coefficients (4), fraction part, Q15 */ Word16 exp_en[], /* o : energy coefficients (4), exponent part, Q0 */ Word16 *ltpg /* o : LTP coding gain (log2()), Q13 */ ) { Word32 s, L_temp; Word16 i, exp, tmp; Word16 ltp_res_en, pred_gain; Word16 ltpg_exp, ltpg_frac; /* Compute residual energy */ s = L_mac((Word32) 0, res[0], res[0]); for (i = 1; i < L_subfr; i++) s = L_mac(s, res[i], res[i]); /* ResEn := 0 if ResEn < 200.0 (= 400 Q1) */ test(); if (L_sub (s, 400L) < 0) { frac_en[0] = 0; move16 (); exp_en[0] = -15; move16 (); } else { exp = norm_l(s); frac_en[0] = extract_h(L_shl(s, exp)); move16 (); exp_en[0] = sub(15, exp); move16 (); } /* Compute ltp excitation energy */ s = L_mac((Word32) 0, exc[0], exc[0]); for (i = 1; i < L_subfr; i++) s = L_mac(s, exc[i], exc[i]); exp = norm_l(s); frac_en[1] = extract_h(L_shl(s, exp)); move16 (); exp_en[1] = sub(15, exp); move16 (); /* Compute scalar product <exc[],code[]> */ s = L_mac((Word32) 0, exc[0], code[0]); for (i = 1; i < L_subfr; i++) s = L_mac(s, exc[i], code[i]); exp = norm_l(s); frac_en[2] = extract_h(L_shl(s, exp)); move16 (); exp_en[2] = sub(16-14, exp); move16 (); /* Compute energy of LTP residual */ s = 0L; move32 (); for (i = 0; i < L_subfr; i++) { L_temp = L_mult(exc[i], gain_pit); L_temp = L_shl(L_temp, 1); tmp = sub(res[i], round(L_temp)); /* LTP residual, Q0 */ s = L_mac (s, tmp, tmp); } exp = norm_l(s); ltp_res_en = extract_h (L_shl (s, exp)); exp = sub (15, exp); frac_en[3] = ltp_res_en; move16 (); exp_en[3] = exp; move16 (); /* calculate LTP coding gain, i.e. energy reduction LP res -> LTP res */ test (); test (); if (ltp_res_en > 0 && frac_en[0] != 0) { /* gain = ResEn / LTPResEn */ pred_gain = div_s (shr (frac_en[0], 1), ltp_res_en); exp = sub (exp, exp_en[0]); /* L_temp = ltpGain * 2^(30 + exp) */ L_temp = L_deposit_h (pred_gain); /* L_temp = ltpGain * 2^27 */ L_temp = L_shr (L_temp, add (exp, 3)); /* Log2 = log2() + 27 */ Log2(L_temp, <pg_exp, <pg_frac); /* ltpg = log2(LtpGain) * 2^13 --> range: +- 4 = +- 12 dB */ L_temp = L_Comp (sub (ltpg_exp, 27), ltpg_frac); *ltpg = round (L_shl (L_temp, 13)); /* Q13 */ } else { *ltpg = 0; move16 (); } } /************************************************************************* * * FUNCTION: calc_filt_energies * * PURPOSE: calculation of several energy coefficients for filtered * excitation signals * * Compute coefficients need for the quantization and the optimum * codebook gain gcu (for MR475 only). * * coeff[0] = y1 y1 * coeff[1] = -2 xn y1 * coeff[2] = y2 y2 * coeff[3] = -2 xn y2 * coeff[4] = 2 y1 y2 * * * gcu = <xn2, y2> / <y2, y2> (0 if <xn2, y2> <= 0) * * Product <y1 y1> and <xn y1> have been computed in G_pitch() and * are in vector g_coeff[]. * *************************************************************************/ void calc_filt_energies( enum Mode mode, /* i : coder mode */ Word16 xn[], /* i : LTP target vector, Q0 */ Word16 xn2[], /* i : CB target vector, Q0 */ Word16 y1[], /* i : Adaptive codebook, Q0 */ Word16 Y2[], /* i : Filtered innovative vector, Q12 */ Word16 g_coeff[], /* i : Correlations <xn y1> <y1 y1> */ /* computed in G_pitch() */ Word16 frac_coeff[],/* o : energy coefficients (5), fraction part, Q15 */ Word16 exp_coeff[], /* o : energy coefficients (5), exponent part, Q0 */ Word16 *cod_gain_frac,/* o: optimum codebook gain (fraction part), Q15 */ Word16 *cod_gain_exp /* o: optimum codebook gain (exponent part), Q0 */ ) { Word32 s, ener_init; Word16 i, exp, frac; Word16 y2[L_SUBFR]; if (test(), sub(mode, MR795) == 0 || sub(mode, MR475) == 0) { ener_init = 0L; move32 (); } else { ener_init = 1L; move32 (); } for (i = 0; i < L_SUBFR; i++) { y2[i] = shr(Y2[i], 3); move16 (); } frac_coeff[0] = g_coeff[0]; move16 (); exp_coeff[0] = g_coeff[1]; move16 (); frac_coeff[1] = negate(g_coeff[2]); move16 (); /* coeff[1] = -2 xn y1 */ exp_coeff[1] = add(g_coeff[3], 1); move16 (); /* Compute scalar product <y2[],y2[]> */ s = L_mac(ener_init, y2[0], y2[0]); for (i = 1; i < L_SUBFR; i++) s = L_mac(s, y2[i], y2[i]); exp = norm_l(s); frac_coeff[2] = extract_h(L_shl(s, exp)); move16 (); exp_coeff[2] = sub(15 - 18, exp); move16(); /* Compute scalar product -2*<xn[],y2[]> */ s = L_mac(ener_init, xn[0], y2[0]); for (i = 1; i < L_SUBFR; i++) s = L_mac(s, xn[i], y2[i]); exp = norm_l(s); frac_coeff[3] = negate(extract_h(L_shl(s, exp))); move16 (); exp_coeff[3] = sub(15 - 9 + 1, exp); move16 (); /* Compute scalar product 2*<y1[],y2[]> */ s = L_mac(ener_init, y1[0], y2[0]); for (i = 1; i < L_SUBFR; i++) s = L_mac(s, y1[i], y2[i]); exp = norm_l(s); frac_coeff[4] = extract_h(L_shl(s, exp)); move16 (); exp_coeff[4] = sub(15 - 9 + 1, exp); move16(); if (test(), test (), sub(mode, MR475) == 0 || sub(mode, MR795) == 0) { /* Compute scalar product <xn2[],y2[]> */ s = L_mac(ener_init, xn2[0], y2[0]); for (i = 1; i < L_SUBFR; i++) s = L_mac(s, xn2[i], y2[i]); exp = norm_l(s); frac = extract_h(L_shl(s, exp)); exp = sub(15 - 9, exp); if (test (), frac <= 0) { *cod_gain_frac = 0; move16 (); *cod_gain_exp = 0; move16 (); } else { /* gcu = <xn2, y2> / c[2] = (frac>>1)/frac[2] * 2^(exp+1-exp[2]) = div_s(frac>>1, frac[2])*2^-15 * 2^(exp+1-exp[2]) = div_s * 2^(exp-exp[2]-14) */ *cod_gain_frac = div_s (shr (frac,1), frac_coeff[2]); move16 (); *cod_gain_exp = sub (sub (exp, exp_coeff[2]), 14); move16 (); } } } /************************************************************************* * * FUNCTION: calc_target_energy * * PURPOSE: calculation of target energy * * en = <xn, xn> * *************************************************************************/ void calc_target_energy( Word16 xn[], /* i: LTP target vector, Q0 */ Word16 *en_exp, /* o: optimum codebook gain (exponent part), Q0 */ Word16 *en_frac /* o: optimum codebook gain (fraction part), Q15 */ ) { Word32 s; Word16 i, exp; /* Compute scalar product <xn[], xn[]> */ s = L_mac(0L, xn[0], xn[0]); for (i = 1; i < L_SUBFR; i++) s = L_mac(s, xn[i], xn[i]); /* s = SUM 2*xn(i) * xn(i) = <xn xn> * 2 */ exp = norm_l(s); *en_frac = extract_h(L_shl(s, exp)); *en_exp = sub(16, exp); move16(); }