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Diffstat (limited to 'media/libstagefright/codecs/amrnb/enc/src/qgain795.cpp')
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diff --git a/media/libstagefright/codecs/amrnb/enc/src/qgain795.cpp b/media/libstagefright/codecs/amrnb/enc/src/qgain795.cpp new file mode 100644 index 0000000..d09fbe3 --- /dev/null +++ b/media/libstagefright/codecs/amrnb/enc/src/qgain795.cpp @@ -0,0 +1,904 @@ +/* ------------------------------------------------------------------ + * Copyright (C) 1998-2009 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/qgain795.c + Functions: MR795_gain_code_quant3 + MR795_gain_code_quant_mod + MR795_gain_quant + + Date: 02/04/2002 + +------------------------------------------------------------------------------ + REVISION HISTORY + + Description: Updated template used to PV coding template. + Changed to accept the pOverflow flag for EPOC compatibility. + + Description: + (1) Removed optimization -- mult(i, 3, pOverflow) is NOT the same as adding + i to itself 3 times. The reason is because the mult function does a + right shift by 15, which will obliterate smaller numbers. + + 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: Changed round function name to pv_round to avoid conflict with + round function in C standard library. + + Description: Added #ifdef __cplusplus around extern'ed table. + + Description: + +------------------------------------------------------------------------------ + MODULE DESCRIPTION + + +------------------------------------------------------------------------------ +*/ + +/*---------------------------------------------------------------------------- +; INCLUDES +----------------------------------------------------------------------------*/ +#include "qgain795.h" +#include "typedef.h" +#include "basic_op.h" +#include "cnst.h" +#include "log2.h" +#include "pow2.h" +#include "sqrt_l.h" +#include "g_adapt.h" +#include "calc_en.h" +#include "q_gain_p.h" + + +/*--------------------------------------------------------------------------*/ +#ifdef __cplusplus +extern "C" +{ +#endif + + /*---------------------------------------------------------------------------- + ; MACROS + ; Define module specific macros here + ----------------------------------------------------------------------------*/ + + /*---------------------------------------------------------------------------- + ; DEFINES + ; Include all pre-processor statements here. Include conditional + ; compile variables also. + ----------------------------------------------------------------------------*/ +#define NB_QUA_CODE 32 + + /*---------------------------------------------------------------------------- + ; 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 + ----------------------------------------------------------------------------*/ + extern const Word16 qua_gain_code[NB_QUA_CODE*3]; + + + /*--------------------------------------------------------------------------*/ +#ifdef __cplusplus +} +#endif + +/* +------------------------------------------------------------------------------ + FUNCTION NAME: MR795_gain_code_quant3 +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS + + Inputs: + exp_gcode0 -- Word16 -- predicted CB gain (exponent), Q0 + gcode0 -- Word16 -- predicted CB gain (norm.) + g_pitch_cand[] -- Word16 array -- Pitch gain candidates (3), Q14 + g_pitch_cind[] -- Word16 array -- Pitch gain cand. indices (3), Q0 + frac_coeff[] -- Word16 array -- coefficients (5), Q15 + exp_coeff[] -- Word16 array -- energy coefficients (5), Q0 + coefficients from calc_filt_ener() + + Outputs: + gain_pit -- Pointer to Word16 -- Pitch gain, Q14 + gain_pit_ind -- Pointer to Word16 -- Pitch gain index, Q0 + gain_cod -- Pointer to Word16 -- Code gain, Q1 + gain_cod_ind -- Pointer to Word16 -- Code gain index, Q0 + qua_ener_MR122 -- Pointer to Word16 -- quantized energy error, Q10 + (for MR122 MA predictor update) + + qua_ener -- Pointer to Word16 -- quantized energy error, Q10 + (for other MA predictor update) + + pOverflow -- Pointer to Flag -- overflow indicator + + Returns: + None + + Global Variables Used: + None + + Local Variables Needed: + None + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + PURPOSE: Pre-quantization of codebook gains, given three possible + LTP gains (using predicted codebook gain) +------------------------------------------------------------------------------ + REQUIREMENTS + + None + +------------------------------------------------------------------------------ + REFERENCES + + qgain795.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] + +------------------------------------------------------------------------------ +*/ + +static void +MR795_gain_code_quant3( + Word16 exp_gcode0, /* i : predicted CB gain (exponent), Q0 */ + Word16 gcode0, /* i : predicted CB gain (norm.), Q14 */ + Word16 g_pitch_cand[], /* i : Pitch gain candidates (3), Q14 */ + Word16 g_pitch_cind[], /* i : Pitch gain cand. indices (3), Q0 */ + Word16 frac_coeff[], /* i : coefficients (5), Q15 */ + Word16 exp_coeff[], /* i : energy coefficients (5), Q0 */ + /* coefficients from calc_filt_ener()*/ + Word16 *gain_pit, /* o : Pitch gain, Q14 */ + Word16 *gain_pit_ind, /* o : Pitch gain index, Q0 */ + Word16 *gain_cod, /* o : Code gain, Q1 */ + Word16 *gain_cod_ind, /* o : Code gain index, Q0 */ + Word16 *qua_ener_MR122, /* o : quantized energy error, Q10 */ + /* (for MR122 MA predictor update) */ + Word16 *qua_ener, /* o : quantized energy error, Q10 */ + /* (for other MA predictor update) */ + Flag *pOverflow /* o : overflow indicator */ +) +{ + const Word16 *p; + Word16 i; + Word16 j; + Word16 cod_ind; + Word16 pit_ind; + Word16 e_max; + Word16 exp_code; + Word16 g_pitch; + Word16 g2_pitch; + Word16 g_code; + Word16 g2_code_h; + Word16 g2_code_l; + Word16 g_pit_cod_h; + Word16 g_pit_cod_l; + Word16 coeff[5]; + Word16 coeff_lo[5]; + Word16 exp_max[5]; + Word32 L_tmp; + Word32 L_tmp0; + Word32 dist_min; + + /* + * The error energy (sum) to be minimized consists of five terms, t[0..4]. + * + * t[0] = gp^2 * <y1 y1> + * t[1] = -2*gp * <xn y1> + * t[2] = gc^2 * <y2 y2> + * t[3] = -2*gc * <xn y2> + * t[4] = 2*gp*gc * <y1 y2> + * + */ + + /* determine the scaling exponent for g_code: ec = ec0 - 10 */ + exp_code = sub(exp_gcode0, 10, pOverflow); + + /* calculate exp_max[i] = s[i]-1 */ + exp_max[0] = sub(exp_coeff[0], 13, pOverflow); + exp_max[1] = sub(exp_coeff[1], 14, pOverflow); + exp_max[2] = add(exp_coeff[2], add(15, shl(exp_code, 1, pOverflow), pOverflow), pOverflow); + exp_max[3] = add(exp_coeff[3], exp_code, pOverflow); + exp_max[4] = add(exp_coeff[4], add(exp_code, 1, pOverflow), pOverflow); + + + /*-------------------------------------------------------------------* + * Find maximum exponent: * + * ~~~~~~~~~~~~~~~~~~~~~~ * + * * + * For the sum operation, all terms must have the same scaling; * + * that scaling should be low enough to prevent overflow. There- * + * fore, the maximum scale is determined and all coefficients are * + * re-scaled: * + * * + * e_max = max(exp_max[i]) + 1; * + * e = exp_max[i]-e_max; e <= 0! * + * c[i] = c[i]*2^e * + *-------------------------------------------------------------------*/ + + e_max = exp_max[0]; + for (i = 1; i < 5; i++) /* implemented flattened */ + { + if (exp_max[i] > e_max) + { + e_max = exp_max[i]; + } + } + + e_max = add(e_max, 1, pOverflow); /* To avoid overflow */ + + for (i = 0; i < 5; i++) + { + j = sub(e_max, exp_max[i], pOverflow); + L_tmp = L_deposit_h(frac_coeff[i]); + L_tmp = L_shr(L_tmp, j, pOverflow); + L_Extract(L_tmp, &coeff[i], &coeff_lo[i], pOverflow); + } + + + /*-------------------------------------------------------------------* + * Codebook search: * + * ~~~~~~~~~~~~~~~~ * + * * + * For each of the candiates LTP gains in g_pitch_cand[], the terms * + * t[0..4] are calculated from the values in the table (and the * + * pitch gain candidate) and summed up; the result is the mean * + * squared error for the LPT/CB gain pair. The index for the mini- * + * mum MSE is stored and finally used to retrieve the quantized CB * + * gain * + *-------------------------------------------------------------------*/ + + /* start with "infinite" MSE */ + dist_min = MAX_32; + cod_ind = 0; + pit_ind = 0; + + /* loop through LTP gain candidates */ + for (j = 0; j < 3; j++) + { + /* pre-calculate terms only dependent on pitch gain */ + g_pitch = g_pitch_cand[j]; + g2_pitch = mult(g_pitch, g_pitch, pOverflow); + L_tmp0 = Mpy_32_16(coeff[0], coeff_lo[0], g2_pitch, pOverflow); + L_tmp0 = Mac_32_16(L_tmp0, coeff[1], coeff_lo[1], g_pitch, pOverflow); + + p = &qua_gain_code[0]; + for (i = 0; i < NB_QUA_CODE; i++) + { + g_code = *p++; /* this is g_fac Q11 */ + p++; /* skip log2(g_fac) */ + p++; /* skip 20*log10(g_fac) */ + + g_code = mult(g_code, gcode0, pOverflow); + + L_tmp = L_mult(g_code, g_code, pOverflow); + L_Extract(L_tmp, &g2_code_h, &g2_code_l, pOverflow); + + L_tmp = L_mult(g_code, g_pitch, pOverflow); + L_Extract(L_tmp, &g_pit_cod_h, &g_pit_cod_l, pOverflow); + + L_tmp = Mac_32(L_tmp0, coeff[2], coeff_lo[2], + g2_code_h, g2_code_l, pOverflow); + L_tmp = Mac_32_16(L_tmp, coeff[3], coeff_lo[3], + g_code, pOverflow); + L_tmp = Mac_32(L_tmp, coeff[4], coeff_lo[4], + g_pit_cod_h, g_pit_cod_l, pOverflow); + + /* store table index if MSE for this index is lower + than the minimum MSE seen so far; also store the + pitch gain for this (so far) lowest MSE */ + if (L_tmp < dist_min) + { + dist_min = L_tmp; + cod_ind = i; + pit_ind = j; + } + } + } + + /*------------------------------------------------------------------* + * read quantized gains and new values for MA predictor memories * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * + *------------------------------------------------------------------*/ + + /* Read the quantized gains */ + p = &qua_gain_code[ + add(add(cod_ind, cod_ind, pOverflow), cod_ind, pOverflow)]; + + g_code = *p++; + *qua_ener_MR122 = *p++; + *qua_ener = *p; + + /*------------------------------------------------------------------* + * calculate final fixed codebook gain: * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * + * * + * gc = gc0 * g * + *------------------------------------------------------------------*/ + + L_tmp = L_mult(g_code, gcode0, pOverflow); + L_tmp = L_shr(L_tmp, sub(9, exp_gcode0, pOverflow), pOverflow); + *gain_cod = extract_h(L_tmp); + *gain_cod_ind = cod_ind; + *gain_pit = g_pitch_cand[pit_ind]; + *gain_pit_ind = g_pitch_cind[pit_ind]; +} + + +/* +------------------------------------------------------------------------------ + FUNCTION NAME: MR795_gain_code_quant_mod +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS + + Inputs: + gain_pit -- Word16 -- pitch gain, Q14 + exp_gcode0 -- Word16 -- predicted CB gain (exponent), Q0 + gcode0 -- Word16 -- predicted CB gain (norm.), Q14 + frac_en[] -- Word16 array -- energy coefficients (4), fraction part, Q15 + exp_en[] -- Word16 array -- energy coefficients (4), exponent part, Q0 + alpha -- Word16 -- gain adaptor factor (>0), Q15 + + gain_cod_unq -- Word16 -- Code gain (unquantized) + (scaling: Q10 - exp_gcode0) + + gain_cod -- Pointer to Word16 -- Code gain (pre-/quantized), Q1 + + Outputs: + qua_ener_MR122 -- Pointer to Word16 -- quantized energy error, Q10 + (for MR122 MA predictor update) + qua_ener -- Pointer to Word16 -- quantized energy error, Q10 + (for other MA predictor update) + pOverflow -- Pointer to Flag -- overflow indicator + + Returns: + index of quantization (Word16) + + Global Variables Used: + None + + Local Variables Needed: + None + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + PURPOSE: Modified quantization of the MR795 codebook gain + + Uses pre-computed energy coefficients in frac_en[]/exp_en[] + + 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] = <code code> // CB innovation energy +------------------------------------------------------------------------------ + REQUIREMENTS + + None + +------------------------------------------------------------------------------ + REFERENCES + + qgain795.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] + +------------------------------------------------------------------------------ +*/ + +static Word16 +MR795_gain_code_quant_mod( /* o : index of quantization. */ + Word16 gain_pit, /* i : pitch gain, Q14 */ + Word16 exp_gcode0, /* i : predicted CB gain (exponent), Q0 */ + Word16 gcode0, /* i : predicted CB gain (norm.), Q14 */ + Word16 frac_en[], /* i : energy coefficients (4), + fraction part, Q15 */ + Word16 exp_en[], /* i : energy coefficients (4), + eponent part, Q0 */ + Word16 alpha, /* i : gain adaptor factor (>0), Q15 */ + Word16 gain_cod_unq, /* i : Code gain (unquantized) */ + /* (scaling: Q10 - exp_gcode0) */ + Word16 *gain_cod, /* i/o: Code gain (pre-/quantized), Q1 */ + Word16 *qua_ener_MR122, /* o : quantized energy error, Q10 */ + /* (for MR122 MA predictor update) */ + Word16 *qua_ener, /* o : quantized energy error, Q10 */ + /* (for other MA predictor update) */ + Flag *pOverflow /* o : overflow indicator */ +) +{ + const Word16 *p; + Word16 i; + Word16 index; + Word16 tmp; + Word16 one_alpha; + Word16 exp; + Word16 e_max; + + Word16 g2_pitch; + Word16 g_code; + Word16 g2_code_h; + Word16 g2_code_l; + Word16 d2_code_h; + Word16 d2_code_l; + Word16 coeff[5]; + Word16 coeff_lo[5]; + Word16 exp_coeff[5]; + Word32 L_tmp; + Word32 L_t0; + Word32 L_t1; + Word32 dist_min; + Word16 gain_code; + + /* + Steps in calculation of the error criterion (dist): + --------------------------------------------------- + + underlined = constant; alp = FLP value of alpha, alpha = FIP + ---------- + + + ExEn = gp^2 * LtpEn + 2.0*gp*gc[i] * XC + gc[i]^2 * InnEn; + ------------ ------ -- ----- + + aExEn= alp * ExEn + = alp*gp^2*LtpEn + 2.0*alp*gp*XC* gc[i] + alp*InnEn* gc[i]^2 + -------------- ------------- --------- + + = t[1] + t[2] + t[3] + + dist = d1 + d2; + + d1 = (1.0 - alp) * InnEn * (gcu - gc[i])^2 = t[4] + ------------------- --- + + d2 = alp * (ResEn - 2.0 * sqrt(ResEn*ExEn) + ExEn); + --- ----- --- ----- + + = alp * (sqrt(ExEn) - sqrt(ResEn))^2 + --- ----------- + + = (sqrt(aExEn) - sqrt(alp*ResEn))^2 + --------------- + + = (sqrt(aExEn) - t[0] )^2 + ---- + + */ + + /* + * calculate scalings of the constant terms + */ + gain_code = shl(*gain_cod, sub(10, exp_gcode0, pOverflow), pOverflow); /* Q1 -> Q11 (-ec0) */ + g2_pitch = mult(gain_pit, gain_pit, pOverflow); /* Q14 -> Q13 */ + /* 0 < alpha <= 0.5 => 0.5 <= 1-alpha < 1, i.e one_alpha is normalized */ + one_alpha = add(sub(32767, alpha, pOverflow), 1, pOverflow); /* 32768 - alpha */ + + + /* alpha <= 0.5 -> mult. by 2 to keep precision; compensate in exponent */ + L_t1 = L_mult(alpha, frac_en[1], pOverflow); + L_t1 = L_shl(L_t1, 1, pOverflow); + tmp = extract_h(L_t1); + + /* directly store in 32 bit variable because no further mult. required */ + L_t1 = L_mult(tmp, g2_pitch, pOverflow); + exp_coeff[1] = sub(exp_en[1], 15, pOverflow); + + + tmp = extract_h(L_shl(L_mult(alpha, frac_en[2], pOverflow), 1, pOverflow)); + coeff[2] = mult(tmp, gain_pit, pOverflow); + exp = sub(exp_gcode0, 10, pOverflow); + exp_coeff[2] = add(exp_en[2], exp, pOverflow); + + + /* alpha <= 0.5 -> mult. by 2 to keep precision; compensate in exponent */ + coeff[3] = extract_h(L_shl(L_mult(alpha, frac_en[3], pOverflow), 1, pOverflow)); + exp = sub(shl(exp_gcode0, 1, pOverflow), 7, pOverflow); + exp_coeff[3] = add(exp_en[3], exp, pOverflow); + + + coeff[4] = mult(one_alpha, frac_en[3], pOverflow); + exp_coeff[4] = add(exp_coeff[3], 1, pOverflow); + + + L_tmp = L_mult(alpha, frac_en[0], pOverflow); + /* sqrt_l returns normalized value and 2*exponent + -> result = val >> (exp/2) + exp_coeff holds 2*exponent for c[0] */ + /* directly store in 32 bit variable because no further mult. required */ + L_t0 = sqrt_l_exp(L_tmp, &exp, pOverflow); /* normalization included in sqrt_l_exp */ + exp = add(exp, 47, pOverflow); + exp_coeff[0] = sub(exp_en[0], exp, pOverflow); + + /* + * Determine the maximum exponent occuring in the distance calculation + * and adjust all fractions accordingly (including a safety margin) + * + */ + + /* find max(e[1..4],e[0]+31) */ + e_max = add(exp_coeff[0], 31, pOverflow); + for (i = 1; i <= 4; i++) + { + if (exp_coeff[i] > e_max) + { + e_max = exp_coeff[i]; + } + } + + /* scale c[1] (requires no further multiplication) */ + tmp = sub(e_max, exp_coeff[1], pOverflow); + L_t1 = L_shr(L_t1, tmp, pOverflow); + + /* scale c[2..4] (used in Mpy_32_16 in the quantizer loop) */ + for (i = 2; i <= 4; i++) + { + tmp = sub(e_max, exp_coeff[i], pOverflow); + L_tmp = L_deposit_h(coeff[i]); + L_tmp = L_shr(L_tmp, tmp, pOverflow); + L_Extract(L_tmp, &coeff[i], &coeff_lo[i], pOverflow); + } + + /* scale c[0] (requires no further multiplication) */ + exp = sub(e_max, 31, pOverflow); /* new exponent */ + tmp = sub(exp, exp_coeff[0], pOverflow); + L_t0 = L_shr(L_t0, shr(tmp, 1, pOverflow), pOverflow); + /* perform correction by 1/sqrt(2) if exponent difference is odd */ + if ((tmp & 0x1) != 0) + { + L_Extract(L_t0, &coeff[0], &coeff_lo[0], pOverflow); + L_t0 = Mpy_32_16(coeff[0], coeff_lo[0], + 23170, pOverflow); /* 23170 Q15 = 1/sqrt(2)*/ + } + + /* search the quantizer table for the lowest value + of the search criterion */ + dist_min = MAX_32; + index = 0; + p = &qua_gain_code[0]; + + for (i = 0; i < NB_QUA_CODE; i++) + { + g_code = *p++; /* this is g_fac (Q11) */ + p++; /* skip log2(g_fac) */ + p++; /* skip 20*log10(g_fac) */ + g_code = mult(g_code, gcode0, pOverflow); + + /* only continue if gc[i] < 2.0*gc + which is equiv. to g_code (Q10-ec0) < gain_code (Q11-ec0) */ + + if (g_code >= gain_code) + { + break; + } + + L_tmp = L_mult(g_code, g_code, pOverflow); + L_Extract(L_tmp, &g2_code_h, &g2_code_l, pOverflow); + + tmp = sub(g_code, gain_cod_unq, pOverflow); + L_tmp = L_mult(tmp, tmp, pOverflow); + L_Extract(L_tmp, &d2_code_h, &d2_code_l, pOverflow); + + /* t2, t3, t4 */ + L_tmp = Mac_32_16(L_t1, coeff[2], coeff_lo[2], g_code, pOverflow); + L_tmp = Mac_32(L_tmp, coeff[3], coeff_lo[3], g2_code_h, g2_code_l, pOverflow); + + L_tmp = sqrt_l_exp(L_tmp, &exp, pOverflow); + L_tmp = L_shr(L_tmp, shr(exp, 1, pOverflow), pOverflow); + + /* d2 */ + tmp = pv_round(L_sub(L_tmp, L_t0, pOverflow), pOverflow); + L_tmp = L_mult(tmp, tmp, pOverflow); + + /* dist */ + L_tmp = Mac_32(L_tmp, coeff[4], coeff_lo[4], d2_code_h, d2_code_l, pOverflow); + + /* store table index if distance measure for this + index is lower than the minimum seen so far */ + if (L_tmp < dist_min) + { + dist_min = L_tmp; + index = i; + } + } + + /*------------------------------------------------------------------* + * read quantized gains and new values for MA predictor memories * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * + *------------------------------------------------------------------*/ + + /* Read the quantized gains */ + p = &qua_gain_code[add(add(index, index, pOverflow), index, pOverflow)]; + g_code = *p++; + *qua_ener_MR122 = *p++; + *qua_ener = *p; + + /*------------------------------------------------------------------* + * calculate final fixed codebook gain: * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * + * * + * gc = gc0 * g * + *------------------------------------------------------------------*/ + + L_tmp = L_mult(g_code, gcode0, pOverflow); + L_tmp = L_shr(L_tmp, sub(9, exp_gcode0, pOverflow), pOverflow); + *gain_cod = extract_h(L_tmp); + + return index; +} + +/* +------------------------------------------------------------------------------ + FUNCTION NAME: MR795_gain_quant +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS +MR795_gain_quant( + + + Inputs: + adapt_st -- Pointer to GainAdaptState -- gain adapter state structure + res -- Word16 array -- LP residual, Q0 + exc -- Word16 array -- LTP excitation (unfiltered), Q0 + code -- Word16 array -- CB innovation (unfiltered), Q13 + frac_coeff -- Word16 array -- coefficients (5), Q15 + exp_coeff -- Word16 array -- energy coefficients (5), Q0 + coefficients from calc_filt_ener() + exp_code_en -- Word16 -- innovation energy (exponent), Q0 + frac_code_en -- Word16 -- innovation energy (fraction), Q15 + exp_gcode0 -- Word16 -- predicted CB gain (exponent), Q0 + frac_gcode0 -- Word16 -- predicted CB gain (fraction), Q15 + L_subfr -- Word16 -- Subframe length + cod_gain_frac -- Word16 -- opt. codebook gain (fraction),Q15 + cod_gain_exp -- Word16 -- opt. codebook gain (exponent), Q0 + gp_limit -- Word16 -- pitch gain limit + gain_pit -- Pointer to Word16 -- Pitch gain, Q14 + + Output + adapt_st -- Pointer to GainAdaptState -- gain adapter state structure + gain_pit -- Pointer to Word16 -- Pitch gain, Q14 + + gain_pit -- Pointer to Word16 -- Pitch gain, Q14 + gain_cod -- Pointer to Word16 -- Code gain, Q1 + qua_ener_MR122 -- Pointer to Word16 -- quantized energy error, Q10 + (for MR122 MA predictor update) + + qua_ener -- Pointer to Word16 -- quantized energy error, Q10 + (for other MA predictor update) + + anap -- Double Pointer to Word16 -- Index of quantization + (first gain pitch, then code pitch) + + pOverflow -- Pointer to Flag -- overflow indicator + + Returns: + None + + Global Variables Used: + None + + Local Variables Needed: + None + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + pitch and codebook quantization for MR795 +------------------------------------------------------------------------------ + REQUIREMENTS + + None + +------------------------------------------------------------------------------ + REFERENCES + + qgain795.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] + +------------------------------------------------------------------------------ +*/ + +void +MR795_gain_quant( + GainAdaptState *adapt_st, /* i/o: gain adapter state structure */ + Word16 res[], /* i : LP residual, Q0 */ + Word16 exc[], /* i : LTP excitation (unfiltered), Q0 */ + Word16 code[], /* i : CB innovation (unfiltered), Q13 */ + Word16 frac_coeff[], /* i : coefficients (5), Q15 */ + Word16 exp_coeff[], /* i : energy coefficients (5), Q0 */ + /* coefficients from calc_filt_ener() */ + Word16 exp_code_en, /* i : innovation energy (exponent), Q0 */ + Word16 frac_code_en, /* i : innovation energy (fraction), Q15 */ + Word16 exp_gcode0, /* i : predicted CB gain (exponent), Q0 */ + Word16 frac_gcode0, /* i : predicted CB gain (fraction), Q15 */ + Word16 L_subfr, /* i : Subframe length */ + Word16 cod_gain_frac, /* i : opt. codebook gain (fraction),Q15 */ + Word16 cod_gain_exp, /* i : opt. codebook gain (exponent), Q0 */ + Word16 gp_limit, /* i : pitch gain limit */ + Word16 *gain_pit, /* i/o: Pitch gain, Q14 */ + Word16 *gain_cod, /* o : Code gain, Q1 */ + Word16 *qua_ener_MR122, /* o : quantized energy error, Q10 */ + /* (for MR122 MA predictor update) */ + Word16 *qua_ener, /* o : quantized energy error, Q10 */ + /* (for other MA predictor update) */ + Word16 **anap, /* o : Index of quantization */ + /* (first gain pitch, then code pitch)*/ + Flag *pOverflow /* o : overflow indicator */ +) +{ + Word16 frac_en[4]; + Word16 exp_en[4]; + Word16 ltpg, alpha, gcode0; + Word16 g_pitch_cand[3]; /* pitch gain candidates Q14 */ + Word16 g_pitch_cind[3]; /* pitch gain indices Q0 */ + Word16 gain_pit_index; + Word16 gain_cod_index; + Word16 exp; + Word16 gain_cod_unq; /* code gain (unq.) Q(10-exp_gcode0) */ + + + /* get list of candidate quantized pitch gain values + * and corresponding quantization indices + */ + gain_pit_index = q_gain_pitch(MR795, gp_limit, gain_pit, + g_pitch_cand, g_pitch_cind, pOverflow); + + /*-------------------------------------------------------------------* + * predicted codebook gain * + * ~~~~~~~~~~~~~~~~~~~~~~~ * + * gc0 = 2^exp_gcode0 + 2^frac_gcode0 * + * * + * gcode0 (Q14) = 2^14*2^frac_gcode0 = gc0 * 2^(14-exp_gcode0) * + *-------------------------------------------------------------------*/ + gcode0 = (Word16)(Pow2(14, frac_gcode0, pOverflow)); /* Q14 */ + + /* pre-quantization of codebook gain + * (using three pitch gain candidates); + * result: best guess of pitch gain and code gain + */ + MR795_gain_code_quant3( + exp_gcode0, gcode0, g_pitch_cand, g_pitch_cind, + frac_coeff, exp_coeff, + gain_pit, &gain_pit_index, gain_cod, &gain_cod_index, + qua_ener_MR122, qua_ener, pOverflow); + + /* calculation of energy coefficients and LTP coding gain */ + calc_unfilt_energies(res, exc, code, *gain_pit, L_subfr, + frac_en, exp_en, <pg, pOverflow); + + /* run gain adaptor, calculate alpha factor to balance LTP/CB gain + * (this includes the gain adaptor update) + * Note: ltpg = 0 if frac_en[0] == 0, so the update is OK in that case + */ + gain_adapt(adapt_st, ltpg, *gain_cod, &alpha, pOverflow); + + /* if this is a very low energy signal (threshold: see + * calc_unfilt_energies) or alpha <= 0 then don't run the modified quantizer + */ + if (frac_en[0] != 0 && alpha > 0) + { + /* innovation energy <cod cod> was already computed in gc_pred() */ + /* (this overwrites the LtpResEn which is no longer needed) */ + frac_en[3] = frac_code_en; + exp_en[3] = exp_code_en; + + /* store optimum codebook gain in Q(10-exp_gcode0) */ + exp = add(sub(cod_gain_exp, exp_gcode0, pOverflow), 10, pOverflow); + gain_cod_unq = shl(cod_gain_frac, exp, pOverflow); + + /* run quantization with modified criterion */ + gain_cod_index = MR795_gain_code_quant_mod( + *gain_pit, exp_gcode0, gcode0, + frac_en, exp_en, alpha, gain_cod_unq, + gain_cod, qua_ener_MR122, qua_ener, pOverflow); /* function result */ + } + + *(*anap)++ = gain_pit_index; + *(*anap)++ = gain_cod_index; +} |