| /* ------------------------------------------------------------------ |
| * 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; |
| } |
