| /* ------------------------------------------------------------------ |
| * 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/g_pitch.c |
| |
| Date: 06/12/2000 |
| |
| ------------------------------------------------------------------------------ |
| REVISION HISTORY |
| |
| Description: Placed into template and began to optimize. |
| |
| Description: Synchronized file with UMTS version 3.2.0. Updated coding |
| template. Removed unnecessary include files. |
| |
| Description: Replaced basic_op.h and oper_32b.h with the header files of the |
| math functions used in the file. Fixed typecasting issue with |
| TI compiler. |
| |
| Description: Passing in pointer to overflow flag for EPOC compatibility. . |
| |
| Description: |
| 1. Eliminated unused include files. |
| 2. Replaced array addressing by pointers |
| 3. Eliminated math operations that unnecessary checked for |
| saturation, in some cases this by shifting before adding and |
| in other cases by evaluating the operands |
| 4. Unrolled loops to speed up processing |
| |
| 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: Using inlines from fxp_arithmetic.h . |
| |
| Description: Replacing fxp_arithmetic.h with basic_op.h. |
| |
| Description: |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| /*---------------------------------------------------------------------------- |
| ; INCLUDES |
| ----------------------------------------------------------------------------*/ |
| #include "g_pitch.h" |
| #include "mode.h" |
| #include "cnst.h" |
| #include "basic_op.h" |
| |
| /*---------------------------------------------------------------------------- |
| ; MACROS |
| ; Define module specific macros here |
| ----------------------------------------------------------------------------*/ |
| |
| |
| /*---------------------------------------------------------------------------- |
| ; DEFINES |
| ; Include all pre-processor statements here. Include conditional |
| ; compile variables also. |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL FUNCTION DEFINITIONS |
| ; Function Prototype declaration |
| ----------------------------------------------------------------------------*/ |
| |
| /*---------------------------------------------------------------------------- |
| ; LOCAL STORE/BUFFER/POINTER DEFINITIONS |
| ; Variable declaration - defined here and used outside this module |
| ----------------------------------------------------------------------------*/ |
| |
| |
| /* |
| ------------------------------------------------------------------------------ |
| FUNCTION NAME: G_pitch |
| ------------------------------------------------------------------------------ |
| INPUT AND OUTPUT DEFINITIONS |
| |
| Inputs: |
| mode = AMR mode (enum Mode) |
| xn = pointer to pitch target buffer (Word16) |
| y1 = pointer to filtered adaptive codebook buffer (Word16) |
| g_coeff = pointer to buffer of correlations needed for gain quantization |
| (Word16) |
| L_subfr = length of subframe (Word16) |
| pOverflow = pointer to overflow flag (Flag) |
| |
| Outputs: |
| g_coeff contains the mantissa and exponent of the two dot products. |
| pOverflow -> 1 if an overflow occurs |
| |
| Returns: |
| gain = ratio of dot products.(Word16) |
| |
| Global Variables Used: |
| None. |
| |
| Local Variables Needed: |
| None. |
| |
| ------------------------------------------------------------------------------ |
| FUNCTION DESCRIPTION |
| |
| This function computes the pitch (adaptive codebook) gain. The adaptive |
| codebook gain is given by |
| |
| g = <x[], y[]> / <y[], y[]> |
| |
| where: x[] is the target vector |
| y[] is the filtered adaptive codevector |
| <> denotes dot product. |
| |
| The gain is limited to the range [0,1.2] (=0..19661 Q14) |
| |
| ------------------------------------------------------------------------------ |
| REQUIREMENTS |
| |
| None. |
| |
| ------------------------------------------------------------------------------ |
| REFERENCES |
| |
| g_pitch.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 |
| |
| ------------------------------------------------------------------------------ |
| PSEUDO-CODE |
| |
| Word16 G_pitch ( // o : Gain of pitch lag saturated to 1.2 |
| enum Mode mode, // i : AMR mode |
| Word16 xn[], // i : Pitch target. |
| Word16 y1[], // i : Filtered adaptive codebook. |
| Word16 g_coeff[], // i : Correlations need for gain quantization |
| Word16 L_subfr // i : Length of subframe. |
| ) |
| { |
| Word16 i; |
| Word16 xy, yy, exp_xy, exp_yy, gain; |
| Word32 s; |
| |
| Word16 scaled_y1[L_SUBFR]; // Usually dynamic allocation of (L_subfr) |
| |
| // divide "y1[]" by 4 to avoid overflow |
| |
| // The reference ETSI code uses a global overflow Flag. However in the actual |
| // implementation a pointer to the overflow flag is passed into the function. |
| |
| for (i = 0; i < L_subfr; i++) |
| { |
| scaled_y1[i] = shr (y1[i], 2); |
| } |
| |
| // Compute scalar product <y1[],y1[]> |
| |
| // Q12 scaling / MR122 |
| Overflow = 0; |
| s = 1L; // Avoid case of all zeros |
| for (i = 0; i < L_subfr; i++) |
| { |
| s = L_mac (s, y1[i], y1[i]); |
| } |
| if (Overflow == 0) // Test for overflow |
| { |
| exp_yy = norm_l (s); |
| yy = pv_round (L_shl (s, exp_yy)); |
| } |
| else |
| { |
| s = 1L; // Avoid case of all zeros |
| for (i = 0; i < L_subfr; i++) |
| { |
| s = L_mac (s, scaled_y1[i], scaled_y1[i]); |
| } |
| exp_yy = norm_l (s); |
| yy = pv_round (L_shl (s, exp_yy)); |
| exp_yy = sub (exp_yy, 4); |
| } |
| |
| // Compute scalar product <xn[],y1[]> |
| |
| Overflow = 0; |
| s = 1L; // Avoid case of all zeros |
| |
| for (i = 0; i < L_subfr; i++) |
| { |
| s = L_mac(s, xn[i], y1[i]); |
| } |
| if (Overflow == 0) |
| { |
| exp_xy = norm_l (s); |
| xy = pv_round (L_shl (s, exp_xy)); |
| } |
| else |
| { |
| s = 1L; // Avoid case of all zeros |
| for (i = 0; i < L_subfr; i++) |
| { |
| s = L_mac (s, xn[i], scaled_y1[i]); |
| } |
| exp_xy = norm_l (s); |
| xy = pv_round (L_shl (s, exp_xy)); |
| exp_xy = sub (exp_xy, 2); |
| } |
| |
| g_coeff[0] = yy; |
| g_coeff[1] = sub (15, exp_yy); |
| g_coeff[2] = xy; |
| g_coeff[3] = sub (15, exp_xy); |
| |
| // If (xy < 4) gain = 0 |
| |
| i = sub (xy, 4); |
| |
| if (i < 0) |
| return ((Word16) 0); |
| |
| // compute gain = xy/yy |
| |
| xy = shr (xy, 1); // Be sure xy < yy |
| gain = div_s (xy, yy); |
| |
| i = sub (exp_xy, exp_yy); // Denormalization of division |
| gain = shr (gain, i); |
| |
| // if(gain >1.2) gain = 1.2 |
| |
| if (sub (gain, 19661) > 0) |
| { |
| gain = 19661; |
| } |
| |
| if (sub(mode, MR122) == 0) |
| { |
| // clear 2 LSBits |
| gain = gain & 0xfffC; |
| } |
| |
| return (gain); |
| } |
| |
| ------------------------------------------------------------------------------ |
| 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] |
| |
| ------------------------------------------------------------------------------ |
| */ |
| |
| Word16 G_pitch( /* o : Gain of pitch lag saturated to 1.2 */ |
| enum Mode mode, /* i : AMR mode */ |
| Word16 xn[], /* i : Pitch target. Q0 */ |
| Word16 y1[], /* i : Filtered adaptive codebook. Q12 */ |
| Word16 g_coeff[], /* i : Correlations need for gain quantization */ |
| Word16 L_subfr, /* i : Length of subframe. */ |
| Flag *pOverflow /* i/o : Overflow flag */ |
| ) |
| { |
| |
| Word16 i; |
| Word16 xy; |
| Word16 yy; |
| Word16 exp_xy; |
| Word16 exp_yy; |
| Word16 gain; |
| Word16 tmp; |
| Word32 s; |
| Word32 s1; |
| Word32 L_temp; /* Use this as an intermediate value */ |
| Word16 *p_xn = &xn[0]; |
| Word16 *p_y1 = &y1[0]; |
| |
| /* Compute scalar product <y1[],y1[]> */ |
| |
| /* Q12 scaling / MR122 */ |
| *pOverflow = 0; |
| s = 0; |
| |
| for (i = L_subfr >> 2; i != 0; i--) |
| { |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y1), (Word32) * (p_y1), s); |
| p_y1++; |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y1), (Word32) * (p_y1), s); |
| p_y1++; |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y1), (Word32) * (p_y1), s); |
| p_y1++; |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_y1), (Word32) * (p_y1), s); |
| p_y1++; |
| } |
| if ((s >= 0) & (s < 0x40000000)) |
| { |
| s <<= 1; |
| s += 1; /* Avoid case of all zeros */ |
| |
| exp_yy = norm_l(s); /* Note 0<=exp_yy <= 31 */ |
| L_temp = s << exp_yy; |
| yy = pv_round(L_temp, pOverflow); |
| } |
| else |
| { |
| s = 0; /* Avoid case of all zeros */ |
| p_y1 = &y1[0]; |
| for (i = (L_subfr >> 1); i != 0; i--) |
| { |
| tmp = *(p_y1++) >> 2; |
| s = amrnb_fxp_mac_16_by_16bb((Word32) tmp, (Word32) tmp, s); |
| tmp = *(p_y1++) >> 2; |
| s = amrnb_fxp_mac_16_by_16bb((Word32) tmp, (Word32) tmp, s); |
| } |
| |
| s <<= 1; |
| s += 1; /* Avoid case of all zeros */ |
| |
| exp_yy = norm_l(s); |
| L_temp = s << exp_yy; |
| yy = pv_round(L_temp, pOverflow); |
| exp_yy = exp_yy - 4; |
| |
| } |
| |
| /* Compute scalar product <xn[],y1[]> */ |
| |
| s = 0; |
| p_y1 = &y1[0]; |
| *pOverflow = 0; |
| |
| for (i = L_subfr; i != 0; i--) |
| { |
| L_temp = ((Word32) * (p_xn++) * *(p_y1++)); |
| s1 = s; |
| s = s1 + L_temp; |
| |
| if ((s1 ^ L_temp) > 0) |
| { |
| if ((s1 ^ s) < 0) |
| { |
| *pOverflow = 1; |
| break; |
| } |
| } |
| } |
| |
| if (!(*pOverflow)) |
| { |
| |
| s <<= 1; |
| s += 1; /* Avoid case of all zeros */ |
| |
| exp_xy = norm_l(s); /* Note 0<=exp_yy <= 31 */ |
| L_temp = s << exp_xy; |
| xy = pv_round(L_temp, pOverflow); |
| } |
| else |
| { |
| s = 0; /* re-initialize calculations */ |
| p_y1 = &y1[0]; |
| p_xn = &xn[0]; |
| for (i = (L_subfr >> 2); i != 0; i--) |
| { |
| L_temp = (Word32)(*(p_y1++) >> 2); |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_xn++), L_temp, s); |
| L_temp = (Word32)(*(p_y1++) >> 2); |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_xn++), L_temp, s); |
| L_temp = (Word32)(*(p_y1++) >> 2); |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_xn++), L_temp, s); |
| L_temp = (Word32)(*(p_y1++) >> 2); |
| s = amrnb_fxp_mac_16_by_16bb((Word32) * (p_xn++), L_temp, s); |
| } |
| |
| s <<= 1; |
| s += 1; /* Avoid case of all zeros */ |
| |
| exp_xy = norm_l(s); |
| L_temp = s << exp_xy; |
| xy = pv_round(L_temp, pOverflow); |
| exp_xy = exp_xy - 4; |
| |
| } |
| |
| g_coeff[0] = yy; |
| g_coeff[1] = 15 - exp_yy; |
| g_coeff[2] = xy; |
| g_coeff[3] = 15 - exp_xy; |
| |
| /* If (xy < 4) gain = 0 */ |
| if (xy < 4) |
| { |
| return ((Word16) 0); |
| } |
| |
| /* compute gain = xy/yy */ |
| /* Be sure xy < yy */ |
| |
| xy = xy >> 1; |
| |
| gain = div_s(xy, yy); |
| |
| i = exp_xy - exp_yy; /* Denormalization of division */ |
| |
| gain = shr(gain, i, pOverflow); |
| |
| |
| /* if(gain >1.2) gain = 1.2 */ |
| if (gain > 19661) |
| { |
| gain = 19661; |
| } |
| |
| if (mode == MR122) |
| { |
| /* clear 2 LSBits */ |
| gain = gain & 0xfffC; |
| } |
| |
| return(gain); |
| |
| } |
