/* ------------------------------------------------------------------ * 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/pre_proc.c Funtions: Pre_Process_init Pre_Process_reset Pre_Process_exit Pre_Process Date: 05/17/2000 ------------------------------------------------------------------------------ REVISION HISTORY Description: Put the file into our template structure. Description: First pass optimization. Description: Made changes based on comments from review meeting. Description: Synchronized file with UMTS version 3.2.0. Updated coding template. Removed unnecessary include files. Description: Removed basic_op.h from the Include section. It is not used. Description: Made the following changes per comments from Phase 2/3 review: 1. Fixed typecasting issue with TI C compiler. 2. Modified FOR loop to count down. 3. Cosmetic changes to the code to make address post-increment clearer. 4. Removed unnecessary typecasting in the multiply-accumulate portion of FOR loop body. 5. Removed "static" in table definitions. 6. Updated copyright year. Description: For Pre_Process() 1. Replaced variables (containing filter coefficients) with constants, to avoid extra register swaping. 2. Changed to decrement loop 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: ------------------------------------------------------------------------------ MODULE DESCRIPTION These modules handle the preprocessing of input speech. ------------------------------------------------------------------------------ */ /*---------------------------------------------------------------------------- ; INCLUDES ----------------------------------------------------------------------------*/ #include #include "pre_proc.h" #include "typedef.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 VARIABLE DEFINITIONS ; Variable declaration - defined here and used outside this module ----------------------------------------------------------------------------*/ /* ------------------------------------------------------------------------------ FUNCTION NAME: Pre_Process_init ------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS Inputs: state = pointer to an array of pointer to structures of type Pre_ProcessState Outputs: Structure pointed to by the pointer pointed to by state is initialized to its reset value state points to the allocated memory Returns: return_value = 0 if memory was successfully initialized, otherwise returns -1. Global Variables Used: None. Local Variables Needed: None. ------------------------------------------------------------------------------ FUNCTION DESCRIPTION Allocates state memory and initializes state memory. ------------------------------------------------------------------------------ REQUIREMENTS None. ------------------------------------------------------------------------------ REFERENCES pre_proc.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 ------------------------------------------------------------------------------ PSEUDO-CODE int Pre_Process_init (Pre_ProcessState **state) { Pre_ProcessState* s; if (state == (Pre_ProcessState **) NULL){ fprintf(stderr, "Pre_Process_init: invalid parameter\n"); return -1; } *state = NULL; // allocate memory if ((s= (Pre_ProcessState *) malloc(sizeof(Pre_ProcessState))) == NULL){ fprintf(stderr, "Pre_Process_init: can not malloc state structure\n"); return -1; } Pre_Process_reset(s); *state = s; return 0; } ------------------------------------------------------------------------------ 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 Pre_Process_init(Pre_ProcessState **state) { Pre_ProcessState* s; if (state == (Pre_ProcessState **) NULL) { /* fprintf(stderr, "Pre_Process_init: invalid parameter\n"); */ return(-1); } *state = NULL; /* allocate memory */ if ((s = (Pre_ProcessState *) malloc(sizeof(Pre_ProcessState))) == NULL) { /* fprintf(stderr, "Pre_Process_init: can not malloc state structure\n"); */ return(-1); } Pre_Process_reset(s); *state = s; return(0); } /****************************************************************************/ /* ------------------------------------------------------------------------------ FUNCTION NAME: Pre_Process_reset ------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS Inputs: state = pointer to structure of type Pre_ProcessState Outputs: Structure pointed to by state is initialized to zero. Returns: return_value = 0 if memory was successfully reset, otherwise returns -1. Global Variables Used: None. Local Variables Needed: None. ------------------------------------------------------------------------------ FUNCTION DESCRIPTION Initializes state memory to zero. ------------------------------------------------------------------------------ REQUIREMENTS None. ------------------------------------------------------------------------------ REFERENCES pre_proc.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 ------------------------------------------------------------------------------ PSEUDO-CODE int Pre_Process_reset (Pre_ProcessState *state) { if (state == (Pre_ProcessState *) NULL){ fprintf(stderr, "Pre_Process_reset: invalid parameter\n"); return -1; } state->y2_hi = 0; state->y2_lo = 0; state->y1_hi = 0; state->y1_lo = 0; state->x0 = 0; state->x1 = 0; return 0; } ------------------------------------------------------------------------------ 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 Pre_Process_reset(Pre_ProcessState *state) { if (state == (Pre_ProcessState *) NULL) { /* fprintf(stderr, "Pre_Process_reset: invalid parameter\n"); */ return(-1); } state->y2_hi = 0; state->y2_lo = 0; state->y1_hi = 0; state->y1_lo = 0; state->x0 = 0; state->x1 = 0; return(0); } /****************************************************************************/ /* ------------------------------------------------------------------------------ FUNCTION NAME: Pre_Process_exit ------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS Inputs: state = a pointer to an array of pointers to structures of type Pre_ProcessState Outputs: state points to a NULL address Returns: None. Global Variables Used: None. Local Variables Needed: None. ------------------------------------------------------------------------------ FUNCTION DESCRIPTION The memory used for state memory is freed. ------------------------------------------------------------------------------ REQUIREMENTS None. ------------------------------------------------------------------------------ REFERENCES pre_proc.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 ------------------------------------------------------------------------------ PSEUDO-CODE void Pre_Process_exit (Pre_ProcessState **state) { if (state == NULL || *state == NULL) return; // deallocate memory free(*state); *state = NULL; return; } ------------------------------------------------------------------------------ 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 Pre_Process_exit(Pre_ProcessState **state) { if (state == NULL || *state == NULL) { return; } /* deallocate memory */ free(*state); *state = NULL; return; } /****************************************************************************/ /* ------------------------------------------------------------------------------ FUNCTION NAME: Pre_Process ------------------------------------------------------------------------------ INPUT AND OUTPUT DEFINITIONS Inputs: st = a pointer to a structure of type Pre_ProcessState signal = input/output signal (Word16) lg = length of signal (Word16) Outputs: st points to the updated structure Returns: return_value = 0 (int) Global Variables Used: a = points to a buffer of filter coefficients b = points to a buffer of filter coefficients Local Variables Needed: None. ------------------------------------------------------------------------------ FUNCTION DESCRIPTION This module performs the preprocessing of the input speech. The signal is passed through a 2nd order high pass filtering with cut off frequency at 80 Hz. The input is divided by two in the filtering process. y[i] = b[0]*x[i]/2 + b[1]*x[i-1]/2 + b[2]*x[i-2]/2 + a[1]*y[i-1] + a[2]*y[i-2]; ------------------------------------------------------------------------------ REQUIREMENTS None. ------------------------------------------------------------------------------ REFERENCES pre_proc.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 ------------------------------------------------------------------------------ PSEUDO-CODE int Pre_Process ( Pre_ProcessState *st, Word16 signal[], // input/output signal Word16 lg) // lenght of signal { Word16 i, x2; Word32 L_tmp; for (i = 0; i < lg; i++) { x2 = st->x1; st->x1 = st->x0; st->x0 = signal[i]; // y[i] = b[0]*x[i]/2 + b[1]*x[i-1]/2 + b140[2]*x[i-2]/2 // + a[1]*y[i-1] + a[2] * y[i-2]; L_tmp = Mpy_32_16 (st->y1_hi, st->y1_lo, a[1]); L_tmp = L_add (L_tmp, Mpy_32_16 (st->y2_hi, st->y2_lo, a[2])); L_tmp = L_mac (L_tmp, st->x0, b[0]); L_tmp = L_mac (L_tmp, st->x1, b[1]); L_tmp = L_mac (L_tmp, x2, b[2]); L_tmp = L_shl (L_tmp, 3); signal[i] = pv_round (L_tmp); st->y2_hi = st->y1_hi; st->y2_lo = st->y1_lo; L_Extract (L_tmp, &st->y1_hi, &st->y1_lo); } return 0; } ------------------------------------------------------------------------------ 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] ------------------------------------------------------------------------------ */ /* filter coefficients (fc = 80 Hz, coeff. b[] is divided by 2) const Word16 b[3] = {1899, -3798, 1899}; const Word16 a[3] = {4096, 7807, -3733}; */ void Pre_Process( Pre_ProcessState *st, Word16 signal[], /* input/output signal */ Word16 lg) /* length of signal */ { Word16 i; Word16 x_n_2; Word16 x_n_1; Word32 L_tmp; Word16 *p_signal = signal; x_n_2 = st->x1; x_n_1 = st->x0; for (i = lg; i != 0; i--) { /* y[i] = b[0]*x[i]/2 + b[1]*x[i-1]/2 + b140[2]*x[i-2]/2 */ /* + a[1]*y[i-1] + a[2] * y[i-2]; */ L_tmp = ((Word32) st->y1_hi) * 7807; L_tmp += (Word32)(((Word32) st->y1_lo * 7807) >> 15); L_tmp += ((Word32) st->y2_hi) * (-3733); st->y2_hi = st->y1_hi; L_tmp += (Word32)(((Word32) st->y2_lo * (-3733)) >> 15); st->y2_lo = st->y1_lo; L_tmp += ((Word32) x_n_2) * 1899; x_n_2 = x_n_1; L_tmp += ((Word32) x_n_1) * (-3798); x_n_1 = *(p_signal); L_tmp += ((Word32) x_n_1) * 1899; *(p_signal++) = (Word16)((L_tmp + 0x0000800L) >> 12); st->y1_hi = (Word16)(L_tmp >> 12); __builtin_sub_overflow((Word16)(L_tmp << 3), (st->y1_hi) << 15, &st->y1_lo); } st->x1 = x_n_2; st->x0 = x_n_1; return; }