msamr/opencore-amr/opencore/codecs_v2/audio/gsm_amr/amr_nb/enc/src/spreproc.cpp
/* ------------------------------------------------------------------
* 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.
****************************************************************************************/
/*
------------------------------------------------------------------------------
Filename: spreproc.cpp
Functions: subframePreProc
------------------------------------------------------------------------------
MODULE DESCRIPTION
------------------------------------------------------------------------------
*/
/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/
#include "spreproc.h"
#include "typedef.h"
#include "weight_a.h"
#include "syn_filt.h"
#include "residu.h"
#include "oscl_mem.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: subframePreProc
------------------------------------------------------------------------------
INPUT AND OUTPUT DEFINITIONS
Inputs:
mode -- enum Mode -- coder mode
gamma1 -- const Word16 array -- spectral exp. factor 1
gamma1_12k2 -- const Word16 array -- spectral exp. factor 1 for EFR
gamma2 -- const Word16 array -- spectral exp. factor 2
A -- Pointer to Word16 -- A(z) unquantized for the 4 subframes
Aq -- Pointer to Word16 -- A(z) quantized for the 4 subframes
speech -- Pointer to Word16 -- speech segment
mem_err -- Pointer to Word16 -- pointer to error signal
mem_w0 -- Pointer to Word16 -- memory of weighting filter
zero -- Pointer to Word16 -- pointer to zero vector
Outputs:
ai_zero -- Word16 array -- history of weighted synth. filter
exc -- Word16 array -- long term prediction residual
h1 -- Word16 array -- impulse response
xn -- Word16 array -- target vector for pitch search
res2 -- Word16 array -- long term prediction residual
error -- Word16 array -- error of LPC synthesis filter
Returns:
Zero
Global Variables Used:
None
Local Variables Needed:
None
------------------------------------------------------------------------------
FUNCTION DESCRIPTION
------------------------------------------------------------------------------
REQUIREMENTS
None
------------------------------------------------------------------------------
REFERENCES
spreproc.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001
------------------------------------------------------------------------------
PSEUDO-CODE
------------------------------------------------------------------------------
CAUTION [optional]
[State any special notes, constraints or cautions for users of this function]
------------------------------------------------------------------------------
*/
void subframePreProc(
enum Mode mode, /* i : coder mode */
const Word16 gamma1[], /* i : spectral exp. factor 1 */
const Word16 gamma1_12k2[],/* i : spectral exp. factor 1 for EFR */
const Word16 gamma2[], /* i : spectral exp. factor 2 */
Word16 *A, /* i : A(z) unquantized for the 4 subframes */
Word16 *Aq, /* i : A(z) quantized for the 4 subframes */
Word16 *speech, /* i : speech segment */
Word16 *mem_err, /* i : pointer to error signal */
Word16 *mem_w0, /* i : memory of weighting filter */
Word16 *zero, /* i : pointer to zero vector */
Word16 ai_zero[], /* o : history of weighted synth. filter */
Word16 exc[], /* o : long term prediction residual */
Word16 h1[], /* o : impulse response */
Word16 xn[], /* o : target vector for pitch search */
Word16 res2[], /* o : long term prediction residual */
Word16 error[] /* o : error of LPC synthesis filter */
)
{
Word16 Ap1[MP1]; /* A(z) with spectral expansion */
Word16 Ap2[MP1]; /* A(z) with spectral expansion */
const Word16 *g1; /* Pointer to correct gammma1 vector */
/* mode specific pointer to gamma1 values */
if (mode == MR122 || mode == MR102)
{
g1 = gamma1_12k2;
}
else
{
g1 = gamma1;
}
/* Find the weighted LPC coefficients for the weighting filter. */
Weight_Ai(A, g1, Ap1);
Weight_Ai(A, gamma2, Ap2);
oscl_memcpy(ai_zero, Ap1, (M + 1)*sizeof(Word16));
Syn_filt(Aq, ai_zero, h1, L_SUBFR, zero, 0);
Syn_filt(Ap2, h1, h1, L_SUBFR, zero, 0);
/*
*
* Find the target vector for pitch search:
*
*/
/* LPC residual */
Residu(Aq, speech, res2, L_SUBFR);
oscl_memcpy(exc, res2, L_SUBFR*sizeof(Word16));
Syn_filt(Aq, exc, error, L_SUBFR, mem_err, 0);
Residu(Ap1, error, xn, L_SUBFR);
/* target signal xn[]*/
Syn_filt(Ap2, xn, xn, L_SUBFR, mem_w0, 0);
return;
}