ref: 0aa2ca7ee392ce54ca6273409165a3febb59e1a9
dir: /libfaad/sbr_qmf.c/
/*
** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
** Copyright (C) 2003 M. Bakker, Ahead Software AG, http://www.nero.com
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
** Any non-GPL usage of this software or parts of this software is strictly
** forbidden.
**
** Commercial non-GPL licensing of this software is possible.
** For more info contact Ahead Software through [email protected].
**
** $Id: sbr_qmf.c,v 1.6 2003/09/09 18:09:52 menno Exp $
**/
#include "common.h"
#include "structs.h"
#ifdef SBR_DEC
#include <stdlib.h>
#include <string.h>
#include "sbr_dct.h"
#include "sbr_qmf.h"
#include "sbr_syntax.h"
qmfa_info *qmfa_init(uint8_t channels)
{
qmfa_info *qmfa = (qmfa_info*)malloc(sizeof(qmfa_info));
qmfa->x = (real_t*)malloc(channels * 10 * sizeof(real_t));
memset(qmfa->x, 0, channels * 10 * sizeof(real_t));
qmfa->x_index = 0;
qmfa->channels = channels;
return qmfa;
}
void qmfa_end(qmfa_info *qmfa)
{
if (qmfa)
{
if (qmfa->x) free(qmfa->x);
free(qmfa);
}
}
void sbr_qmf_analysis_32(sbr_info *sbr, qmfa_info *qmfa, const real_t *input,
qmf_t *X, uint8_t offset)
{
uint8_t l;
real_t u[64];
#ifndef SBR_LOW_POWER
real_t x[64], y[64];
#else
real_t y[32];
#endif
const real_t *inptr = input;
/* qmf subsample l */
for (l = 0; l < sbr->numTimeSlotsRate; l++)
{
int16_t n;
/* shift input buffer x */
/* replaced by using qmfa->x_index */
/* add new samples to input buffer x */
for (n = 32 - 1; n >= 0; n--)
{
#ifdef FIXED_POINT
qmfa->x[(n + qmfa->x_index) & 319] = (*inptr++) >> 5; //5;
#else
qmfa->x[(n + qmfa->x_index) & 319] = *inptr++;
#endif
}
/* window and summation to create array u */
for (n = 0; n < 64; n++)
{
u[n] = MUL_R_C(qmfa->x[(n + qmfa->x_index) & 319], qmf_c_2[n]) +
MUL_R_C(qmfa->x[(n + 64 + qmfa->x_index) & 319], qmf_c_2[n + 64]) +
MUL_R_C(qmfa->x[(n + 128 + qmfa->x_index) & 319], qmf_c_2[n + 128]) +
MUL_R_C(qmfa->x[(n + 192 + qmfa->x_index) & 319], qmf_c_2[n + 192]) +
MUL_R_C(qmfa->x[(n + 256 + qmfa->x_index) & 319], qmf_c_2[n + 256]);
}
qmfa->x_index = (qmfa->x_index + 32) & 319;
/* calculate 32 subband samples by introducing X */
#ifdef SBR_LOW_POWER
y[0] = u[48];
for (n = 1; n < 16; n++)
y[n] = u[n+48] + u[48-n];
for (n = 16; n < 32; n++)
y[n] = -u[n-16] + u[48-n];
DCT3_32_unscaled(u, y);
for (n = 0; n < 32; n++)
{
#ifdef FIXED_POINT
QMF_RE(X[((l + offset)<<5) + n]) = u[n] << 1;
#else
QMF_RE(X[((l + offset)<<5) + n]) = 2. * u[n];
#endif
}
#else
x[0] = u[0];
x[63] = u[32];
for (n = 2; n < 64; n += 2)
{
x[n-1] = u[(n>>1)];
x[n] = -u[64-(n>>1)];
}
DCT4_64(y, x);
for (n = 0; n < 32; n++)
{
#ifdef FIXED_POINT
QMF_RE(X[((l + offset)<<5) + n]) = y[n] << 1;
QMF_IM(X[((l + offset)<<5) + n]) = -y[63-n] << 1;
#else
QMF_RE(X[((l + offset)<<5) + n]) = 2. * y[n];
QMF_IM(X[((l + offset)<<5) + n]) = -2. * y[63-n];
#endif
}
#endif
}
}
qmfs_info *qmfs_init(uint8_t channels)
{
int size = 0;
qmfs_info *qmfs = (qmfs_info*)malloc(sizeof(qmfs_info));
qmfs->v = (real_t*)malloc(channels * 20 * sizeof(real_t));
memset(qmfs->v, 0, channels * 20 * sizeof(real_t));
qmfs->v_index = 0;
qmfs->channels = channels;
return qmfs;
}
void qmfs_end(qmfs_info *qmfs)
{
if (qmfs)
{
if (qmfs->v) free(qmfs->v);
free(qmfs);
}
}
#ifdef SBR_LOW_POWER
void sbr_qmf_synthesis_64(sbr_info *sbr, qmfs_info *qmfs, const qmf_t *X,
real_t *output)
{
uint8_t l;
int16_t n, k;
real_t x[64];
real_t *outptr = output;
#ifndef FIXED_POINT
real_t scale = 1./32.;
#endif
/* qmf subsample l */
for (l = 0; l < sbr->numTimeSlotsRate; l++)
{
int16_t l64 = l<<6;
/* shift buffer */
/* replaced by using qmfs->v_index */
/* calculate 128 samples */
for (k = 0; k < 64; k++)
{
#ifdef FIXED_POINT
/* for fixed point the scaling is already done in the
* analysis filterbank */
x[k] = QMF_RE(X[l64 + k]);
#else
x[k] = scale * QMF_RE(X[l64 + k]);
#endif
}
DCT2_64_unscaled(x, x);
for (n = 0; n < 64; n++)
{
qmfs->v[(n + 32 + qmfs->v_index) & 1279] = x[n];
}
qmfs->v[0] = qmfs->v[64];
for (n = 1; n < 32; n++)
{
qmfs->v[(32 - n + qmfs->v_index) & 1279] = qmfs->v[(n + 32 + qmfs->v_index) & 1279];
qmfs->v[(n + 96 + qmfs->v_index) & 1279] = -qmfs->v[(96 - n + qmfs->v_index) & 1279];
}
/* calculate 64 output samples and window */
for (k = 0; k < 64; k++)
{
*outptr++ = MUL_R_C(qmfs->v[(k + qmfs->v_index) & 1279], qmf_c[k]) +
MUL_R_C(qmfs->v[(192 + k + qmfs->v_index) & 1279], qmf_c[64 + k]) +
MUL_R_C(qmfs->v[(256 + k + qmfs->v_index) & 1279], qmf_c[128 + k]) +
MUL_R_C(qmfs->v[(256 + 192 + k + qmfs->v_index) & 1279], qmf_c[128 + 64 + k]) +
MUL_R_C(qmfs->v[(512 + k + qmfs->v_index) & 1279], qmf_c[256 + k]) +
MUL_R_C(qmfs->v[(512 + 192 + k + qmfs->v_index) & 1279], qmf_c[256 + 64 + k]) +
MUL_R_C(qmfs->v[(768 + k + qmfs->v_index) & 1279], qmf_c[384 + k]) +
MUL_R_C(qmfs->v[(768 + 192 + k + qmfs->v_index) & 1279], qmf_c[384 + 64 + k]) +
MUL_R_C(qmfs->v[(1024 + k + qmfs->v_index) & 1279], qmf_c[512 + k]) +
MUL_R_C(qmfs->v[(1024 + 192 + k + qmfs->v_index) & 1279], qmf_c[512 + 64 + k]);
}
qmfs->v_index = (qmfs->v_index + 128) & 1279;
}
}
#else
void sbr_qmf_synthesis_64(sbr_info *sbr, qmfs_info *qmfs, const qmf_t *X,
real_t *output)
{
uint8_t l;
int16_t n, k;
real_t x1[64], x2[64];
real_t *outptr = output;
real_t scale = 1./64.;
/* qmf subsample l */
for (l = 0; l < sbr->numTimeSlotsRate; l++)
{
int16_t l64 = l << 6;
/* shift buffer */
/* replaced by using qmfs->v_index */
/* calculate 128 samples */
for (k = 0; k < 64; k++)
{
x1[k] = scale * QMF_RE(X[l64 + k]);
x2[k] = scale * QMF_IM(X[l64 + k]);
}
DCT4_64(x1, x1);
DST4_64(x2, x2);
for (n = 0; n < 64; n++)
{
qmfs->v[(n + qmfs->v_index) & 1279] = x2[n] - x1[n];
qmfs->v[(127 - n + qmfs->v_index) & 1279] = x2[n] + x1[n];
}
/* calculate 64 output samples and window */
for (k = 0; k < 64; k++)
{
*outptr++ =
MUL_R_C(qmfs->v[(k + qmfs->v_index) & 1279], qmf_c[k]) +
MUL_R_C(qmfs->v[(192 + k + qmfs->v_index) & 1279], qmf_c[64 + k]) +
MUL_R_C(qmfs->v[(256 + k + qmfs->v_index) & 1279], qmf_c[128 + k]) +
MUL_R_C(qmfs->v[(256 + 192 + k + qmfs->v_index) & 1279], qmf_c[128 + 64 + k]) +
MUL_R_C(qmfs->v[(512 + k + qmfs->v_index) & 1279], qmf_c[256 + k]) +
MUL_R_C(qmfs->v[(512 + 192 + k + qmfs->v_index) & 1279], qmf_c[256 + 64 + k]) +
MUL_R_C(qmfs->v[(768 + k + qmfs->v_index) & 1279], qmf_c[384 + k]) +
MUL_R_C(qmfs->v[(768 + 192 + k + qmfs->v_index) & 1279], qmf_c[384 + 64 + k]) +
MUL_R_C(qmfs->v[(1024 + k + qmfs->v_index) & 1279], qmf_c[512 + k]) +
MUL_R_C(qmfs->v[(1024 + 192 + k + qmfs->v_index) & 1279], qmf_c[512 + 64 + k]);
}
qmfs->v_index = (qmfs->v_index + 128) & 1279;
}
}
#endif
#endif