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/*
* downmix_c.c
*
* Copyright (C) Aaron Holtzman - May 1999
*
* This file is part of ac3dec, a free Dolby AC-3 stream decoder.
*
* ac3dec 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, or (at your option)
* any later version.
*
* ac3dec 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 GNU Make; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include "ac3.h"
#include "ac3_internal.h"
#include "debug.h"
#include "downmix.h"
#include "downmix_c.h"
void downmix_3f_2r_to_2ch_c (float *samples, dm_par_t *dm_par)
{
int i;
float *left, *right, *center, *left_sur, *right_sur;
float left_tmp, right_tmp;
left = samples;
right = samples + 256 * 2;
center = samples + 256;
left_sur = samples + 256 * 3;
right_sur = samples + 256 * 4;
for (i=0; i < 256; i++) {
#if defined DOLBY_SURROUND
left_tmp = dm_par->unit * *left + dm_par->clev * *center - dm_par->slev * (*left_sur + *right_sur);
right_tmp= dm_par->unit * *right++ + dm_par->clev * *center + dm_par->slev * (*left_sur++ + *right_sur++);
#else
left_tmp = dm_par->unit * *left + dm_par->clev * *center + dm_par->slev * *left_sur++;
right_tmp= dm_par->unit * *right++ + dm_par->clev * *center + dm_par->slev * *right_sur++;
#endif
*left++ = left_tmp;
*center++ = right_tmp;
}
}
void downmix_2f_2r_to_2ch_c (float *samples, dm_par_t *dm_par)
{
int i;
float *left, *right, *left_sur, *right_sur;
float left_tmp, right_tmp;
left = &samples[0];
right = &samples[256];
left_sur = &samples[512];
right_sur = &samples[768];
for (i = 0; i < 256; i++) {
left_tmp = dm_par->unit * *left + dm_par->slev * *left_sur++;
right_tmp= dm_par->unit * *right + dm_par->slev * *right_sur++;
*left++ = left_tmp;
*right++ = right_tmp;
}
}
void downmix_3f_1r_to_2ch_c (float *samples, dm_par_t *dm_par)
{
int i;
float *left, *right, *center, *right_sur;
float left_tmp, right_tmp;
left = &samples[0];
right = &samples[512];
center = &samples[256];
right_sur = &samples[768];
for (i = 0; i < 256; i++) {
left_tmp = dm_par->unit * *left + dm_par->clev * *center - dm_par->slev * *right_sur;
right_tmp= dm_par->unit * *right++ + dm_par->clev * *center + dm_par->slev * *right_sur++;
*left++ = left_tmp;
*center++ = right_tmp;
}
}
void downmix_2f_1r_to_2ch_c (float *samples, dm_par_t *dm_par)
{
int i;
float *left, *right, *right_sur;
float left_tmp, right_tmp;
left = &samples[0];
right = &samples[256];
right_sur = &samples[512];
for (i = 0; i < 256; i++) {
left_tmp = dm_par->unit * *left - dm_par->slev * *right_sur;
right_tmp= dm_par->unit * *right + dm_par->slev * *right_sur++;
*left++ = left_tmp;
*right++ = right_tmp;
}
}
void downmix_3f_0r_to_2ch_c (float *samples, dm_par_t *dm_par)
{
int i;
float *left, *right, *center;
float left_tmp, right_tmp;
left = &samples[0];
center = &samples[256];
right = &samples[512];
for (i = 0; i < 256; i++) {
left_tmp = dm_par->unit * *left + dm_par->clev * *center;
right_tmp= dm_par->unit * *right++ + dm_par->clev * *center;
*left++ = left_tmp;
*center++ = right_tmp;
}
}
void stream_sample_2ch_to_s16_c (int16_t *s16_samples, float *left, float *right)
{
int i;
for (i=0; i < 256; i++) {
*s16_samples++ = (int16_t) *left++;
*s16_samples++ = (int16_t) *right++;
}
}
void stream_sample_1ch_to_s16_c (int16_t *s16_samples, float *center)
{
int i;
float tmp;
for (i=0; i < 256; i++) {
*s16_samples++ = tmp = (int16_t) (0.7071f * *center++);
*s16_samples++ = tmp;
}
}
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