mirror of
https://github.com/mpv-player/mpv
synced 2024-11-18 21:16:10 +01:00
82361d50d0
Patch by me and Emanuele Giaquinta git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@18142 b3059339-0415-0410-9bf9-f77b7e298cf2
307 lines
10 KiB
C
307 lines
10 KiB
C
/*
|
|
** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
|
|
** Copyright (C) 2003-2004 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 Mpeg4AAClicense@nero.com.
|
|
**
|
|
** $Id: tns.c,v 1.35 2004/09/04 14:56:29 menno Exp $
|
|
**/
|
|
|
|
#include "common.h"
|
|
#include "structs.h"
|
|
|
|
#include "syntax.h"
|
|
#include "tns.h"
|
|
|
|
|
|
/* static function declarations */
|
|
static void tns_decode_coef(uint8_t order, uint8_t coef_res_bits, uint8_t coef_compress,
|
|
uint8_t *coef, real_t *a);
|
|
static void tns_ar_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc,
|
|
uint8_t order);
|
|
static void tns_ma_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc,
|
|
uint8_t order);
|
|
|
|
|
|
#ifdef _MSC_VER
|
|
#pragma warning(disable:4305)
|
|
#pragma warning(disable:4244)
|
|
#endif
|
|
static real_t tns_coef_0_3[] =
|
|
{
|
|
COEF_CONST(0.0), COEF_CONST(0.4338837391), COEF_CONST(0.7818314825), COEF_CONST(0.9749279122),
|
|
COEF_CONST(-0.9848077530), COEF_CONST(-0.8660254038), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433),
|
|
COEF_CONST(-0.4338837391), COEF_CONST(-0.7818314825), COEF_CONST(-0.9749279122), COEF_CONST(-0.9749279122),
|
|
COEF_CONST(-0.9848077530), COEF_CONST(-0.8660254038), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433)
|
|
};
|
|
static real_t tns_coef_0_4[] =
|
|
{
|
|
COEF_CONST(0.0), COEF_CONST(0.2079116908), COEF_CONST(0.4067366431), COEF_CONST(0.5877852523),
|
|
COEF_CONST(0.7431448255), COEF_CONST(0.8660254038), COEF_CONST(0.9510565163), COEF_CONST(0.9945218954),
|
|
COEF_CONST(-0.9957341763), COEF_CONST(-0.9618256432), COEF_CONST(-0.8951632914), COEF_CONST(-0.7980172273),
|
|
COEF_CONST(-0.6736956436), COEF_CONST(-0.5264321629), COEF_CONST(-0.3612416662), COEF_CONST(-0.1837495178)
|
|
};
|
|
static real_t tns_coef_1_3[] =
|
|
{
|
|
COEF_CONST(0.0), COEF_CONST(0.4338837391), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433),
|
|
COEF_CONST(0.9749279122), COEF_CONST(0.7818314825), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433),
|
|
COEF_CONST(-0.4338837391), COEF_CONST(-0.7818314825), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433),
|
|
COEF_CONST(-0.7818314825), COEF_CONST(-0.4338837391), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433)
|
|
};
|
|
static real_t tns_coef_1_4[] =
|
|
{
|
|
COEF_CONST(0.0), COEF_CONST(0.2079116908), COEF_CONST(0.4067366431), COEF_CONST(0.5877852523),
|
|
COEF_CONST(-0.6736956436), COEF_CONST(-0.5264321629), COEF_CONST(-0.3612416662), COEF_CONST(-0.1837495178),
|
|
COEF_CONST(0.9945218954), COEF_CONST(0.9510565163), COEF_CONST(0.8660254038), COEF_CONST(0.7431448255),
|
|
COEF_CONST(-0.6736956436), COEF_CONST(-0.5264321629), COEF_CONST(-0.3612416662), COEF_CONST(-0.1837495178)
|
|
};
|
|
|
|
|
|
/* TNS decoding for one channel and frame */
|
|
void tns_decode_frame(ic_stream *ics, tns_info *tns, uint8_t sr_index,
|
|
uint8_t object_type, real_t *spec, uint16_t frame_len)
|
|
{
|
|
uint8_t w, f, tns_order;
|
|
int8_t inc;
|
|
int16_t size;
|
|
uint16_t bottom, top, start, end;
|
|
uint16_t nshort = frame_len/8;
|
|
real_t lpc[TNS_MAX_ORDER+1];
|
|
|
|
if (!ics->tns_data_present)
|
|
return;
|
|
|
|
for (w = 0; w < ics->num_windows; w++)
|
|
{
|
|
bottom = ics->num_swb;
|
|
|
|
for (f = 0; f < tns->n_filt[w]; f++)
|
|
{
|
|
top = bottom;
|
|
bottom = max(top - tns->length[w][f], 0);
|
|
tns_order = min(tns->order[w][f], TNS_MAX_ORDER);
|
|
if (!tns_order)
|
|
continue;
|
|
|
|
tns_decode_coef(tns_order, tns->coef_res[w]+3,
|
|
tns->coef_compress[w][f], tns->coef[w][f], lpc);
|
|
|
|
start = min(bottom, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE)));
|
|
start = min(start, ics->max_sfb);
|
|
start = ics->swb_offset[start];
|
|
|
|
end = min(top, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE)));
|
|
end = min(end, ics->max_sfb);
|
|
end = ics->swb_offset[end];
|
|
|
|
size = end - start;
|
|
if (size <= 0)
|
|
continue;
|
|
|
|
if (tns->direction[w][f])
|
|
{
|
|
inc = -1;
|
|
start = end - 1;
|
|
} else {
|
|
inc = 1;
|
|
}
|
|
|
|
tns_ar_filter(&spec[(w*nshort)+start], size, inc, lpc, tns_order);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* TNS encoding for one channel and frame */
|
|
void tns_encode_frame(ic_stream *ics, tns_info *tns, uint8_t sr_index,
|
|
uint8_t object_type, real_t *spec, uint16_t frame_len)
|
|
{
|
|
uint8_t w, f, tns_order;
|
|
int8_t inc;
|
|
int16_t size;
|
|
uint16_t bottom, top, start, end;
|
|
uint16_t nshort = frame_len/8;
|
|
real_t lpc[TNS_MAX_ORDER+1];
|
|
|
|
if (!ics->tns_data_present)
|
|
return;
|
|
|
|
for (w = 0; w < ics->num_windows; w++)
|
|
{
|
|
bottom = ics->num_swb;
|
|
|
|
for (f = 0; f < tns->n_filt[w]; f++)
|
|
{
|
|
top = bottom;
|
|
bottom = max(top - tns->length[w][f], 0);
|
|
tns_order = min(tns->order[w][f], TNS_MAX_ORDER);
|
|
if (!tns_order)
|
|
continue;
|
|
|
|
tns_decode_coef(tns_order, tns->coef_res[w]+3,
|
|
tns->coef_compress[w][f], tns->coef[w][f], lpc);
|
|
|
|
start = min(bottom, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE)));
|
|
start = min(start, ics->max_sfb);
|
|
start = ics->swb_offset[start];
|
|
|
|
end = min(top, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE)));
|
|
end = min(end, ics->max_sfb);
|
|
end = ics->swb_offset[end];
|
|
|
|
size = end - start;
|
|
if (size <= 0)
|
|
continue;
|
|
|
|
if (tns->direction[w][f])
|
|
{
|
|
inc = -1;
|
|
start = end - 1;
|
|
} else {
|
|
inc = 1;
|
|
}
|
|
|
|
tns_ma_filter(&spec[(w*nshort)+start], size, inc, lpc, tns_order);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Decoder transmitted coefficients for one TNS filter */
|
|
static void tns_decode_coef(uint8_t order, uint8_t coef_res_bits, uint8_t coef_compress,
|
|
uint8_t *coef, real_t *a)
|
|
{
|
|
uint8_t i, m;
|
|
real_t tmp2[TNS_MAX_ORDER+1], b[TNS_MAX_ORDER+1];
|
|
|
|
/* Conversion to signed integer */
|
|
for (i = 0; i < order; i++)
|
|
{
|
|
if (coef_compress == 0)
|
|
{
|
|
if (coef_res_bits == 3)
|
|
{
|
|
tmp2[i] = tns_coef_0_3[coef[i]];
|
|
} else {
|
|
tmp2[i] = tns_coef_0_4[coef[i]];
|
|
}
|
|
} else {
|
|
if (coef_res_bits == 3)
|
|
{
|
|
tmp2[i] = tns_coef_1_3[coef[i]];
|
|
} else {
|
|
tmp2[i] = tns_coef_1_4[coef[i]];
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Conversion to LPC coefficients */
|
|
a[0] = COEF_CONST(1.0);
|
|
for (m = 1; m <= order; m++)
|
|
{
|
|
for (i = 1; i < m; i++) /* loop only while i<m */
|
|
b[i] = a[i] + MUL_C(tmp2[m-1], a[m-i]);
|
|
|
|
for (i = 1; i < m; i++) /* loop only while i<m */
|
|
a[i] = b[i];
|
|
|
|
a[m] = tmp2[m-1]; /* changed */
|
|
}
|
|
}
|
|
|
|
static void tns_ar_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc,
|
|
uint8_t order)
|
|
{
|
|
/*
|
|
- Simple all-pole filter of order "order" defined by
|
|
y(n) = x(n) - lpc[1]*y(n-1) - ... - lpc[order]*y(n-order)
|
|
- The state variables of the filter are initialized to zero every time
|
|
- The output data is written over the input data ("in-place operation")
|
|
- An input vector of "size" samples is processed and the index increment
|
|
to the next data sample is given by "inc"
|
|
*/
|
|
|
|
uint8_t j;
|
|
uint16_t i;
|
|
real_t y;
|
|
/* state is stored as a double ringbuffer */
|
|
real_t state[2*TNS_MAX_ORDER] = {0};
|
|
int8_t state_index = 0;
|
|
|
|
for (i = 0; i < size; i++)
|
|
{
|
|
y = *spectrum;
|
|
|
|
for (j = 0; j < order; j++)
|
|
y -= MUL_C(state[state_index+j], lpc[j+1]);
|
|
|
|
/* double ringbuffer state */
|
|
state_index--;
|
|
if (state_index < 0)
|
|
state_index = order-1;
|
|
state[state_index] = state[state_index + order] = y;
|
|
|
|
*spectrum = y;
|
|
spectrum += inc;
|
|
|
|
//#define TNS_PRINT
|
|
#ifdef TNS_PRINT
|
|
//printf("%d\n", y);
|
|
printf("0x%.8X\n", y);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
static void tns_ma_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc,
|
|
uint8_t order)
|
|
{
|
|
/*
|
|
- Simple all-zero filter of order "order" defined by
|
|
y(n) = x(n) + a(2)*x(n-1) + ... + a(order+1)*x(n-order)
|
|
- The state variables of the filter are initialized to zero every time
|
|
- The output data is written over the input data ("in-place operation")
|
|
- An input vector of "size" samples is processed and the index increment
|
|
to the next data sample is given by "inc"
|
|
*/
|
|
|
|
uint8_t j;
|
|
uint16_t i;
|
|
real_t y;
|
|
/* state is stored as a double ringbuffer */
|
|
real_t state[2*TNS_MAX_ORDER] = {0};
|
|
int8_t state_index = 0;
|
|
|
|
for (i = 0; i < size; i++)
|
|
{
|
|
y = *spectrum;
|
|
|
|
for (j = 0; j < order; j++)
|
|
y += MUL_C(state[j], lpc[j+1]);
|
|
|
|
/* double ringbuffer state */
|
|
state_index--;
|
|
if (state_index < 0)
|
|
state_index = order-1;
|
|
state[state_index] = state[state_index + order] = *spectrum;
|
|
|
|
*spectrum = y;
|
|
spectrum += inc;
|
|
}
|
|
}
|