Coverage Report

Created: 2025-07-11 06:40

/proc/self/cwd/libfaad/is.c
Line
Count
Source
1
/*
2
** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
3
** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com
4
**
5
** This program is free software; you can redistribute it and/or modify
6
** it under the terms of the GNU General Public License as published by
7
** the Free Software Foundation; either version 2 of the License, or
8
** (at your option) any later version.
9
**
10
** This program is distributed in the hope that it will be useful,
11
** but WITHOUT ANY WARRANTY; without even the implied warranty of
12
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13
** GNU General Public License for more details.
14
**
15
** You should have received a copy of the GNU General Public License
16
** along with this program; if not, write to the Free Software
17
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18
**
19
** Any non-GPL usage of this software or parts of this software is strictly
20
** forbidden.
21
**
22
** The "appropriate copyright message" mentioned in section 2c of the GPLv2
23
** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com"
24
**
25
** Commercial non-GPL licensing of this software is possible.
26
** For more info contact Nero AG through Mpeg4AAClicense@nero.com.
27
**
28
** $Id: is.c,v 1.28 2007/11/01 12:33:31 menno Exp $
29
**/
30
31
#include "common.h"
32
#include "structs.h"
33
34
#include "syntax.h"
35
#include "is.h"
36
37
#ifdef FIXED_POINT
38
static real_t pow05_table[] = {
39
    COEF_CONST(1.0),              /* 0.5^( 0/4) */
40
    COEF_CONST(0.84089641525371), /* 0.5^(+1/4) */
41
    COEF_CONST(0.70710678118655), /* 0.5^(+2/4) */
42
    COEF_CONST(0.59460355750136)  /* 0.5^(+3/4) */
43
};
44
#endif
45
46
void is_decode(ic_stream *ics, ic_stream *icsr, real_t *l_spec, real_t *r_spec,
47
               uint16_t frame_len)
48
63.9k
{
49
63.9k
    uint8_t g, sfb, b;
50
63.9k
    uint16_t i;
51
63.9k
    real_t scale;
52
#ifdef FIXED_POINT
53
    int32_t exp, frac;
54
#endif
55
56
63.9k
    uint16_t nshort = frame_len/8;
57
63.9k
    uint8_t group = 0;
58
59
199k
    for (g = 0; g < icsr->num_window_groups; g++)
60
135k
    {
61
        /* Do intensity stereo decoding */
62
287k
        for (b = 0; b < icsr->window_group_length[g]; b++)
63
151k
        {
64
334k
            for (sfb = 0; sfb < icsr->max_sfb; sfb++)
65
182k
            {
66
182k
                if (is_intensity(icsr, g, sfb))
67
21.5k
                {
68
21.5k
                    int16_t scale_factor = icsr->scale_factors[g][sfb];
69
#ifdef MAIN_DEC
70
                    /* For scalefactor bands coded in intensity stereo the
71
                       corresponding predictors in the right channel are
72
                       switched to "off".
73
                     */
74
                    ics->pred.prediction_used[sfb] = 0;
75
                    icsr->pred.prediction_used[sfb] = 0;
76
#endif
77
78
#ifndef FIXED_POINT
79
16.4k
                    scale_factor = min(max(scale_factor, -120), 120);
80
                    scale = (real_t)pow(0.5, (0.25*scale_factor));
81
#else
82
5.09k
                    scale_factor = min(max(scale_factor, -60), 60);
83
                    exp = scale_factor >> 2; /* exp is -15..15 */
84
                    frac = scale_factor & 3;
85
                    scale = pow05_table[frac];
86
5.09k
                    exp += COEF_BITS - REAL_BITS; /* exp is -1..29 */
87
5.09k
                    if (exp < 0)
88
672
                        scale <<= -exp;
89
4.41k
                    else
90
4.41k
                        scale >>= exp;
91
#endif
92
93
                    /* Scale from left to right channel,
94
                       do not touch left channel */
95
169k
                    for (i = icsr->swb_offset[sfb]; i < min(icsr->swb_offset[sfb+1], ics->swb_offset_max); i++)
96
148k
                    {
97
148k
                        r_spec[(group*nshort)+i] = MUL_R(l_spec[(group*nshort)+i], scale);
98
148k
                        if (is_intensity(icsr, g, sfb) != invert_intensity(ics, g, sfb))
99
53.3k
                            r_spec[(group*nshort)+i] = -r_spec[(group*nshort)+i];
100
148k
                    }
101
21.5k
                }
102
182k
            }
103
151k
            group++;
104
151k
        }
105
135k
    }
106
63.9k
}
is_decode
Line
Count
Source
48
21.3k
{
49
21.3k
    uint8_t g, sfb, b;
50
21.3k
    uint16_t i;
51
21.3k
    real_t scale;
52
21.3k
#ifdef FIXED_POINT
53
21.3k
    int32_t exp, frac;
54
21.3k
#endif
55
56
21.3k
    uint16_t nshort = frame_len/8;
57
21.3k
    uint8_t group = 0;
58
59
65.8k
    for (g = 0; g < icsr->num_window_groups; g++)
60
44.4k
    {
61
        /* Do intensity stereo decoding */
62
95.1k
        for (b = 0; b < icsr->window_group_length[g]; b++)
63
50.7k
        {
64
131k
            for (sfb = 0; sfb < icsr->max_sfb; sfb++)
65
80.3k
            {
66
80.3k
                if (is_intensity(icsr, g, sfb))
67
5.09k
                {
68
5.09k
                    int16_t scale_factor = icsr->scale_factors[g][sfb];
69
#ifdef MAIN_DEC
70
                    /* For scalefactor bands coded in intensity stereo the
71
                       corresponding predictors in the right channel are
72
                       switched to "off".
73
                     */
74
                    ics->pred.prediction_used[sfb] = 0;
75
                    icsr->pred.prediction_used[sfb] = 0;
76
#endif
77
78
#ifndef FIXED_POINT
79
                    scale_factor = min(max(scale_factor, -120), 120);
80
                    scale = (real_t)pow(0.5, (0.25*scale_factor));
81
#else
82
5.09k
                    scale_factor = min(max(scale_factor, -60), 60);
83
5.09k
                    exp = scale_factor >> 2; /* exp is -15..15 */
84
5.09k
                    frac = scale_factor & 3;
85
5.09k
                    scale = pow05_table[frac];
86
5.09k
                    exp += COEF_BITS - REAL_BITS; /* exp is -1..29 */
87
5.09k
                    if (exp < 0)
88
672
                        scale <<= -exp;
89
4.41k
                    else
90
4.41k
                        scale >>= exp;
91
5.09k
#endif
92
93
                    /* Scale from left to right channel,
94
                       do not touch left channel */
95
43.7k
                    for (i = icsr->swb_offset[sfb]; i < min(icsr->swb_offset[sfb+1], ics->swb_offset_max); i++)
96
38.6k
                    {
97
38.6k
                        r_spec[(group*nshort)+i] = MUL_R(l_spec[(group*nshort)+i], scale);
98
38.6k
                        if (is_intensity(icsr, g, sfb) != invert_intensity(ics, g, sfb))
99
22.2k
                            r_spec[(group*nshort)+i] = -r_spec[(group*nshort)+i];
100
38.6k
                    }
101
5.09k
                }
102
80.3k
            }
103
50.7k
            group++;
104
50.7k
        }
105
44.4k
    }
106
21.3k
}
is_decode
Line
Count
Source
48
42.5k
{
49
42.5k
    uint8_t g, sfb, b;
50
42.5k
    uint16_t i;
51
42.5k
    real_t scale;
52
#ifdef FIXED_POINT
53
    int32_t exp, frac;
54
#endif
55
56
42.5k
    uint16_t nshort = frame_len/8;
57
42.5k
    uint8_t group = 0;
58
59
133k
    for (g = 0; g < icsr->num_window_groups; g++)
60
91.1k
    {
61
        /* Do intensity stereo decoding */
62
192k
        for (b = 0; b < icsr->window_group_length[g]; b++)
63
101k
        {
64
203k
            for (sfb = 0; sfb < icsr->max_sfb; sfb++)
65
102k
            {
66
102k
                if (is_intensity(icsr, g, sfb))
67
16.4k
                {
68
16.4k
                    int16_t scale_factor = icsr->scale_factors[g][sfb];
69
16.4k
#ifdef MAIN_DEC
70
                    /* For scalefactor bands coded in intensity stereo the
71
                       corresponding predictors in the right channel are
72
                       switched to "off".
73
                     */
74
16.4k
                    ics->pred.prediction_used[sfb] = 0;
75
16.4k
                    icsr->pred.prediction_used[sfb] = 0;
76
16.4k
#endif
77
78
16.4k
#ifndef FIXED_POINT
79
16.4k
                    scale_factor = min(max(scale_factor, -120), 120);
80
16.4k
                    scale = (real_t)pow(0.5, (0.25*scale_factor));
81
#else
82
                    scale_factor = min(max(scale_factor, -60), 60);
83
                    exp = scale_factor >> 2; /* exp is -15..15 */
84
                    frac = scale_factor & 3;
85
                    scale = pow05_table[frac];
86
                    exp += COEF_BITS - REAL_BITS; /* exp is -1..29 */
87
                    if (exp < 0)
88
                        scale <<= -exp;
89
                    else
90
                        scale >>= exp;
91
#endif
92
93
                    /* Scale from left to right channel,
94
                       do not touch left channel */
95
126k
                    for (i = icsr->swb_offset[sfb]; i < min(icsr->swb_offset[sfb+1], ics->swb_offset_max); i++)
96
109k
                    {
97
109k
                        r_spec[(group*nshort)+i] = MUL_R(l_spec[(group*nshort)+i], scale);
98
109k
                        if (is_intensity(icsr, g, sfb) != invert_intensity(ics, g, sfb))
99
31.1k
                            r_spec[(group*nshort)+i] = -r_spec[(group*nshort)+i];
100
109k
                    }
101
16.4k
                }
102
102k
            }
103
101k
            group++;
104
101k
        }
105
91.1k
    }
106
42.5k
}