Coverage Report

Created: 2025-07-23 06:30

/proc/self/cwd/libfaad/is.c
Line
Count
Source
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/*
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** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
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** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com
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**
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** This program is free software; you can redistribute it and/or modify
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** it under the terms of the GNU General Public License as published by
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** the Free Software Foundation; either version 2 of the License, or
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** (at your option) any later version.
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**
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** This program is distributed in the hope that it will be useful,
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** but WITHOUT ANY WARRANTY; without even the implied warranty of
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** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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** GNU General Public License for more details.
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**
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** You should have received a copy of the GNU General Public License
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** along with this program; if not, write to the Free Software
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** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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**
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** Any non-GPL usage of this software or parts of this software is strictly
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** forbidden.
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**
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** The "appropriate copyright message" mentioned in section 2c of the GPLv2
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** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com"
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**
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** Commercial non-GPL licensing of this software is possible.
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** For more info contact Nero AG through Mpeg4AAClicense@nero.com.
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**
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** $Id: is.c,v 1.28 2007/11/01 12:33:31 menno Exp $
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**/
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#include "common.h"
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#include "structs.h"
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#include "syntax.h"
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#include "is.h"
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#ifdef FIXED_POINT
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static real_t pow05_table[] = {
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    COEF_CONST(1.0),              /* 0.5^( 0/4) */
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    COEF_CONST(0.84089641525371), /* 0.5^(+1/4) */
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    COEF_CONST(0.70710678118655), /* 0.5^(+2/4) */
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    COEF_CONST(0.59460355750136)  /* 0.5^(+3/4) */
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};
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#endif
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void is_decode(ic_stream *ics, ic_stream *icsr, real_t *l_spec, real_t *r_spec,
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               uint16_t frame_len)
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74.6k
{
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74.6k
    uint8_t g, sfb, b;
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74.6k
    uint16_t i;
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74.6k
    real_t scale;
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#ifdef FIXED_POINT
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    int32_t exp, frac;
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#endif
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56
74.6k
    uint16_t nshort = frame_len/8;
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74.6k
    uint8_t group = 0;
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59
232k
    for (g = 0; g < icsr->num_window_groups; g++)
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157k
    {
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        /* Do intensity stereo decoding */
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336k
        for (b = 0; b < icsr->window_group_length[g]; b++)
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178k
        {
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366k
            for (sfb = 0; sfb < icsr->max_sfb; sfb++)
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188k
            {
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188k
                if (is_intensity(icsr, g, sfb))
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24.3k
                {
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24.3k
                    int16_t scale_factor = icsr->scale_factors[g][sfb];
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#ifdef MAIN_DEC
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                    /* For scalefactor bands coded in intensity stereo the
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                       corresponding predictors in the right channel are
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                       switched to "off".
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                     */
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                    ics->pred.prediction_used[sfb] = 0;
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                    icsr->pred.prediction_used[sfb] = 0;
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#endif
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#ifndef FIXED_POINT
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17.2k
                    scale_factor = min(max(scale_factor, -120), 120);
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                    scale = (real_t)pow(0.5, (0.25*scale_factor));
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#else
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7.07k
                    scale_factor = min(max(scale_factor, -60), 60);
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                    exp = scale_factor >> 2; /* exp is -15..15 */
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                    frac = scale_factor & 3;
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                    scale = pow05_table[frac];
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7.07k
                    exp += COEF_BITS - REAL_BITS; /* exp is -1..29 */
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7.07k
                    if (exp < 0)
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742
                        scale <<= -exp;
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6.33k
                    else
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6.33k
                        scale >>= exp;
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#endif
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                    /* Scale from left to right channel,
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                       do not touch left channel */
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187k
                    for (i = icsr->swb_offset[sfb]; i < min(icsr->swb_offset[sfb+1], ics->swb_offset_max); i++)
96
163k
                    {
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163k
                        r_spec[(group*nshort)+i] = MUL_R(l_spec[(group*nshort)+i], scale);
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163k
                        if (is_intensity(icsr, g, sfb) != invert_intensity(ics, g, sfb))
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60.3k
                            r_spec[(group*nshort)+i] = -r_spec[(group*nshort)+i];
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163k
                    }
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24.3k
                }
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188k
            }
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178k
            group++;
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178k
        }
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157k
    }
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74.6k
}
is_decode
Line
Count
Source
48
30.3k
{
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30.3k
    uint8_t g, sfb, b;
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30.3k
    uint16_t i;
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30.3k
    real_t scale;
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30.3k
#ifdef FIXED_POINT
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30.3k
    int32_t exp, frac;
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30.3k
#endif
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56
30.3k
    uint16_t nshort = frame_len/8;
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30.3k
    uint8_t group = 0;
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59
95.7k
    for (g = 0; g < icsr->num_window_groups; g++)
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65.4k
    {
61
        /* Do intensity stereo decoding */
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141k
        for (b = 0; b < icsr->window_group_length[g]; b++)
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75.9k
        {
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164k
            for (sfb = 0; sfb < icsr->max_sfb; sfb++)
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88.7k
            {
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88.7k
                if (is_intensity(icsr, g, sfb))
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7.07k
                {
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7.07k
                    int16_t scale_factor = icsr->scale_factors[g][sfb];
69
#ifdef MAIN_DEC
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                    /* For scalefactor bands coded in intensity stereo the
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                       corresponding predictors in the right channel are
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                       switched to "off".
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                     */
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                    ics->pred.prediction_used[sfb] = 0;
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                    icsr->pred.prediction_used[sfb] = 0;
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#endif
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#ifndef FIXED_POINT
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                    scale_factor = min(max(scale_factor, -120), 120);
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                    scale = (real_t)pow(0.5, (0.25*scale_factor));
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#else
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7.07k
                    scale_factor = min(max(scale_factor, -60), 60);
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7.07k
                    exp = scale_factor >> 2; /* exp is -15..15 */
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7.07k
                    frac = scale_factor & 3;
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7.07k
                    scale = pow05_table[frac];
86
7.07k
                    exp += COEF_BITS - REAL_BITS; /* exp is -1..29 */
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7.07k
                    if (exp < 0)
88
742
                        scale <<= -exp;
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6.33k
                    else
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6.33k
                        scale >>= exp;
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7.07k
#endif
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                    /* Scale from left to right channel,
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                       do not touch left channel */
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57.3k
                    for (i = icsr->swb_offset[sfb]; i < min(icsr->swb_offset[sfb+1], ics->swb_offset_max); i++)
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50.2k
                    {
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50.2k
                        r_spec[(group*nshort)+i] = MUL_R(l_spec[(group*nshort)+i], scale);
98
50.2k
                        if (is_intensity(icsr, g, sfb) != invert_intensity(ics, g, sfb))
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30.7k
                            r_spec[(group*nshort)+i] = -r_spec[(group*nshort)+i];
100
50.2k
                    }
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7.07k
                }
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88.7k
            }
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75.9k
            group++;
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75.9k
        }
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65.4k
    }
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30.3k
}
is_decode
Line
Count
Source
48
44.3k
{
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44.3k
    uint8_t g, sfb, b;
50
44.3k
    uint16_t i;
51
44.3k
    real_t scale;
52
#ifdef FIXED_POINT
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    int32_t exp, frac;
54
#endif
55
56
44.3k
    uint16_t nshort = frame_len/8;
57
44.3k
    uint8_t group = 0;
58
59
136k
    for (g = 0; g < icsr->num_window_groups; g++)
60
92.3k
    {
61
        /* Do intensity stereo decoding */
62
195k
        for (b = 0; b < icsr->window_group_length[g]; b++)
63
102k
        {
64
202k
            for (sfb = 0; sfb < icsr->max_sfb; sfb++)
65
99.3k
            {
66
99.3k
                if (is_intensity(icsr, g, sfb))
67
17.2k
                {
68
17.2k
                    int16_t scale_factor = icsr->scale_factors[g][sfb];
69
17.2k
#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
                     */
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17.2k
                    ics->pred.prediction_used[sfb] = 0;
75
17.2k
                    icsr->pred.prediction_used[sfb] = 0;
76
17.2k
#endif
77
78
17.2k
#ifndef FIXED_POINT
79
17.2k
                    scale_factor = min(max(scale_factor, -120), 120);
80
17.2k
                    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
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                        scale >>= exp;
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#endif
92
93
                    /* Scale from left to right channel,
94
                       do not touch left channel */
95
130k
                    for (i = icsr->swb_offset[sfb]; i < min(icsr->swb_offset[sfb+1], ics->swb_offset_max); i++)
96
112k
                    {
97
112k
                        r_spec[(group*nshort)+i] = MUL_R(l_spec[(group*nshort)+i], scale);
98
112k
                        if (is_intensity(icsr, g, sfb) != invert_intensity(ics, g, sfb))
99
29.5k
                            r_spec[(group*nshort)+i] = -r_spec[(group*nshort)+i];
100
112k
                    }
101
17.2k
                }
102
99.3k
            }
103
102k
            group++;
104
102k
        }
105
92.3k
    }
106
44.3k
}