Coverage Report

Created: 2025-07-18 06:36

/proc/self/cwd/libfaad/pns.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: pns.c,v 1.39 2010/06/04 20:47:56 menno Exp $
29
**/
30
31
#include "common.h"
32
#include "structs.h"
33
34
#include "pns.h"
35
36
37
/* static function declarations */
38
static void gen_rand_vector(real_t *spec, int16_t scale_factor, uint16_t size,
39
                            uint8_t sub,
40
                            /* RNG states */ uint32_t *__r1, uint32_t *__r2);
41
42
43
#ifdef FIXED_POINT
44
45
static real_t const pow2_table[] =
46
{
47
    COEF_CONST(1.0),
48
    COEF_CONST(1.18920711500272),
49
    COEF_CONST(1.41421356237310),
50
    COEF_CONST(1.68179283050743)
51
};
52
53
// mean_energy_table[x] == sqrt(3 / x)
54
static real_t const mean_energy_table[] =
55
{
56
    COEF_CONST(0.0),                // should not happen
57
    COEF_CONST(1.7320508075688772),
58
    COEF_CONST(1.224744871391589),
59
    COEF_CONST(1.0),                // sqrt(3/3)
60
    COEF_CONST(0.8660254037844386),
61
    COEF_CONST(0.7745966692414834),
62
    COEF_CONST(0.7071067811865476),
63
    COEF_CONST(0.6546536707079771),
64
    COEF_CONST(0.6123724356957945),
65
    COEF_CONST(0.5773502691896257),
66
    COEF_CONST(0.5477225575051661),
67
    COEF_CONST(0.5222329678670935),
68
    COEF_CONST(0.5),                // sqrt(3/12)
69
    COEF_CONST(0.4803844614152614),
70
    COEF_CONST(0.4629100498862757),
71
    COEF_CONST(0.4472135954999579),
72
};
73
#endif
74
75
/* The function gen_rand_vector(addr, size) generates a vector of length
76
   <size> with signed random values of average energy MEAN_NRG per random
77
   value. A suitable random number generator can be realized using one
78
   multiplication/accumulation per random value.
79
*/
80
static INLINE void gen_rand_vector(real_t *spec, int16_t scale_factor, uint16_t size,
81
                                   uint8_t sub,
82
                                   /* RNG states */ uint32_t *__r1, uint32_t *__r2)
83
85.0k
{
84
#ifndef FIXED_POINT
85
    uint16_t i;
86
    real_t energy = 0.0;
87
    (void)sub;
88
89
38.6k
    scale_factor = min(max(scale_factor, -120), 120);
90
91
365k
    for (i = 0; i < size; i++)
92
326k
    {
93
326k
        real_t tmp = (real_t)(int32_t)ne_rng(__r1, __r2);
94
326k
        spec[i] = tmp;
95
326k
        energy += tmp*tmp;
96
326k
    }
97
98
38.6k
    if (energy > 0)
99
16.8k
    {
100
16.8k
        real_t scale = (real_t)1.0/(real_t)sqrt(energy);
101
16.8k
        scale *= (real_t)pow(2.0, 0.25 * scale_factor);
102
343k
        for (i = 0; i < size; i++)
103
326k
        {
104
326k
            spec[i] *= scale;
105
326k
        }
106
16.8k
    }
107
#else
108
    uint16_t i;
109
    real_t scale;
110
    int32_t exp, frac;
111
    int32_t idx, mask;
112
113
    /* IMDCT pre-scaling */
114
    scale_factor -= 4 * sub;
115
116
    // 52 stands for 2**13 == 8192 factor; larger factor causes overflows later (in cfft).
117
46.4k
    scale_factor = min(max(scale_factor, -(REAL_BITS * 4)), 52);
118
119
    exp = scale_factor >> 2;
120
    frac = scale_factor & 3;
121
122
    /* 29 <= REAL_BITS + exp <= 0 */
123
46.4k
    mask = (1 << (REAL_BITS + exp)) - 1;
124
125
    idx = size;
126
46.4k
    scale = COEF_CONST(1);
127
    // At most 2 iterations.
128
52.9k
    while (idx >= 16)
129
6.45k
    {
130
6.45k
        idx >>= 2;
131
6.45k
        scale >>= 1;
132
6.45k
    }
133
46.4k
    scale = MUL_C(scale, mean_energy_table[idx]);
134
46.4k
    if (frac)
135
8.40k
        scale = MUL_C(scale, pow2_table[frac]);
136
    // scale is less than 4.0 now.
137
138
466k
    for (i = 0; i < size; i++)
139
419k
    {
140
419k
        real_t tmp = (int32_t)ne_rng(__r1, __r2);
141
419k
        if (tmp < 0)
142
212k
            tmp = -(tmp & mask);
143
207k
        else
144
207k
            tmp = (tmp & mask);
145
419k
        spec[i] = MUL_C(tmp, scale);
146
419k
    }
147
#endif
148
85.0k
}
pns.c:gen_rand_vector
Line
Count
Source
83
46.4k
{
84
#ifndef FIXED_POINT
85
    uint16_t i;
86
    real_t energy = 0.0;
87
    (void)sub;
88
89
    scale_factor = min(max(scale_factor, -120), 120);
90
91
    for (i = 0; i < size; i++)
92
    {
93
        real_t tmp = (real_t)(int32_t)ne_rng(__r1, __r2);
94
        spec[i] = tmp;
95
        energy += tmp*tmp;
96
    }
97
98
    if (energy > 0)
99
    {
100
        real_t scale = (real_t)1.0/(real_t)sqrt(energy);
101
        scale *= (real_t)pow(2.0, 0.25 * scale_factor);
102
        for (i = 0; i < size; i++)
103
        {
104
            spec[i] *= scale;
105
        }
106
    }
107
#else
108
46.4k
    uint16_t i;
109
46.4k
    real_t scale;
110
46.4k
    int32_t exp, frac;
111
46.4k
    int32_t idx, mask;
112
113
    /* IMDCT pre-scaling */
114
46.4k
    scale_factor -= 4 * sub;
115
116
    // 52 stands for 2**13 == 8192 factor; larger factor causes overflows later (in cfft).
117
46.4k
    scale_factor = min(max(scale_factor, -(REAL_BITS * 4)), 52);
118
119
46.4k
    exp = scale_factor >> 2;
120
46.4k
    frac = scale_factor & 3;
121
122
    /* 29 <= REAL_BITS + exp <= 0 */
123
46.4k
    mask = (1 << (REAL_BITS + exp)) - 1;
124
125
46.4k
    idx = size;
126
46.4k
    scale = COEF_CONST(1);
127
    // At most 2 iterations.
128
52.9k
    while (idx >= 16)
129
6.45k
    {
130
6.45k
        idx >>= 2;
131
6.45k
        scale >>= 1;
132
6.45k
    }
133
46.4k
    scale = MUL_C(scale, mean_energy_table[idx]);
134
46.4k
    if (frac)
135
8.40k
        scale = MUL_C(scale, pow2_table[frac]);
136
    // scale is less than 4.0 now.
137
138
466k
    for (i = 0; i < size; i++)
139
419k
    {
140
419k
        real_t tmp = (int32_t)ne_rng(__r1, __r2);
141
419k
        if (tmp < 0)
142
212k
            tmp = -(tmp & mask);
143
207k
        else
144
207k
            tmp = (tmp & mask);
145
419k
        spec[i] = MUL_C(tmp, scale);
146
419k
    }
147
46.4k
#endif
148
46.4k
}
pns.c:gen_rand_vector
Line
Count
Source
83
38.6k
{
84
38.6k
#ifndef FIXED_POINT
85
38.6k
    uint16_t i;
86
38.6k
    real_t energy = 0.0;
87
38.6k
    (void)sub;
88
89
38.6k
    scale_factor = min(max(scale_factor, -120), 120);
90
91
365k
    for (i = 0; i < size; i++)
92
326k
    {
93
326k
        real_t tmp = (real_t)(int32_t)ne_rng(__r1, __r2);
94
326k
        spec[i] = tmp;
95
326k
        energy += tmp*tmp;
96
326k
    }
97
98
38.6k
    if (energy > 0)
99
16.8k
    {
100
16.8k
        real_t scale = (real_t)1.0/(real_t)sqrt(energy);
101
16.8k
        scale *= (real_t)pow(2.0, 0.25 * scale_factor);
102
343k
        for (i = 0; i < size; i++)
103
326k
        {
104
326k
            spec[i] *= scale;
105
326k
        }
106
16.8k
    }
107
#else
108
    uint16_t i;
109
    real_t scale;
110
    int32_t exp, frac;
111
    int32_t idx, mask;
112
113
    /* IMDCT pre-scaling */
114
    scale_factor -= 4 * sub;
115
116
    // 52 stands for 2**13 == 8192 factor; larger factor causes overflows later (in cfft).
117
    scale_factor = min(max(scale_factor, -(REAL_BITS * 4)), 52);
118
119
    exp = scale_factor >> 2;
120
    frac = scale_factor & 3;
121
122
    /* 29 <= REAL_BITS + exp <= 0 */
123
    mask = (1 << (REAL_BITS + exp)) - 1;
124
125
    idx = size;
126
    scale = COEF_CONST(1);
127
    // At most 2 iterations.
128
    while (idx >= 16)
129
    {
130
        idx >>= 2;
131
        scale >>= 1;
132
    }
133
    scale = MUL_C(scale, mean_energy_table[idx]);
134
    if (frac)
135
        scale = MUL_C(scale, pow2_table[frac]);
136
    // scale is less than 4.0 now.
137
138
    for (i = 0; i < size; i++)
139
    {
140
        real_t tmp = (int32_t)ne_rng(__r1, __r2);
141
        if (tmp < 0)
142
            tmp = -(tmp & mask);
143
        else
144
            tmp = (tmp & mask);
145
        spec[i] = MUL_C(tmp, scale);
146
    }
147
#endif
148
38.6k
}
149
150
void pns_decode(ic_stream *ics_left, ic_stream *ics_right,
151
                real_t *spec_left, real_t *spec_right, uint16_t frame_len,
152
                uint8_t channel_pair, uint8_t object_type,
153
                /* RNG states */ uint32_t *__r1, uint32_t *__r2)
154
656k
{
155
656k
    uint8_t g, sfb, b;
156
656k
    uint16_t begin, end;
157
158
656k
    uint8_t group = 0;
159
656k
    uint16_t nshort = frame_len >> 3;
160
161
656k
    uint8_t sub = 0;
162
163
#ifdef FIXED_POINT
164
    /* IMDCT scaling */
165
282k
    if (object_type == LD)
166
1.21k
    {
167
1.21k
        sub = 9 /*9*/;
168
280k
    } else {
169
280k
        if (ics_left->window_sequence == EIGHT_SHORT_SEQUENCE)
170
23.3k
            sub = 7 /*7*/;
171
257k
        else
172
257k
            sub = 10 /*10*/;
173
280k
    }
174
#else
175
    (void)object_type;
176
#endif
177
178
1.64M
    for (g = 0; g < ics_left->num_window_groups; g++)
179
985k
    {
180
        /* Do perceptual noise substitution decoding */
181
2.04M
        for (b = 0; b < ics_left->window_group_length[g]; b++)
182
1.05M
        {
183
1.05M
            uint16_t base = group * nshort;
184
1.47M
            for (sfb = 0; sfb < ics_left->max_sfb; sfb++)
185
414k
            {
186
414k
                uint32_t r1_dep = 0, r2_dep = 0;
187
188
414k
                if (is_noise(ics_left, g, sfb))
189
55.8k
                {
190
#ifdef LTP_DEC
191
                    /* Simultaneous use of LTP and PNS is not prevented in the
192
                       syntax. If both LTP, and PNS are enabled on the same
193
                       scalefactor band, PNS takes precedence, and no prediction
194
                       is applied to this band.
195
                    */
196
                    ics_left->ltp.long_used[sfb] = 0;
197
                    ics_left->ltp2.long_used[sfb] = 0;
198
#endif
199
200
#ifdef MAIN_DEC
201
                    /* For scalefactor bands coded using PNS the corresponding
202
                       predictors are switched to "off".
203
                    */
204
                    ics_left->pred.prediction_used[sfb] = 0;
205
#endif
206
55.8k
                    begin = min(base + ics_left->swb_offset[sfb], ics_left->swb_offset_max);
207
55.8k
                    end = min(base + ics_left->swb_offset[sfb+1], ics_left->swb_offset_max);
208
209
55.8k
                    r1_dep = *__r1;
210
55.8k
                    r2_dep = *__r2;
211
212
                    /* Generate random vector */
213
55.8k
                    gen_rand_vector(&spec_left[begin],
214
55.8k
                        ics_left->scale_factors[g][sfb], end - begin, sub, __r1, __r2);
215
55.8k
                }
216
217
/* From the spec:
218
   If the same scalefactor band and group is coded by perceptual noise
219
   substitution in both channels of a channel pair, the correlation of
220
   the noise signal can be controlled by means of the ms_used field: While
221
   the default noise generation process works independently for each channel
222
   (separate generation of random vectors), the same random vector is used
223
   for both channels if ms_used[] is set for a particular scalefactor band
224
   and group. In this case, no M/S stereo coding is carried out (because M/S
225
   stereo coding and noise substitution coding are mutually exclusive).
226
   If the same scalefactor band and group is coded by perceptual noise
227
   substitution in only one channel of a channel pair the setting of ms_used[]
228
   is not evaluated.
229
*/
230
414k
                if ((ics_right != NULL)
231
414k
                    && is_noise(ics_right, g, sfb))
232
29.2k
                {
233
#ifdef LTP_DEC
234
                    /* See comment above. */
235
                    ics_right->ltp.long_used[sfb] = 0;
236
                    ics_right->ltp2.long_used[sfb] = 0;
237
#endif
238
#ifdef MAIN_DEC
239
                    /* See comment above. */
240
                    ics_right->pred.prediction_used[sfb] = 0;
241
#endif
242
243
29.2k
                    if (channel_pair && is_noise(ics_left, g, sfb) &&
244
29.2k
                        (((ics_left->ms_mask_present == 1) &&
245
12.3k
                        (ics_left->ms_used[g][sfb])) ||
246
12.3k
                        (ics_left->ms_mask_present == 2)))
247
7.41k
                    {
248
                        /*uint16_t c;*/
249
250
7.41k
                        begin = min(base + ics_right->swb_offset[sfb], ics_right->swb_offset_max);
251
7.41k
                        end = min(base + ics_right->swb_offset[sfb+1], ics_right->swb_offset_max);
252
253
                        /* Generate random vector dependent on left channel*/
254
7.41k
                        gen_rand_vector(&spec_right[begin],
255
7.41k
                            ics_right->scale_factors[g][sfb], end - begin, sub, &r1_dep, &r2_dep);
256
257
21.8k
                    } else /*if (ics_left->ms_mask_present == 0)*/ {
258
21.8k
                        begin = min(base + ics_right->swb_offset[sfb], ics_right->swb_offset_max);
259
21.8k
                        end = min(base + ics_right->swb_offset[sfb+1], ics_right->swb_offset_max);
260
261
                        /* Generate random vector */
262
21.8k
                        gen_rand_vector(&spec_right[begin],
263
21.8k
                            ics_right->scale_factors[g][sfb], end - begin, sub, __r1, __r2);
264
21.8k
                    }
265
29.2k
                }
266
414k
            } /* sfb */
267
1.05M
            group++;
268
1.05M
        } /* b */
269
985k
    } /* g */
270
656k
}
pns_decode
Line
Count
Source
154
282k
{
155
282k
    uint8_t g, sfb, b;
156
282k
    uint16_t begin, end;
157
158
282k
    uint8_t group = 0;
159
282k
    uint16_t nshort = frame_len >> 3;
160
161
282k
    uint8_t sub = 0;
162
163
282k
#ifdef FIXED_POINT
164
    /* IMDCT scaling */
165
282k
    if (object_type == LD)
166
1.21k
    {
167
1.21k
        sub = 9 /*9*/;
168
280k
    } else {
169
280k
        if (ics_left->window_sequence == EIGHT_SHORT_SEQUENCE)
170
23.3k
            sub = 7 /*7*/;
171
257k
        else
172
257k
            sub = 10 /*10*/;
173
280k
    }
174
#else
175
    (void)object_type;
176
#endif
177
178
701k
    for (g = 0; g < ics_left->num_window_groups; g++)
179
419k
    {
180
        /* Do perceptual noise substitution decoding */
181
865k
        for (b = 0; b < ics_left->window_group_length[g]; b++)
182
445k
        {
183
445k
            uint16_t base = group * nshort;
184
649k
            for (sfb = 0; sfb < ics_left->max_sfb; sfb++)
185
204k
            {
186
204k
                uint32_t r1_dep = 0, r2_dep = 0;
187
188
204k
                if (is_noise(ics_left, g, sfb))
189
28.5k
                {
190
#ifdef LTP_DEC
191
                    /* Simultaneous use of LTP and PNS is not prevented in the
192
                       syntax. If both LTP, and PNS are enabled on the same
193
                       scalefactor band, PNS takes precedence, and no prediction
194
                       is applied to this band.
195
                    */
196
                    ics_left->ltp.long_used[sfb] = 0;
197
                    ics_left->ltp2.long_used[sfb] = 0;
198
#endif
199
200
#ifdef MAIN_DEC
201
                    /* For scalefactor bands coded using PNS the corresponding
202
                       predictors are switched to "off".
203
                    */
204
                    ics_left->pred.prediction_used[sfb] = 0;
205
#endif
206
28.5k
                    begin = min(base + ics_left->swb_offset[sfb], ics_left->swb_offset_max);
207
28.5k
                    end = min(base + ics_left->swb_offset[sfb+1], ics_left->swb_offset_max);
208
209
28.5k
                    r1_dep = *__r1;
210
28.5k
                    r2_dep = *__r2;
211
212
                    /* Generate random vector */
213
28.5k
                    gen_rand_vector(&spec_left[begin],
214
28.5k
                        ics_left->scale_factors[g][sfb], end - begin, sub, __r1, __r2);
215
28.5k
                }
216
217
/* From the spec:
218
   If the same scalefactor band and group is coded by perceptual noise
219
   substitution in both channels of a channel pair, the correlation of
220
   the noise signal can be controlled by means of the ms_used field: While
221
   the default noise generation process works independently for each channel
222
   (separate generation of random vectors), the same random vector is used
223
   for both channels if ms_used[] is set for a particular scalefactor band
224
   and group. In this case, no M/S stereo coding is carried out (because M/S
225
   stereo coding and noise substitution coding are mutually exclusive).
226
   If the same scalefactor band and group is coded by perceptual noise
227
   substitution in only one channel of a channel pair the setting of ms_used[]
228
   is not evaluated.
229
*/
230
204k
                if ((ics_right != NULL)
231
204k
                    && is_noise(ics_right, g, sfb))
232
17.8k
                {
233
#ifdef LTP_DEC
234
                    /* See comment above. */
235
                    ics_right->ltp.long_used[sfb] = 0;
236
                    ics_right->ltp2.long_used[sfb] = 0;
237
#endif
238
#ifdef MAIN_DEC
239
                    /* See comment above. */
240
                    ics_right->pred.prediction_used[sfb] = 0;
241
#endif
242
243
17.8k
                    if (channel_pair && is_noise(ics_left, g, sfb) &&
244
17.8k
                        (((ics_left->ms_mask_present == 1) &&
245
4.97k
                        (ics_left->ms_used[g][sfb])) ||
246
4.97k
                        (ics_left->ms_mask_present == 2)))
247
2.29k
                    {
248
                        /*uint16_t c;*/
249
250
2.29k
                        begin = min(base + ics_right->swb_offset[sfb], ics_right->swb_offset_max);
251
2.29k
                        end = min(base + ics_right->swb_offset[sfb+1], ics_right->swb_offset_max);
252
253
                        /* Generate random vector dependent on left channel*/
254
2.29k
                        gen_rand_vector(&spec_right[begin],
255
2.29k
                            ics_right->scale_factors[g][sfb], end - begin, sub, &r1_dep, &r2_dep);
256
257
15.5k
                    } else /*if (ics_left->ms_mask_present == 0)*/ {
258
15.5k
                        begin = min(base + ics_right->swb_offset[sfb], ics_right->swb_offset_max);
259
15.5k
                        end = min(base + ics_right->swb_offset[sfb+1], ics_right->swb_offset_max);
260
261
                        /* Generate random vector */
262
15.5k
                        gen_rand_vector(&spec_right[begin],
263
15.5k
                            ics_right->scale_factors[g][sfb], end - begin, sub, __r1, __r2);
264
15.5k
                    }
265
17.8k
                }
266
204k
            } /* sfb */
267
445k
            group++;
268
445k
        } /* b */
269
419k
    } /* g */
270
282k
}
pns_decode
Line
Count
Source
154
374k
{
155
374k
    uint8_t g, sfb, b;
156
374k
    uint16_t begin, end;
157
158
374k
    uint8_t group = 0;
159
374k
    uint16_t nshort = frame_len >> 3;
160
161
374k
    uint8_t sub = 0;
162
163
#ifdef FIXED_POINT
164
    /* IMDCT scaling */
165
    if (object_type == LD)
166
    {
167
        sub = 9 /*9*/;
168
    } else {
169
        if (ics_left->window_sequence == EIGHT_SHORT_SEQUENCE)
170
            sub = 7 /*7*/;
171
        else
172
            sub = 10 /*10*/;
173
    }
174
#else
175
374k
    (void)object_type;
176
374k
#endif
177
178
940k
    for (g = 0; g < ics_left->num_window_groups; g++)
179
565k
    {
180
        /* Do perceptual noise substitution decoding */
181
1.17M
        for (b = 0; b < ics_left->window_group_length[g]; b++)
182
613k
        {
183
613k
            uint16_t base = group * nshort;
184
823k
            for (sfb = 0; sfb < ics_left->max_sfb; sfb++)
185
210k
            {
186
210k
                uint32_t r1_dep = 0, r2_dep = 0;
187
188
210k
                if (is_noise(ics_left, g, sfb))
189
27.2k
                {
190
27.2k
#ifdef LTP_DEC
191
                    /* Simultaneous use of LTP and PNS is not prevented in the
192
                       syntax. If both LTP, and PNS are enabled on the same
193
                       scalefactor band, PNS takes precedence, and no prediction
194
                       is applied to this band.
195
                    */
196
27.2k
                    ics_left->ltp.long_used[sfb] = 0;
197
27.2k
                    ics_left->ltp2.long_used[sfb] = 0;
198
27.2k
#endif
199
200
27.2k
#ifdef MAIN_DEC
201
                    /* For scalefactor bands coded using PNS the corresponding
202
                       predictors are switched to "off".
203
                    */
204
27.2k
                    ics_left->pred.prediction_used[sfb] = 0;
205
27.2k
#endif
206
27.2k
                    begin = min(base + ics_left->swb_offset[sfb], ics_left->swb_offset_max);
207
27.2k
                    end = min(base + ics_left->swb_offset[sfb+1], ics_left->swb_offset_max);
208
209
27.2k
                    r1_dep = *__r1;
210
27.2k
                    r2_dep = *__r2;
211
212
                    /* Generate random vector */
213
27.2k
                    gen_rand_vector(&spec_left[begin],
214
27.2k
                        ics_left->scale_factors[g][sfb], end - begin, sub, __r1, __r2);
215
27.2k
                }
216
217
/* From the spec:
218
   If the same scalefactor band and group is coded by perceptual noise
219
   substitution in both channels of a channel pair, the correlation of
220
   the noise signal can be controlled by means of the ms_used field: While
221
   the default noise generation process works independently for each channel
222
   (separate generation of random vectors), the same random vector is used
223
   for both channels if ms_used[] is set for a particular scalefactor band
224
   and group. In this case, no M/S stereo coding is carried out (because M/S
225
   stereo coding and noise substitution coding are mutually exclusive).
226
   If the same scalefactor band and group is coded by perceptual noise
227
   substitution in only one channel of a channel pair the setting of ms_used[]
228
   is not evaluated.
229
*/
230
210k
                if ((ics_right != NULL)
231
210k
                    && is_noise(ics_right, g, sfb))
232
11.3k
                {
233
11.3k
#ifdef LTP_DEC
234
                    /* See comment above. */
235
11.3k
                    ics_right->ltp.long_used[sfb] = 0;
236
11.3k
                    ics_right->ltp2.long_used[sfb] = 0;
237
11.3k
#endif
238
11.3k
#ifdef MAIN_DEC
239
                    /* See comment above. */
240
11.3k
                    ics_right->pred.prediction_used[sfb] = 0;
241
11.3k
#endif
242
243
11.3k
                    if (channel_pair && is_noise(ics_left, g, sfb) &&
244
11.3k
                        (((ics_left->ms_mask_present == 1) &&
245
7.40k
                        (ics_left->ms_used[g][sfb])) ||
246
7.40k
                        (ics_left->ms_mask_present == 2)))
247
5.12k
                    {
248
                        /*uint16_t c;*/
249
250
5.12k
                        begin = min(base + ics_right->swb_offset[sfb], ics_right->swb_offset_max);
251
5.12k
                        end = min(base + ics_right->swb_offset[sfb+1], ics_right->swb_offset_max);
252
253
                        /* Generate random vector dependent on left channel*/
254
5.12k
                        gen_rand_vector(&spec_right[begin],
255
5.12k
                            ics_right->scale_factors[g][sfb], end - begin, sub, &r1_dep, &r2_dep);
256
257
6.26k
                    } else /*if (ics_left->ms_mask_present == 0)*/ {
258
6.26k
                        begin = min(base + ics_right->swb_offset[sfb], ics_right->swb_offset_max);
259
6.26k
                        end = min(base + ics_right->swb_offset[sfb+1], ics_right->swb_offset_max);
260
261
                        /* Generate random vector */
262
6.26k
                        gen_rand_vector(&spec_right[begin],
263
6.26k
                            ics_right->scale_factors[g][sfb], end - begin, sub, __r1, __r2);
264
6.26k
                    }
265
11.3k
                }
266
210k
            } /* sfb */
267
613k
            group++;
268
613k
        } /* b */
269
565k
    } /* g */
270
374k
}