GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/ac3enc.c Lines: 996 1194 83.4 %
Date: 2019-11-18 18:00:01 Branches: 625 870 71.8 %

Line Branch Exec Source
1
/*
2
 * The simplest AC-3 encoder
3
 * Copyright (c) 2000 Fabrice Bellard
4
 * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
5
 * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
6
 *
7
 * This file is part of FFmpeg.
8
 *
9
 * FFmpeg is free software; you can redistribute it and/or
10
 * modify it under the terms of the GNU Lesser General Public
11
 * License as published by the Free Software Foundation; either
12
 * version 2.1 of the License, or (at your option) any later version.
13
 *
14
 * FFmpeg is distributed in the hope that it will be useful,
15
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17
 * Lesser General Public License for more details.
18
 *
19
 * You should have received a copy of the GNU Lesser General Public
20
 * License along with FFmpeg; if not, write to the Free Software
21
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22
 */
23
24
/**
25
 * @file
26
 * The simplest AC-3 encoder.
27
 */
28
29
#include <stdint.h>
30
31
#include "libavutil/attributes.h"
32
#include "libavutil/avassert.h"
33
#include "libavutil/avstring.h"
34
#include "libavutil/channel_layout.h"
35
#include "libavutil/crc.h"
36
#include "libavutil/internal.h"
37
#include "libavutil/opt.h"
38
#include "avcodec.h"
39
#include "internal.h"
40
#include "me_cmp.h"
41
#include "put_bits.h"
42
#include "audiodsp.h"
43
#include "ac3dsp.h"
44
#include "ac3.h"
45
#include "fft.h"
46
#include "ac3enc.h"
47
#include "eac3enc.h"
48
49
typedef struct AC3Mant {
50
    int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
51
    int mant1_cnt, mant2_cnt, mant4_cnt;    ///< mantissa counts for bap=1,2,4
52
} AC3Mant;
53
54
#define CMIXLEV_NUM_OPTIONS 3
55
static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
56
    LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB
57
};
58
59
#define SURMIXLEV_NUM_OPTIONS 3
60
static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS] = {
61
    LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO
62
};
63
64
#define EXTMIXLEV_NUM_OPTIONS 8
65
static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS] = {
66
    LEVEL_PLUS_3DB,  LEVEL_PLUS_1POINT5DB,  LEVEL_ONE,       LEVEL_MINUS_4POINT5DB,
67
    LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB, LEVEL_ZERO
68
};
69
70
71
/**
72
 * LUT for number of exponent groups.
73
 * exponent_group_tab[coupling][exponent strategy-1][number of coefficients]
74
 */
75
static uint8_t exponent_group_tab[2][3][256];
76
77
78
/**
79
 * List of supported channel layouts.
80
 */
81
const uint64_t ff_ac3_channel_layouts[19] = {
82
     AV_CH_LAYOUT_MONO,
83
     AV_CH_LAYOUT_STEREO,
84
     AV_CH_LAYOUT_2_1,
85
     AV_CH_LAYOUT_SURROUND,
86
     AV_CH_LAYOUT_2_2,
87
     AV_CH_LAYOUT_QUAD,
88
     AV_CH_LAYOUT_4POINT0,
89
     AV_CH_LAYOUT_5POINT0,
90
     AV_CH_LAYOUT_5POINT0_BACK,
91
    (AV_CH_LAYOUT_MONO     | AV_CH_LOW_FREQUENCY),
92
    (AV_CH_LAYOUT_STEREO   | AV_CH_LOW_FREQUENCY),
93
    (AV_CH_LAYOUT_2_1      | AV_CH_LOW_FREQUENCY),
94
    (AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY),
95
    (AV_CH_LAYOUT_2_2      | AV_CH_LOW_FREQUENCY),
96
    (AV_CH_LAYOUT_QUAD     | AV_CH_LOW_FREQUENCY),
97
    (AV_CH_LAYOUT_4POINT0  | AV_CH_LOW_FREQUENCY),
98
     AV_CH_LAYOUT_5POINT1,
99
     AV_CH_LAYOUT_5POINT1_BACK,
100
     0
101
};
102
103
104
/**
105
 * LUT to select the bandwidth code based on the bit rate, sample rate, and
106
 * number of full-bandwidth channels.
107
 * bandwidth_tab[fbw_channels-1][sample rate code][bit rate code]
108
 */
109
static const uint8_t ac3_bandwidth_tab[5][3][19] = {
110
//      32  40  48  56  64  80  96 112 128 160 192 224 256 320 384 448 512 576 640
111
112
    { {  0,  0,  0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
113
      {  0,  0,  0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
114
      {  0,  0,  0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
115
116
    { {  0,  0,  0,  0,  0,  0,  0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
117
      {  0,  0,  0,  0,  0,  0,  4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
118
      {  0,  0,  0,  0,  0,  0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
119
120
    { {  0,  0,  0,  0,  0,  0,  0,  0,  0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
121
      {  0,  0,  0,  0,  0,  0,  0,  0,  4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
122
      {  0,  0,  0,  0,  0,  0,  0,  0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
123
124
    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
125
      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
126
      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
127
128
    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  8, 20, 32, 40, 48, 48, 48, 48 },
129
      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 12, 24, 36, 44, 56, 56, 56, 56 },
130
      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 28, 44, 60, 60, 60, 60, 60, 60 } }
131
};
132
133
134
/**
135
 * LUT to select the coupling start band based on the bit rate, sample rate, and
136
 * number of full-bandwidth channels. -1 = coupling off
137
 * ac3_coupling_start_tab[channel_mode-2][sample rate code][bit rate code]
138
 *
139
 * TODO: more testing for optimal parameters.
140
 *       multi-channel tests at 44.1kHz and 32kHz.
141
 */
142
static const int8_t ac3_coupling_start_tab[6][3][19] = {
143
//      32  40  48  56  64  80  96 112 128 160 192 224 256 320 384 448 512 576 640
144
145
    // 2/0
146
    { {  0,  0,  0,  0,  0,  0,  0,  1,  1,  7,  8, 11, 12, -1, -1, -1, -1, -1, -1 },
147
      {  0,  0,  0,  0,  0,  0,  1,  3,  5,  7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
148
      {  0,  0,  0,  0,  1,  2,  2,  9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
149
150
    // 3/0
151
    { {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
152
      {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
153
      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
154
155
    // 2/1 - untested
156
    { {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
157
      {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
158
      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
159
160
    // 3/1
161
    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
162
      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
163
      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
164
165
    // 2/2 - untested
166
    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
167
      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
168
      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
169
170
    // 3/2
171
    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  6,  8, 11, 12, 12, -1, -1 },
172
      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  6,  8, 11, 12, 12, -1, -1 },
173
      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
174
};
175
176
177
/**
178
 * Adjust the frame size to make the average bit rate match the target bit rate.
179
 * This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3.
180
 *
181
 * @param s  AC-3 encoder private context
182
 */
183
1097
void ff_ac3_adjust_frame_size(AC3EncodeContext *s)
184
{
185

1131
    while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
186
34
        s->bits_written    -= s->bit_rate;
187
34
        s->samples_written -= s->sample_rate;
188
    }
189
2194
    s->frame_size = s->frame_size_min +
190
1097
                    2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
191
1097
    s->bits_written    += s->frame_size * 8;
192
1097
    s->samples_written += AC3_BLOCK_SIZE * s->num_blocks;
193
1097
}
194
195
196
/**
197
 * Set the initial coupling strategy parameters prior to coupling analysis.
198
 *
199
 * @param s  AC-3 encoder private context
200
 */
201
1097
void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
202
{
203
    int blk, ch;
204
    int got_cpl_snr;
205
    int num_cpl_blocks;
206
207
    /* set coupling use flags for each block/channel */
208
    /* TODO: turn coupling on/off and adjust start band based on bit usage */
209
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
210
6582
        AC3Block *block = &s->blocks[blk];
211
17478
        for (ch = 1; ch <= s->fbw_channels; ch++)
212
10896
            block->channel_in_cpl[ch] = s->cpl_on;
213
    }
214
215
    /* enable coupling for each block if at least 2 channels have coupling
216
       enabled for that block */
217
1097
    got_cpl_snr = 0;
218
1097
    num_cpl_blocks = 0;
219
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
220
6582
        AC3Block *block = &s->blocks[blk];
221
6582
        block->num_cpl_channels = 0;
222
17478
        for (ch = 1; ch <= s->fbw_channels; ch++)
223
10896
            block->num_cpl_channels += block->channel_in_cpl[ch];
224
6582
        block->cpl_in_use = block->num_cpl_channels > 1;
225
6582
        num_cpl_blocks += block->cpl_in_use;
226
6582
        if (!block->cpl_in_use) {
227
2268
            block->num_cpl_channels = 0;
228
4536
            for (ch = 1; ch <= s->fbw_channels; ch++)
229
2268
                block->channel_in_cpl[ch] = 0;
230
        }
231
232
6582
        block->new_cpl_strategy = !blk;
233
6582
        if (blk) {
234
14565
            for (ch = 1; ch <= s->fbw_channels; ch++) {
235
9080
                if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
236
                    block->new_cpl_strategy = 1;
237
                    break;
238
                }
239
            }
240
        }
241
6582
        block->new_cpl_leak = block->new_cpl_strategy;
242
243

6582
        if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
244
1097
            block->new_snr_offsets = 1;
245
1097
            if (block->cpl_in_use)
246
719
                got_cpl_snr = 1;
247
        } else {
248
5485
            block->new_snr_offsets = 0;
249
        }
250
    }
251
1097
    if (!num_cpl_blocks)
252
378
        s->cpl_on = 0;
253
254
    /* set bandwidth for each channel */
255
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
256
6582
        AC3Block *block = &s->blocks[blk];
257
17478
        for (ch = 1; ch <= s->fbw_channels; ch++) {
258
10896
            if (block->channel_in_cpl[ch])
259
8628
                block->end_freq[ch] = s->start_freq[CPL_CH];
260
            else
261
2268
                block->end_freq[ch] = s->bandwidth_code * 3 + 73;
262
        }
263
    }
264
1097
}
265
266
267
/**
268
 * Apply stereo rematrixing to coefficients based on rematrixing flags.
269
 *
270
 * @param s  AC-3 encoder private context
271
 */
272
1097
void ff_ac3_apply_rematrixing(AC3EncodeContext *s)
273
{
274
    int nb_coefs;
275
    int blk, bnd, i;
276
    int start, end;
277
1097
    uint8_t *flags = NULL;
278
279
1097
    if (!s->rematrixing_enabled)
280
378
        return;
281
282
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
283
4314
        AC3Block *block = &s->blocks[blk];
284
4314
        if (block->new_rematrixing_strategy)
285
2214
            flags = block->rematrixing_flags;
286
4314
        nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
287
21570
        for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
288
17256
            if (flags[bnd]) {
289
9589
                start = ff_ac3_rematrix_band_tab[bnd];
290
9589
                end   = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
291
226249
                for (i = start; i < end; i++) {
292
216660
                    int32_t lt = block->fixed_coef[1][i];
293
216660
                    int32_t rt = block->fixed_coef[2][i];
294
216660
                    block->fixed_coef[1][i] = (lt + rt) >> 1;
295
216660
                    block->fixed_coef[2][i] = (lt - rt) >> 1;
296
                }
297
            }
298
        }
299
    }
300
}
301
302
303
/*
304
 * Initialize exponent tables.
305
 */
306
6
static av_cold void exponent_init(AC3EncodeContext *s)
307
{
308
    int expstr, i, grpsize;
309
310
24
    for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
311
18
        grpsize = 3 << expstr;
312
4410
        for (i = 12; i < 256; i++) {
313
4392
            exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
314
4392
            exponent_group_tab[1][expstr][i] = (i              ) / grpsize;
315
        }
316
    }
317
    /* LFE */
318
6
    exponent_group_tab[0][0][7] = 2;
319
320
6
    if (CONFIG_EAC3_ENCODER && s->eac3)
321
1
        ff_eac3_exponent_init();
322
6
}
323
324
325
/*
326
 * Extract exponents from the MDCT coefficients.
327
 */
328
1097
static void extract_exponents(AC3EncodeContext *s)
329
{
330
1097
    int ch        = !s->cpl_on;
331
1097
    int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
332
1097
    AC3Block *block = &s->blocks[0];
333
334
1097
    s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
335
1097
}
336
337
338
/**
339
 * Exponent Difference Threshold.
340
 * New exponents are sent if their SAD exceed this number.
341
 */
342
#define EXP_DIFF_THRESHOLD 500
343
344
/**
345
 * Table used to select exponent strategy based on exponent reuse block interval.
346
 */
347
static const uint8_t exp_strategy_reuse_tab[4][6] = {
348
    { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
349
    { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
350
    { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
351
    { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 }
352
};
353
354
/*
355
 * Calculate exponent strategies for all channels.
356
 * Array arrangement is reversed to simplify the per-channel calculation.
357
 */
358
1097
static void compute_exp_strategy(AC3EncodeContext *s)
359
{
360
    int ch, blk, blk1;
361
362
3632
    for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
363
2535
        uint8_t *exp_strategy = s->exp_strategy[ch];
364
2535
        uint8_t *exp          = s->blocks[0].exp[ch];
365
        int exp_diff;
366
367
        /* estimate if the exponent variation & decide if they should be
368
           reused in the next frame */
369
2535
        exp_strategy[0] = EXP_NEW;
370
2535
        exp += AC3_MAX_COEFS;
371
15210
        for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
372
12675
            if (ch == CPL_CH) {
373
3595
                if (!s->blocks[blk-1].cpl_in_use) {
374
                    exp_strategy[blk] = EXP_NEW;
375
                    continue;
376
3595
                } else if (!s->blocks[blk].cpl_in_use) {
377
                    exp_strategy[blk] = EXP_REUSE;
378
                    continue;
379
                }
380
9080
            } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
381
                exp_strategy[blk] = EXP_NEW;
382
                continue;
383
            }
384
12675
            exp_diff = s->mecc.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
385
12675
            exp_strategy[blk] = EXP_REUSE;
386

12675
            if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
387
1363
                exp_strategy[blk] = EXP_NEW;
388

11312
            else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
389
2488
                exp_strategy[blk] = EXP_NEW;
390
        }
391
392
        /* now select the encoding strategy type : if exponents are often
393
           recoded, we use a coarse encoding */
394
2535
        blk = 0;
395
8921
        while (blk < s->num_blocks) {
396
6386
            blk1 = blk + 1;
397

15210
            while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
398
8824
                blk1++;
399
6386
            exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
400
6386
            blk = blk1;
401
        }
402
    }
403
1097
    if (s->lfe_on) {
404
        ch = s->lfe_channel;
405
        s->exp_strategy[ch][0] = EXP_D15;
406
        for (blk = 1; blk < s->num_blocks; blk++)
407
            s->exp_strategy[ch][blk] = EXP_REUSE;
408
    }
409
410
    /* for E-AC-3, determine frame exponent strategy */
411
1097
    if (CONFIG_EAC3_ENCODER && s->eac3)
412
273
        ff_eac3_get_frame_exp_strategy(s);
413
1097
}
414
415
416
/**
417
 * Update the exponents so that they are the ones the decoder will decode.
418
 *
419
 * @param[in,out] exp   array of exponents for 1 block in 1 channel
420
 * @param nb_exps       number of exponents in active bandwidth
421
 * @param exp_strategy  exponent strategy for the block
422
 * @param cpl           indicates if the block is in the coupling channel
423
 */
424
6386
static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
425
                                    int cpl)
426
{
427
    int nb_groups, i, k;
428
429
6386
    nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
430
431
    /* for each group, compute the minimum exponent */
432
6386
    switch(exp_strategy) {
433
731
    case EXP_D25:
434
36791
        for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
435
36060
            uint8_t exp_min = exp[k];
436
36060
            if (exp[k+1] < exp_min)
437
12598
                exp_min = exp[k+1];
438
36060
            exp[i-cpl] = exp_min;
439
36060
            k += 2;
440
        }
441
731
        break;
442
3991
    case EXP_D45:
443
143218
        for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
444
139227
            uint8_t exp_min = exp[k];
445
139227
            if (exp[k+1] < exp_min)
446
49876
                exp_min = exp[k+1];
447
139227
            if (exp[k+2] < exp_min)
448
23643
                exp_min = exp[k+2];
449
139227
            if (exp[k+3] < exp_min)
450
16576
                exp_min = exp[k+3];
451
139227
            exp[i-cpl] = exp_min;
452
139227
            k += 4;
453
        }
454
3991
        break;
455
    }
456
457
    /* constraint for DC exponent */
458

6386
    if (!cpl && exp[0] > 15)
459
78
        exp[0] = 15;
460
461
    /* decrease the delta between each groups to within 2 so that they can be
462
       differentially encoded */
463
336089
    for (i = 1; i <= nb_groups; i++)
464
329703
        exp[i] = FFMIN(exp[i], exp[i-1] + 2);
465
6386
    i--;
466
336089
    while (--i >= 0)
467
329703
        exp[i] = FFMIN(exp[i], exp[i+1] + 2);
468
469
6386
    if (cpl)
470
2082
        exp[-1] = exp[0] & ~1;
471
472
    /* now we have the exponent values the decoder will see */
473
6386
    switch (exp_strategy) {
474
731
    case EXP_D25:
475
36791
        for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
476
36060
            uint8_t exp1 = exp[i-cpl];
477
36060
            exp[k--] = exp1;
478
36060
            exp[k--] = exp1;
479
        }
480
731
        break;
481
3991
    case EXP_D45:
482
143218
        for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
483
139227
            exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
484
139227
            k -= 4;
485
        }
486
3991
        break;
487
    }
488
6386
}
489
490
491
/*
492
 * Encode exponents from original extracted form to what the decoder will see.
493
 * This copies and groups exponents based on exponent strategy and reduces
494
 * deltas between adjacent exponent groups so that they can be differentially
495
 * encoded.
496
 */
497
1097
static void encode_exponents(AC3EncodeContext *s)
498
{
499
    int blk, blk1, ch, cpl;
500
    uint8_t *exp, *exp_strategy;
501
    int nb_coefs, num_reuse_blocks;
502
503
3632
    for (ch = !s->cpl_on; ch <= s->channels; ch++) {
504
2535
        exp          = s->blocks[0].exp[ch] + s->start_freq[ch];
505
2535
        exp_strategy = s->exp_strategy[ch];
506
507
2535
        cpl = (ch == CPL_CH);
508
2535
        blk = 0;
509
8921
        while (blk < s->num_blocks) {
510
6386
            AC3Block *block = &s->blocks[blk];
511

6386
            if (cpl && !block->cpl_in_use) {
512
                exp += AC3_MAX_COEFS;
513
                blk++;
514
                continue;
515
            }
516
6386
            nb_coefs = block->end_freq[ch] - s->start_freq[ch];
517
6386
            blk1 = blk + 1;
518
519
            /* count the number of EXP_REUSE blocks after the current block
520
               and set exponent reference block numbers */
521
6386
            s->exp_ref_block[ch][blk] = blk;
522

15210
            while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
523
8824
                s->exp_ref_block[ch][blk1] = blk;
524
8824
                blk1++;
525
            }
526
6386
            num_reuse_blocks = blk1 - blk - 1;
527
528
            /* for the EXP_REUSE case we select the min of the exponents */
529
6386
            s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
530
                                       AC3_MAX_COEFS);
531
532
6386
            encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
533
534
6386
            exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
535
6386
            blk = blk1;
536
        }
537
    }
538
539
    /* reference block numbers have been changed, so reset ref_bap_set */
540
1097
    s->ref_bap_set = 0;
541
1097
}
542
543
544
/*
545
 * Count exponent bits based on bandwidth, coupling, and exponent strategies.
546
 */
547
1097
static int count_exponent_bits(AC3EncodeContext *s)
548
{
549
    int blk, ch;
550
    int nb_groups, bit_count;
551
552
1097
    bit_count = 0;
553
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
554
6582
        AC3Block *block = &s->blocks[blk];
555
21792
        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
556
15210
            int exp_strategy = s->exp_strategy[ch][blk];
557
15210
            int cpl          = (ch == CPL_CH);
558
15210
            int nb_coefs     = block->end_freq[ch] - s->start_freq[ch];
559
560
15210
            if (exp_strategy == EXP_REUSE)
561
8824
                continue;
562
563
6386
            nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
564
6386
            bit_count += 4 + (nb_groups * 7);
565
        }
566
    }
567
568
1097
    return bit_count;
569
}
570
571
572
/**
573
 * Group exponents.
574
 * 3 delta-encoded exponents are in each 7-bit group. The number of groups
575
 * varies depending on exponent strategy and bandwidth.
576
 *
577
 * @param s  AC-3 encoder private context
578
 */
579
1097
void ff_ac3_group_exponents(AC3EncodeContext *s)
580
{
581
    int blk, ch, i, cpl;
582
    int group_size, nb_groups;
583
    uint8_t *p;
584
    int delta0, delta1, delta2;
585
    int exp0, exp1;
586
587
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
588
6582
        AC3Block *block = &s->blocks[blk];
589
21792
        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
590
15210
            int exp_strategy = s->exp_strategy[ch][blk];
591
15210
            if (exp_strategy == EXP_REUSE)
592
8824
                continue;
593
6386
            cpl = (ch == CPL_CH);
594
6386
            group_size = exp_strategy + (exp_strategy == EXP_D45);
595
6386
            nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
596
6386
            p = block->exp[ch] + s->start_freq[ch] - cpl;
597
598
            /* DC exponent */
599
6386
            exp1 = *p++;
600
6386
            block->grouped_exp[ch][0] = exp1;
601
602
            /* remaining exponents are delta encoded */
603
116287
            for (i = 1; i <= nb_groups; i++) {
604
                /* merge three delta in one code */
605
109901
                exp0   = exp1;
606
109901
                exp1   = p[0];
607
109901
                p     += group_size;
608
109901
                delta0 = exp1 - exp0 + 2;
609
                av_assert2(delta0 >= 0 && delta0 <= 4);
610
611
109901
                exp0   = exp1;
612
109901
                exp1   = p[0];
613
109901
                p     += group_size;
614
109901
                delta1 = exp1 - exp0 + 2;
615
                av_assert2(delta1 >= 0 && delta1 <= 4);
616
617
109901
                exp0   = exp1;
618
109901
                exp1   = p[0];
619
109901
                p     += group_size;
620
109901
                delta2 = exp1 - exp0 + 2;
621
                av_assert2(delta2 >= 0 && delta2 <= 4);
622
623
109901
                block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
624
            }
625
        }
626
    }
627
1097
}
628
629
630
/**
631
 * Calculate final exponents from the supplied MDCT coefficients and exponent shift.
632
 * Extract exponents from MDCT coefficients, calculate exponent strategies,
633
 * and encode final exponents.
634
 *
635
 * @param s  AC-3 encoder private context
636
 */
637
1097
void ff_ac3_process_exponents(AC3EncodeContext *s)
638
{
639
1097
    extract_exponents(s);
640
641
1097
    compute_exp_strategy(s);
642
643
1097
    encode_exponents(s);
644
645
1097
    emms_c();
646
1097
}
647
648
649
/*
650
 * Count frame bits that are based solely on fixed parameters.
651
 * This only has to be run once when the encoder is initialized.
652
 */
653
6
static void count_frame_bits_fixed(AC3EncodeContext *s)
654
{
655
    static const uint8_t frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
656
    int blk;
657
    int frame_bits;
658
659
    /* assumptions:
660
     *   no dynamic range codes
661
     *   bit allocation parameters do not change between blocks
662
     *   no delta bit allocation
663
     *   no skipped data
664
     *   no auxiliary data
665
     *   no E-AC-3 metadata
666
     */
667
668
    /* header */
669
6
    frame_bits = 16; /* sync info */
670
6
    if (s->eac3) {
671
        /* bitstream info header */
672
1
        frame_bits += 35;
673
1
        frame_bits += 1 + 1;
674
1
        if (s->num_blocks != 0x6)
675
            frame_bits++;
676
1
        frame_bits++;
677
        /* audio frame header */
678
1
        if (s->num_blocks == 6)
679
1
            frame_bits += 2;
680
1
        frame_bits += 10;
681
        /* exponent strategy */
682
1
        if (s->use_frame_exp_strategy)
683
            frame_bits += 5 * s->fbw_channels;
684
        else
685
1
            frame_bits += s->num_blocks * 2 * s->fbw_channels;
686
1
        if (s->lfe_on)
687
            frame_bits += s->num_blocks;
688
        /* converter exponent strategy */
689
1
        if (s->num_blks_code != 0x3)
690
            frame_bits++;
691
        else
692
1
            frame_bits += s->fbw_channels * 5;
693
        /* snr offsets */
694
1
        frame_bits += 10;
695
        /* block start info */
696
1
        if (s->num_blocks != 1)
697
1
            frame_bits++;
698
    } else {
699
5
        frame_bits += 49;
700
5
        frame_bits += frame_bits_inc[s->channel_mode];
701
    }
702
703
    /* audio blocks */
704
42
    for (blk = 0; blk < s->num_blocks; blk++) {
705
36
        if (!s->eac3) {
706
            /* block switch flags */
707
30
            frame_bits += s->fbw_channels;
708
709
            /* dither flags */
710
30
            frame_bits += s->fbw_channels;
711
        }
712
713
        /* dynamic range */
714
36
        frame_bits++;
715
716
        /* spectral extension */
717
36
        if (s->eac3)
718
6
            frame_bits++;
719
720
36
        if (!s->eac3) {
721
            /* exponent strategy */
722
30
            frame_bits += 2 * s->fbw_channels;
723
30
            if (s->lfe_on)
724
                frame_bits++;
725
726
            /* bit allocation params */
727
30
            frame_bits++;
728
30
            if (!blk)
729
5
                frame_bits += 2 + 2 + 2 + 2 + 3;
730
        }
731
732
        /* converter snr offset */
733
36
        if (s->eac3)
734
6
            frame_bits++;
735
736
36
        if (!s->eac3) {
737
            /* delta bit allocation */
738
30
            frame_bits++;
739
740
            /* skipped data */
741
30
            frame_bits++;
742
        }
743
    }
744
745
    /* auxiliary data */
746
6
    frame_bits++;
747
748
    /* CRC */
749
6
    frame_bits += 1 + 16;
750
751
6
    s->frame_bits_fixed = frame_bits;
752
6
}
753
754
755
/*
756
 * Initialize bit allocation.
757
 * Set default parameter codes and calculate parameter values.
758
 */
759
6
static av_cold void bit_alloc_init(AC3EncodeContext *s)
760
{
761
    int ch;
762
763
    /* init default parameters */
764
6
    s->slow_decay_code = 2;
765
6
    s->fast_decay_code = 1;
766
6
    s->slow_gain_code  = 1;
767
6
    s->db_per_bit_code = s->eac3 ? 2 : 3;
768
6
    s->floor_code      = 7;
769
21
    for (ch = 0; ch <= s->channels; ch++)
770
15
        s->fast_gain_code[ch] = 4;
771
772
    /* initial snr offset */
773
6
    s->coarse_snr_offset = 40;
774
775
    /* compute real values */
776
    /* currently none of these values change during encoding, so we can just
777
       set them once at initialization */
778
6
    s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift;
779
6
    s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift;
780
6
    s->bit_alloc.slow_gain  = ff_ac3_slow_gain_tab[s->slow_gain_code];
781
6
    s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
782
6
    s->bit_alloc.floor      = ff_ac3_floor_tab[s->floor_code];
783
6
    s->bit_alloc.cpl_fast_leak = 0;
784
6
    s->bit_alloc.cpl_slow_leak = 0;
785
786
6
    count_frame_bits_fixed(s);
787
6
}
788
789
790
/*
791
 * Count the bits used to encode the frame, minus exponents and mantissas.
792
 * Bits based on fixed parameters have already been counted, so now we just
793
 * have to add the bits based on parameters that change during encoding.
794
 */
795
1097
static void count_frame_bits(AC3EncodeContext *s)
796
{
797
1097
    AC3EncOptions *opt = &s->options;
798
    int blk, ch;
799
1097
    int frame_bits = 0;
800
801
    /* header */
802
1097
    if (s->eac3) {
803
273
        if (opt->eac3_mixing_metadata) {
804
            if (s->channel_mode > AC3_CHMODE_STEREO)
805
                frame_bits += 2;
806
            if (s->has_center)
807
                frame_bits += 6;
808
            if (s->has_surround)
809
                frame_bits += 6;
810
            frame_bits += s->lfe_on;
811
            frame_bits += 1 + 1 + 2;
812
            if (s->channel_mode < AC3_CHMODE_STEREO)
813
                frame_bits++;
814
            frame_bits++;
815
        }
816
273
        if (opt->eac3_info_metadata) {
817
            frame_bits += 3 + 1 + 1;
818
            if (s->channel_mode == AC3_CHMODE_STEREO)
819
                frame_bits += 2 + 2;
820
            if (s->channel_mode >= AC3_CHMODE_2F2R)
821
                frame_bits += 2;
822
            frame_bits++;
823
            if (opt->audio_production_info)
824
                frame_bits += 5 + 2 + 1;
825
            frame_bits++;
826
        }
827
        /* coupling */
828
273
        if (s->channel_mode > AC3_CHMODE_MONO) {
829
273
            frame_bits++;
830
1638
            for (blk = 1; blk < s->num_blocks; blk++) {
831
1365
                AC3Block *block = &s->blocks[blk];
832
1365
                frame_bits++;
833
1365
                if (block->new_cpl_strategy)
834
                    frame_bits++;
835
            }
836
        }
837
        /* coupling exponent strategy */
838
273
        if (s->cpl_on) {
839
273
            if (s->use_frame_exp_strategy) {
840
273
                frame_bits += 5 * s->cpl_on;
841
            } else {
842
                for (blk = 0; blk < s->num_blocks; blk++)
843
                    frame_bits += 2 * s->blocks[blk].cpl_in_use;
844
            }
845
        }
846
    } else {
847
824
        if (opt->audio_production_info)
848
            frame_bits += 7;
849
824
        if (s->bitstream_id == 6) {
850
            if (opt->extended_bsi_1)
851
                frame_bits += 14;
852
            if (opt->extended_bsi_2)
853
                frame_bits += 14;
854
        }
855
    }
856
857
    /* audio blocks */
858
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
859
6582
        AC3Block *block = &s->blocks[blk];
860
861
        /* coupling strategy */
862
6582
        if (!s->eac3)
863
4944
            frame_bits++;
864
6582
        if (block->new_cpl_strategy) {
865
1097
            if (!s->eac3)
866
824
                frame_bits++;
867
1097
            if (block->cpl_in_use) {
868
719
                if (s->eac3)
869
273
                    frame_bits++;
870

719
                if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
871
446
                    frame_bits += s->fbw_channels;
872
719
                if (s->channel_mode == AC3_CHMODE_STEREO)
873
719
                    frame_bits++;
874
719
                frame_bits += 4 + 4;
875
719
                if (s->eac3)
876
273
                    frame_bits++;
877
                else
878
446
                    frame_bits += s->num_cpl_subbands - 1;
879
            }
880
        }
881
882
        /* coupling coordinates */
883
6582
        if (block->cpl_in_use) {
884
12942
            for (ch = 1; ch <= s->fbw_channels; ch++) {
885
8628
                if (block->channel_in_cpl[ch]) {
886

8628
                    if (!s->eac3 || block->new_cpl_coords[ch] != 2)
887
8082
                        frame_bits++;
888
8628
                    if (block->new_cpl_coords[ch]) {
889
1470
                        frame_bits += 2;
890
1470
                        frame_bits += (4 + 4) * s->num_cpl_bands;
891
                    }
892
                }
893
            }
894
        }
895
896
        /* stereo rematrixing */
897
6582
        if (s->channel_mode == AC3_CHMODE_STEREO) {
898

4314
            if (!s->eac3 || blk > 0)
899
4041
                frame_bits++;
900
4314
            if (s->blocks[blk].new_rematrixing_strategy)
901
2214
                frame_bits += block->num_rematrixing_bands;
902
        }
903
904
        /* bandwidth codes & gain range */
905
17478
        for (ch = 1; ch <= s->fbw_channels; ch++) {
906
10896
            if (s->exp_strategy[ch][blk] != EXP_REUSE) {
907
4304
                if (!block->channel_in_cpl[ch])
908
1826
                    frame_bits += 6;
909
4304
                frame_bits += 2;
910
            }
911
        }
912
913
        /* coupling exponent strategy */
914

6582
        if (!s->eac3 && block->cpl_in_use)
915
2676
            frame_bits += 2;
916
917
        /* snr offsets and fast gain codes */
918
6582
        if (!s->eac3) {
919
4944
            frame_bits++;
920
4944
            if (block->new_snr_offsets)
921
824
                frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
922
        }
923
924
        /* coupling leak info */
925
6582
        if (block->cpl_in_use) {
926

4314
            if (!s->eac3 || block->new_cpl_leak != 2)
927
4041
                frame_bits++;
928
4314
            if (block->new_cpl_leak)
929
719
                frame_bits += 3 + 3;
930
        }
931
    }
932
933
1097
    s->frame_bits = s->frame_bits_fixed + frame_bits;
934
1097
}
935
936
937
/*
938
 * Calculate masking curve based on the final exponents.
939
 * Also calculate the power spectral densities to use in future calculations.
940
 */
941
1097
static void bit_alloc_masking(AC3EncodeContext *s)
942
{
943
    int blk, ch;
944
945
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
946
6582
        AC3Block *block = &s->blocks[blk];
947
21792
        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
948
            /* We only need psd and mask for calculating bap.
949
               Since we currently do not calculate bap when exponent
950
               strategy is EXP_REUSE we do not need to calculate psd or mask. */
951
15210
            if (s->exp_strategy[ch][blk] != EXP_REUSE) {
952
6386
                ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
953
6386
                                          block->end_freq[ch], block->psd[ch],
954
6386
                                          block->band_psd[ch]);
955
6386
                ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch],
956
                                           s->start_freq[ch], block->end_freq[ch],
957
6386
                                           ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],
958
6386
                                           ch == s->lfe_channel,
959
                                           DBA_NONE, 0, NULL, NULL, NULL,
960
6386
                                           block->mask[ch]);
961
            }
962
        }
963
    }
964
1097
}
965
966
967
/*
968
 * Ensure that bap for each block and channel point to the current bap_buffer.
969
 * They may have been switched during the bit allocation search.
970
 */
971
10437
static void reset_block_bap(AC3EncodeContext *s)
972
{
973
    int blk, ch;
974
    uint8_t *ref_bap;
975
976

10437
    if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
977
3538
        return;
978
979
6899
    ref_bap = s->bap_buffer;
980
25096
    for (ch = 0; ch <= s->channels; ch++) {
981
127379
        for (blk = 0; blk < s->num_blocks; blk++)
982
109182
            s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
983
18197
        ref_bap += AC3_MAX_COEFS * s->num_blocks;
984
    }
985
6899
    s->ref_bap_set = 1;
986
}
987
988
989
/**
990
 * Initialize mantissa counts.
991
 * These are set so that they are padded to the next whole group size when bits
992
 * are counted in compute_mantissa_size.
993
 *
994
 * @param[in,out] mant_cnt  running counts for each bap value for each block
995
 */
996
9340
static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
997
{
998
    int blk;
999
1000
65380
    for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
1001
56040
        memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
1002
56040
        mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
1003
56040
        mant_cnt[blk][4] = 1;
1004
    }
1005
9340
}
1006
1007
1008
/**
1009
 * Update mantissa bit counts for all blocks in 1 channel in a given bandwidth
1010
 * range.
1011
 *
1012
 * @param s                 AC-3 encoder private context
1013
 * @param ch                channel index
1014
 * @param[in,out] mant_cnt  running counts for each bap value for each block
1015
 * @param start             starting coefficient bin
1016
 * @param end               ending coefficient bin
1017
 */
1018
21280
static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch,
1019
                                          uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
1020
                                          int start, int end)
1021
{
1022
    int blk;
1023
1024
148960
    for (blk = 0; blk < s->num_blocks; blk++) {
1025
127680
        AC3Block *block = &s->blocks[blk];
1026

127680
        if (ch == CPL_CH && !block->cpl_in_use)
1027
            continue;
1028
127680
        s->ac3dsp.update_bap_counts(mant_cnt[blk],
1029
127680
                                    s->ref_bap[ch][blk] + start,
1030
127680
                                    FFMIN(end, block->end_freq[ch]) - start);
1031
    }
1032
21280
}
1033
1034
1035
/*
1036
 * Count the number of mantissa bits in the frame based on the bap values.
1037
 */
1038
9340
static int count_mantissa_bits(AC3EncodeContext *s)
1039
{
1040
    int ch, max_end_freq;
1041
9340
    LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
1042
1043
9340
    count_mantissa_bits_init(mant_cnt);
1044
1045
9340
    max_end_freq = s->bandwidth_code * 3 + 73;
1046
30620
    for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
1047
21280
        count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
1048
                                      max_end_freq);
1049
1050
9340
    return s->ac3dsp.compute_mantissa_size(mant_cnt);
1051
}
1052
1053
1054
/**
1055
 * Run the bit allocation with a given SNR offset.
1056
 * This calculates the bit allocation pointers that will be used to determine
1057
 * the quantization of each mantissa.
1058
 *
1059
 * @param s           AC-3 encoder private context
1060
 * @param snr_offset  SNR offset, 0 to 1023
1061
 * @return the number of bits needed for mantissas if the given SNR offset is
1062
 *         is used.
1063
 */
1064
9340
static int bit_alloc(AC3EncodeContext *s, int snr_offset)
1065
{
1066
    int blk, ch;
1067
1068
9340
    snr_offset = (snr_offset - 240) * 4;
1069
1070
9340
    reset_block_bap(s);
1071
65380
    for (blk = 0; blk < s->num_blocks; blk++) {
1072
56040
        AC3Block *block = &s->blocks[blk];
1073
1074
183720
        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1075
            /* Currently the only bit allocation parameters which vary across
1076
               blocks within a frame are the exponent values.  We can take
1077
               advantage of that by reusing the bit allocation pointers
1078
               whenever we reuse exponents. */
1079
127680
            if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1080
54306
                s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
1081
                                             s->start_freq[ch], block->end_freq[ch],
1082
                                             snr_offset, s->bit_alloc.floor,
1083
                                             ff_ac3_bap_tab, s->ref_bap[ch][blk]);
1084
            }
1085
        }
1086
    }
1087
9340
    return count_mantissa_bits(s);
1088
}
1089
1090
1091
/*
1092
 * Constant bitrate bit allocation search.
1093
 * Find the largest SNR offset that will allow data to fit in the frame.
1094
 */
1095
1097
static int cbr_bit_allocation(AC3EncodeContext *s)
1096
{
1097
    int ch;
1098
    int bits_left;
1099
    int snr_offset, snr_incr;
1100
1101
1097
    bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
1102
1097
    if (bits_left < 0)
1103
        return AVERROR(EINVAL);
1104
1105
1097
    snr_offset = s->coarse_snr_offset << 4;
1106
1107
    /* if previous frame SNR offset was 1023, check if current frame can also
1108
       use SNR offset of 1023. if so, skip the search. */
1109
1097
    if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
1110
        if (bit_alloc(s, 1023) <= bits_left)
1111
            return 0;
1112
    }
1113
1114

2688
    while (snr_offset >= 0 &&
1115
1344
           bit_alloc(s, snr_offset) > bits_left) {
1116
247
        snr_offset -= 64;
1117
    }
1118
1097
    if (snr_offset < 0)
1119
        return AVERROR(EINVAL);
1120
1121
1097
    FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1122
5485
    for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
1123

15992
        while (snr_offset + snr_incr <= 1023 &&
1124
7996
               bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
1125
3608
            snr_offset += snr_incr;
1126
3608
            FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1127
        }
1128
    }
1129
1097
    FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1130
1097
    reset_block_bap(s);
1131
1132
1097
    s->coarse_snr_offset = snr_offset >> 4;
1133
3632
    for (ch = !s->cpl_on; ch <= s->channels; ch++)
1134
2535
        s->fine_snr_offset[ch] = snr_offset & 0xF;
1135
1136
1097
    return 0;
1137
}
1138
1139
1140
/*
1141
 * Perform bit allocation search.
1142
 * Finds the SNR offset value that maximizes quality and fits in the specified
1143
 * frame size.  Output is the SNR offset and a set of bit allocation pointers
1144
 * used to quantize the mantissas.
1145
 */
1146
1097
int ff_ac3_compute_bit_allocation(AC3EncodeContext *s)
1147
{
1148
1097
    count_frame_bits(s);
1149
1150
1097
    s->exponent_bits = count_exponent_bits(s);
1151
1152
1097
    bit_alloc_masking(s);
1153
1154
1097
    return cbr_bit_allocation(s);
1155
}
1156
1157
1158
/**
1159
 * Symmetric quantization on 'levels' levels.
1160
 *
1161
 * @param c       unquantized coefficient
1162
 * @param e       exponent
1163
 * @param levels  number of quantization levels
1164
 * @return        quantized coefficient
1165
 */
1166
990113
static inline int sym_quant(int c, int e, int levels)
1167
{
1168
990113
    int v = (((levels * c) >> (24 - e)) + levels) >> 1;
1169
    av_assert2(v >= 0 && v < levels);
1170
990113
    return v;
1171
}
1172
1173
1174
/**
1175
 * Asymmetric quantization on 2^qbits levels.
1176
 *
1177
 * @param c      unquantized coefficient
1178
 * @param e      exponent
1179
 * @param qbits  number of quantization bits
1180
 * @return       quantized coefficient
1181
 */
1182
131749
static inline int asym_quant(int c, int e, int qbits)
1183
{
1184
    int m;
1185
1186
131749
    c = (((c * (1<<e)) >> (24 - qbits)) + 1) >> 1;
1187
131749
    m = (1 << (qbits-1));
1188
131749
    if (c >= m)
1189
147
        c = m - 1;
1190
    av_assert2(c >= -m);
1191
131749
    return c;
1192
}
1193
1194
1195
/**
1196
 * Quantize a set of mantissas for a single channel in a single block.
1197
 *
1198
 * @param s           Mantissa count context
1199
 * @param fixed_coef  unquantized fixed-point coefficients
1200
 * @param exp         exponents
1201
 * @param bap         bit allocation pointer indices
1202
 * @param[out] qmant  quantized coefficients
1203
 * @param start_freq  starting coefficient bin
1204
 * @param end_freq    ending coefficient bin
1205
 */
1206
15210
static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
1207
                                      uint8_t *exp, uint8_t *bap,
1208
                                      int16_t *qmant, int start_freq,
1209
                                      int end_freq)
1210
{
1211
    int i;
1212
1213
1638762
    for (i = start_freq; i < end_freq; i++) {
1214
1623552
        int c = fixed_coef[i];
1215
1623552
        int e = exp[i];
1216
1623552
        int v = bap[i];
1217
1623552
        if (v)
1218


1121862
        switch (v) {
1219
473300
        case 1:
1220
473300
            v = sym_quant(c, e, 3);
1221
473300
            switch (s->mant1_cnt) {
1222
159865
            case 0:
1223
159865
                s->qmant1_ptr = &qmant[i];
1224
159865
                v = 9 * v;
1225
159865
                s->mant1_cnt = 1;
1226
159865
                break;
1227
157814
            case 1:
1228
157814
                *s->qmant1_ptr += 3 * v;
1229
157814
                s->mant1_cnt = 2;
1230
157814
                v = 128;
1231
157814
                break;
1232
155621
            default:
1233
155621
                *s->qmant1_ptr += v;
1234
155621
                s->mant1_cnt = 0;
1235
155621
                v = 128;
1236
155621
                break;
1237
            }
1238
473300
            break;
1239
183360
        case 2:
1240
183360
            v = sym_quant(c, e, 5);
1241
183360
            switch (s->mant2_cnt) {
1242
63147
            case 0:
1243
63147
                s->qmant2_ptr = &qmant[i];
1244
63147
                v = 25 * v;
1245
63147
                s->mant2_cnt = 1;
1246
63147
                break;
1247
61099
            case 1:
1248
61099
                *s->qmant2_ptr += 5 * v;
1249
61099
                s->mant2_cnt = 2;
1250
61099
                v = 128;
1251
61099
                break;
1252
59114
            default:
1253
59114
                *s->qmant2_ptr += v;
1254
59114
                s->mant2_cnt = 0;
1255
59114
                v = 128;
1256
59114
                break;
1257
            }
1258
183360
            break;
1259
191598
        case 3:
1260
191598
            v = sym_quant(c, e, 7);
1261
191598
            break;
1262
84614
        case 4:
1263
84614
            v = sym_quant(c, e, 11);
1264
84614
            switch (s->mant4_cnt) {
1265
43497
            case 0:
1266
43497
                s->qmant4_ptr = &qmant[i];
1267
43497
                v = 11 * v;
1268
43497
                s->mant4_cnt = 1;
1269
43497
                break;
1270
41117
            default:
1271
41117
                *s->qmant4_ptr += v;
1272
41117
                s->mant4_cnt = 0;
1273
41117
                v = 128;
1274
41117
                break;
1275
            }
1276
84614
            break;
1277
57241
        case 5:
1278
57241
            v = sym_quant(c, e, 15);
1279
57241
            break;
1280
        case 14:
1281
            v = asym_quant(c, e, 14);
1282
            break;
1283
        case 15:
1284
            v = asym_quant(c, e, 16);
1285
            break;
1286
131749
        default:
1287
131749
            v = asym_quant(c, e, v - 1);
1288
131749
            break;
1289
        }
1290
1623552
        qmant[i] = v;
1291
    }
1292
15210
}
1293
1294
1295
/**
1296
 * Quantize mantissas using coefficients, exponents, and bit allocation pointers.
1297
 *
1298
 * @param s  AC-3 encoder private context
1299
 */
1300
1097
void ff_ac3_quantize_mantissas(AC3EncodeContext *s)
1301
{
1302
1097
    int blk, ch, ch0=0, got_cpl;
1303
1304
7679
    for (blk = 0; blk < s->num_blocks; blk++) {
1305
6582
        AC3Block *block = &s->blocks[blk];
1306
6582
        AC3Mant m = { 0 };
1307
1308
6582
        got_cpl = !block->cpl_in_use;
1309
21792
        for (ch = 1; ch <= s->channels; ch++) {
1310

15210
            if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1311
4314
                ch0     = ch - 1;
1312
4314
                ch      = CPL_CH;
1313
4314
                got_cpl = 1;
1314
            }
1315
15210
            quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
1316
15210
                                      s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
1317
15210
                                      s->ref_bap[ch][blk], block->qmant[ch],
1318
                                      s->start_freq[ch], block->end_freq[ch]);
1319
15210
            if (ch == CPL_CH)
1320
4314
                ch = ch0;
1321
        }
1322
    }
1323
1097
}
1324
1325
1326
/*
1327
 * Write the AC-3 frame header to the output bitstream.
1328
 */
1329
824
static void ac3_output_frame_header(AC3EncodeContext *s)
1330
{
1331
824
    AC3EncOptions *opt = &s->options;
1332
1333
824
    put_bits(&s->pb, 16, 0x0b77);   /* frame header */
1334
824
    put_bits(&s->pb, 16, 0);        /* crc1: will be filled later */
1335
824
    put_bits(&s->pb, 2,  s->bit_alloc.sr_code);
1336
824
    put_bits(&s->pb, 6,  s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
1337
824
    put_bits(&s->pb, 5,  s->bitstream_id);
1338
824
    put_bits(&s->pb, 3,  s->bitstream_mode);
1339
824
    put_bits(&s->pb, 3,  s->channel_mode);
1340

824
    if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
1341
        put_bits(&s->pb, 2, s->center_mix_level);
1342
824
    if (s->channel_mode & 0x04)
1343
        put_bits(&s->pb, 2, s->surround_mix_level);
1344
824
    if (s->channel_mode == AC3_CHMODE_STEREO)
1345
446
        put_bits(&s->pb, 2, opt->dolby_surround_mode);
1346
824
    put_bits(&s->pb, 1, s->lfe_on); /* LFE */
1347
824
    put_bits(&s->pb, 5, -opt->dialogue_level);
1348
824
    put_bits(&s->pb, 1, 0);         /* no compression control word */
1349
824
    put_bits(&s->pb, 1, 0);         /* no lang code */
1350
824
    put_bits(&s->pb, 1, opt->audio_production_info);
1351
824
    if (opt->audio_production_info) {
1352
        put_bits(&s->pb, 5, opt->mixing_level - 80);
1353
        put_bits(&s->pb, 2, opt->room_type);
1354
    }
1355
824
    put_bits(&s->pb, 1, opt->copyright);
1356
824
    put_bits(&s->pb, 1, opt->original);
1357
824
    if (s->bitstream_id == 6) {
1358
        /* alternate bit stream syntax */
1359
        put_bits(&s->pb, 1, opt->extended_bsi_1);
1360
        if (opt->extended_bsi_1) {
1361
            put_bits(&s->pb, 2, opt->preferred_stereo_downmix);
1362
            put_bits(&s->pb, 3, s->ltrt_center_mix_level);
1363
            put_bits(&s->pb, 3, s->ltrt_surround_mix_level);
1364
            put_bits(&s->pb, 3, s->loro_center_mix_level);
1365
            put_bits(&s->pb, 3, s->loro_surround_mix_level);
1366
        }
1367
        put_bits(&s->pb, 1, opt->extended_bsi_2);
1368
        if (opt->extended_bsi_2) {
1369
            put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);
1370
            put_bits(&s->pb, 2, opt->dolby_headphone_mode);
1371
            put_bits(&s->pb, 1, opt->ad_converter_type);
1372
            put_bits(&s->pb, 9, 0);     /* xbsi2 and encinfo : reserved */
1373
        }
1374
    } else {
1375
824
    put_bits(&s->pb, 1, 0);         /* no time code 1 */
1376
824
    put_bits(&s->pb, 1, 0);         /* no time code 2 */
1377
    }
1378
824
    put_bits(&s->pb, 1, 0);         /* no additional bit stream info */
1379
824
}
1380
1381
1382
/*
1383
 * Write one audio block to the output bitstream.
1384
 */
1385
6582
static void output_audio_block(AC3EncodeContext *s, int blk)
1386
{
1387
6582
    int ch, i, baie, bnd, got_cpl, av_uninit(ch0);
1388
6582
    AC3Block *block = &s->blocks[blk];
1389
1390
    /* block switching */
1391
6582
    if (!s->eac3) {
1392
12564
        for (ch = 0; ch < s->fbw_channels; ch++)
1393
7620
            put_bits(&s->pb, 1, 0);
1394
    }
1395
1396
    /* dither flags */
1397
6582
    if (!s->eac3) {
1398
12564
        for (ch = 0; ch < s->fbw_channels; ch++)
1399
7620
            put_bits(&s->pb, 1, 1);
1400
    }
1401
1402
    /* dynamic range codes */
1403
6582
    put_bits(&s->pb, 1, 0);
1404
1405
    /* spectral extension */
1406
6582
    if (s->eac3)
1407
1638
        put_bits(&s->pb, 1, 0);
1408
1409
    /* channel coupling */
1410
6582
    if (!s->eac3)
1411
4944
        put_bits(&s->pb, 1, block->new_cpl_strategy);
1412
6582
    if (block->new_cpl_strategy) {
1413
1097
        if (!s->eac3)
1414
824
            put_bits(&s->pb, 1, block->cpl_in_use);
1415
1097
        if (block->cpl_in_use) {
1416
            int start_sub, end_sub;
1417
719
            if (s->eac3)
1418
273
                put_bits(&s->pb, 1, 0); /* enhanced coupling */
1419

719
            if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
1420
1338
                for (ch = 1; ch <= s->fbw_channels; ch++)
1421
892
                    put_bits(&s->pb, 1, block->channel_in_cpl[ch]);
1422
            }
1423
719
            if (s->channel_mode == AC3_CHMODE_STEREO)
1424
719
                put_bits(&s->pb, 1, 0); /* phase flags in use */
1425
719
            start_sub = (s->start_freq[CPL_CH] - 37) / 12;
1426
719
            end_sub   = (s->cpl_end_freq       - 37) / 12;
1427
719
            put_bits(&s->pb, 4, start_sub);
1428
719
            put_bits(&s->pb, 4, end_sub - 3);
1429
            /* coupling band structure */
1430
719
            if (s->eac3) {
1431
273
                put_bits(&s->pb, 1, 0); /* use default */
1432
            } else {
1433
2230
                for (bnd = start_sub+1; bnd < end_sub; bnd++)
1434
1784
                    put_bits(&s->pb, 1, ff_eac3_default_cpl_band_struct[bnd]);
1435
            }
1436
        }
1437
    }
1438
1439
    /* coupling coordinates */
1440
6582
    if (block->cpl_in_use) {
1441
12942
        for (ch = 1; ch <= s->fbw_channels; ch++) {
1442
8628
            if (block->channel_in_cpl[ch]) {
1443

8628
                if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1444
8082
                    put_bits(&s->pb, 1, block->new_cpl_coords[ch]);
1445
8628
                if (block->new_cpl_coords[ch]) {
1446
1470
                    put_bits(&s->pb, 2, block->cpl_master_exp[ch]);
1447
7350
                    for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
1448
5880
                        put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);
1449
5880
                        put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]);
1450
                    }
1451
                }
1452
            }
1453
        }
1454
    }
1455
1456
    /* stereo rematrixing */
1457
6582
    if (s->channel_mode == AC3_CHMODE_STEREO) {
1458

4314
        if (!s->eac3 || blk > 0)
1459
4041
            put_bits(&s->pb, 1, block->new_rematrixing_strategy);
1460
4314
        if (block->new_rematrixing_strategy) {
1461
            /* rematrixing flags */
1462
11070
            for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
1463
8856
                put_bits(&s->pb, 1, block->rematrixing_flags[bnd]);
1464
        }
1465
    }
1466
1467
    /* exponent strategy */
1468
6582
    if (!s->eac3) {
1469
15240
        for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
1470
10296
            put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
1471
4944
        if (s->lfe_on)
1472
            put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
1473
    }
1474
1475
    /* bandwidth */
1476
17478
    for (ch = 1; ch <= s->fbw_channels; ch++) {
1477

10896
        if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
1478
1826
            put_bits(&s->pb, 6, s->bandwidth_code);
1479
    }
1480
1481
    /* exponents */
1482
21792
    for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1483
        int nb_groups;
1484
15210
        int cpl = (ch == CPL_CH);
1485
1486
15210
        if (s->exp_strategy[ch][blk] == EXP_REUSE)
1487
8824
            continue;
1488
1489
        /* DC exponent */
1490
6386
        put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl);
1491
1492
        /* exponent groups */
1493
6386
        nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
1494
116287
        for (i = 1; i <= nb_groups; i++)
1495
109901
            put_bits(&s->pb, 7, block->grouped_exp[ch][i]);
1496
1497
        /* gain range info */
1498

6386
        if (ch != s->lfe_channel && !cpl)
1499
4304
            put_bits(&s->pb, 2, 0);
1500
    }
1501
1502
    /* bit allocation info */
1503
6582
    if (!s->eac3) {
1504
4944
        baie = (blk == 0);
1505
4944
        put_bits(&s->pb, 1, baie);
1506
4944
        if (baie) {
1507
824
            put_bits(&s->pb, 2, s->slow_decay_code);
1508
824
            put_bits(&s->pb, 2, s->fast_decay_code);
1509
824
            put_bits(&s->pb, 2, s->slow_gain_code);
1510
824
            put_bits(&s->pb, 2, s->db_per_bit_code);
1511
824
            put_bits(&s->pb, 3, s->floor_code);
1512
        }
1513
    }
1514
1515
    /* snr offset */
1516
6582
    if (!s->eac3) {
1517
4944
        put_bits(&s->pb, 1, block->new_snr_offsets);
1518
4944
        if (block->new_snr_offsets) {
1519
824
            put_bits(&s->pb, 6, s->coarse_snr_offset);
1520
2540
            for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1521
1716
                put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
1522
1716
                put_bits(&s->pb, 3, s->fast_gain_code[ch]);
1523
            }
1524
        }
1525
    } else {
1526
1638
        put_bits(&s->pb, 1, 0); /* no converter snr offset */
1527
    }
1528
1529
    /* coupling leak */
1530
6582
    if (block->cpl_in_use) {
1531

4314
        if (!s->eac3 || block->new_cpl_leak != 2)
1532
4041
            put_bits(&s->pb, 1, block->new_cpl_leak);
1533
4314
        if (block->new_cpl_leak) {
1534
719
            put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak);
1535
719
            put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak);
1536
        }
1537
    }
1538
1539
6582
    if (!s->eac3) {
1540
4944
        put_bits(&s->pb, 1, 0); /* no delta bit allocation */
1541
4944
        put_bits(&s->pb, 1, 0); /* no data to skip */
1542
    }
1543
1544
    /* mantissas */
1545
6582
    got_cpl = !block->cpl_in_use;
1546
21792
    for (ch = 1; ch <= s->channels; ch++) {
1547
        int b, q;
1548
1549

15210
        if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1550
4314
            ch0     = ch - 1;
1551
4314
            ch      = CPL_CH;
1552
4314
            got_cpl = 1;
1553
        }
1554
1638762
        for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
1555
1623552
            q = block->qmant[ch][i];
1556
1623552
            b = s->ref_bap[ch][blk][i];
1557


1623552
            switch (b) {
1558
501690
            case 0:                                          break;
1559
473300
            case 1: if (q != 128) put_bits (&s->pb,   5, q); break;
1560
183360
            case 2: if (q != 128) put_bits (&s->pb,   7, q); break;
1561
191598
            case 3:               put_sbits(&s->pb,   3, q); break;
1562
84614
            case 4: if (q != 128) put_bits (&s->pb,   7, q); break;
1563
            case 14:              put_sbits(&s->pb,  14, q); break;
1564
            case 15:              put_sbits(&s->pb,  16, q); break;
1565
188990
            default:              put_sbits(&s->pb, b-1, q); break;
1566
            }
1567
        }
1568
15210
        if (ch == CPL_CH)
1569
4314
            ch = ch0;
1570
    }
1571
6582
}
1572
1573
1574
/** CRC-16 Polynomial */
1575
#define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
1576
1577
1578
1006
static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
1579
{
1580
    unsigned int c;
1581
1582
1006
    c = 0;
1583
16124
    while (a) {
1584
15118
        if (a & 1)
1585
7198
            c ^= b;
1586
15118
        a = a >> 1;
1587
15118
        b = b << 1;
1588
15118
        if (b & (1 << 16))
1589
7288
            b ^= poly;
1590
    }
1591
1006
    return c;
1592
}
1593
1594
1595
12
static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
1596
{
1597
    unsigned int r;
1598
12
    r = 1;
1599
154
    while (n) {
1600
142
        if (n & 1)
1601
40
            r = mul_poly(r, a, poly);
1602
142
        a = mul_poly(a, a, poly);
1603
142
        n >>= 1;
1604
    }
1605
12
    return r;
1606
}
1607
1608
1609
/*
1610
 * Fill the end of the frame with 0's and compute the two CRCs.
1611
 */
1612
1097
static void output_frame_end(AC3EncodeContext *s)
1613
{
1614
1097
    const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
1615
    int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv;
1616
    uint8_t *frame;
1617
1618
1097
    frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
1619
1620
    /* pad the remainder of the frame with zeros */
1621
    av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18);
1622
1097
    flush_put_bits(&s->pb);
1623
1097
    frame = s->pb.buf;
1624
1097
    pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
1625
    av_assert2(pad_bytes >= 0);
1626
1097
    if (pad_bytes > 0)
1627
975
        memset(put_bits_ptr(&s->pb), 0, pad_bytes);
1628
1629
1097
    if (s->eac3) {
1630
        /* compute crc2 */
1631
273
        crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5);
1632
    } else {
1633
    /* compute crc1 */
1634
    /* this is not so easy because it is at the beginning of the data... */
1635
824
    crc1    = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
1636
824
    crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
1637
824
    crc1    = mul_poly(crc_inv, crc1, CRC16_POLY);
1638
824
    AV_WB16(frame + 2, crc1);
1639
1640
    /* compute crc2 */
1641
824
    crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58,
1642
824
                          s->frame_size - frame_size_58 - 3);
1643
    }
1644
1097
    crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1645
    /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
1646
1097
    if (crc2 == 0x770B) {
1647
        frame[s->frame_size - 3] ^= 0x1;
1648
        crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1649
    }
1650
1097
    crc2 = av_bswap16(crc2);
1651
1097
    AV_WB16(frame + s->frame_size - 2, crc2);
1652
1097
}
1653
1654
1655
/**
1656
 * Write the frame to the output bitstream.
1657
 *
1658
 * @param s      AC-3 encoder private context
1659
 * @param frame  output data buffer
1660
 */
1661
1097
void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
1662
{
1663
    int blk;
1664
1665
1097
    init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);
1666
1667
1097
    s->output_frame_header(s);
1668
1669
7679
    for (blk = 0; blk < s->num_blocks; blk++)
1670
6582
        output_audio_block(s, blk);
1671
1672
1097
    output_frame_end(s);
1673
1097
}
1674
1675
1676
6
static void dprint_options(AC3EncodeContext *s)
1677
{
1678
#ifdef DEBUG
1679
    AVCodecContext *avctx = s->avctx;
1680
    AC3EncOptions *opt = &s->options;
1681
    char strbuf[32];
1682
1683
    switch (s->bitstream_id) {
1684
    case  6:  av_strlcpy(strbuf, "AC-3 (alt syntax)",       32); break;
1685
    case  8:  av_strlcpy(strbuf, "AC-3 (standard)",         32); break;
1686
    case  9:  av_strlcpy(strbuf, "AC-3 (dnet half-rate)",   32); break;
1687
    case 10:  av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break;
1688
    case 16:  av_strlcpy(strbuf, "E-AC-3 (enhanced)",       32); break;
1689
    default: snprintf(strbuf, 32, "ERROR");
1690
    }
1691
    ff_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id);
1692
    ff_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
1693
    av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout);
1694
    ff_dlog(avctx, "channel_layout: %s\n", strbuf);
1695
    ff_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
1696
    ff_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
1697
    ff_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
1698
    if (s->cutoff)
1699
        ff_dlog(avctx, "cutoff: %d\n", s->cutoff);
1700
1701
    ff_dlog(avctx, "per_frame_metadata: %s\n",
1702
            opt->allow_per_frame_metadata?"on":"off");
1703
    if (s->has_center)
1704
        ff_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
1705
                s->center_mix_level);
1706
    else
1707
        ff_dlog(avctx, "center_mixlev: {not written}\n");
1708
    if (s->has_surround)
1709
        ff_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
1710
                s->surround_mix_level);
1711
    else
1712
        ff_dlog(avctx, "surround_mixlev: {not written}\n");
1713
    if (opt->audio_production_info) {
1714
        ff_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
1715
        switch (opt->room_type) {
1716
        case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1717
        case AC3ENC_OPT_LARGE_ROOM:    av_strlcpy(strbuf, "large", 32);        break;
1718
        case AC3ENC_OPT_SMALL_ROOM:    av_strlcpy(strbuf, "small", 32);        break;
1719
        default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type);
1720
        }
1721
        ff_dlog(avctx, "room_type: %s\n", strbuf);
1722
    } else {
1723
        ff_dlog(avctx, "mixing_level: {not written}\n");
1724
        ff_dlog(avctx, "room_type: {not written}\n");
1725
    }
1726
    ff_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
1727
    ff_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
1728
    if (s->channel_mode == AC3_CHMODE_STEREO) {
1729
        switch (opt->dolby_surround_mode) {
1730
        case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1731
        case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
1732
        case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
1733
        default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode);
1734
        }
1735
        ff_dlog(avctx, "dsur_mode: %s\n", strbuf);
1736
    } else {
1737
        ff_dlog(avctx, "dsur_mode: {not written}\n");
1738
    }
1739
    ff_dlog(avctx, "original: %s\n", opt->original?"on":"off");
1740
1741
    if (s->bitstream_id == 6) {
1742
        if (opt->extended_bsi_1) {
1743
            switch (opt->preferred_stereo_downmix) {
1744
            case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1745
            case AC3ENC_OPT_DOWNMIX_LTRT:  av_strlcpy(strbuf, "ltrt", 32);         break;
1746
            case AC3ENC_OPT_DOWNMIX_LORO:  av_strlcpy(strbuf, "loro", 32);         break;
1747
            default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix);
1748
            }
1749
            ff_dlog(avctx, "dmix_mode: %s\n", strbuf);
1750
            ff_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
1751
                    opt->ltrt_center_mix_level, s->ltrt_center_mix_level);
1752
            ff_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
1753
                    opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level);
1754
            ff_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
1755
                    opt->loro_center_mix_level, s->loro_center_mix_level);
1756
            ff_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
1757
                    opt->loro_surround_mix_level, s->loro_surround_mix_level);
1758
        } else {
1759
            ff_dlog(avctx, "extended bitstream info 1: {not written}\n");
1760
        }
1761
        if (opt->extended_bsi_2) {
1762
            switch (opt->dolby_surround_ex_mode) {
1763
            case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1764
            case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
1765
            case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
1766
            default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode);
1767
            }
1768
            ff_dlog(avctx, "dsurex_mode: %s\n", strbuf);
1769
            switch (opt->dolby_headphone_mode) {
1770
            case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1771
            case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
1772
            case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
1773
            default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode);
1774
            }
1775
            ff_dlog(avctx, "dheadphone_mode: %s\n", strbuf);
1776
1777
            switch (opt->ad_converter_type) {
1778
            case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break;
1779
            case AC3ENC_OPT_ADCONV_HDCD:     av_strlcpy(strbuf, "hdcd", 32);     break;
1780
            default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type);
1781
            }
1782
            ff_dlog(avctx, "ad_conv_type: %s\n", strbuf);
1783
        } else {
1784
            ff_dlog(avctx, "extended bitstream info 2: {not written}\n");
1785
        }
1786
    }
1787
#endif
1788
6
}
1789
1790
1791
#define FLT_OPTION_THRESHOLD 0.01
1792
1793
static int validate_float_option(float v, const float *v_list, int v_list_size)
1794
{
1795
    int i;
1796
1797
    for (i = 0; i < v_list_size; i++) {
1798
        if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
1799
            v > (v_list[i] - FLT_OPTION_THRESHOLD))
1800
            break;
1801
    }
1802
    if (i == v_list_size)
1803
        return AVERROR(EINVAL);
1804
1805
    return i;
1806
}
1807
1808
1809
static void validate_mix_level(void *log_ctx, const char *opt_name,
1810
                               float *opt_param, const float *list,
1811
                               int list_size, int default_value, int min_value,
1812
                               int *ctx_param)
1813
{
1814
    int mixlev = validate_float_option(*opt_param, list, list_size);
1815
    if (mixlev < min_value) {
1816
        mixlev = default_value;
1817
        if (*opt_param >= 0.0) {
1818
            av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
1819
                   "default value: %0.3f\n", opt_name, list[mixlev]);
1820
        }
1821
    }
1822
    *opt_param = list[mixlev];
1823
    *ctx_param = mixlev;
1824
}
1825
1826
1827
/**
1828
 * Validate metadata options as set by AVOption system.
1829
 * These values can optionally be changed per-frame.
1830
 *
1831
 * @param s  AC-3 encoder private context
1832
 */
1833
6
int ff_ac3_validate_metadata(AC3EncodeContext *s)
1834
{
1835
6
    AVCodecContext *avctx = s->avctx;
1836
6
    AC3EncOptions *opt = &s->options;
1837
1838
6
    opt->audio_production_info = 0;
1839
6
    opt->extended_bsi_1        = 0;
1840
6
    opt->extended_bsi_2        = 0;
1841
6
    opt->eac3_mixing_metadata  = 0;
1842
6
    opt->eac3_info_metadata    = 0;
1843
1844
    /* determine mixing metadata / xbsi1 use */
1845

6
    if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) {
1846
        opt->extended_bsi_1       = 1;
1847
        opt->eac3_mixing_metadata = 1;
1848
    }
1849
6
    if (s->has_center &&
1850
        (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
1851
        opt->extended_bsi_1       = 1;
1852
        opt->eac3_mixing_metadata = 1;
1853
    }
1854
6
    if (s->has_surround &&
1855
        (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
1856
        opt->extended_bsi_1       = 1;
1857
        opt->eac3_mixing_metadata = 1;
1858
    }
1859
1860
6
    if (s->eac3) {
1861
        /* determine info metadata use */
1862
1
        if (avctx->audio_service_type != AV_AUDIO_SERVICE_TYPE_MAIN)
1863
            opt->eac3_info_metadata = 1;
1864

1
        if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
1865
            opt->eac3_info_metadata = 1;
1866
1
        if (s->channel_mode == AC3_CHMODE_STEREO &&
1867

1
            (opt->dolby_headphone_mode != AC3ENC_OPT_NONE || opt->dolby_surround_mode != AC3ENC_OPT_NONE))
1868
            opt->eac3_info_metadata = 1;
1869

1
        if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
1870
            opt->eac3_info_metadata = 1;
1871

1
        if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
1872
1
            opt->ad_converter_type != AC3ENC_OPT_NONE) {
1873
            opt->audio_production_info = 1;
1874
            opt->eac3_info_metadata    = 1;
1875
        }
1876
    } else {
1877
        /* determine audio production info use */
1878

5
        if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
1879
            opt->audio_production_info = 1;
1880
1881
        /* determine xbsi2 use */
1882

5
        if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
1883
            opt->extended_bsi_2 = 1;
1884

5
        if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE)
1885
            opt->extended_bsi_2 = 1;
1886
5
        if (opt->ad_converter_type != AC3ENC_OPT_NONE)
1887
            opt->extended_bsi_2 = 1;
1888
    }
1889
1890
    /* validate AC-3 mixing levels */
1891
6
    if (!s->eac3) {
1892
5
        if (s->has_center) {
1893
            validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
1894
                            cmixlev_options, CMIXLEV_NUM_OPTIONS, 1, 0,
1895
                            &s->center_mix_level);
1896
        }
1897
5
        if (s->has_surround) {
1898
            validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
1899
                            surmixlev_options, SURMIXLEV_NUM_OPTIONS, 1, 0,
1900
                            &s->surround_mix_level);
1901
        }
1902
    }
1903
1904
    /* validate extended bsi 1 / mixing metadata */
1905

6
    if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
1906
        /* default preferred stereo downmix */
1907
        if (opt->preferred_stereo_downmix == AC3ENC_OPT_NONE)
1908
            opt->preferred_stereo_downmix = AC3ENC_OPT_NOT_INDICATED;
1909
        if (!s->eac3 || s->has_center) {
1910
            /* validate Lt/Rt center mix level */
1911
            validate_mix_level(avctx, "ltrt_center_mix_level",
1912
                               &opt->ltrt_center_mix_level, extmixlev_options,
1913
                               EXTMIXLEV_NUM_OPTIONS, 5, 0,
1914
                               &s->ltrt_center_mix_level);
1915
            /* validate Lo/Ro center mix level */
1916
            validate_mix_level(avctx, "loro_center_mix_level",
1917
                               &opt->loro_center_mix_level, extmixlev_options,
1918
                               EXTMIXLEV_NUM_OPTIONS, 5, 0,
1919
                               &s->loro_center_mix_level);
1920
        }
1921
        if (!s->eac3 || s->has_surround) {
1922
            /* validate Lt/Rt surround mix level */
1923
            validate_mix_level(avctx, "ltrt_surround_mix_level",
1924
                               &opt->ltrt_surround_mix_level, extmixlev_options,
1925
                               EXTMIXLEV_NUM_OPTIONS, 6, 3,
1926
                               &s->ltrt_surround_mix_level);
1927
            /* validate Lo/Ro surround mix level */
1928
            validate_mix_level(avctx, "loro_surround_mix_level",
1929
                               &opt->loro_surround_mix_level, extmixlev_options,
1930
                               EXTMIXLEV_NUM_OPTIONS, 6, 3,
1931
                               &s->loro_surround_mix_level);
1932
        }
1933
    }
1934
1935
    /* validate audio service type / channels combination */
1936
6
    if ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_KARAOKE &&
1937
         avctx->channels == 1) ||
1938
6
        ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_COMMENTARY ||
1939
6
          avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_EMERGENCY  ||
1940
6
          avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_VOICE_OVER)
1941
         && avctx->channels > 1)) {
1942
        av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
1943
                                    "specified number of channels\n");
1944
        return AVERROR(EINVAL);
1945
    }
1946
1947
    /* validate extended bsi 2 / info metadata */
1948

6
    if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
1949
        /* default dolby headphone mode */
1950
        if (opt->dolby_headphone_mode == AC3ENC_OPT_NONE)
1951
            opt->dolby_headphone_mode = AC3ENC_OPT_NOT_INDICATED;
1952
        /* default dolby surround ex mode */
1953
        if (opt->dolby_surround_ex_mode == AC3ENC_OPT_NONE)
1954
            opt->dolby_surround_ex_mode = AC3ENC_OPT_NOT_INDICATED;
1955
        /* default A/D converter type */
1956
        if (opt->ad_converter_type == AC3ENC_OPT_NONE)
1957
            opt->ad_converter_type = AC3ENC_OPT_ADCONV_STANDARD;
1958
    }
1959
1960
    /* copyright & original defaults */
1961

6
    if (!s->eac3 || opt->eac3_info_metadata) {
1962
        /* default copyright */
1963
5
        if (opt->copyright == AC3ENC_OPT_NONE)
1964
5
            opt->copyright = AC3ENC_OPT_OFF;
1965
        /* default original */
1966
5
        if (opt->original == AC3ENC_OPT_NONE)
1967
5
            opt->original = AC3ENC_OPT_ON;
1968
    }
1969
1970
    /* dolby surround mode default */
1971

6
    if (!s->eac3 || opt->eac3_info_metadata) {
1972
5
        if (opt->dolby_surround_mode == AC3ENC_OPT_NONE)
1973
5
            opt->dolby_surround_mode = AC3ENC_OPT_NOT_INDICATED;
1974
    }
1975
1976
    /* validate audio production info */
1977
6
    if (opt->audio_production_info) {
1978
        if (opt->mixing_level == AC3ENC_OPT_NONE) {
1979
            av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
1980
                   "room_type is set\n");
1981
            return AVERROR(EINVAL);
1982
        }
1983
        if (opt->mixing_level < 80) {
1984
            av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
1985
                   "80dB and 111dB\n");
1986
            return AVERROR(EINVAL);
1987
        }
1988
        /* default room type */
1989
        if (opt->room_type == AC3ENC_OPT_NONE)
1990
            opt->room_type = AC3ENC_OPT_NOT_INDICATED;
1991
    }
1992
1993
    /* set bitstream id for alternate bitstream syntax */
1994

6
    if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {
1995
        if (s->bitstream_id > 8 && s->bitstream_id < 11) {
1996
            static int warn_once = 1;
1997
            if (warn_once) {
1998
                av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "
1999
                       "not compatible with reduced samplerates. writing of "
2000
                       "extended bitstream information will be disabled.\n");
2001
                warn_once = 0;
2002
            }
2003
        } else {
2004
            s->bitstream_id = 6;
2005
        }
2006
    }
2007
2008
6
    return 0;
2009
}
2010
2011
2012
/**
2013
 * Finalize encoding and free any memory allocated by the encoder.
2014
 *
2015
 * @param avctx  Codec context
2016
 */
2017
6
av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
2018
{
2019
    int blk, ch;
2020
6
    AC3EncodeContext *s = avctx->priv_data;
2021
2022
6
    av_freep(&s->windowed_samples);
2023
6
    if (s->planar_samples)
2024
15
    for (ch = 0; ch < s->channels; ch++)
2025
9
        av_freep(&s->planar_samples[ch]);
2026
6
    av_freep(&s->planar_samples);
2027
6
    av_freep(&s->bap_buffer);
2028
6
    av_freep(&s->bap1_buffer);
2029
6
    av_freep(&s->mdct_coef_buffer);
2030
6
    av_freep(&s->fixed_coef_buffer);
2031
6
    av_freep(&s->exp_buffer);
2032
6
    av_freep(&s->grouped_exp_buffer);
2033
6
    av_freep(&s->psd_buffer);
2034
6
    av_freep(&s->band_psd_buffer);
2035
6
    av_freep(&s->mask_buffer);
2036
6
    av_freep(&s->qmant_buffer);
2037
6
    av_freep(&s->cpl_coord_exp_buffer);
2038
6
    av_freep(&s->cpl_coord_mant_buffer);
2039
6
    av_freep(&s->fdsp);
2040
42
    for (blk = 0; blk < s->num_blocks; blk++) {
2041
36
        AC3Block *block = &s->blocks[blk];
2042
36
        av_freep(&block->mdct_coef);
2043
36
        av_freep(&block->fixed_coef);
2044
36
        av_freep(&block->exp);
2045
36
        av_freep(&block->grouped_exp);
2046
36
        av_freep(&block->psd);
2047
36
        av_freep(&block->band_psd);
2048
36
        av_freep(&block->mask);
2049
36
        av_freep(&block->qmant);
2050
36
        av_freep(&block->cpl_coord_exp);
2051
36
        av_freep(&block->cpl_coord_mant);
2052
    }
2053
2054
6
    if (s->mdct_end)
2055
6
        s->mdct_end(s);
2056
2057
6
    return 0;
2058
}
2059
2060
2061
/*
2062
 * Set channel information during initialization.
2063
 */
2064
6
static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
2065
                                    uint64_t *channel_layout)
2066
{
2067
    int ch_layout;
2068
2069

6
    if (channels < 1 || channels > AC3_MAX_CHANNELS)
2070
        return AVERROR(EINVAL);
2071
6
    if (*channel_layout > 0x7FF)
2072
        return AVERROR(EINVAL);
2073
6
    ch_layout = *channel_layout;
2074
6
    if (!ch_layout)
2075
        ch_layout = av_get_default_channel_layout(channels);
2076
2077
6
    s->lfe_on       = !!(ch_layout & AV_CH_LOW_FREQUENCY);
2078
6
    s->channels     = channels;
2079
6
    s->fbw_channels = channels - s->lfe_on;
2080
6
    s->lfe_channel  = s->lfe_on ? s->fbw_channels + 1 : -1;
2081
6
    if (s->lfe_on)
2082
        ch_layout -= AV_CH_LOW_FREQUENCY;
2083
2084


6
    switch (ch_layout) {
2085
3
    case AV_CH_LAYOUT_MONO:           s->channel_mode = AC3_CHMODE_MONO;   break;
2086
3
    case AV_CH_LAYOUT_STEREO:         s->channel_mode = AC3_CHMODE_STEREO; break;
2087
    case AV_CH_LAYOUT_SURROUND:       s->channel_mode = AC3_CHMODE_3F;     break;
2088
    case AV_CH_LAYOUT_2_1:            s->channel_mode = AC3_CHMODE_2F1R;   break;
2089
    case AV_CH_LAYOUT_4POINT0:        s->channel_mode = AC3_CHMODE_3F1R;   break;
2090
    case AV_CH_LAYOUT_QUAD:
2091
    case AV_CH_LAYOUT_2_2:            s->channel_mode = AC3_CHMODE_2F2R;   break;
2092
    case AV_CH_LAYOUT_5POINT0:
2093
    case AV_CH_LAYOUT_5POINT0_BACK:   s->channel_mode = AC3_CHMODE_3F2R;   break;
2094
    default:
2095
        return AVERROR(EINVAL);
2096
    }
2097

6
    s->has_center   = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
2098
6
    s->has_surround =  s->channel_mode & 0x04;
2099
2100
6
    s->channel_map  = ff_ac3_enc_channel_map[s->channel_mode][s->lfe_on];
2101
6
    *channel_layout = ch_layout;
2102
6
    if (s->lfe_on)
2103
        *channel_layout |= AV_CH_LOW_FREQUENCY;
2104
2105
6
    return 0;
2106
}
2107
2108
2109
6
static av_cold int validate_options(AC3EncodeContext *s)
2110
{
2111
6
    AVCodecContext *avctx = s->avctx;
2112
    int i, ret, max_sr;
2113
2114
    /* validate channel layout */
2115
6
    if (!avctx->channel_layout) {
2116
        av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "
2117
                                      "encoder will guess the layout, but it "
2118
                                      "might be incorrect.\n");
2119
    }
2120
6
    ret = set_channel_info(s, avctx->channels, &avctx->channel_layout);
2121
6
    if (ret) {
2122
        av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");
2123
        return ret;
2124
    }
2125
2126
    /* validate sample rate */
2127
    /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a
2128
             decoder that supports half sample rate so we can validate that
2129
             the generated files are correct. */
2130
6
    max_sr = s->eac3 ? 2 : 8;
2131
12
    for (i = 0; i <= max_sr; i++) {
2132
12
        if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)
2133
6
            break;
2134
    }
2135
6
    if (i > max_sr) {
2136
        av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
2137
        return AVERROR(EINVAL);
2138
    }
2139
6
    s->sample_rate        = avctx->sample_rate;
2140
6
    s->bit_alloc.sr_shift = i / 3;
2141
6
    s->bit_alloc.sr_code  = i % 3;
2142
6
    s->bitstream_id       = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;
2143
2144
    /* select a default bit rate if not set by the user */
2145
6
    if (!avctx->bit_rate) {
2146

2
        switch (s->fbw_channels) {
2147
2
        case 1: avctx->bit_rate =  96000; break;
2148
        case 2: avctx->bit_rate = 192000; break;
2149
        case 3: avctx->bit_rate = 320000; break;
2150
        case 4: avctx->bit_rate = 384000; break;
2151
        case 5: avctx->bit_rate = 448000; break;
2152
        }
2153
4
    }
2154
2155
    /* validate bit rate */
2156
6
    if (s->eac3) {
2157
        int max_br, min_br, wpf, min_br_code;
2158
        int num_blks_code, num_blocks, frame_samples;
2159
        long long min_br_dist;
2160
2161
        /* calculate min/max bitrate */
2162
        /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
2163
                 found use either 6 blocks or 1 block, even though 2 or 3 blocks
2164
                 would work as far as the bit rate is concerned. */
2165
1
        for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
2166
1
            num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
2167
1
            frame_samples  = AC3_BLOCK_SIZE * num_blocks;
2168
1
            max_br = 2048 * s->sample_rate / frame_samples * 16;
2169
1
            min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
2170
1
            if (avctx->bit_rate <= max_br)
2171
1
                break;
2172
        }
2173

1
        if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
2174
            av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
2175
                   "for this sample rate\n", min_br, max_br);
2176
            return AVERROR(EINVAL);
2177
        }
2178
1
        s->num_blks_code = num_blks_code;
2179
1
        s->num_blocks    = num_blocks;
2180
2181
        /* calculate words-per-frame for the selected bitrate */
2182
1
        wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
2183
        av_assert1(wpf > 0 && wpf <= 2048);
2184
2185
        /* find the closest AC-3 bitrate code to the selected bitrate.
2186
           this is needed for lookup tables for bandwidth and coupling
2187
           parameter selection */
2188
1
        min_br_code = -1;
2189
1
        min_br_dist = INT64_MAX;
2190
20
        for (i = 0; i < 19; i++) {
2191
19
            long long br_dist = llabs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
2192
19
            if (br_dist < min_br_dist) {
2193
9
                min_br_dist = br_dist;
2194
9
                min_br_code = i;
2195
            }
2196
        }
2197
2198
        /* make sure the minimum frame size is below the average frame size */
2199
1
        s->frame_size_code = min_br_code << 1;
2200

1
        while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
2201
            wpf--;
2202
1
        s->frame_size_min = 2 * wpf;
2203
    } else {
2204
5
        int best_br = 0, best_code = 0;
2205
5
        long long best_diff = INT64_MAX;
2206
37
        for (i = 0; i < 19; i++) {
2207
37
            int br   = (ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift) * 1000;
2208
37
            long long diff = llabs(br - avctx->bit_rate);
2209
37
            if (diff < best_diff) {
2210
37
                best_br   = br;
2211
37
                best_code = i;
2212
37
                best_diff = diff;
2213
            }
2214
37
            if (!best_diff)
2215
5
                break;
2216
        }
2217
5
        avctx->bit_rate    = best_br;
2218
5
        s->frame_size_code = best_code << 1;
2219
5
        s->frame_size_min  = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
2220
5
        s->num_blks_code   = 0x3;
2221
5
        s->num_blocks      = 6;
2222
    }
2223
6
    s->bit_rate   = avctx->bit_rate;
2224
6
    s->frame_size = s->frame_size_min;
2225
2226
    /* validate cutoff */
2227
6
    if (avctx->cutoff < 0) {
2228
        av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
2229
        return AVERROR(EINVAL);
2230
    }
2231
6
    s->cutoff = avctx->cutoff;
2232
6
    if (s->cutoff > (s->sample_rate >> 1))
2233
        s->cutoff = s->sample_rate >> 1;
2234
2235
6
    ret = ff_ac3_validate_metadata(s);
2236
6
    if (ret)
2237
        return ret;
2238
2239
12
    s->rematrixing_enabled = s->options.stereo_rematrixing &&
2240
6
                             (s->channel_mode == AC3_CHMODE_STEREO);
2241
2242
12
    s->cpl_enabled = s->options.channel_coupling &&
2243
6
                     s->channel_mode >= AC3_CHMODE_STEREO;
2244
2245
6
    return 0;
2246
}
2247
2248
2249
/*
2250
 * Set bandwidth for all channels.
2251
 * The user can optionally supply a cutoff frequency. Otherwise an appropriate
2252
 * default value will be used.
2253
 */
2254
6
static av_cold void set_bandwidth(AC3EncodeContext *s)
2255
{
2256
6
    int blk, ch, av_uninit(cpl_start);
2257
2258
6
    if (s->cutoff) {
2259
        /* calculate bandwidth based on user-specified cutoff frequency */
2260
        int fbw_coeffs;
2261
        fbw_coeffs     = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
2262
        s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
2263
    } else {
2264
        /* use default bandwidth setting */
2265
6
        s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
2266
    }
2267
2268
    /* set number of coefficients for each channel */
2269
15
    for (ch = 1; ch <= s->fbw_channels; ch++) {
2270
9
        s->start_freq[ch] = 0;
2271
63
        for (blk = 0; blk < s->num_blocks; blk++)
2272
54
            s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
2273
    }
2274
    /* LFE channel always has 7 coefs */
2275
6
    if (s->lfe_on) {
2276
        s->start_freq[s->lfe_channel] = 0;
2277
        for (blk = 0; blk < s->num_blocks; blk++)
2278
            s->blocks[blk].end_freq[ch] = 7;
2279
    }
2280
2281
    /* initialize coupling strategy */
2282
6
    if (s->cpl_enabled) {
2283
3
        if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
2284
            cpl_start = s->options.cpl_start;
2285
        } else {
2286
3
            cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
2287
3
            if (cpl_start < 0) {
2288
                if (s->options.channel_coupling == AC3ENC_OPT_AUTO)
2289
                    s->cpl_enabled = 0;
2290
                else
2291
                    cpl_start = 15;
2292
            }
2293
        }
2294
    }
2295
6
    if (s->cpl_enabled) {
2296
        int i, cpl_start_band, cpl_end_band;
2297
3
        uint8_t *cpl_band_sizes = s->cpl_band_sizes;
2298
2299
3
        cpl_end_band   = s->bandwidth_code / 4 + 3;
2300
3
        cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
2301
2302
3
        s->num_cpl_subbands = cpl_end_band - cpl_start_band;
2303
2304
3
        s->num_cpl_bands = 1;
2305
3
        *cpl_band_sizes  = 12;
2306
15
        for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
2307
12
            if (ff_eac3_default_cpl_band_struct[i]) {
2308
3
                *cpl_band_sizes += 12;
2309
            } else {
2310
9
                s->num_cpl_bands++;
2311
9
                cpl_band_sizes++;
2312
9
                *cpl_band_sizes = 12;
2313
            }
2314
        }
2315
2316
3
        s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
2317
3
        s->cpl_end_freq       = cpl_end_band   * 12 + 37;
2318
21
        for (blk = 0; blk < s->num_blocks; blk++)
2319
18
            s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
2320
    }
2321
6
}
2322
2323
2324
6
static av_cold int allocate_buffers(AC3EncodeContext *s)
2325
{
2326
6
    AVCodecContext *avctx = s->avctx;
2327
    int blk, ch;
2328
6
    int channels = s->channels + 1; /* includes coupling channel */
2329
6
    int channel_blocks = channels * s->num_blocks;
2330
6
    int total_coefs    = AC3_MAX_COEFS * channel_blocks;
2331
2332
6
    if (s->allocate_sample_buffers(s))
2333
        goto alloc_fail;
2334
2335
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->bap_buffer, total_coefs,
2336
                     sizeof(*s->bap_buffer), alloc_fail);
2337
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->bap1_buffer, total_coefs,
2338
                     sizeof(*s->bap1_buffer), alloc_fail);
2339
6
    FF_ALLOCZ_ARRAY_OR_GOTO(avctx, s->mdct_coef_buffer, total_coefs,
2340
                      sizeof(*s->mdct_coef_buffer), alloc_fail);
2341
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->exp_buffer, total_coefs,
2342
                     sizeof(*s->exp_buffer), alloc_fail);
2343
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->grouped_exp_buffer, channel_blocks, 128 *
2344
                     sizeof(*s->grouped_exp_buffer), alloc_fail);
2345
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->psd_buffer, total_coefs,
2346
                     sizeof(*s->psd_buffer), alloc_fail);
2347
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->band_psd_buffer, channel_blocks, 64 *
2348
                     sizeof(*s->band_psd_buffer), alloc_fail);
2349
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->mask_buffer, channel_blocks, 64 *
2350
                     sizeof(*s->mask_buffer), alloc_fail);
2351
6
    FF_ALLOC_ARRAY_OR_GOTO(avctx, s->qmant_buffer, total_coefs,
2352
                     sizeof(*s->qmant_buffer), alloc_fail);
2353
6
    if (s->cpl_enabled) {
2354
3
        FF_ALLOC_ARRAY_OR_GOTO(avctx, s->cpl_coord_exp_buffer, channel_blocks, 16 *
2355
                         sizeof(*s->cpl_coord_exp_buffer), alloc_fail);
2356
3
        FF_ALLOC_ARRAY_OR_GOTO(avctx, s->cpl_coord_mant_buffer, channel_blocks, 16 *
2357
                         sizeof(*s->cpl_coord_mant_buffer), alloc_fail);
2358
    }
2359
42
    for (blk = 0; blk < s->num_blocks; blk++) {
2360
36
        AC3Block *block = &s->blocks[blk];
2361
36
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->mdct_coef, channels, sizeof(*block->mdct_coef),
2362
                          alloc_fail);
2363
36
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->exp, channels, sizeof(*block->exp),
2364
                          alloc_fail);
2365
36
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->grouped_exp, channels, sizeof(*block->grouped_exp),
2366
                          alloc_fail);
2367
36
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->psd, channels, sizeof(*block->psd),
2368
                          alloc_fail);
2369
36
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->band_psd, channels, sizeof(*block->band_psd),
2370
                          alloc_fail);
2371
36
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->mask, channels, sizeof(*block->mask),
2372
                          alloc_fail);
2373
36
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->qmant, channels, sizeof(*block->qmant),
2374
                          alloc_fail);
2375
36
        if (s->cpl_enabled) {
2376
18
            FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->cpl_coord_exp, channels, sizeof(*block->cpl_coord_exp),
2377
                              alloc_fail);
2378
18
            FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->cpl_coord_mant, channels, sizeof(*block->cpl_coord_mant),
2379
                              alloc_fail);
2380
        }
2381
2382
126
        for (ch = 0; ch < channels; ch++) {
2383
            /* arrangement: block, channel, coeff */
2384
90
            block->grouped_exp[ch] = &s->grouped_exp_buffer[128           * (blk * channels + ch)];
2385
90
            block->psd[ch]         = &s->psd_buffer        [AC3_MAX_COEFS * (blk * channels + ch)];
2386
90
            block->band_psd[ch]    = &s->band_psd_buffer   [64            * (blk * channels + ch)];
2387
90
            block->mask[ch]        = &s->mask_buffer       [64            * (blk * channels + ch)];
2388
90
            block->qmant[ch]       = &s->qmant_buffer      [AC3_MAX_COEFS * (blk * channels + ch)];
2389
90
            if (s->cpl_enabled) {
2390
54
                block->cpl_coord_exp[ch]  = &s->cpl_coord_exp_buffer [16  * (blk * channels + ch)];
2391
54
                block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16  * (blk * channels + ch)];
2392
            }
2393
2394
            /* arrangement: channel, block, coeff */
2395
90
            block->exp[ch]         = &s->exp_buffer        [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2396
90
            block->mdct_coef[ch]   = &s->mdct_coef_buffer  [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2397
        }
2398
    }
2399
2400
6
    if (!s->fixed_point) {
2401
2
        FF_ALLOCZ_ARRAY_OR_GOTO(avctx, s->fixed_coef_buffer, total_coefs,
2402
                          sizeof(*s->fixed_coef_buffer), alloc_fail);
2403
14
        for (blk = 0; blk < s->num_blocks; blk++) {
2404
12
            AC3Block *block = &s->blocks[blk];
2405
12
            FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->fixed_coef, channels,
2406
                              sizeof(*block->fixed_coef), alloc_fail);
2407
48
            for (ch = 0; ch < channels; ch++)
2408
36
                block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2409
        }
2410
    } else {
2411
28
        for (blk = 0; blk < s->num_blocks; blk++) {
2412
24
            AC3Block *block = &s->blocks[blk];
2413
24
            FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->fixed_coef, channels,
2414
                              sizeof(*block->fixed_coef), alloc_fail);
2415
78
            for (ch = 0; ch < channels; ch++)
2416
54
                block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
2417
        }
2418
    }
2419
2420
6
    return 0;
2421
alloc_fail:
2422
    return AVERROR(ENOMEM);
2423
}
2424
2425
2426
6
av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
2427
{
2428
6
    AC3EncodeContext *s = avctx->priv_data;
2429
    int ret, frame_size_58;
2430
2431
6
    s->avctx = avctx;
2432
2433
6
    s->eac3 = avctx->codec_id == AV_CODEC_ID_EAC3;
2434
2435
6
    ret = validate_options(s);
2436
6
    if (ret)
2437
        goto init_fail;
2438
2439
6
    avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
2440
6
    avctx->initial_padding = AC3_BLOCK_SIZE;
2441
2442
6
    s->bitstream_mode = avctx->audio_service_type;
2443
6
    if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE)
2444
        s->bitstream_mode = 0x7;
2445
2446
6
    s->bits_written    = 0;
2447
6
    s->samples_written = 0;
2448
2449
    /* calculate crc_inv for both possible frame sizes */
2450
6
    frame_size_58 = (( s->frame_size    >> 2) + ( s->frame_size    >> 4)) << 1;
2451
6
    s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2452
6
    if (s->bit_alloc.sr_code == 1) {
2453
6
        frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
2454
6
        s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2455
    }
2456
2457
    /* set function pointers */
2458
6
    if (CONFIG_AC3_FIXED_ENCODER && s->fixed_point) {
2459
4
        s->mdct_end                     = ff_ac3_fixed_mdct_end;
2460
4
        s->mdct_init                    = ff_ac3_fixed_mdct_init;
2461
4
        s->allocate_sample_buffers      = ff_ac3_fixed_allocate_sample_buffers;
2462
    } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {
2463
2
        s->mdct_end                     = ff_ac3_float_mdct_end;
2464
2
        s->mdct_init                    = ff_ac3_float_mdct_init;
2465
2
        s->allocate_sample_buffers      = ff_ac3_float_allocate_sample_buffers;
2466
    }
2467
6
    if (CONFIG_EAC3_ENCODER && s->eac3)
2468
1
        s->output_frame_header = ff_eac3_output_frame_header;
2469
    else
2470
5
        s->output_frame_header = ac3_output_frame_header;
2471
2472
6
    set_bandwidth(s);
2473
2474
6
    exponent_init(s);
2475
2476
6
    bit_alloc_init(s);
2477
2478
6
    ret = s->mdct_init(s);
2479
6
    if (ret)
2480
        goto init_fail;
2481
2482
6
    ret = allocate_buffers(s);
2483
6
    if (ret)
2484
        goto init_fail;
2485
2486
6
    ff_audiodsp_init(&s->adsp);
2487
6
    ff_me_cmp_init(&s->mecc, avctx);
2488
6
    ff_ac3dsp_init(&s->ac3dsp, avctx->flags & AV_CODEC_FLAG_BITEXACT);
2489
2490
6
    dprint_options(s);
2491
2492
6
    return 0;
2493
init_fail:
2494
    ff_ac3_encode_close(avctx);
2495
    return ret;
2496
}