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 Libav.
8 *
9 * Libav 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 * Libav 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 Libav; 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//#define ASSERT_LEVEL 2
30
31#include <stdint.h>
32
33#include "libavutil/audioconvert.h"
34#include "libavutil/avassert.h"
35#include "libavutil/avstring.h"
36#include "libavutil/crc.h"
37#include "libavutil/opt.h"
38#include "avcodec.h"
39#include "put_bits.h"
40#include "dsputil.h"
41#include "ac3dsp.h"
42#include "ac3.h"
43#include "audioconvert.h"
44#include "fft.h"
45#include "ac3enc.h"
46#include "eac3enc.h"
47
48typedef struct AC3Mant {
49    int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
50    int mant1_cnt, mant2_cnt, mant4_cnt;    ///< mantissa counts for bap=1,2,4
51} AC3Mant;
52
53#define CMIXLEV_NUM_OPTIONS 3
54static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
55    LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB
56};
57
58#define SURMIXLEV_NUM_OPTIONS 3
59static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS] = {
60    LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO
61};
62
63#define EXTMIXLEV_NUM_OPTIONS 8
64static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS] = {
65    LEVEL_PLUS_3DB,  LEVEL_PLUS_1POINT5DB,  LEVEL_ONE,       LEVEL_MINUS_4POINT5DB,
66    LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB, LEVEL_ZERO
67};
68
69
70/**
71 * LUT for number of exponent groups.
72 * exponent_group_tab[coupling][exponent strategy-1][number of coefficients]
73 */
74static uint8_t exponent_group_tab[2][3][256];
75
76
77/**
78 * List of supported channel layouts.
79 */
80const uint64_t ff_ac3_channel_layouts[19] = {
81     AV_CH_LAYOUT_MONO,
82     AV_CH_LAYOUT_STEREO,
83     AV_CH_LAYOUT_2_1,
84     AV_CH_LAYOUT_SURROUND,
85     AV_CH_LAYOUT_2_2,
86     AV_CH_LAYOUT_QUAD,
87     AV_CH_LAYOUT_4POINT0,
88     AV_CH_LAYOUT_5POINT0,
89     AV_CH_LAYOUT_5POINT0_BACK,
90    (AV_CH_LAYOUT_MONO     | AV_CH_LOW_FREQUENCY),
91    (AV_CH_LAYOUT_STEREO   | AV_CH_LOW_FREQUENCY),
92    (AV_CH_LAYOUT_2_1      | AV_CH_LOW_FREQUENCY),
93    (AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY),
94    (AV_CH_LAYOUT_2_2      | AV_CH_LOW_FREQUENCY),
95    (AV_CH_LAYOUT_QUAD     | AV_CH_LOW_FREQUENCY),
96    (AV_CH_LAYOUT_4POINT0  | AV_CH_LOW_FREQUENCY),
97     AV_CH_LAYOUT_5POINT1,
98     AV_CH_LAYOUT_5POINT1_BACK,
99     0
100};
101
102
103/**
104 * LUT to select the bandwidth code based on the bit rate, sample rate, and
105 * number of full-bandwidth channels.
106 * bandwidth_tab[fbw_channels-1][sample rate code][bit rate code]
107 */
108static const uint8_t ac3_bandwidth_tab[5][3][19] = {
109//      32  40  48  56  64  80  96 112 128 160 192 224 256 320 384 448 512 576 640
110
111    { {  0,  0,  0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
112      {  0,  0,  0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
113      {  0,  0,  0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
114
115    { {  0,  0,  0,  0,  0,  0,  0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
116      {  0,  0,  0,  0,  0,  0,  4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
117      {  0,  0,  0,  0,  0,  0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
118
119    { {  0,  0,  0,  0,  0,  0,  0,  0,  0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
120      {  0,  0,  0,  0,  0,  0,  0,  0,  4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
121      {  0,  0,  0,  0,  0,  0,  0,  0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
122
123    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
124      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
125      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
126
127    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  8, 20, 32, 40, 48, 48, 48, 48 },
128      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 12, 24, 36, 44, 56, 56, 56, 56 },
129      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 28, 44, 60, 60, 60, 60, 60, 60 } }
130};
131
132
133/**
134 * LUT to select the coupling start band based on the bit rate, sample rate, and
135 * number of full-bandwidth channels. -1 = coupling off
136 * ac3_coupling_start_tab[channel_mode-2][sample rate code][bit rate code]
137 *
138 * TODO: more testing for optimal parameters.
139 *       multi-channel tests at 44.1kHz and 32kHz.
140 */
141static const int8_t ac3_coupling_start_tab[6][3][19] = {
142//      32  40  48  56  64  80  96 112 128 160 192 224 256 320 384 448 512 576 640
143
144    // 2/0
145    { {  0,  0,  0,  0,  0,  0,  0,  1,  1,  7,  8, 11, 12, -1, -1, -1, -1, -1, -1 },
146      {  0,  0,  0,  0,  0,  0,  1,  3,  5,  7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
147      {  0,  0,  0,  0,  1,  2,  2,  9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
148
149    // 3/0
150    { {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
151      {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
152      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
153
154    // 2/1 - untested
155    { {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
156      {  0,  0,  0,  0,  0,  0,  0,  0,  2,  2,  6,  9, 11, 12, 13, -1, -1, -1, -1 },
157      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
158
159    // 3/1
160    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
161      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
162      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
163
164    // 2/2 - untested
165    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
166      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  3,  2, 10, 11, 11, 12, 12, 14, -1 },
167      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
168
169    // 3/2
170    { {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  6,  8, 11, 12, 12, -1, -1 },
171      {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  6,  8, 11, 12, 12, -1, -1 },
172      { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
173};
174
175
176/**
177 * Adjust the frame size to make the average bit rate match the target bit rate.
178 * This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3.
179 *
180 * @param s  AC-3 encoder private context
181 */
182void ff_ac3_adjust_frame_size(AC3EncodeContext *s)
183{
184    while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
185        s->bits_written    -= s->bit_rate;
186        s->samples_written -= s->sample_rate;
187    }
188    s->frame_size = s->frame_size_min +
189                    2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
190    s->bits_written    += s->frame_size * 8;
191    s->samples_written += AC3_BLOCK_SIZE * s->num_blocks;
192}
193
194
195/**
196 * Set the initial coupling strategy parameters prior to coupling analysis.
197 *
198 * @param s  AC-3 encoder private context
199 */
200void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
201{
202    int blk, ch;
203    int got_cpl_snr;
204    int num_cpl_blocks;
205
206    /* set coupling use flags for each block/channel */
207    /* TODO: turn coupling on/off and adjust start band based on bit usage */
208    for (blk = 0; blk < s->num_blocks; blk++) {
209        AC3Block *block = &s->blocks[blk];
210        for (ch = 1; ch <= s->fbw_channels; ch++)
211            block->channel_in_cpl[ch] = s->cpl_on;
212    }
213
214    /* enable coupling for each block if at least 2 channels have coupling
215       enabled for that block */
216    got_cpl_snr = 0;
217    num_cpl_blocks = 0;
218    for (blk = 0; blk < s->num_blocks; blk++) {
219        AC3Block *block = &s->blocks[blk];
220        block->num_cpl_channels = 0;
221        for (ch = 1; ch <= s->fbw_channels; ch++)
222            block->num_cpl_channels += block->channel_in_cpl[ch];
223        block->cpl_in_use = block->num_cpl_channels > 1;
224        num_cpl_blocks += block->cpl_in_use;
225        if (!block->cpl_in_use) {
226            block->num_cpl_channels = 0;
227            for (ch = 1; ch <= s->fbw_channels; ch++)
228                block->channel_in_cpl[ch] = 0;
229        }
230
231        block->new_cpl_strategy = !blk;
232        if (blk) {
233            for (ch = 1; ch <= s->fbw_channels; ch++) {
234                if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
235                    block->new_cpl_strategy = 1;
236                    break;
237                }
238            }
239        }
240        block->new_cpl_leak = block->new_cpl_strategy;
241
242        if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
243            block->new_snr_offsets = 1;
244            if (block->cpl_in_use)
245                got_cpl_snr = 1;
246        } else {
247            block->new_snr_offsets = 0;
248        }
249    }
250    if (!num_cpl_blocks)
251        s->cpl_on = 0;
252
253    /* set bandwidth for each channel */
254    for (blk = 0; blk < s->num_blocks; blk++) {
255        AC3Block *block = &s->blocks[blk];
256        for (ch = 1; ch <= s->fbw_channels; ch++) {
257            if (block->channel_in_cpl[ch])
258                block->end_freq[ch] = s->start_freq[CPL_CH];
259            else
260                block->end_freq[ch] = s->bandwidth_code * 3 + 73;
261        }
262    }
263}
264
265
266/**
267 * Apply stereo rematrixing to coefficients based on rematrixing flags.
268 *
269 * @param s  AC-3 encoder private context
270 */
271void ff_ac3_apply_rematrixing(AC3EncodeContext *s)
272{
273    int nb_coefs;
274    int blk, bnd, i;
275    int start, end;
276    uint8_t *flags;
277
278    if (!s->rematrixing_enabled)
279        return;
280
281    for (blk = 0; blk < s->num_blocks; blk++) {
282        AC3Block *block = &s->blocks[blk];
283        if (block->new_rematrixing_strategy)
284            flags = block->rematrixing_flags;
285        nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
286        for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
287            if (flags[bnd]) {
288                start = ff_ac3_rematrix_band_tab[bnd];
289                end   = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
290                for (i = start; i < end; i++) {
291                    int32_t lt = block->fixed_coef[1][i];
292                    int32_t rt = block->fixed_coef[2][i];
293                    block->fixed_coef[1][i] = (lt + rt) >> 1;
294                    block->fixed_coef[2][i] = (lt - rt) >> 1;
295                }
296            }
297        }
298    }
299}
300
301
302/*
303 * Initialize exponent tables.
304 */
305static av_cold void exponent_init(AC3EncodeContext *s)
306{
307    int expstr, i, grpsize;
308
309    for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
310        grpsize = 3 << expstr;
311        for (i = 12; i < 256; i++) {
312            exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
313            exponent_group_tab[1][expstr][i] = (i              ) / grpsize;
314        }
315    }
316    /* LFE */
317    exponent_group_tab[0][0][7] = 2;
318
319    if (CONFIG_EAC3_ENCODER && s->eac3)
320        ff_eac3_exponent_init();
321}
322
323
324/*
325 * Extract exponents from the MDCT coefficients.
326 */
327static void extract_exponents(AC3EncodeContext *s)
328{
329    int ch        = !s->cpl_on;
330    int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
331    AC3Block *block = &s->blocks[0];
332
333    s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
334}
335
336
337/**
338 * Exponent Difference Threshold.
339 * New exponents are sent if their SAD exceed this number.
340 */
341#define EXP_DIFF_THRESHOLD 500
342
343/**
344 * Table used to select exponent strategy based on exponent reuse block interval.
345 */
346static const uint8_t exp_strategy_reuse_tab[4][6] = {
347    { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
348    { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
349    { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
350    { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 }
351};
352
353/*
354 * Calculate exponent strategies for all channels.
355 * Array arrangement is reversed to simplify the per-channel calculation.
356 */
357static void compute_exp_strategy(AC3EncodeContext *s)
358{
359    int ch, blk, blk1;
360
361    for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
362        uint8_t *exp_strategy = s->exp_strategy[ch];
363        uint8_t *exp          = s->blocks[0].exp[ch];
364        int exp_diff;
365
366        /* estimate if the exponent variation & decide if they should be
367           reused in the next frame */
368        exp_strategy[0] = EXP_NEW;
369        exp += AC3_MAX_COEFS;
370        for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
371            if (ch == CPL_CH) {
372                if (!s->blocks[blk-1].cpl_in_use) {
373                    exp_strategy[blk] = EXP_NEW;
374                    continue;
375                } else if (!s->blocks[blk].cpl_in_use) {
376                    exp_strategy[blk] = EXP_REUSE;
377                    continue;
378                }
379            } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
380                exp_strategy[blk] = EXP_NEW;
381                continue;
382            }
383            exp_diff = s->dsp.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
384            exp_strategy[blk] = EXP_REUSE;
385            if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
386                exp_strategy[blk] = EXP_NEW;
387            else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
388                exp_strategy[blk] = EXP_NEW;
389        }
390
391        /* now select the encoding strategy type : if exponents are often
392           recoded, we use a coarse encoding */
393        blk = 0;
394        while (blk < s->num_blocks) {
395            blk1 = blk + 1;
396            while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
397                blk1++;
398            exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
399            blk = blk1;
400        }
401    }
402    if (s->lfe_on) {
403        ch = s->lfe_channel;
404        s->exp_strategy[ch][0] = EXP_D15;
405        for (blk = 1; blk < s->num_blocks; blk++)
406            s->exp_strategy[ch][blk] = EXP_REUSE;
407    }
408
409    /* for E-AC-3, determine frame exponent strategy */
410    if (CONFIG_EAC3_ENCODER && s->eac3)
411        ff_eac3_get_frame_exp_strategy(s);
412}
413
414
415/**
416 * Update the exponents so that they are the ones the decoder will decode.
417 *
418 * @param[in,out] exp   array of exponents for 1 block in 1 channel
419 * @param nb_exps       number of exponents in active bandwidth
420 * @param exp_strategy  exponent strategy for the block
421 * @param cpl           indicates if the block is in the coupling channel
422 */
423static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
424                                    int cpl)
425{
426    int nb_groups, i, k;
427
428    nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
429
430    /* for each group, compute the minimum exponent */
431    switch(exp_strategy) {
432    case EXP_D25:
433        for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
434            uint8_t exp_min = exp[k];
435            if (exp[k+1] < exp_min)
436                exp_min = exp[k+1];
437            exp[i-cpl] = exp_min;
438            k += 2;
439        }
440        break;
441    case EXP_D45:
442        for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
443            uint8_t exp_min = exp[k];
444            if (exp[k+1] < exp_min)
445                exp_min = exp[k+1];
446            if (exp[k+2] < exp_min)
447                exp_min = exp[k+2];
448            if (exp[k+3] < exp_min)
449                exp_min = exp[k+3];
450            exp[i-cpl] = exp_min;
451            k += 4;
452        }
453        break;
454    }
455
456    /* constraint for DC exponent */
457    if (!cpl && exp[0] > 15)
458        exp[0] = 15;
459
460    /* decrease the delta between each groups to within 2 so that they can be
461       differentially encoded */
462    for (i = 1; i <= nb_groups; i++)
463        exp[i] = FFMIN(exp[i], exp[i-1] + 2);
464    i--;
465    while (--i >= 0)
466        exp[i] = FFMIN(exp[i], exp[i+1] + 2);
467
468    if (cpl)
469        exp[-1] = exp[0] & ~1;
470
471    /* now we have the exponent values the decoder will see */
472    switch (exp_strategy) {
473    case EXP_D25:
474        for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
475            uint8_t exp1 = exp[i-cpl];
476            exp[k--] = exp1;
477            exp[k--] = exp1;
478        }
479        break;
480    case EXP_D45:
481        for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
482            exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
483            k -= 4;
484        }
485        break;
486    }
487}
488
489
490/*
491 * Encode exponents from original extracted form to what the decoder will see.
492 * This copies and groups exponents based on exponent strategy and reduces
493 * deltas between adjacent exponent groups so that they can be differentially
494 * encoded.
495 */
496static void encode_exponents(AC3EncodeContext *s)
497{
498    int blk, blk1, ch, cpl;
499    uint8_t *exp, *exp_strategy;
500    int nb_coefs, num_reuse_blocks;
501
502    for (ch = !s->cpl_on; ch <= s->channels; ch++) {
503        exp          = s->blocks[0].exp[ch] + s->start_freq[ch];
504        exp_strategy = s->exp_strategy[ch];
505
506        cpl = (ch == CPL_CH);
507        blk = 0;
508        while (blk < s->num_blocks) {
509            AC3Block *block = &s->blocks[blk];
510            if (cpl && !block->cpl_in_use) {
511                exp += AC3_MAX_COEFS;
512                blk++;
513                continue;
514            }
515            nb_coefs = block->end_freq[ch] - s->start_freq[ch];
516            blk1 = blk + 1;
517
518            /* count the number of EXP_REUSE blocks after the current block
519               and set exponent reference block numbers */
520            s->exp_ref_block[ch][blk] = blk;
521            while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
522                s->exp_ref_block[ch][blk1] = blk;
523                blk1++;
524            }
525            num_reuse_blocks = blk1 - blk - 1;
526
527            /* for the EXP_REUSE case we select the min of the exponents */
528            s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
529                                       AC3_MAX_COEFS);
530
531            encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
532
533            exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
534            blk = blk1;
535        }
536    }
537
538    /* reference block numbers have been changed, so reset ref_bap_set */
539    s->ref_bap_set = 0;
540}
541
542
543/*
544 * Count exponent bits based on bandwidth, coupling, and exponent strategies.
545 */
546static int count_exponent_bits(AC3EncodeContext *s)
547{
548    int blk, ch;
549    int nb_groups, bit_count;
550
551    bit_count = 0;
552    for (blk = 0; blk < s->num_blocks; blk++) {
553        AC3Block *block = &s->blocks[blk];
554        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
555            int exp_strategy = s->exp_strategy[ch][blk];
556            int cpl          = (ch == CPL_CH);
557            int nb_coefs     = block->end_freq[ch] - s->start_freq[ch];
558
559            if (exp_strategy == EXP_REUSE)
560                continue;
561
562            nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
563            bit_count += 4 + (nb_groups * 7);
564        }
565    }
566
567    return bit_count;
568}
569
570
571/**
572 * Group exponents.
573 * 3 delta-encoded exponents are in each 7-bit group. The number of groups
574 * varies depending on exponent strategy and bandwidth.
575 *
576 * @param s  AC-3 encoder private context
577 */
578void ff_ac3_group_exponents(AC3EncodeContext *s)
579{
580    int blk, ch, i, cpl;
581    int group_size, nb_groups;
582    uint8_t *p;
583    int delta0, delta1, delta2;
584    int exp0, exp1;
585
586    for (blk = 0; blk < s->num_blocks; blk++) {
587        AC3Block *block = &s->blocks[blk];
588        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
589            int exp_strategy = s->exp_strategy[ch][blk];
590            if (exp_strategy == EXP_REUSE)
591                continue;
592            cpl = (ch == CPL_CH);
593            group_size = exp_strategy + (exp_strategy == EXP_D45);
594            nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
595            p = block->exp[ch] + s->start_freq[ch] - cpl;
596
597            /* DC exponent */
598            exp1 = *p++;
599            block->grouped_exp[ch][0] = exp1;
600
601            /* remaining exponents are delta encoded */
602            for (i = 1; i <= nb_groups; i++) {
603                /* merge three delta in one code */
604                exp0   = exp1;
605                exp1   = p[0];
606                p     += group_size;
607                delta0 = exp1 - exp0 + 2;
608                av_assert2(delta0 >= 0 && delta0 <= 4);
609
610                exp0   = exp1;
611                exp1   = p[0];
612                p     += group_size;
613                delta1 = exp1 - exp0 + 2;
614                av_assert2(delta1 >= 0 && delta1 <= 4);
615
616                exp0   = exp1;
617                exp1   = p[0];
618                p     += group_size;
619                delta2 = exp1 - exp0 + 2;
620                av_assert2(delta2 >= 0 && delta2 <= 4);
621
622                block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
623            }
624        }
625    }
626}
627
628
629/**
630 * Calculate final exponents from the supplied MDCT coefficients and exponent shift.
631 * Extract exponents from MDCT coefficients, calculate exponent strategies,
632 * and encode final exponents.
633 *
634 * @param s  AC-3 encoder private context
635 */
636void ff_ac3_process_exponents(AC3EncodeContext *s)
637{
638    extract_exponents(s);
639
640    compute_exp_strategy(s);
641
642    encode_exponents(s);
643
644    emms_c();
645}
646
647
648/*
649 * Count frame bits that are based solely on fixed parameters.
650 * This only has to be run once when the encoder is initialized.
651 */
652static void count_frame_bits_fixed(AC3EncodeContext *s)
653{
654    static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
655    int blk;
656    int frame_bits;
657
658    /* assumptions:
659     *   no dynamic range codes
660     *   bit allocation parameters do not change between blocks
661     *   no delta bit allocation
662     *   no skipped data
663     *   no auxilliary data
664     *   no E-AC-3 metadata
665     */
666
667    /* header */
668    frame_bits = 16; /* sync info */
669    if (s->eac3) {
670        /* bitstream info header */
671        frame_bits += 35;
672        frame_bits += 1 + 1;
673        if (s->num_blocks != 0x6)
674            frame_bits++;
675        frame_bits++;
676        /* audio frame header */
677        if (s->num_blocks == 6)
678            frame_bits += 2;
679        frame_bits += 10;
680        /* exponent strategy */
681        if (s->use_frame_exp_strategy)
682            frame_bits += 5 * s->fbw_channels;
683        else
684            frame_bits += s->num_blocks * 2 * s->fbw_channels;
685        if (s->lfe_on)
686            frame_bits += s->num_blocks;
687        /* converter exponent strategy */
688        if (s->num_blks_code != 0x3)
689            frame_bits++;
690        else
691            frame_bits += s->fbw_channels * 5;
692        /* snr offsets */
693        frame_bits += 10;
694        /* block start info */
695        if (s->num_blocks != 1)
696            frame_bits++;
697    } else {
698        frame_bits += 49;
699        frame_bits += frame_bits_inc[s->channel_mode];
700    }
701
702    /* audio blocks */
703    for (blk = 0; blk < s->num_blocks; blk++) {
704        if (!s->eac3) {
705            /* block switch flags */
706            frame_bits += s->fbw_channels;
707
708            /* dither flags */
709            frame_bits += s->fbw_channels;
710        }
711
712        /* dynamic range */
713        frame_bits++;
714
715        /* spectral extension */
716        if (s->eac3)
717            frame_bits++;
718
719        if (!s->eac3) {
720            /* exponent strategy */
721            frame_bits += 2 * s->fbw_channels;
722            if (s->lfe_on)
723                frame_bits++;
724
725            /* bit allocation params */
726            frame_bits++;
727            if (!blk)
728                frame_bits += 2 + 2 + 2 + 2 + 3;
729        }
730
731        /* converter snr offset */
732        if (s->eac3)
733            frame_bits++;
734
735        if (!s->eac3) {
736            /* delta bit allocation */
737            frame_bits++;
738
739            /* skipped data */
740            frame_bits++;
741        }
742    }
743
744    /* auxiliary data */
745    frame_bits++;
746
747    /* CRC */
748    frame_bits += 1 + 16;
749
750    s->frame_bits_fixed = frame_bits;
751}
752
753
754/*
755 * Initialize bit allocation.
756 * Set default parameter codes and calculate parameter values.
757 */
758static void bit_alloc_init(AC3EncodeContext *s)
759{
760    int ch;
761
762    /* init default parameters */
763    s->slow_decay_code = 2;
764    s->fast_decay_code = 1;
765    s->slow_gain_code  = 1;
766    s->db_per_bit_code = s->eac3 ? 2 : 3;
767    s->floor_code      = 7;
768    for (ch = 0; ch <= s->channels; ch++)
769        s->fast_gain_code[ch] = 4;
770
771    /* initial snr offset */
772    s->coarse_snr_offset = 40;
773
774    /* compute real values */
775    /* currently none of these values change during encoding, so we can just
776       set them once at initialization */
777    s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift;
778    s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift;
779    s->bit_alloc.slow_gain  = ff_ac3_slow_gain_tab[s->slow_gain_code];
780    s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
781    s->bit_alloc.floor      = ff_ac3_floor_tab[s->floor_code];
782    s->bit_alloc.cpl_fast_leak = 0;
783    s->bit_alloc.cpl_slow_leak = 0;
784
785    count_frame_bits_fixed(s);
786}
787
788
789/*
790 * Count the bits used to encode the frame, minus exponents and mantissas.
791 * Bits based on fixed parameters have already been counted, so now we just
792 * have to add the bits based on parameters that change during encoding.
793 */
794static void count_frame_bits(AC3EncodeContext *s)
795{
796    AC3EncOptions *opt = &s->options;
797    int blk, ch;
798    int frame_bits = 0;
799
800    /* header */
801    if (s->eac3) {
802        if (opt->eac3_mixing_metadata) {
803            if (s->channel_mode > AC3_CHMODE_STEREO)
804                frame_bits += 2;
805            if (s->has_center)
806                frame_bits += 6;
807            if (s->has_surround)
808                frame_bits += 6;
809            frame_bits += s->lfe_on;
810            frame_bits += 1 + 1 + 2;
811            if (s->channel_mode < AC3_CHMODE_STEREO)
812                frame_bits++;
813            frame_bits++;
814        }
815        if (opt->eac3_info_metadata) {
816            frame_bits += 3 + 1 + 1;
817            if (s->channel_mode == AC3_CHMODE_STEREO)
818                frame_bits += 2 + 2;
819            if (s->channel_mode >= AC3_CHMODE_2F2R)
820                frame_bits += 2;
821            frame_bits++;
822            if (opt->audio_production_info)
823                frame_bits += 5 + 2 + 1;
824            frame_bits++;
825        }
826        /* coupling */
827        if (s->channel_mode > AC3_CHMODE_MONO) {
828            frame_bits++;
829            for (blk = 1; blk < s->num_blocks; blk++) {
830                AC3Block *block = &s->blocks[blk];
831                frame_bits++;
832                if (block->new_cpl_strategy)
833                    frame_bits++;
834            }
835        }
836        /* coupling exponent strategy */
837        if (s->cpl_on) {
838            if (s->use_frame_exp_strategy) {
839                frame_bits += 5 * s->cpl_on;
840            } else {
841                for (blk = 0; blk < s->num_blocks; blk++)
842                    frame_bits += 2 * s->blocks[blk].cpl_in_use;
843            }
844        }
845    } else {
846        if (opt->audio_production_info)
847            frame_bits += 7;
848        if (s->bitstream_id == 6) {
849            if (opt->extended_bsi_1)
850                frame_bits += 14;
851            if (opt->extended_bsi_2)
852                frame_bits += 14;
853        }
854    }
855
856    /* audio blocks */
857    for (blk = 0; blk < s->num_blocks; blk++) {
858        AC3Block *block = &s->blocks[blk];
859
860        /* coupling strategy */
861        if (!s->eac3)
862            frame_bits++;
863        if (block->new_cpl_strategy) {
864            if (!s->eac3)
865                frame_bits++;
866            if (block->cpl_in_use) {
867                if (s->eac3)
868                    frame_bits++;
869                if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
870                    frame_bits += s->fbw_channels;
871                if (s->channel_mode == AC3_CHMODE_STEREO)
872                    frame_bits++;
873                frame_bits += 4 + 4;
874                if (s->eac3)
875                    frame_bits++;
876                else
877                    frame_bits += s->num_cpl_subbands - 1;
878            }
879        }
880
881        /* coupling coordinates */
882        if (block->cpl_in_use) {
883            for (ch = 1; ch <= s->fbw_channels; ch++) {
884                if (block->channel_in_cpl[ch]) {
885                    if (!s->eac3 || block->new_cpl_coords[ch] != 2)
886                        frame_bits++;
887                    if (block->new_cpl_coords[ch]) {
888                        frame_bits += 2;
889                        frame_bits += (4 + 4) * s->num_cpl_bands;
890                    }
891                }
892            }
893        }
894
895        /* stereo rematrixing */
896        if (s->channel_mode == AC3_CHMODE_STEREO) {
897            if (!s->eac3 || blk > 0)
898                frame_bits++;
899            if (s->blocks[blk].new_rematrixing_strategy)
900                frame_bits += block->num_rematrixing_bands;
901        }
902
903        /* bandwidth codes & gain range */
904        for (ch = 1; ch <= s->fbw_channels; ch++) {
905            if (s->exp_strategy[ch][blk] != EXP_REUSE) {
906                if (!block->channel_in_cpl[ch])
907                    frame_bits += 6;
908                frame_bits += 2;
909            }
910        }
911
912        /* coupling exponent strategy */
913        if (!s->eac3 && block->cpl_in_use)
914            frame_bits += 2;
915
916        /* snr offsets and fast gain codes */
917        if (!s->eac3) {
918            frame_bits++;
919            if (block->new_snr_offsets)
920                frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
921        }
922
923        /* coupling leak info */
924        if (block->cpl_in_use) {
925            if (!s->eac3 || block->new_cpl_leak != 2)
926                frame_bits++;
927            if (block->new_cpl_leak)
928                frame_bits += 3 + 3;
929        }
930    }
931
932    s->frame_bits = s->frame_bits_fixed + frame_bits;
933}
934
935
936/*
937 * Calculate masking curve based on the final exponents.
938 * Also calculate the power spectral densities to use in future calculations.
939 */
940static void bit_alloc_masking(AC3EncodeContext *s)
941{
942    int blk, ch;
943
944    for (blk = 0; blk < s->num_blocks; blk++) {
945        AC3Block *block = &s->blocks[blk];
946        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
947            /* We only need psd and mask for calculating bap.
948               Since we currently do not calculate bap when exponent
949               strategy is EXP_REUSE we do not need to calculate psd or mask. */
950            if (s->exp_strategy[ch][blk] != EXP_REUSE) {
951                ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
952                                          block->end_freq[ch], block->psd[ch],
953                                          block->band_psd[ch]);
954                ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch],
955                                           s->start_freq[ch], block->end_freq[ch],
956                                           ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],
957                                           ch == s->lfe_channel,
958                                           DBA_NONE, 0, NULL, NULL, NULL,
959                                           block->mask[ch]);
960            }
961        }
962    }
963}
964
965
966/*
967 * Ensure that bap for each block and channel point to the current bap_buffer.
968 * They may have been switched during the bit allocation search.
969 */
970static void reset_block_bap(AC3EncodeContext *s)
971{
972    int blk, ch;
973    uint8_t *ref_bap;
974
975    if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
976        return;
977
978    ref_bap = s->bap_buffer;
979    for (ch = 0; ch <= s->channels; ch++) {
980        for (blk = 0; blk < s->num_blocks; blk++)
981            s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
982        ref_bap += AC3_MAX_COEFS * s->num_blocks;
983    }
984    s->ref_bap_set = 1;
985}
986
987
988/**
989 * Initialize mantissa counts.
990 * These are set so that they are padded to the next whole group size when bits
991 * are counted in compute_mantissa_size.
992 *
993 * @param[in,out] mant_cnt  running counts for each bap value for each block
994 */
995static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
996{
997    int blk;
998
999    for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
1000        memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
1001        mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
1002        mant_cnt[blk][4] = 1;
1003    }
1004}
1005
1006
1007/**
1008 * Update mantissa bit counts for all blocks in 1 channel in a given bandwidth
1009 * range.
1010 *
1011 * @param s                 AC-3 encoder private context
1012 * @param ch                channel index
1013 * @param[in,out] mant_cnt  running counts for each bap value for each block
1014 * @param start             starting coefficient bin
1015 * @param end               ending coefficient bin
1016 */
1017static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch,
1018                                          uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
1019                                          int start, int end)
1020{
1021    int blk;
1022
1023    for (blk = 0; blk < s->num_blocks; blk++) {
1024        AC3Block *block = &s->blocks[blk];
1025        if (ch == CPL_CH && !block->cpl_in_use)
1026            continue;
1027        s->ac3dsp.update_bap_counts(mant_cnt[blk],
1028                                    s->ref_bap[ch][blk] + start,
1029                                    FFMIN(end, block->end_freq[ch]) - start);
1030    }
1031}
1032
1033
1034/*
1035 * Count the number of mantissa bits in the frame based on the bap values.
1036 */
1037static int count_mantissa_bits(AC3EncodeContext *s)
1038{
1039    int ch, max_end_freq;
1040    LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
1041
1042    count_mantissa_bits_init(mant_cnt);
1043
1044    max_end_freq = s->bandwidth_code * 3 + 73;
1045    for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
1046        count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
1047                                      max_end_freq);
1048
1049    return s->ac3dsp.compute_mantissa_size(mant_cnt);
1050}
1051
1052
1053/**
1054 * Run the bit allocation with a given SNR offset.
1055 * This calculates the bit allocation pointers that will be used to determine
1056 * the quantization of each mantissa.
1057 *
1058 * @param s           AC-3 encoder private context
1059 * @param snr_offset  SNR offset, 0 to 1023
1060 * @return the number of bits needed for mantissas if the given SNR offset is
1061 *         is used.
1062 */
1063static int bit_alloc(AC3EncodeContext *s, int snr_offset)
1064{
1065    int blk, ch;
1066
1067    snr_offset = (snr_offset - 240) << 2;
1068
1069    reset_block_bap(s);
1070    for (blk = 0; blk < s->num_blocks; blk++) {
1071        AC3Block *block = &s->blocks[blk];
1072
1073        for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1074            /* Currently the only bit allocation parameters which vary across
1075               blocks within a frame are the exponent values.  We can take
1076               advantage of that by reusing the bit allocation pointers
1077               whenever we reuse exponents. */
1078            if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1079                s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
1080                                             s->start_freq[ch], block->end_freq[ch],
1081                                             snr_offset, s->bit_alloc.floor,
1082                                             ff_ac3_bap_tab, s->ref_bap[ch][blk]);
1083            }
1084        }
1085    }
1086    return count_mantissa_bits(s);
1087}
1088
1089
1090/*
1091 * Constant bitrate bit allocation search.
1092 * Find the largest SNR offset that will allow data to fit in the frame.
1093 */
1094static int cbr_bit_allocation(AC3EncodeContext *s)
1095{
1096    int ch;
1097    int bits_left;
1098    int snr_offset, snr_incr;
1099
1100    bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
1101    if (bits_left < 0)
1102        return AVERROR(EINVAL);
1103
1104    snr_offset = s->coarse_snr_offset << 4;
1105
1106    /* if previous frame SNR offset was 1023, check if current frame can also
1107       use SNR offset of 1023. if so, skip the search. */
1108    if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
1109        if (bit_alloc(s, 1023) <= bits_left)
1110            return 0;
1111    }
1112
1113    while (snr_offset >= 0 &&
1114           bit_alloc(s, snr_offset) > bits_left) {
1115        snr_offset -= 64;
1116    }
1117    if (snr_offset < 0)
1118        return AVERROR(EINVAL);
1119
1120    FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1121    for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
1122        while (snr_offset + snr_incr <= 1023 &&
1123               bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
1124            snr_offset += snr_incr;
1125            FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1126        }
1127    }
1128    FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1129    reset_block_bap(s);
1130
1131    s->coarse_snr_offset = snr_offset >> 4;
1132    for (ch = !s->cpl_on; ch <= s->channels; ch++)
1133        s->fine_snr_offset[ch] = snr_offset & 0xF;
1134
1135    return 0;
1136}
1137
1138
1139/*
1140 * Perform bit allocation search.
1141 * Finds the SNR offset value that maximizes quality and fits in the specified
1142 * frame size.  Output is the SNR offset and a set of bit allocation pointers
1143 * used to quantize the mantissas.
1144 */
1145int ff_ac3_compute_bit_allocation(AC3EncodeContext *s)
1146{
1147    count_frame_bits(s);
1148
1149    s->exponent_bits = count_exponent_bits(s);
1150
1151    bit_alloc_masking(s);
1152
1153    return cbr_bit_allocation(s);
1154}
1155
1156
1157/**
1158 * Symmetric quantization on 'levels' levels.
1159 *
1160 * @param c       unquantized coefficient
1161 * @param e       exponent
1162 * @param levels  number of quantization levels
1163 * @return        quantized coefficient
1164 */
1165static inline int sym_quant(int c, int e, int levels)
1166{
1167    int v = (((levels * c) >> (24 - e)) + levels) >> 1;
1168    av_assert2(v >= 0 && v < levels);
1169    return v;
1170}
1171
1172
1173/**
1174 * Asymmetric quantization on 2^qbits levels.
1175 *
1176 * @param c      unquantized coefficient
1177 * @param e      exponent
1178 * @param qbits  number of quantization bits
1179 * @return       quantized coefficient
1180 */
1181static inline int asym_quant(int c, int e, int qbits)
1182{
1183    int m;
1184
1185    c = (((c << e) >> (24 - qbits)) + 1) >> 1;
1186    m = (1 << (qbits-1));
1187    if (c >= m)
1188        c = m - 1;
1189    av_assert2(c >= -m);
1190    return c;
1191}
1192
1193
1194/**
1195 * Quantize a set of mantissas for a single channel in a single block.
1196 *
1197 * @param s           Mantissa count context
1198 * @param fixed_coef  unquantized fixed-point coefficients
1199 * @param exp         exponents
1200 * @param bap         bit allocation pointer indices
1201 * @param[out] qmant  quantized coefficients
1202 * @param start_freq  starting coefficient bin
1203 * @param end_freq    ending coefficient bin
1204 */
1205static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
1206                                      uint8_t *exp, uint8_t *bap,
1207                                      int16_t *qmant, int start_freq,
1208                                      int end_freq)
1209{
1210    int i;
1211
1212    for (i = start_freq; i < end_freq; i++) {
1213        int v;
1214        int c = fixed_coef[i];
1215        int e = exp[i];
1216        int b = bap[i];
1217        switch (b) {
1218        case 0:
1219            v = 0;
1220            break;
1221        case 1:
1222            v = sym_quant(c, e, 3);
1223            switch (s->mant1_cnt) {
1224            case 0:
1225                s->qmant1_ptr = &qmant[i];
1226                v = 9 * v;
1227                s->mant1_cnt = 1;
1228                break;
1229            case 1:
1230                *s->qmant1_ptr += 3 * v;
1231                s->mant1_cnt = 2;
1232                v = 128;
1233                break;
1234            default:
1235                *s->qmant1_ptr += v;
1236                s->mant1_cnt = 0;
1237                v = 128;
1238                break;
1239            }
1240            break;
1241        case 2:
1242            v = sym_quant(c, e, 5);
1243            switch (s->mant2_cnt) {
1244            case 0:
1245                s->qmant2_ptr = &qmant[i];
1246                v = 25 * v;
1247                s->mant2_cnt = 1;
1248                break;
1249            case 1:
1250                *s->qmant2_ptr += 5 * v;
1251                s->mant2_cnt = 2;
1252                v = 128;
1253                break;
1254            default:
1255                *s->qmant2_ptr += v;
1256                s->mant2_cnt = 0;
1257                v = 128;
1258                break;
1259            }
1260            break;
1261        case 3:
1262            v = sym_quant(c, e, 7);
1263            break;
1264        case 4:
1265            v = sym_quant(c, e, 11);
1266            switch (s->mant4_cnt) {
1267            case 0:
1268                s->qmant4_ptr = &qmant[i];
1269                v = 11 * v;
1270                s->mant4_cnt = 1;
1271                break;
1272            default:
1273                *s->qmant4_ptr += v;
1274                s->mant4_cnt = 0;
1275                v = 128;
1276                break;
1277            }
1278            break;
1279        case 5:
1280            v = sym_quant(c, e, 15);
1281            break;
1282        case 14:
1283            v = asym_quant(c, e, 14);
1284            break;
1285        case 15:
1286            v = asym_quant(c, e, 16);
1287            break;
1288        default:
1289            v = asym_quant(c, e, b - 1);
1290            break;
1291        }
1292        qmant[i] = v;
1293    }
1294}
1295
1296
1297/**
1298 * Quantize mantissas using coefficients, exponents, and bit allocation pointers.
1299 *
1300 * @param s  AC-3 encoder private context
1301 */
1302void ff_ac3_quantize_mantissas(AC3EncodeContext *s)
1303{
1304    int blk, ch, ch0=0, got_cpl;
1305
1306    for (blk = 0; blk < s->num_blocks; blk++) {
1307        AC3Block *block = &s->blocks[blk];
1308        AC3Mant m = { 0 };
1309
1310        got_cpl = !block->cpl_in_use;
1311        for (ch = 1; ch <= s->channels; ch++) {
1312            if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1313                ch0     = ch - 1;
1314                ch      = CPL_CH;
1315                got_cpl = 1;
1316            }
1317            quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
1318                                      s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
1319                                      s->ref_bap[ch][blk], block->qmant[ch],
1320                                      s->start_freq[ch], block->end_freq[ch]);
1321            if (ch == CPL_CH)
1322                ch = ch0;
1323        }
1324    }
1325}
1326
1327
1328/*
1329 * Write the AC-3 frame header to the output bitstream.
1330 */
1331static void ac3_output_frame_header(AC3EncodeContext *s)
1332{
1333    AC3EncOptions *opt = &s->options;
1334
1335    put_bits(&s->pb, 16, 0x0b77);   /* frame header */
1336    put_bits(&s->pb, 16, 0);        /* crc1: will be filled later */
1337    put_bits(&s->pb, 2,  s->bit_alloc.sr_code);
1338    put_bits(&s->pb, 6,  s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
1339    put_bits(&s->pb, 5,  s->bitstream_id);
1340    put_bits(&s->pb, 3,  s->bitstream_mode);
1341    put_bits(&s->pb, 3,  s->channel_mode);
1342    if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
1343        put_bits(&s->pb, 2, s->center_mix_level);
1344    if (s->channel_mode & 0x04)
1345        put_bits(&s->pb, 2, s->surround_mix_level);
1346    if (s->channel_mode == AC3_CHMODE_STEREO)
1347        put_bits(&s->pb, 2, opt->dolby_surround_mode);
1348    put_bits(&s->pb, 1, s->lfe_on); /* LFE */
1349    put_bits(&s->pb, 5, -opt->dialogue_level);
1350    put_bits(&s->pb, 1, 0);         /* no compression control word */
1351    put_bits(&s->pb, 1, 0);         /* no lang code */
1352    put_bits(&s->pb, 1, opt->audio_production_info);
1353    if (opt->audio_production_info) {
1354        put_bits(&s->pb, 5, opt->mixing_level - 80);
1355        put_bits(&s->pb, 2, opt->room_type);
1356    }
1357    put_bits(&s->pb, 1, opt->copyright);
1358    put_bits(&s->pb, 1, opt->original);
1359    if (s->bitstream_id == 6) {
1360        /* alternate bit stream syntax */
1361        put_bits(&s->pb, 1, opt->extended_bsi_1);
1362        if (opt->extended_bsi_1) {
1363            put_bits(&s->pb, 2, opt->preferred_stereo_downmix);
1364            put_bits(&s->pb, 3, s->ltrt_center_mix_level);
1365            put_bits(&s->pb, 3, s->ltrt_surround_mix_level);
1366            put_bits(&s->pb, 3, s->loro_center_mix_level);
1367            put_bits(&s->pb, 3, s->loro_surround_mix_level);
1368        }
1369        put_bits(&s->pb, 1, opt->extended_bsi_2);
1370        if (opt->extended_bsi_2) {
1371            put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);
1372            put_bits(&s->pb, 2, opt->dolby_headphone_mode);
1373            put_bits(&s->pb, 1, opt->ad_converter_type);
1374            put_bits(&s->pb, 9, 0);     /* xbsi2 and encinfo : reserved */
1375        }
1376    } else {
1377    put_bits(&s->pb, 1, 0);         /* no time code 1 */
1378    put_bits(&s->pb, 1, 0);         /* no time code 2 */
1379    }
1380    put_bits(&s->pb, 1, 0);         /* no additional bit stream info */
1381}
1382
1383
1384/*
1385 * Write one audio block to the output bitstream.
1386 */
1387static void output_audio_block(AC3EncodeContext *s, int blk)
1388{
1389    int ch, i, baie, bnd, got_cpl;
1390    int av_uninit(ch0);
1391    AC3Block *block = &s->blocks[blk];
1392
1393    /* block switching */
1394    if (!s->eac3) {
1395        for (ch = 0; ch < s->fbw_channels; ch++)
1396            put_bits(&s->pb, 1, 0);
1397    }
1398
1399    /* dither flags */
1400    if (!s->eac3) {
1401        for (ch = 0; ch < s->fbw_channels; ch++)
1402            put_bits(&s->pb, 1, 1);
1403    }
1404
1405    /* dynamic range codes */
1406    put_bits(&s->pb, 1, 0);
1407
1408    /* spectral extension */
1409    if (s->eac3)
1410        put_bits(&s->pb, 1, 0);
1411
1412    /* channel coupling */
1413    if (!s->eac3)
1414        put_bits(&s->pb, 1, block->new_cpl_strategy);
1415    if (block->new_cpl_strategy) {
1416        if (!s->eac3)
1417            put_bits(&s->pb, 1, block->cpl_in_use);
1418        if (block->cpl_in_use) {
1419            int start_sub, end_sub;
1420            if (s->eac3)
1421                put_bits(&s->pb, 1, 0); /* enhanced coupling */
1422            if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
1423                for (ch = 1; ch <= s->fbw_channels; ch++)
1424                    put_bits(&s->pb, 1, block->channel_in_cpl[ch]);
1425            }
1426            if (s->channel_mode == AC3_CHMODE_STEREO)
1427                put_bits(&s->pb, 1, 0); /* phase flags in use */
1428            start_sub = (s->start_freq[CPL_CH] - 37) / 12;
1429            end_sub   = (s->cpl_end_freq       - 37) / 12;
1430            put_bits(&s->pb, 4, start_sub);
1431            put_bits(&s->pb, 4, end_sub - 3);
1432            /* coupling band structure */
1433            if (s->eac3) {
1434                put_bits(&s->pb, 1, 0); /* use default */
1435            } else {
1436                for (bnd = start_sub+1; bnd < end_sub; bnd++)
1437                    put_bits(&s->pb, 1, ff_eac3_default_cpl_band_struct[bnd]);
1438            }
1439        }
1440    }
1441
1442    /* coupling coordinates */
1443    if (block->cpl_in_use) {
1444        for (ch = 1; ch <= s->fbw_channels; ch++) {
1445            if (block->channel_in_cpl[ch]) {
1446                if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1447                    put_bits(&s->pb, 1, block->new_cpl_coords[ch]);
1448                if (block->new_cpl_coords[ch]) {
1449                    put_bits(&s->pb, 2, block->cpl_master_exp[ch]);
1450                    for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
1451                        put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);
1452                        put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]);
1453                    }
1454                }
1455            }
1456        }
1457    }
1458
1459    /* stereo rematrixing */
1460    if (s->channel_mode == AC3_CHMODE_STEREO) {
1461        if (!s->eac3 || blk > 0)
1462            put_bits(&s->pb, 1, block->new_rematrixing_strategy);
1463        if (block->new_rematrixing_strategy) {
1464            /* rematrixing flags */
1465            for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
1466                put_bits(&s->pb, 1, block->rematrixing_flags[bnd]);
1467        }
1468    }
1469
1470    /* exponent strategy */
1471    if (!s->eac3) {
1472        for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
1473            put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
1474        if (s->lfe_on)
1475            put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
1476    }
1477
1478    /* bandwidth */
1479    for (ch = 1; ch <= s->fbw_channels; ch++) {
1480        if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
1481            put_bits(&s->pb, 6, s->bandwidth_code);
1482    }
1483
1484    /* exponents */
1485    for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1486        int nb_groups;
1487        int cpl = (ch == CPL_CH);
1488
1489        if (s->exp_strategy[ch][blk] == EXP_REUSE)
1490            continue;
1491
1492        /* DC exponent */
1493        put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl);
1494
1495        /* exponent groups */
1496        nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
1497        for (i = 1; i <= nb_groups; i++)
1498            put_bits(&s->pb, 7, block->grouped_exp[ch][i]);
1499
1500        /* gain range info */
1501        if (ch != s->lfe_channel && !cpl)
1502            put_bits(&s->pb, 2, 0);
1503    }
1504
1505    /* bit allocation info */
1506    if (!s->eac3) {
1507        baie = (blk == 0);
1508        put_bits(&s->pb, 1, baie);
1509        if (baie) {
1510            put_bits(&s->pb, 2, s->slow_decay_code);
1511            put_bits(&s->pb, 2, s->fast_decay_code);
1512            put_bits(&s->pb, 2, s->slow_gain_code);
1513            put_bits(&s->pb, 2, s->db_per_bit_code);
1514            put_bits(&s->pb, 3, s->floor_code);
1515        }
1516    }
1517
1518    /* snr offset */
1519    if (!s->eac3) {
1520        put_bits(&s->pb, 1, block->new_snr_offsets);
1521        if (block->new_snr_offsets) {
1522            put_bits(&s->pb, 6, s->coarse_snr_offset);
1523            for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1524                put_bits(&s->pb, 4, s->fine_snr_offset[ch]);
1525                put_bits(&s->pb, 3, s->fast_gain_code[ch]);
1526            }
1527        }
1528    } else {
1529        put_bits(&s->pb, 1, 0); /* no converter snr offset */
1530    }
1531
1532    /* coupling leak */
1533    if (block->cpl_in_use) {
1534        if (!s->eac3 || block->new_cpl_leak != 2)
1535            put_bits(&s->pb, 1, block->new_cpl_leak);
1536        if (block->new_cpl_leak) {
1537            put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak);
1538            put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak);
1539        }
1540    }
1541
1542    if (!s->eac3) {
1543        put_bits(&s->pb, 1, 0); /* no delta bit allocation */
1544        put_bits(&s->pb, 1, 0); /* no data to skip */
1545    }
1546
1547    /* mantissas */
1548    got_cpl = !block->cpl_in_use;
1549    for (ch = 1; ch <= s->channels; ch++) {
1550        int b, q;
1551
1552        if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1553            ch0     = ch - 1;
1554            ch      = CPL_CH;
1555            got_cpl = 1;
1556        }
1557        for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
1558            q = block->qmant[ch][i];
1559            b = s->ref_bap[ch][blk][i];
1560            switch (b) {
1561            case 0:                                          break;
1562            case 1: if (q != 128) put_bits (&s->pb,   5, q); break;
1563            case 2: if (q != 128) put_bits (&s->pb,   7, q); break;
1564            case 3:               put_sbits(&s->pb,   3, q); break;
1565            case 4: if (q != 128) put_bits (&s->pb,   7, q); break;
1566            case 14:              put_sbits(&s->pb,  14, q); break;
1567            case 15:              put_sbits(&s->pb,  16, q); break;
1568            default:              put_sbits(&s->pb, b-1, q); break;
1569            }
1570        }
1571        if (ch == CPL_CH)
1572            ch = ch0;
1573    }
1574}
1575
1576
1577/** CRC-16 Polynomial */
1578#define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
1579
1580
1581static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
1582{
1583    unsigned int c;
1584
1585    c = 0;
1586    while (a) {
1587        if (a & 1)
1588            c ^= b;
1589        a = a >> 1;
1590        b = b << 1;
1591        if (b & (1 << 16))
1592            b ^= poly;
1593    }
1594    return c;
1595}
1596
1597
1598static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
1599{
1600    unsigned int r;
1601    r = 1;
1602    while (n) {
1603        if (n & 1)
1604            r = mul_poly(r, a, poly);
1605        a = mul_poly(a, a, poly);
1606        n >>= 1;
1607    }
1608    return r;
1609}
1610
1611
1612/*
1613 * Fill the end of the frame with 0's and compute the two CRCs.
1614 */
1615static void output_frame_end(AC3EncodeContext *s)
1616{
1617    const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
1618    int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv;
1619    uint8_t *frame;
1620
1621    frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
1622
1623    /* pad the remainder of the frame with zeros */
1624    av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18);
1625    flush_put_bits(&s->pb);
1626    frame = s->pb.buf;
1627    pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;
1628    av_assert2(pad_bytes >= 0);
1629    if (pad_bytes > 0)
1630        memset(put_bits_ptr(&s->pb), 0, pad_bytes);
1631
1632    if (s->eac3) {
1633        /* compute crc2 */
1634        crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5);
1635    } else {
1636    /* compute crc1 */
1637    /* this is not so easy because it is at the beginning of the data... */
1638    crc1    = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
1639    crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
1640    crc1    = mul_poly(crc_inv, crc1, CRC16_POLY);
1641    AV_WB16(frame + 2, crc1);
1642
1643    /* compute crc2 */
1644    crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58,
1645                          s->frame_size - frame_size_58 - 3);
1646    }
1647    crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1648    /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
1649    if (crc2 == 0x770B) {
1650        frame[s->frame_size - 3] ^= 0x1;
1651        crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);
1652    }
1653    crc2 = av_bswap16(crc2);
1654    AV_WB16(frame + s->frame_size - 2, crc2);
1655}
1656
1657
1658/**
1659 * Write the frame to the output bitstream.
1660 *
1661 * @param s      AC-3 encoder private context
1662 * @param frame  output data buffer
1663 */
1664void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
1665{
1666    int blk;
1667
1668    init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);
1669
1670    s->output_frame_header(s);
1671
1672    for (blk = 0; blk < s->num_blocks; blk++)
1673        output_audio_block(s, blk);
1674
1675    output_frame_end(s);
1676}
1677
1678
1679static void dprint_options(AC3EncodeContext *s)
1680{
1681#ifdef DEBUG
1682    AVCodecContext *avctx = s->avctx;
1683    AC3EncOptions *opt = &s->options;
1684    char strbuf[32];
1685
1686    switch (s->bitstream_id) {
1687    case  6:  av_strlcpy(strbuf, "AC-3 (alt syntax)",       32); break;
1688    case  8:  av_strlcpy(strbuf, "AC-3 (standard)",         32); break;
1689    case  9:  av_strlcpy(strbuf, "AC-3 (dnet half-rate)",   32); break;
1690    case 10:  av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break;
1691    case 16:  av_strlcpy(strbuf, "E-AC-3 (enhanced)",       32); break;
1692    default: snprintf(strbuf, 32, "ERROR");
1693    }
1694    av_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id);
1695    av_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
1696    av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout);
1697    av_dlog(avctx, "channel_layout: %s\n", strbuf);
1698    av_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
1699    av_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
1700    av_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
1701    if (s->cutoff)
1702        av_dlog(avctx, "cutoff: %d\n", s->cutoff);
1703
1704    av_dlog(avctx, "per_frame_metadata: %s\n",
1705            opt->allow_per_frame_metadata?"on":"off");
1706    if (s->has_center)
1707        av_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
1708                s->center_mix_level);
1709    else
1710        av_dlog(avctx, "center_mixlev: {not written}\n");
1711    if (s->has_surround)
1712        av_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
1713                s->surround_mix_level);
1714    else
1715        av_dlog(avctx, "surround_mixlev: {not written}\n");
1716    if (opt->audio_production_info) {
1717        av_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
1718        switch (opt->room_type) {
1719        case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1720        case AC3ENC_OPT_LARGE_ROOM:    av_strlcpy(strbuf, "large", 32);        break;
1721        case AC3ENC_OPT_SMALL_ROOM:    av_strlcpy(strbuf, "small", 32);        break;
1722        default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type);
1723        }
1724        av_dlog(avctx, "room_type: %s\n", strbuf);
1725    } else {
1726        av_dlog(avctx, "mixing_level: {not written}\n");
1727        av_dlog(avctx, "room_type: {not written}\n");
1728    }
1729    av_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
1730    av_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
1731    if (s->channel_mode == AC3_CHMODE_STEREO) {
1732        switch (opt->dolby_surround_mode) {
1733        case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1734        case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
1735        case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
1736        default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode);
1737        }
1738        av_dlog(avctx, "dsur_mode: %s\n", strbuf);
1739    } else {
1740        av_dlog(avctx, "dsur_mode: {not written}\n");
1741    }
1742    av_dlog(avctx, "original: %s\n", opt->original?"on":"off");
1743
1744    if (s->bitstream_id == 6) {
1745        if (opt->extended_bsi_1) {
1746            switch (opt->preferred_stereo_downmix) {
1747            case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1748            case AC3ENC_OPT_DOWNMIX_LTRT:  av_strlcpy(strbuf, "ltrt", 32);         break;
1749            case AC3ENC_OPT_DOWNMIX_LORO:  av_strlcpy(strbuf, "loro", 32);         break;
1750            default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix);
1751            }
1752            av_dlog(avctx, "dmix_mode: %s\n", strbuf);
1753            av_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
1754                    opt->ltrt_center_mix_level, s->ltrt_center_mix_level);
1755            av_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
1756                    opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level);
1757            av_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
1758                    opt->loro_center_mix_level, s->loro_center_mix_level);
1759            av_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
1760                    opt->loro_surround_mix_level, s->loro_surround_mix_level);
1761        } else {
1762            av_dlog(avctx, "extended bitstream info 1: {not written}\n");
1763        }
1764        if (opt->extended_bsi_2) {
1765            switch (opt->dolby_surround_ex_mode) {
1766            case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1767            case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
1768            case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
1769            default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode);
1770            }
1771            av_dlog(avctx, "dsurex_mode: %s\n", strbuf);
1772            switch (opt->dolby_headphone_mode) {
1773            case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;
1774            case AC3ENC_OPT_MODE_ON:       av_strlcpy(strbuf, "on", 32);           break;
1775            case AC3ENC_OPT_MODE_OFF:      av_strlcpy(strbuf, "off", 32);          break;
1776            default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode);
1777            }
1778            av_dlog(avctx, "dheadphone_mode: %s\n", strbuf);
1779
1780            switch (opt->ad_converter_type) {
1781            case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break;
1782            case AC3ENC_OPT_ADCONV_HDCD:     av_strlcpy(strbuf, "hdcd", 32);     break;
1783            default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type);
1784            }
1785            av_dlog(avctx, "ad_conv_type: %s\n", strbuf);
1786        } else {
1787            av_dlog(avctx, "extended bitstream info 2: {not written}\n");
1788        }
1789    }
1790#endif
1791}
1792
1793
1794#define FLT_OPTION_THRESHOLD 0.01
1795
1796static int validate_float_option(float v, const float *v_list, int v_list_size)
1797{
1798    int i;
1799
1800    for (i = 0; i < v_list_size; i++) {
1801        if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
1802            v > (v_list[i] - FLT_OPTION_THRESHOLD))
1803            break;
1804    }
1805    if (i == v_list_size)
1806        return -1;
1807
1808    return i;
1809}
1810
1811
1812static void validate_mix_level(void *log_ctx, const char *opt_name,
1813                               float *opt_param, const float *list,
1814                               int list_size, int default_value, int min_value,
1815                               int *ctx_param)
1816{
1817    int mixlev = validate_float_option(*opt_param, list, list_size);
1818    if (mixlev < min_value) {
1819        mixlev = default_value;
1820        if (*opt_param >= 0.0) {
1821            av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
1822                   "default value: %0.3f\n", opt_name, list[mixlev]);
1823        }
1824    }
1825    *opt_param = list[mixlev];
1826    *ctx_param = mixlev;
1827}
1828
1829
1830/**
1831 * Validate metadata options as set by AVOption system.
1832 * These values can optionally be changed per-frame.
1833 *
1834 * @param s  AC-3 encoder private context
1835 */
1836int ff_ac3_validate_metadata(AC3EncodeContext *s)
1837{
1838    AVCodecContext *avctx = s->avctx;
1839    AC3EncOptions *opt = &s->options;
1840
1841    opt->audio_production_info = 0;
1842    opt->extended_bsi_1        = 0;
1843    opt->extended_bsi_2        = 0;
1844    opt->eac3_mixing_metadata  = 0;
1845    opt->eac3_info_metadata    = 0;
1846
1847    /* determine mixing metadata / xbsi1 use */
1848    if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) {
1849        opt->extended_bsi_1       = 1;
1850        opt->eac3_mixing_metadata = 1;
1851    }
1852    if (s->has_center &&
1853        (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
1854        opt->extended_bsi_1       = 1;
1855        opt->eac3_mixing_metadata = 1;
1856    }
1857    if (s->has_surround &&
1858        (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
1859        opt->extended_bsi_1       = 1;
1860        opt->eac3_mixing_metadata = 1;
1861    }
1862
1863    if (s->eac3) {
1864        /* determine info metadata use */
1865        if (avctx->audio_service_type != AV_AUDIO_SERVICE_TYPE_MAIN)
1866            opt->eac3_info_metadata = 1;
1867        if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
1868            opt->eac3_info_metadata = 1;
1869        if (s->channel_mode == AC3_CHMODE_STEREO &&
1870            (opt->dolby_headphone_mode != AC3ENC_OPT_NONE || opt->dolby_surround_mode != AC3ENC_OPT_NONE))
1871            opt->eac3_info_metadata = 1;
1872        if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
1873            opt->eac3_info_metadata = 1;
1874        if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
1875            opt->ad_converter_type != AC3ENC_OPT_NONE) {
1876            opt->audio_production_info = 1;
1877            opt->eac3_info_metadata    = 1;
1878        }
1879    } else {
1880        /* determine audio production info use */
1881        if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
1882            opt->audio_production_info = 1;
1883
1884        /* determine xbsi2 use */
1885        if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
1886            opt->extended_bsi_2 = 1;
1887        if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE)
1888            opt->extended_bsi_2 = 1;
1889        if (opt->ad_converter_type != AC3ENC_OPT_NONE)
1890            opt->extended_bsi_2 = 1;
1891    }
1892
1893    /* validate AC-3 mixing levels */
1894    if (!s->eac3) {
1895        if (s->has_center) {
1896            validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
1897                            cmixlev_options, CMIXLEV_NUM_OPTIONS, 1, 0,
1898                            &s->center_mix_level);
1899        }
1900        if (s->has_surround) {
1901            validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
1902                            surmixlev_options, SURMIXLEV_NUM_OPTIONS, 1, 0,
1903                            &s->surround_mix_level);
1904        }
1905    }
1906
1907    /* validate extended bsi 1 / mixing metadata */
1908    if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
1909        /* default preferred stereo downmix */
1910        if (opt->preferred_stereo_downmix == AC3ENC_OPT_NONE)
1911            opt->preferred_stereo_downmix = AC3ENC_OPT_NOT_INDICATED;
1912        if (!s->eac3 || s->has_center) {
1913            /* validate Lt/Rt center mix level */
1914            validate_mix_level(avctx, "ltrt_center_mix_level",
1915                               &opt->ltrt_center_mix_level, extmixlev_options,
1916                               EXTMIXLEV_NUM_OPTIONS, 5, 0,
1917                               &s->ltrt_center_mix_level);
1918            /* validate Lo/Ro center mix level */
1919            validate_mix_level(avctx, "loro_center_mix_level",
1920                               &opt->loro_center_mix_level, extmixlev_options,
1921                               EXTMIXLEV_NUM_OPTIONS, 5, 0,
1922                               &s->loro_center_mix_level);
1923        }
1924        if (!s->eac3 || s->has_surround) {
1925            /* validate Lt/Rt surround mix level */
1926            validate_mix_level(avctx, "ltrt_surround_mix_level",
1927                               &opt->ltrt_surround_mix_level, extmixlev_options,
1928                               EXTMIXLEV_NUM_OPTIONS, 6, 3,
1929                               &s->ltrt_surround_mix_level);
1930            /* validate Lo/Ro surround mix level */
1931            validate_mix_level(avctx, "loro_surround_mix_level",
1932                               &opt->loro_surround_mix_level, extmixlev_options,
1933                               EXTMIXLEV_NUM_OPTIONS, 6, 3,
1934                               &s->loro_surround_mix_level);
1935        }
1936    }
1937
1938    /* validate audio service type / channels combination */
1939    if ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_KARAOKE &&
1940         avctx->channels == 1) ||
1941        ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_COMMENTARY ||
1942          avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_EMERGENCY  ||
1943          avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_VOICE_OVER)
1944         && avctx->channels > 1)) {
1945        av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
1946                                    "specified number of channels\n");
1947        return AVERROR(EINVAL);
1948    }
1949
1950    /* validate extended bsi 2 / info metadata */
1951    if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
1952        /* default dolby headphone mode */
1953        if (opt->dolby_headphone_mode == AC3ENC_OPT_NONE)
1954            opt->dolby_headphone_mode = AC3ENC_OPT_NOT_INDICATED;
1955        /* default dolby surround ex mode */
1956        if (opt->dolby_surround_ex_mode == AC3ENC_OPT_NONE)
1957            opt->dolby_surround_ex_mode = AC3ENC_OPT_NOT_INDICATED;
1958        /* default A/D converter type */
1959        if (opt->ad_converter_type == AC3ENC_OPT_NONE)
1960            opt->ad_converter_type = AC3ENC_OPT_ADCONV_STANDARD;
1961    }
1962
1963    /* copyright & original defaults */
1964    if (!s->eac3 || opt->eac3_info_metadata) {
1965        /* default copyright */
1966        if (opt->copyright == AC3ENC_OPT_NONE)
1967            opt->copyright = AC3ENC_OPT_OFF;
1968        /* default original */
1969        if (opt->original == AC3ENC_OPT_NONE)
1970            opt->original = AC3ENC_OPT_ON;
1971    }
1972
1973    /* dolby surround mode default */
1974    if (!s->eac3 || opt->eac3_info_metadata) {
1975        if (opt->dolby_surround_mode == AC3ENC_OPT_NONE)
1976            opt->dolby_surround_mode = AC3ENC_OPT_NOT_INDICATED;
1977    }
1978
1979    /* validate audio production info */
1980    if (opt->audio_production_info) {
1981        if (opt->mixing_level == AC3ENC_OPT_NONE) {
1982            av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
1983                   "room_type is set\n");
1984            return AVERROR(EINVAL);
1985        }
1986        if (opt->mixing_level < 80) {
1987            av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
1988                   "80dB and 111dB\n");
1989            return AVERROR(EINVAL);
1990        }
1991        /* default room type */
1992        if (opt->room_type == AC3ENC_OPT_NONE)
1993            opt->room_type = AC3ENC_OPT_NOT_INDICATED;
1994    }
1995
1996    /* set bitstream id for alternate bitstream syntax */
1997    if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {
1998        if (s->bitstream_id > 8 && s->bitstream_id < 11) {
1999            static int warn_once = 1;
2000            if (warn_once) {
2001                av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "
2002                       "not compatible with reduced samplerates. writing of "
2003                       "extended bitstream information will be disabled.\n");
2004                warn_once = 0;
2005            }
2006        } else {
2007            s->bitstream_id = 6;
2008        }
2009    }
2010
2011    return 0;
2012}
2013
2014
2015/**
2016 * Finalize encoding and free any memory allocated by the encoder.
2017 *
2018 * @param avctx  Codec context
2019 */
2020av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
2021{
2022    int blk, ch;
2023    AC3EncodeContext *s = avctx->priv_data;
2024
2025    av_freep(&s->windowed_samples);
2026    for (ch = 0; ch < s->channels; ch++)
2027        av_freep(&s->planar_samples[ch]);
2028    av_freep(&s->planar_samples);
2029    av_freep(&s->bap_buffer);
2030    av_freep(&s->bap1_buffer);
2031    av_freep(&s->mdct_coef_buffer);
2032    av_freep(&s->fixed_coef_buffer);
2033    av_freep(&s->exp_buffer);
2034    av_freep(&s->grouped_exp_buffer);
2035    av_freep(&s->psd_buffer);
2036    av_freep(&s->band_psd_buffer);
2037    av_freep(&s->mask_buffer);
2038    av_freep(&s->qmant_buffer);
2039    av_freep(&s->cpl_coord_exp_buffer);
2040    av_freep(&s->cpl_coord_mant_buffer);
2041    for (blk = 0; blk < s->num_blocks; blk++) {
2042        AC3Block *block = &s->blocks[blk];
2043        av_freep(&block->mdct_coef);
2044        av_freep(&block->fixed_coef);
2045        av_freep(&block->exp);
2046        av_freep(&block->grouped_exp);
2047        av_freep(&block->psd);
2048        av_freep(&block->band_psd);
2049        av_freep(&block->mask);
2050        av_freep(&block->qmant);
2051        av_freep(&block->cpl_coord_exp);
2052        av_freep(&block->cpl_coord_mant);
2053    }
2054
2055    s->mdct_end(s);
2056
2057    av_freep(&avctx->coded_frame);
2058    return 0;
2059}
2060
2061
2062/*
2063 * Set channel information during initialization.
2064 */
2065static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
2066                                    uint64_t *channel_layout)
2067{
2068    int ch_layout;
2069
2070    if (channels < 1 || channels > AC3_MAX_CHANNELS)
2071        return AVERROR(EINVAL);
2072    if (*channel_layout > 0x7FF)
2073        return AVERROR(EINVAL);
2074    ch_layout = *channel_layout;
2075    if (!ch_layout)
2076        ch_layout = avcodec_guess_channel_layout(channels, CODEC_ID_AC3, NULL);
2077
2078    s->lfe_on       = !!(ch_layout & AV_CH_LOW_FREQUENCY);
2079    s->channels     = channels;
2080    s->fbw_channels = channels - s->lfe_on;
2081    s->lfe_channel  = s->lfe_on ? s->fbw_channels + 1 : -1;
2082    if (s->lfe_on)
2083        ch_layout -= AV_CH_LOW_FREQUENCY;
2084
2085    switch (ch_layout) {
2086    case AV_CH_LAYOUT_MONO:           s->channel_mode = AC3_CHMODE_MONO;   break;
2087    case AV_CH_LAYOUT_STEREO:         s->channel_mode = AC3_CHMODE_STEREO; break;
2088    case AV_CH_LAYOUT_SURROUND:       s->channel_mode = AC3_CHMODE_3F;     break;
2089    case AV_CH_LAYOUT_2_1:            s->channel_mode = AC3_CHMODE_2F1R;   break;
2090    case AV_CH_LAYOUT_4POINT0:        s->channel_mode = AC3_CHMODE_3F1R;   break;
2091    case AV_CH_LAYOUT_QUAD:
2092    case AV_CH_LAYOUT_2_2:            s->channel_mode = AC3_CHMODE_2F2R;   break;
2093    case AV_CH_LAYOUT_5POINT0:
2094    case AV_CH_LAYOUT_5POINT0_BACK:   s->channel_mode = AC3_CHMODE_3F2R;   break;
2095    default:
2096        return AVERROR(EINVAL);
2097    }
2098    s->has_center   = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
2099    s->has_surround =  s->channel_mode & 0x04;
2100
2101    s->channel_map  = ff_ac3_enc_channel_map[s->channel_mode][s->lfe_on];
2102    *channel_layout = ch_layout;
2103    if (s->lfe_on)
2104        *channel_layout |= AV_CH_LOW_FREQUENCY;
2105
2106    return 0;
2107}
2108
2109
2110static av_cold int validate_options(AC3EncodeContext *s)
2111{
2112    AVCodecContext *avctx = s->avctx;
2113    int i, ret, max_sr;
2114
2115    /* validate channel layout */
2116    if (!avctx->channel_layout) {
2117        av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "
2118                                      "encoder will guess the layout, but it "
2119                                      "might be incorrect.\n");
2120    }
2121    ret = set_channel_info(s, avctx->channels, &avctx->channel_layout);
2122    if (ret) {
2123        av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");
2124        return ret;
2125    }
2126
2127    /* validate sample rate */
2128    /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a
2129             decoder that supports half sample rate so we can validate that
2130             the generated files are correct. */
2131    max_sr = s->eac3 ? 2 : 8;
2132    for (i = 0; i <= max_sr; i++) {
2133        if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)
2134            break;
2135    }
2136    if (i > max_sr) {
2137        av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
2138        return AVERROR(EINVAL);
2139    }
2140    s->sample_rate        = avctx->sample_rate;
2141    s->bit_alloc.sr_shift = i / 3;
2142    s->bit_alloc.sr_code  = i % 3;
2143    s->bitstream_id       = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;
2144
2145    /* validate bit rate */
2146    if (s->eac3) {
2147        int max_br, min_br, wpf, min_br_dist, min_br_code;
2148        int num_blks_code, num_blocks, frame_samples;
2149
2150        /* calculate min/max bitrate */
2151        /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
2152                 found use either 6 blocks or 1 block, even though 2 or 3 blocks
2153                 would work as far as the bit rate is concerned. */
2154        for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
2155            num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
2156            frame_samples  = AC3_BLOCK_SIZE * num_blocks;
2157            max_br = 2048 * s->sample_rate / frame_samples * 16;
2158            min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
2159            if (avctx->bit_rate <= max_br)
2160                break;
2161        }
2162        if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
2163            av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
2164                   "for this sample rate\n", min_br, max_br);
2165            return AVERROR(EINVAL);
2166        }
2167        s->num_blks_code = num_blks_code;
2168        s->num_blocks    = num_blocks;
2169
2170        /* calculate words-per-frame for the selected bitrate */
2171        wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
2172        av_assert1(wpf > 0 && wpf <= 2048);
2173
2174        /* find the closest AC-3 bitrate code to the selected bitrate.
2175           this is needed for lookup tables for bandwidth and coupling
2176           parameter selection */
2177        min_br_code = -1;
2178        min_br_dist = INT_MAX;
2179        for (i = 0; i < 19; i++) {
2180            int br_dist = abs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
2181            if (br_dist < min_br_dist) {
2182                min_br_dist = br_dist;
2183                min_br_code = i;
2184            }
2185        }
2186
2187        /* make sure the minimum frame size is below the average frame size */
2188        s->frame_size_code = min_br_code << 1;
2189        while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
2190            wpf--;
2191        s->frame_size_min = 2 * wpf;
2192    } else {
2193        for (i = 0; i < 19; i++) {
2194            if ((ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift)*1000 == avctx->bit_rate)
2195                break;
2196        }
2197        if (i == 19) {
2198            av_log(avctx, AV_LOG_ERROR, "invalid bit rate\n");
2199            return AVERROR(EINVAL);
2200        }
2201        s->frame_size_code = i << 1;
2202        s->frame_size_min  = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
2203        s->num_blks_code   = 0x3;
2204        s->num_blocks      = 6;
2205    }
2206    s->bit_rate   = avctx->bit_rate;
2207    s->frame_size = s->frame_size_min;
2208
2209    /* validate cutoff */
2210    if (avctx->cutoff < 0) {
2211        av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
2212        return AVERROR(EINVAL);
2213    }
2214    s->cutoff = avctx->cutoff;
2215    if (s->cutoff > (s->sample_rate >> 1))
2216        s->cutoff = s->sample_rate >> 1;
2217
2218    ret = ff_ac3_validate_metadata(s);
2219    if (ret)
2220        return ret;
2221
2222    s->rematrixing_enabled = s->options.stereo_rematrixing &&
2223                             (s->channel_mode == AC3_CHMODE_STEREO);
2224
2225    s->cpl_enabled = s->options.channel_coupling &&
2226                     s->channel_mode >= AC3_CHMODE_STEREO;
2227
2228    return 0;
2229}
2230
2231
2232/*
2233 * Set bandwidth for all channels.
2234 * The user can optionally supply a cutoff frequency. Otherwise an appropriate
2235 * default value will be used.
2236 */
2237static av_cold void set_bandwidth(AC3EncodeContext *s)
2238{
2239    int blk, ch;
2240    int av_uninit(cpl_start);
2241
2242    if (s->cutoff) {
2243        /* calculate bandwidth based on user-specified cutoff frequency */
2244        int fbw_coeffs;
2245        fbw_coeffs     = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
2246        s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
2247    } else {
2248        /* use default bandwidth setting */
2249        s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
2250    }
2251
2252    /* set number of coefficients for each channel */
2253    for (ch = 1; ch <= s->fbw_channels; ch++) {
2254        s->start_freq[ch] = 0;
2255        for (blk = 0; blk < s->num_blocks; blk++)
2256            s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
2257    }
2258    /* LFE channel always has 7 coefs */
2259    if (s->lfe_on) {
2260        s->start_freq[s->lfe_channel] = 0;
2261        for (blk = 0; blk < s->num_blocks; blk++)
2262            s->blocks[blk].end_freq[ch] = 7;
2263    }
2264
2265    /* initialize coupling strategy */
2266    if (s->cpl_enabled) {
2267        if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
2268            cpl_start = s->options.cpl_start;
2269        } else {
2270            cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
2271            if (cpl_start < 0) {
2272                if (s->options.channel_coupling == AC3ENC_OPT_AUTO)
2273                    s->cpl_enabled = 0;
2274                else
2275                    cpl_start = 15;
2276            }
2277        }
2278    }
2279    if (s->cpl_enabled) {
2280        int i, cpl_start_band, cpl_end_band;
2281        uint8_t *cpl_band_sizes = s->cpl_band_sizes;
2282
2283        cpl_end_band   = s->bandwidth_code / 4 + 3;
2284        cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
2285
2286        s->num_cpl_subbands = cpl_end_band - cpl_start_band;
2287
2288        s->num_cpl_bands = 1;
2289        *cpl_band_sizes  = 12;
2290        for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
2291            if (ff_eac3_default_cpl_band_struct[i]) {
2292                *cpl_band_sizes += 12;
2293            } else {
2294                s->num_cpl_bands++;
2295                cpl_band_sizes++;
2296                *cpl_band_sizes = 12;
2297            }
2298        }
2299
2300        s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
2301        s->cpl_end_freq       = cpl_end_band   * 12 + 37;
2302        for (blk = 0; blk < s->num_blocks; blk++)
2303            s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
2304    }
2305}
2306
2307
2308static av_cold int allocate_buffers(AC3EncodeContext *s)
2309{
2310    AVCodecContext *avctx = s->avctx;
2311    int blk, ch;
2312    int channels = s->channels + 1; /* includes coupling channel */
2313    int channel_blocks = channels * s->num_blocks;
2314    int total_coefs    = AC3_MAX_COEFS * channel_blocks;
2315
2316    if (s->allocate_sample_buffers(s))
2317        goto alloc_fail;
2318
2319    FF_ALLOC_OR_GOTO(avctx, s->bap_buffer, total_coefs *
2320                     sizeof(*s->bap_buffer), alloc_fail);
2321    FF_ALLOC_OR_GOTO(avctx, s->bap1_buffer, total_coefs *
2322                     sizeof(*s->bap1_buffer), alloc_fail);
2323    FF_ALLOCZ_OR_GOTO(avctx, s->mdct_coef_buffer, total_coefs *
2324                      sizeof(*s->mdct_coef_buffer), alloc_fail);
2325    FF_ALLOC_OR_GOTO(avctx, s->exp_buffer, total_coefs *
2326                     sizeof(*s->exp_buffer), alloc_fail);
2327    FF_ALLOC_OR_GOTO(avctx, s->grouped_exp_buffer, channel_blocks * 128 *
2328                     sizeof(*s->grouped_exp_buffer), alloc_fail);
2329    FF_ALLOC_OR_GOTO(avctx, s->psd_buffer, total_coefs *
2330                     sizeof(*s->psd_buffer), alloc_fail);
2331    FF_ALLOC_OR_GOTO(avctx, s->band_psd_buffer, channel_blocks * 64 *
2332                     sizeof(*s->band_psd_buffer), alloc_fail);
2333    FF_ALLOC_OR_GOTO(avctx, s->mask_buffer, channel_blocks * 64 *
2334                     sizeof(*s->mask_buffer), alloc_fail);
2335    FF_ALLOC_OR_GOTO(avctx, s->qmant_buffer, total_coefs *
2336                     sizeof(*s->qmant_buffer), alloc_fail);
2337    if (s->cpl_enabled) {
2338        FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_exp_buffer, channel_blocks * 16 *
2339                         sizeof(*s->cpl_coord_exp_buffer), alloc_fail);
2340        FF_ALLOC_OR_GOTO(avctx, s->cpl_coord_mant_buffer, channel_blocks * 16 *
2341                         sizeof(*s->cpl_coord_mant_buffer), alloc_fail);
2342    }
2343    for (blk = 0; blk < s->num_blocks; blk++) {
2344        AC3Block *block = &s->blocks[blk];
2345        FF_ALLOCZ_OR_GOTO(avctx, block->mdct_coef, channels * sizeof(*block->mdct_coef),
2346                          alloc_fail);
2347        FF_ALLOCZ_OR_GOTO(avctx, block->exp, channels * sizeof(*block->exp),
2348                          alloc_fail);
2349        FF_ALLOCZ_OR_GOTO(avctx, block->grouped_exp, channels * sizeof(*block->grouped_exp),
2350                          alloc_fail);
2351        FF_ALLOCZ_OR_GOTO(avctx, block->psd, channels * sizeof(*block->psd),
2352                          alloc_fail);
2353        FF_ALLOCZ_OR_GOTO(avctx, block->band_psd, channels * sizeof(*block->band_psd),
2354                          alloc_fail);
2355        FF_ALLOCZ_OR_GOTO(avctx, block->mask, channels * sizeof(*block->mask),
2356                          alloc_fail);
2357        FF_ALLOCZ_OR_GOTO(avctx, block->qmant, channels * sizeof(*block->qmant),
2358                          alloc_fail);
2359        if (s->cpl_enabled) {
2360            FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_exp, channels * sizeof(*block->cpl_coord_exp),
2361                              alloc_fail);
2362            FF_ALLOCZ_OR_GOTO(avctx, block->cpl_coord_mant, channels * sizeof(*block->cpl_coord_mant),
2363                              alloc_fail);
2364        }
2365
2366        for (ch = 0; ch < channels; ch++) {
2367            /* arrangement: block, channel, coeff */
2368            block->grouped_exp[ch] = &s->grouped_exp_buffer[128           * (blk * channels + ch)];
2369            block->psd[ch]         = &s->psd_buffer        [AC3_MAX_COEFS * (blk * channels + ch)];
2370            block->band_psd[ch]    = &s->band_psd_buffer   [64            * (blk * channels + ch)];
2371            block->mask[ch]        = &s->mask_buffer       [64            * (blk * channels + ch)];
2372            block->qmant[ch]       = &s->qmant_buffer      [AC3_MAX_COEFS * (blk * channels + ch)];
2373            if (s->cpl_enabled) {
2374                block->cpl_coord_exp[ch]  = &s->cpl_coord_exp_buffer [16  * (blk * channels + ch)];
2375                block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16  * (blk * channels + ch)];
2376            }
2377
2378            /* arrangement: channel, block, coeff */
2379            block->exp[ch]         = &s->exp_buffer        [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2380            block->mdct_coef[ch]   = &s->mdct_coef_buffer  [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2381        }
2382    }
2383
2384    if (!s->fixed_point) {
2385        FF_ALLOCZ_OR_GOTO(avctx, s->fixed_coef_buffer, total_coefs *
2386                          sizeof(*s->fixed_coef_buffer), alloc_fail);
2387        for (blk = 0; blk < s->num_blocks; blk++) {
2388            AC3Block *block = &s->blocks[blk];
2389            FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
2390                              sizeof(*block->fixed_coef), alloc_fail);
2391            for (ch = 0; ch < channels; ch++)
2392                block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2393        }
2394    } else {
2395        for (blk = 0; blk < s->num_blocks; blk++) {
2396            AC3Block *block = &s->blocks[blk];
2397            FF_ALLOCZ_OR_GOTO(avctx, block->fixed_coef, channels *
2398                              sizeof(*block->fixed_coef), alloc_fail);
2399            for (ch = 0; ch < channels; ch++)
2400                block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
2401        }
2402    }
2403
2404    return 0;
2405alloc_fail:
2406    return AVERROR(ENOMEM);
2407}
2408
2409
2410av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
2411{
2412    AC3EncodeContext *s = avctx->priv_data;
2413    int ret, frame_size_58;
2414
2415    s->avctx = avctx;
2416
2417    s->eac3 = avctx->codec_id == CODEC_ID_EAC3;
2418
2419    ff_ac3_common_init();
2420
2421    ret = validate_options(s);
2422    if (ret)
2423        return ret;
2424
2425    avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
2426
2427    s->bitstream_mode = avctx->audio_service_type;
2428    if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE)
2429        s->bitstream_mode = 0x7;
2430
2431    s->bits_written    = 0;
2432    s->samples_written = 0;
2433
2434    /* calculate crc_inv for both possible frame sizes */
2435    frame_size_58 = (( s->frame_size    >> 2) + ( s->frame_size    >> 4)) << 1;
2436    s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2437    if (s->bit_alloc.sr_code == 1) {
2438        frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
2439        s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2440    }
2441
2442    /* set function pointers */
2443    if (CONFIG_AC3_FIXED_ENCODER && s->fixed_point) {
2444        s->mdct_end                     = ff_ac3_fixed_mdct_end;
2445        s->mdct_init                    = ff_ac3_fixed_mdct_init;
2446        s->allocate_sample_buffers      = ff_ac3_fixed_allocate_sample_buffers;
2447    } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {
2448        s->mdct_end                     = ff_ac3_float_mdct_end;
2449        s->mdct_init                    = ff_ac3_float_mdct_init;
2450        s->allocate_sample_buffers      = ff_ac3_float_allocate_sample_buffers;
2451    }
2452    if (CONFIG_EAC3_ENCODER && s->eac3)
2453        s->output_frame_header = ff_eac3_output_frame_header;
2454    else
2455        s->output_frame_header = ac3_output_frame_header;
2456
2457    set_bandwidth(s);
2458
2459    exponent_init(s);
2460
2461    bit_alloc_init(s);
2462
2463    ret = s->mdct_init(s);
2464    if (ret)
2465        goto init_fail;
2466
2467    ret = allocate_buffers(s);
2468    if (ret)
2469        goto init_fail;
2470
2471    avctx->coded_frame= avcodec_alloc_frame();
2472
2473    dsputil_init(&s->dsp, avctx);
2474    ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT);
2475
2476    dprint_options(s);
2477
2478    return 0;
2479init_fail:
2480    ff_ac3_encode_close(avctx);
2481    return ret;
2482}
2483