GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/ac3enc_template.c Lines: 193 217 88.9 %
Date: 2020-09-25 23:16:12 Branches: 122 154 79.2 %

Line Branch Exec Source
1
/*
2
 * AC-3 encoder float/fixed template
3
 * Copyright (c) 2000 Fabrice Bellard
4
 * Copyright (c) 2006-2011 Justin Ruggles <justin.ruggles@gmail.com>
5
 * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
6
 *
7
 * This file is part of FFmpeg.
8
 *
9
 * FFmpeg is free software; you can redistribute it and/or
10
 * modify it under the terms of the GNU Lesser General Public
11
 * License as published by the Free Software Foundation; either
12
 * version 2.1 of the License, or (at your option) any later version.
13
 *
14
 * FFmpeg is distributed in the hope that it will be useful,
15
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17
 * Lesser General Public License for more details.
18
 *
19
 * You should have received a copy of the GNU Lesser General Public
20
 * License along with FFmpeg; if not, write to the Free Software
21
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22
 */
23
24
/**
25
 * @file
26
 * AC-3 encoder float/fixed template
27
 */
28
29
#include <stdint.h>
30
31
#include "libavutil/attributes.h"
32
#include "libavutil/internal.h"
33
34
#include "audiodsp.h"
35
#include "internal.h"
36
#include "ac3enc.h"
37
#include "eac3enc.h"
38
39
40
6
int AC3_NAME(allocate_sample_buffers)(AC3EncodeContext *s)
41
{
42
    int ch;
43
44
6
    if (!FF_ALLOC_TYPED_ARRAY(s->windowed_samples, AC3_WINDOW_SIZE) ||
45
6
        !FF_ALLOCZ_TYPED_ARRAY(s->planar_samples,  s->channels))
46
        return AVERROR(ENOMEM);
47
48
15
    for (ch = 0; ch < s->channels; ch++) {
49
9
        if (!(s->planar_samples[ch] = av_mallocz((AC3_FRAME_SIZE + AC3_BLOCK_SIZE) *
50
                                                  sizeof(**s->planar_samples))))
51
            return AVERROR(ENOMEM);
52
    }
53
6
    return 0;
54
}
55
56
57
/*
58
 * Copy input samples.
59
 * Channels are reordered from FFmpeg's default order to AC-3 order.
60
 */
61
1097
static void copy_input_samples(AC3EncodeContext *s, SampleType **samples)
62
{
63
    int ch;
64
65
    /* copy and remap input samples */
66
2913
    for (ch = 0; ch < s->channels; ch++) {
67
        /* copy last 256 samples of previous frame to the start of the current frame */
68
1816
        memcpy(&s->planar_samples[ch][0], &s->planar_samples[ch][AC3_BLOCK_SIZE * s->num_blocks],
69
               AC3_BLOCK_SIZE * sizeof(s->planar_samples[0][0]));
70
71
        /* copy new samples for current frame */
72
1816
        memcpy(&s->planar_samples[ch][AC3_BLOCK_SIZE],
73
1816
               samples[s->channel_map[ch]],
74
1816
               AC3_BLOCK_SIZE * s->num_blocks * sizeof(s->planar_samples[0][0]));
75
    }
76
1097
}
77
78
79
/*
80
 * Apply the MDCT to input samples to generate frequency coefficients.
81
 * This applies the KBD window and normalizes the input to reduce precision
82
 * loss due to fixed-point calculations.
83
 */
84
1097
static void apply_mdct(AC3EncodeContext *s)
85
{
86
    int blk, ch;
87
88
2913
    for (ch = 0; ch < s->channels; ch++) {
89
12712
        for (blk = 0; blk < s->num_blocks; blk++) {
90
10896
            AC3Block *block = &s->blocks[blk];
91
10896
            const SampleType *input_samples = &s->planar_samples[ch][blk * AC3_BLOCK_SIZE];
92
93
#if CONFIG_AC3ENC_FLOAT
94
6552
            s->fdsp->vector_fmul(s->windowed_samples, input_samples,
95
6552
                                s->mdct_window, AC3_WINDOW_SIZE);
96
#else
97
4344
            s->ac3dsp.apply_window_int16(s->windowed_samples, input_samples,
98
4344
                                         s->mdct_window, AC3_WINDOW_SIZE);
99
100
4344
            if (s->fixed_point)
101
4344
                block->coeff_shift[ch+1] = normalize_samples(s);
102
#endif
103
104
10896
            s->mdct.mdct_calcw(&s->mdct, block->mdct_coef[ch+1],
105
10896
                               s->windowed_samples);
106
        }
107
    }
108
1097
}
109
110
111
/*
112
 * Calculate coupling channel and coupling coordinates.
113
 */
114
719
static void apply_channel_coupling(AC3EncodeContext *s)
115
{
116
719
    LOCAL_ALIGNED_16(CoefType, cpl_coords,      [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
117
#if CONFIG_AC3ENC_FLOAT
118
546
    LOCAL_ALIGNED_16(int32_t, fixed_cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
119
#else
120
173
    int32_t (*fixed_cpl_coords)[AC3_MAX_CHANNELS][16] = cpl_coords;
121
#endif
122
719
    int av_uninit(blk), ch, bnd, i, j;
123
719
    CoefSumType energy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][16] = {{{0}}};
124
    int cpl_start, num_cpl_coefs;
125
126
719
    memset(cpl_coords,       0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
127
#if CONFIG_AC3ENC_FLOAT
128
546
    memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
129
#endif
130
131
    /* align start to 16-byte boundary. align length to multiple of 32.
132
        note: coupling start bin % 4 will always be 1 */
133
719
    cpl_start     = s->start_freq[CPL_CH] - 1;
134
719
    num_cpl_coefs = FFALIGN(s->num_cpl_subbands * 12 + 1, 32);
135
719
    cpl_start     = FFMIN(256, cpl_start + num_cpl_coefs) - num_cpl_coefs;
136
137
    /* calculate coupling channel from fbw channels */
138
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
139
4314
        AC3Block *block = &s->blocks[blk];
140
4314
        CoefType *cpl_coef = &block->mdct_coef[CPL_CH][cpl_start];
141
4314
        if (!block->cpl_in_use)
142
            continue;
143
4314
        memset(cpl_coef, 0, num_cpl_coefs * sizeof(*cpl_coef));
144
12942
        for (ch = 1; ch <= s->fbw_channels; ch++) {
145
8628
            CoefType *ch_coef = &block->mdct_coef[ch][cpl_start];
146
8628
            if (!block->channel_in_cpl[ch])
147
                continue;
148
560820
            for (i = 0; i < num_cpl_coefs; i++)
149
552192
                cpl_coef[i] += ch_coef[i];
150
        }
151
152
        /* coefficients must be clipped in order to be encoded */
153
4314
        clip_coefficients(&s->adsp, cpl_coef, num_cpl_coefs);
154
    }
155
156
    /* calculate energy in each band in coupling channel and each fbw channel */
157
    /* TODO: possibly use SIMD to speed up energy calculation */
158
719
    bnd = 0;
159
719
    i = s->start_freq[CPL_CH];
160
3595
    while (i < s->cpl_end_freq) {
161
2876
        int band_size = s->cpl_band_sizes[bnd];
162
11504
        for (ch = CPL_CH; ch <= s->fbw_channels; ch++) {
163
60396
            for (blk = 0; blk < s->num_blocks; blk++) {
164
51768
                AC3Block *block = &s->blocks[blk];
165

51768
                if (!block->cpl_in_use || (ch > CPL_CH && !block->channel_in_cpl[ch]))
166
                    continue;
167
828288
                for (j = 0; j < band_size; j++) {
168
776520
                    CoefType v = block->mdct_coef[ch][i+j];
169
776520
                    MAC_COEF(energy[blk][ch][bnd], v, v);
170
                }
171
            }
172
        }
173
2876
        i += band_size;
174
2876
        bnd++;
175
    }
176
177
    /* calculate coupling coordinates for all blocks for all channels */
178
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
179
4314
        AC3Block *block  = &s->blocks[blk];
180
4314
        if (!block->cpl_in_use)
181
            continue;
182
12942
        for (ch = 1; ch <= s->fbw_channels; ch++) {
183
8628
            if (!block->channel_in_cpl[ch])
184
                continue;
185
43140
            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
186
34512
                cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy[blk][ch][bnd],
187
                                                          energy[blk][CPL_CH][bnd]);
188
            }
189
        }
190
    }
191
192
    /* determine which blocks to send new coupling coordinates for */
193
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
194
4314
        AC3Block *block  = &s->blocks[blk];
195
4314
        AC3Block *block0 = blk ? &s->blocks[blk-1] : NULL;
196
197
4314
        memset(block->new_cpl_coords, 0, sizeof(block->new_cpl_coords));
198
199
4314
        if (block->cpl_in_use) {
200
            /* send new coordinates if this is the first block, if previous
201
             * block did not use coupling but this block does, the channels
202
             * using coupling has changed from the previous block, or the
203
             * coordinate difference from the last block for any channel is
204
             * greater than a threshold value. */
205

4314
            if (blk == 0 || !block0->cpl_in_use) {
206
2157
                for (ch = 1; ch <= s->fbw_channels; ch++)
207
1438
                    block->new_cpl_coords[ch] = 1;
208
            } else {
209
10785
                for (ch = 1; ch <= s->fbw_channels; ch++) {
210
7190
                    if (!block->channel_in_cpl[ch])
211
                        continue;
212
7190
                    if (!block0->channel_in_cpl[ch]) {
213
                        block->new_cpl_coords[ch] = 1;
214
                    } else {
215
7190
                        CoefSumType coord_diff = 0;
216
35950
                        for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
217
28760
                            coord_diff += FFABS(cpl_coords[blk-1][ch][bnd] -
218
                                                cpl_coords[blk  ][ch][bnd]);
219
                        }
220
7190
                        coord_diff /= s->num_cpl_bands;
221
7190
                        if (coord_diff > NEW_CPL_COORD_THRESHOLD)
222
32
                            block->new_cpl_coords[ch] = 1;
223
                    }
224
                }
225
            }
226
        }
227
    }
228
229
    /* calculate final coupling coordinates, taking into account reusing of
230
       coordinates in successive blocks */
231
3595
    for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
232
2876
        blk = 0;
233
5840
        while (blk < s->num_blocks) {
234
2964
            int av_uninit(blk1);
235
2964
            AC3Block *block  = &s->blocks[blk];
236
237
2964
            if (!block->cpl_in_use) {
238
                blk++;
239
                continue;
240
            }
241
242
8892
            for (ch = 1; ch <= s->fbw_channels; ch++) {
243
                CoefSumType energy_ch, energy_cpl;
244
5928
                if (!block->channel_in_cpl[ch])
245
                    continue;
246
5928
                energy_cpl = energy[blk][CPL_CH][bnd];
247
5928
                energy_ch = energy[blk][ch][bnd];
248
5928
                blk1 = blk+1;
249

34696
                while (blk1 < s->num_blocks && !s->blocks[blk1].new_cpl_coords[ch]) {
250
28768
                    if (s->blocks[blk1].cpl_in_use) {
251
28768
                        energy_cpl += energy[blk1][CPL_CH][bnd];
252
28768
                        energy_ch += energy[blk1][ch][bnd];
253
                    }
254
28768
                    blk1++;
255
                }
256
5928
                cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
257
            }
258
2964
            blk = blk1;
259
        }
260
    }
261
262
    /* calculate exponents/mantissas for coupling coordinates */
263
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
264
4314
        AC3Block *block = &s->blocks[blk];
265
4314
        if (!block->cpl_in_use)
266
            continue;
267
268
#if CONFIG_AC3ENC_FLOAT
269
3276
        s->ac3dsp.float_to_fixed24(fixed_cpl_coords[blk][1],
270
3276
                                   cpl_coords[blk][1],
271
3276
                                   s->fbw_channels * 16);
272
#endif
273
4314
        s->ac3dsp.extract_exponents(block->cpl_coord_exp[1],
274
4314
                                    fixed_cpl_coords[blk][1],
275
4314
                                    s->fbw_channels * 16);
276
277
12942
        for (ch = 1; ch <= s->fbw_channels; ch++) {
278
            int bnd, min_exp, max_exp, master_exp;
279
280
8628
            if (!block->new_cpl_coords[ch])
281
7158
                continue;
282
283
            /* determine master exponent */
284
1470
            min_exp = max_exp = block->cpl_coord_exp[ch][0];
285
5880
            for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {
286
4410
                int exp = block->cpl_coord_exp[ch][bnd];
287
4410
                min_exp = FFMIN(exp, min_exp);
288
4410
                max_exp = FFMAX(exp, max_exp);
289
            }
290
1470
            master_exp = ((max_exp - 15) + 2) / 3;
291
1470
            master_exp = FFMAX(master_exp, 0);
292
1470
            while (min_exp < master_exp * 3)
293
                master_exp--;
294
7350
            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
295
5880
                block->cpl_coord_exp[ch][bnd] = av_clip(block->cpl_coord_exp[ch][bnd] -
296
5880
                                                        master_exp * 3, 0, 15);
297
            }
298
1470
            block->cpl_master_exp[ch] = master_exp;
299
300
            /* quantize mantissas */
301
7350
            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
302
5880
                int cpl_exp  = block->cpl_coord_exp[ch][bnd];
303
5880
                int cpl_mant = (fixed_cpl_coords[blk][ch][bnd] << (5 + cpl_exp + master_exp * 3)) >> 24;
304
5880
                if (cpl_exp == 15)
305
                    cpl_mant >>= 1;
306
                else
307
5880
                    cpl_mant -= 16;
308
309
5880
                block->cpl_coord_mant[ch][bnd] = cpl_mant;
310
            }
311
        }
312
    }
313
314
719
    if (CONFIG_EAC3_ENCODER && s->eac3)
315
273
        ff_eac3_set_cpl_states(s);
316
719
}
317
318
319
/*
320
 * Determine rematrixing flags for each block and band.
321
 */
322
1097
static void compute_rematrixing_strategy(AC3EncodeContext *s)
323
{
324
    int nb_coefs;
325
    int blk, bnd;
326
1097
    AC3Block *block, *block0 = NULL;
327
328
1097
    if (s->channel_mode != AC3_CHMODE_STEREO)
329
378
        return;
330
331
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
332
4314
        block = &s->blocks[blk];
333
4314
        block->new_rematrixing_strategy = !blk;
334
335
4314
        block->num_rematrixing_bands = 4;
336
4314
        if (block->cpl_in_use) {
337
4314
            block->num_rematrixing_bands -= (s->start_freq[CPL_CH] <= 61);
338
4314
            block->num_rematrixing_bands -= (s->start_freq[CPL_CH] == 37);
339

4314
            if (blk && block->num_rematrixing_bands != block0->num_rematrixing_bands)
340
                block->new_rematrixing_strategy = 1;
341
        }
342
4314
        nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
343
344
4314
        if (!s->rematrixing_enabled) {
345
            block0 = block;
346
            continue;
347
        }
348
349
21570
        for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
350
            /* calculate sum of squared coeffs for one band in one block */
351
17256
            int start = ff_ac3_rematrix_band_tab[bnd];
352
17256
            int end   = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
353
            CoefSumType sum[4];
354
17256
            sum_square_butterfly(s, sum, block->mdct_coef[1] + start,
355
17256
                                 block->mdct_coef[2] + start, end - start);
356
357
            /* compare sums to determine if rematrixing will be used for this band */
358

17256
            if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
359
9589
                block->rematrixing_flags[bnd] = 1;
360
            else
361
7667
                block->rematrixing_flags[bnd] = 0;
362
363
            /* determine if new rematrixing flags will be sent */
364
17256
            if (blk &&
365
14380
                block->rematrixing_flags[bnd] != block0->rematrixing_flags[bnd]) {
366
1932
                block->new_rematrixing_strategy = 1;
367
            }
368
        }
369
4314
        block0 = block;
370
    }
371
}
372
373
374
1097
int AC3_NAME(encode_frame)(AVCodecContext *avctx, AVPacket *avpkt,
375
                           const AVFrame *frame, int *got_packet_ptr)
376
{
377
1097
    AC3EncodeContext *s = avctx->priv_data;
378
    int ret;
379
380
1097
    if (s->options.allow_per_frame_metadata) {
381
        ret = ff_ac3_validate_metadata(s);
382
        if (ret)
383
            return ret;
384
    }
385
386

1097
    if (s->bit_alloc.sr_code == 1 || s->eac3)
387
1097
        ff_ac3_adjust_frame_size(s);
388
389
1097
    copy_input_samples(s, (SampleType **)frame->extended_data);
390
391
1097
    apply_mdct(s);
392
393
1097
    if (s->fixed_point)
394
551
        scale_coefficients(s);
395
396
1097
    clip_coefficients(&s->adsp, s->blocks[0].mdct_coef[1],
397
1097
                      AC3_MAX_COEFS * s->num_blocks * s->channels);
398
399
1097
    s->cpl_on = s->cpl_enabled;
400
1097
    ff_ac3_compute_coupling_strategy(s);
401
402
1097
    if (s->cpl_on)
403
719
        apply_channel_coupling(s);
404
405
1097
    compute_rematrixing_strategy(s);
406
407
1097
    if (!s->fixed_point)
408
546
        scale_coefficients(s);
409
410
1097
    ff_ac3_apply_rematrixing(s);
411
412
1097
    ff_ac3_process_exponents(s);
413
414
1097
    ret = ff_ac3_compute_bit_allocation(s);
415
1097
    if (ret) {
416
        av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
417
        return ret;
418
    }
419
420
1097
    ff_ac3_group_exponents(s);
421
422
1097
    ff_ac3_quantize_mantissas(s);
423
424
1097
    if ((ret = ff_alloc_packet2(avctx, avpkt, s->frame_size, 0)) < 0)
425
        return ret;
426
1097
    ff_ac3_output_frame(s, avpkt->data);
427
428
1097
    if (frame->pts != AV_NOPTS_VALUE)
429
1097
        avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->initial_padding);
430
431
1097
    *got_packet_ptr = 1;
432
1097
    return 0;
433
}