GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/ac3enc_template.c Lines: 176 197 89.3 %
Date: 2021-01-21 13:05:02 Branches: 115 142 81.0 %

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
#include "libavutil/mem_internal.h"
34
35
#include "audiodsp.h"
36
#include "internal.h"
37
#include "ac3enc.h"
38
#include "eac3enc.h"
39
40
41
6
static int allocate_sample_buffers(AC3EncodeContext *s)
42
{
43
    int ch;
44
45
6
    if (!FF_ALLOC_TYPED_ARRAY(s->windowed_samples, AC3_WINDOW_SIZE) ||
46
6
        !FF_ALLOCZ_TYPED_ARRAY(s->planar_samples,  s->channels))
47
        return AVERROR(ENOMEM);
48
49
15
    for (ch = 0; ch < s->channels; ch++) {
50
9
        if (!(s->planar_samples[ch] = av_mallocz((AC3_FRAME_SIZE + AC3_BLOCK_SIZE) *
51
                                                  sizeof(**s->planar_samples))))
52
            return AVERROR(ENOMEM);
53
    }
54
6
    return 0;
55
}
56
57
58
/*
59
 * Copy input samples.
60
 * Channels are reordered from FFmpeg's default order to AC-3 order.
61
 */
62
925
static void copy_input_samples(AC3EncodeContext *s, SampleType **samples)
63
{
64
    int ch;
65
66
    /* copy and remap input samples */
67
2569
    for (ch = 0; ch < s->channels; ch++) {
68
        /* copy last 256 samples of previous frame to the start of the current frame */
69
1644
        memcpy(&s->planar_samples[ch][0], &s->planar_samples[ch][AC3_BLOCK_SIZE * s->num_blocks],
70
               AC3_BLOCK_SIZE * sizeof(s->planar_samples[0][0]));
71
72
        /* copy new samples for current frame */
73
1644
        memcpy(&s->planar_samples[ch][AC3_BLOCK_SIZE],
74
1644
               samples[s->channel_map[ch]],
75
1644
               AC3_BLOCK_SIZE * s->num_blocks * sizeof(s->planar_samples[0][0]));
76
    }
77
925
}
78
79
80
/*
81
 * Apply the MDCT to input samples to generate frequency coefficients.
82
 * This applies the KBD window and normalizes the input to reduce precision
83
 * loss due to fixed-point calculations.
84
 */
85
925
static void apply_mdct(AC3EncodeContext *s)
86
{
87
    int blk, ch;
88
89
2569
    for (ch = 0; ch < s->channels; ch++) {
90
11508
        for (blk = 0; blk < s->num_blocks; blk++) {
91
9864
            AC3Block *block = &s->blocks[blk];
92
9864
            const SampleType *input_samples = &s->planar_samples[ch][blk * AC3_BLOCK_SIZE];
93
94
9864
            s->fdsp->vector_fmul(s->windowed_samples, input_samples,
95
9864
                                 s->mdct_window, AC3_BLOCK_SIZE);
96
9864
            s->fdsp->vector_fmul_reverse(s->windowed_samples + AC3_BLOCK_SIZE,
97
9864
                                         &input_samples[AC3_BLOCK_SIZE],
98
9864
                                         s->mdct_window, AC3_BLOCK_SIZE);
99
100
9864
            s->mdct.mdct_calc(&s->mdct, block->mdct_coef[ch+1],
101
9864
                              s->windowed_samples);
102
        }
103
    }
104
925
}
105
106
107
/*
108
 * Calculate coupling channel and coupling coordinates.
109
 */
110
719
static void apply_channel_coupling(AC3EncodeContext *s)
111
{
112
719
    LOCAL_ALIGNED_16(CoefType, cpl_coords,      [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
113
#if AC3ENC_FLOAT
114
546
    LOCAL_ALIGNED_16(int32_t, fixed_cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
115
#else
116
173
    int32_t (*fixed_cpl_coords)[AC3_MAX_CHANNELS][16] = cpl_coords;
117
#endif
118
719
    int av_uninit(blk), ch, bnd, i, j;
119
719
    CoefSumType energy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][16] = {{{0}}};
120
    int cpl_start, num_cpl_coefs;
121
122
719
    memset(cpl_coords,       0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
123
#if AC3ENC_FLOAT
124
546
    memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
125
#endif
126
127
    /* align start to 16-byte boundary. align length to multiple of 32.
128
        note: coupling start bin % 4 will always be 1 */
129
719
    cpl_start     = s->start_freq[CPL_CH] - 1;
130
719
    num_cpl_coefs = FFALIGN(s->num_cpl_subbands * 12 + 1, 32);
131
719
    cpl_start     = FFMIN(256, cpl_start + num_cpl_coefs) - num_cpl_coefs;
132
133
    /* calculate coupling channel from fbw channels */
134
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
135
4314
        AC3Block *block = &s->blocks[blk];
136
4314
        CoefType *cpl_coef = &block->mdct_coef[CPL_CH][cpl_start];
137
4314
        if (!block->cpl_in_use)
138
            continue;
139
4314
        memset(cpl_coef, 0, num_cpl_coefs * sizeof(*cpl_coef));
140
12942
        for (ch = 1; ch <= s->fbw_channels; ch++) {
141
8628
            CoefType *ch_coef = &block->mdct_coef[ch][cpl_start];
142
8628
            if (!block->channel_in_cpl[ch])
143
                continue;
144
560820
            for (i = 0; i < num_cpl_coefs; i++)
145
552192
                cpl_coef[i] += ch_coef[i];
146
        }
147
148
        /* coefficients must be clipped in order to be encoded */
149
4314
        clip_coefficients(&s->adsp, cpl_coef, num_cpl_coefs);
150
    }
151
152
    /* calculate energy in each band in coupling channel and each fbw channel */
153
    /* TODO: possibly use SIMD to speed up energy calculation */
154
719
    bnd = 0;
155
719
    i = s->start_freq[CPL_CH];
156
3595
    while (i < s->cpl_end_freq) {
157
2876
        int band_size = s->cpl_band_sizes[bnd];
158
11504
        for (ch = CPL_CH; ch <= s->fbw_channels; ch++) {
159
60396
            for (blk = 0; blk < s->num_blocks; blk++) {
160
51768
                AC3Block *block = &s->blocks[blk];
161

51768
                if (!block->cpl_in_use || (ch > CPL_CH && !block->channel_in_cpl[ch]))
162
                    continue;
163
828288
                for (j = 0; j < band_size; j++) {
164
776520
                    CoefType v = block->mdct_coef[ch][i+j];
165
776520
                    MAC_COEF(energy[blk][ch][bnd], v, v);
166
                }
167
            }
168
        }
169
2876
        i += band_size;
170
2876
        bnd++;
171
    }
172
173
    /* calculate coupling coordinates for all blocks for all channels */
174
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
175
4314
        AC3Block *block  = &s->blocks[blk];
176
4314
        if (!block->cpl_in_use)
177
            continue;
178
12942
        for (ch = 1; ch <= s->fbw_channels; ch++) {
179
8628
            if (!block->channel_in_cpl[ch])
180
                continue;
181
43140
            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
182
34512
                cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy[blk][ch][bnd],
183
                                                          energy[blk][CPL_CH][bnd]);
184
            }
185
        }
186
    }
187
188
    /* determine which blocks to send new coupling coordinates for */
189
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
190
4314
        AC3Block *block  = &s->blocks[blk];
191
4314
        AC3Block *block0 = blk ? &s->blocks[blk-1] : NULL;
192
193
4314
        memset(block->new_cpl_coords, 0, sizeof(block->new_cpl_coords));
194
195
4314
        if (block->cpl_in_use) {
196
            /* send new coordinates if this is the first block, if previous
197
             * block did not use coupling but this block does, the channels
198
             * using coupling has changed from the previous block, or the
199
             * coordinate difference from the last block for any channel is
200
             * greater than a threshold value. */
201

4314
            if (blk == 0 || !block0->cpl_in_use) {
202
2157
                for (ch = 1; ch <= s->fbw_channels; ch++)
203
1438
                    block->new_cpl_coords[ch] = 1;
204
            } else {
205
10785
                for (ch = 1; ch <= s->fbw_channels; ch++) {
206
7190
                    if (!block->channel_in_cpl[ch])
207
                        continue;
208
7190
                    if (!block0->channel_in_cpl[ch]) {
209
                        block->new_cpl_coords[ch] = 1;
210
                    } else {
211
7190
                        CoefSumType coord_diff = 0;
212
35950
                        for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
213
28760
                            coord_diff += FFABS(cpl_coords[blk-1][ch][bnd] -
214
                                                cpl_coords[blk  ][ch][bnd]);
215
                        }
216
7190
                        coord_diff /= s->num_cpl_bands;
217
7190
                        if (coord_diff > NEW_CPL_COORD_THRESHOLD)
218
32
                            block->new_cpl_coords[ch] = 1;
219
                    }
220
                }
221
            }
222
        }
223
    }
224
225
    /* calculate final coupling coordinates, taking into account reusing of
226
       coordinates in successive blocks */
227
3595
    for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
228
2876
        blk = 0;
229
5840
        while (blk < s->num_blocks) {
230
2964
            int av_uninit(blk1);
231
2964
            AC3Block *block  = &s->blocks[blk];
232
233
2964
            if (!block->cpl_in_use) {
234
                blk++;
235
                continue;
236
            }
237
238
8892
            for (ch = 1; ch <= s->fbw_channels; ch++) {
239
                CoefSumType energy_ch, energy_cpl;
240
5928
                if (!block->channel_in_cpl[ch])
241
                    continue;
242
5928
                energy_cpl = energy[blk][CPL_CH][bnd];
243
5928
                energy_ch = energy[blk][ch][bnd];
244
5928
                blk1 = blk+1;
245

34696
                while (blk1 < s->num_blocks && !s->blocks[blk1].new_cpl_coords[ch]) {
246
28768
                    if (s->blocks[blk1].cpl_in_use) {
247
28768
                        energy_cpl += energy[blk1][CPL_CH][bnd];
248
28768
                        energy_ch += energy[blk1][ch][bnd];
249
                    }
250
28768
                    blk1++;
251
                }
252
5928
                cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
253
            }
254
2964
            blk = blk1;
255
        }
256
    }
257
258
    /* calculate exponents/mantissas for coupling coordinates */
259
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
260
4314
        AC3Block *block = &s->blocks[blk];
261
4314
        if (!block->cpl_in_use)
262
            continue;
263
264
#if AC3ENC_FLOAT
265
3276
        s->ac3dsp.float_to_fixed24(fixed_cpl_coords[blk][1],
266
3276
                                   cpl_coords[blk][1],
267
3276
                                   s->fbw_channels * 16);
268
#endif
269
4314
        s->ac3dsp.extract_exponents(block->cpl_coord_exp[1],
270
4314
                                    fixed_cpl_coords[blk][1],
271
4314
                                    s->fbw_channels * 16);
272
273
12942
        for (ch = 1; ch <= s->fbw_channels; ch++) {
274
            int bnd, min_exp, max_exp, master_exp;
275
276
8628
            if (!block->new_cpl_coords[ch])
277
7158
                continue;
278
279
            /* determine master exponent */
280
1470
            min_exp = max_exp = block->cpl_coord_exp[ch][0];
281
5880
            for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {
282
4410
                int exp = block->cpl_coord_exp[ch][bnd];
283
4410
                min_exp = FFMIN(exp, min_exp);
284
4410
                max_exp = FFMAX(exp, max_exp);
285
            }
286
1470
            master_exp = ((max_exp - 15) + 2) / 3;
287
1470
            master_exp = FFMAX(master_exp, 0);
288
1470
            while (min_exp < master_exp * 3)
289
                master_exp--;
290
7350
            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
291
5880
                block->cpl_coord_exp[ch][bnd] = av_clip(block->cpl_coord_exp[ch][bnd] -
292
5880
                                                        master_exp * 3, 0, 15);
293
            }
294
1470
            block->cpl_master_exp[ch] = master_exp;
295
296
            /* quantize mantissas */
297
7350
            for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
298
5880
                int cpl_exp  = block->cpl_coord_exp[ch][bnd];
299
5880
                int cpl_mant = (fixed_cpl_coords[blk][ch][bnd] << (5 + cpl_exp + master_exp * 3)) >> 24;
300
5880
                if (cpl_exp == 15)
301
                    cpl_mant >>= 1;
302
                else
303
5880
                    cpl_mant -= 16;
304
305
5880
                block->cpl_coord_mant[ch][bnd] = cpl_mant;
306
            }
307
        }
308
    }
309
310
546
    if (AC3ENC_FLOAT && CONFIG_EAC3_ENCODER && s->eac3)
311
273
        ff_eac3_set_cpl_states(s);
312
719
}
313
314
315
/*
316
 * Determine rematrixing flags for each block and band.
317
 */
318
925
static void compute_rematrixing_strategy(AC3EncodeContext *s)
319
{
320
    int nb_coefs;
321
    int blk, bnd;
322
925
    AC3Block *block, *block0 = NULL;
323
324
925
    if (s->channel_mode != AC3_CHMODE_STEREO)
325
206
        return;
326
327
5033
    for (blk = 0; blk < s->num_blocks; blk++) {
328
4314
        block = &s->blocks[blk];
329
4314
        block->new_rematrixing_strategy = !blk;
330
331
4314
        block->num_rematrixing_bands = 4;
332
4314
        if (block->cpl_in_use) {
333
4314
            block->num_rematrixing_bands -= (s->start_freq[CPL_CH] <= 61);
334
4314
            block->num_rematrixing_bands -= (s->start_freq[CPL_CH] == 37);
335

4314
            if (blk && block->num_rematrixing_bands != block0->num_rematrixing_bands)
336
                block->new_rematrixing_strategy = 1;
337
        }
338
4314
        nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
339
340
4314
        if (!s->rematrixing_enabled) {
341
            block0 = block;
342
            continue;
343
        }
344
345
21570
        for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
346
            /* calculate sum of squared coeffs for one band in one block */
347
17256
            int start = ff_ac3_rematrix_band_tab[bnd];
348
17256
            int end   = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
349
            CoefSumType sum[4];
350
17256
            sum_square_butterfly(s, sum, block->mdct_coef[1] + start,
351
17256
                                 block->mdct_coef[2] + start, end - start);
352
353
            /* compare sums to determine if rematrixing will be used for this band */
354

17256
            if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
355
9547
                block->rematrixing_flags[bnd] = 1;
356
            else
357
7709
                block->rematrixing_flags[bnd] = 0;
358
359
            /* determine if new rematrixing flags will be sent */
360
17256
            if (blk &&
361
14380
                block->rematrixing_flags[bnd] != block0->rematrixing_flags[bnd]) {
362
1886
                block->new_rematrixing_strategy = 1;
363
            }
364
        }
365
4314
        block0 = block;
366
    }
367
}
368
369
370
925
int AC3_NAME(encode_frame)(AVCodecContext *avctx, AVPacket *avpkt,
371
                           const AVFrame *frame, int *got_packet_ptr)
372
{
373
925
    AC3EncodeContext *s = avctx->priv_data;
374
    int ret;
375
376
925
    if (s->options.allow_per_frame_metadata) {
377
        ret = ff_ac3_validate_metadata(s);
378
        if (ret)
379
            return ret;
380
    }
381
382

925
    if (s->bit_alloc.sr_code == 1 || (AC3ENC_FLOAT && s->eac3))
383
925
        ff_ac3_adjust_frame_size(s);
384
385
925
    copy_input_samples(s, (SampleType **)frame->extended_data);
386
387
925
    apply_mdct(s);
388
389
925
    s->cpl_on = s->cpl_enabled;
390
925
    ff_ac3_compute_coupling_strategy(s);
391
392
925
    if (s->cpl_on)
393
719
        apply_channel_coupling(s);
394
395
925
    compute_rematrixing_strategy(s);
396
397
#if AC3ENC_FLOAT
398
546
    scale_coefficients(s);
399
#endif
400
401
925
    return ff_ac3_encode_frame_common_end(avctx, avpkt, frame, got_packet_ptr);
402
}