GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/aacpsy.c Lines: 367 449 81.7 %
Date: 2019-11-22 03:34:36 Branches: 260 341 76.2 %

Line Branch Exec Source
1
/*
2
 * AAC encoder psychoacoustic model
3
 * Copyright (C) 2008 Konstantin Shishkov
4
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
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 * FFmpeg is distributed in the hope that it will be useful,
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
16
 *
17
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21
22
/**
23
 * @file
24
 * AAC encoder psychoacoustic model
25
 */
26
27
#include "libavutil/attributes.h"
28
#include "libavutil/ffmath.h"
29
30
#include "avcodec.h"
31
#include "aactab.h"
32
#include "psymodel.h"
33
34
/***********************************
35
 *              TODOs:
36
 * try other bitrate controlling mechanism (maybe use ratecontrol.c?)
37
 * control quality for quality-based output
38
 **********************************/
39
40
/**
41
 * constants for 3GPP AAC psychoacoustic model
42
 * @{
43
 */
44
#define PSY_3GPP_THR_SPREAD_HI   1.5f // spreading factor for low-to-hi threshold spreading  (15 dB/Bark)
45
#define PSY_3GPP_THR_SPREAD_LOW  3.0f // spreading factor for hi-to-low threshold spreading  (30 dB/Bark)
46
/* spreading factor for low-to-hi energy spreading, long block, > 22kbps/channel (20dB/Bark) */
47
#define PSY_3GPP_EN_SPREAD_HI_L1 2.0f
48
/* spreading factor for low-to-hi energy spreading, long block, <= 22kbps/channel (15dB/Bark) */
49
#define PSY_3GPP_EN_SPREAD_HI_L2 1.5f
50
/* spreading factor for low-to-hi energy spreading, short block (15 dB/Bark) */
51
#define PSY_3GPP_EN_SPREAD_HI_S  1.5f
52
/* spreading factor for hi-to-low energy spreading, long block (30dB/Bark) */
53
#define PSY_3GPP_EN_SPREAD_LOW_L 3.0f
54
/* spreading factor for hi-to-low energy spreading, short block (20dB/Bark) */
55
#define PSY_3GPP_EN_SPREAD_LOW_S 2.0f
56
57
#define PSY_3GPP_RPEMIN      0.01f
58
#define PSY_3GPP_RPELEV      2.0f
59
60
#define PSY_3GPP_C1          3.0f           /* log2(8) */
61
#define PSY_3GPP_C2          1.3219281f     /* log2(2.5) */
62
#define PSY_3GPP_C3          0.55935729f    /* 1 - C2 / C1 */
63
64
#define PSY_SNR_1DB          7.9432821e-1f  /* -1dB */
65
#define PSY_SNR_25DB         3.1622776e-3f  /* -25dB */
66
67
#define PSY_3GPP_SAVE_SLOPE_L  -0.46666667f
68
#define PSY_3GPP_SAVE_SLOPE_S  -0.36363637f
69
#define PSY_3GPP_SAVE_ADD_L    -0.84285712f
70
#define PSY_3GPP_SAVE_ADD_S    -0.75f
71
#define PSY_3GPP_SPEND_SLOPE_L  0.66666669f
72
#define PSY_3GPP_SPEND_SLOPE_S  0.81818181f
73
#define PSY_3GPP_SPEND_ADD_L   -0.35f
74
#define PSY_3GPP_SPEND_ADD_S   -0.26111111f
75
#define PSY_3GPP_CLIP_LO_L      0.2f
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#define PSY_3GPP_CLIP_LO_S      0.2f
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#define PSY_3GPP_CLIP_HI_L      0.95f
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#define PSY_3GPP_CLIP_HI_S      0.75f
79
80
#define PSY_3GPP_AH_THR_LONG    0.5f
81
#define PSY_3GPP_AH_THR_SHORT   0.63f
82
83
#define PSY_PE_FORGET_SLOPE  511
84
85
enum {
86
    PSY_3GPP_AH_NONE,
87
    PSY_3GPP_AH_INACTIVE,
88
    PSY_3GPP_AH_ACTIVE
89
};
90
91
#define PSY_3GPP_BITS_TO_PE(bits) ((bits) * 1.18f)
92
#define PSY_3GPP_PE_TO_BITS(bits) ((bits) / 1.18f)
93
94
/* LAME psy model constants */
95
#define PSY_LAME_FIR_LEN 21         ///< LAME psy model FIR order
96
#define AAC_BLOCK_SIZE_LONG 1024    ///< long block size
97
#define AAC_BLOCK_SIZE_SHORT 128    ///< short block size
98
#define AAC_NUM_BLOCKS_SHORT 8      ///< number of blocks in a short sequence
99
#define PSY_LAME_NUM_SUBBLOCKS 3    ///< Number of sub-blocks in each short block
100
101
/**
102
 * @}
103
 */
104
105
/**
106
 * information for single band used by 3GPP TS26.403-inspired psychoacoustic model
107
 */
108
typedef struct AacPsyBand{
109
    float energy;       ///< band energy
110
    float thr;          ///< energy threshold
111
    float thr_quiet;    ///< threshold in quiet
112
    float nz_lines;     ///< number of non-zero spectral lines
113
    float active_lines; ///< number of active spectral lines
114
    float pe;           ///< perceptual entropy
115
    float pe_const;     ///< constant part of the PE calculation
116
    float norm_fac;     ///< normalization factor for linearization
117
    int   avoid_holes;  ///< hole avoidance flag
118
}AacPsyBand;
119
120
/**
121
 * single/pair channel context for psychoacoustic model
122
 */
123
typedef struct AacPsyChannel{
124
    AacPsyBand band[128];               ///< bands information
125
    AacPsyBand prev_band[128];          ///< bands information from the previous frame
126
127
    float       win_energy;              ///< sliding average of channel energy
128
    float       iir_state[2];            ///< hi-pass IIR filter state
129
    uint8_t     next_grouping;           ///< stored grouping scheme for the next frame (in case of 8 short window sequence)
130
    enum WindowSequence next_window_seq; ///< window sequence to be used in the next frame
131
    /* LAME psy model specific members */
132
    float attack_threshold;              ///< attack threshold for this channel
133
    float prev_energy_subshort[AAC_NUM_BLOCKS_SHORT * PSY_LAME_NUM_SUBBLOCKS];
134
    int   prev_attack;                   ///< attack value for the last short block in the previous sequence
135
}AacPsyChannel;
136
137
/**
138
 * psychoacoustic model frame type-dependent coefficients
139
 */
140
typedef struct AacPsyCoeffs{
141
    float ath;           ///< absolute threshold of hearing per bands
142
    float barks;         ///< Bark value for each spectral band in long frame
143
    float spread_low[2]; ///< spreading factor for low-to-high threshold spreading in long frame
144
    float spread_hi [2]; ///< spreading factor for high-to-low threshold spreading in long frame
145
    float min_snr;       ///< minimal SNR
146
}AacPsyCoeffs;
147
148
/**
149
 * 3GPP TS26.403-inspired psychoacoustic model specific data
150
 */
151
typedef struct AacPsyContext{
152
    int chan_bitrate;     ///< bitrate per channel
153
    int frame_bits;       ///< average bits per frame
154
    int fill_level;       ///< bit reservoir fill level
155
    struct {
156
        float min;        ///< minimum allowed PE for bit factor calculation
157
        float max;        ///< maximum allowed PE for bit factor calculation
158
        float previous;   ///< allowed PE of the previous frame
159
        float correction; ///< PE correction factor
160
    } pe;
161
    AacPsyCoeffs psy_coef[2][64];
162
    AacPsyChannel *ch;
163
    float global_quality; ///< normalized global quality taken from avctx
164
}AacPsyContext;
165
166
/**
167
 * LAME psy model preset struct
168
 */
169
typedef struct PsyLamePreset {
170
    int   quality;  ///< Quality to map the rest of the vaules to.
171
     /* This is overloaded to be both kbps per channel in ABR mode, and
172
      * requested quality in constant quality mode.
173
      */
174
    float st_lrm;   ///< short threshold for L, R, and M channels
175
} PsyLamePreset;
176
177
/**
178
 * LAME psy model preset table for ABR
179
 */
180
static const PsyLamePreset psy_abr_map[] = {
181
/* TODO: Tuning. These were taken from LAME. */
182
/* kbps/ch st_lrm   */
183
    {  8,  6.60},
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    { 16,  6.60},
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    { 24,  6.60},
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    { 32,  6.60},
187
    { 40,  6.60},
188
    { 48,  6.60},
189
    { 56,  6.60},
190
    { 64,  6.40},
191
    { 80,  6.00},
192
    { 96,  5.60},
193
    {112,  5.20},
194
    {128,  5.20},
195
    {160,  5.20}
196
};
197
198
/**
199
* LAME psy model preset table for constant quality
200
*/
201
static const PsyLamePreset psy_vbr_map[] = {
202
/* vbr_q  st_lrm    */
203
    { 0,  4.20},
204
    { 1,  4.20},
205
    { 2,  4.20},
206
    { 3,  4.20},
207
    { 4,  4.20},
208
    { 5,  4.20},
209
    { 6,  4.20},
210
    { 7,  4.20},
211
    { 8,  4.20},
212
    { 9,  4.20},
213
    {10,  4.20}
214
};
215
216
/**
217
 * LAME psy model FIR coefficient table
218
 */
219
static const float psy_fir_coeffs[] = {
220
    -8.65163e-18 * 2, -0.00851586 * 2, -6.74764e-18 * 2, 0.0209036 * 2,
221
    -3.36639e-17 * 2, -0.0438162 * 2,  -1.54175e-17 * 2, 0.0931738 * 2,
222
    -5.52212e-17 * 2, -0.313819 * 2
223
};
224
225
#if ARCH_MIPS
226
#   include "mips/aacpsy_mips.h"
227
#endif /* ARCH_MIPS */
228
229
/**
230
 * Calculate the ABR attack threshold from the above LAME psymodel table.
231
 */
232
25
static float lame_calc_attack_threshold(int bitrate)
233
{
234
    /* Assume max bitrate to start with */
235
25
    int lower_range = 12, upper_range = 12;
236
25
    int lower_range_kbps = psy_abr_map[12].quality;
237
25
    int upper_range_kbps = psy_abr_map[12].quality;
238
    int i;
239
240
    /* Determine which bitrates the value specified falls between.
241
     * If the loop ends without breaking our above assumption of 320kbps was correct.
242
     */
243
214
    for (i = 1; i < 13; i++) {
244
210
        if (FFMAX(bitrate, psy_abr_map[i].quality) != bitrate) {
245
21
            upper_range = i;
246
21
            upper_range_kbps = psy_abr_map[i    ].quality;
247
21
            lower_range = i - 1;
248
21
            lower_range_kbps = psy_abr_map[i - 1].quality;
249
21
            break; /* Upper range found */
250
        }
251
    }
252
253
    /* Determine which range the value specified is closer to */
254
25
    if ((upper_range_kbps - bitrate) > (bitrate - lower_range_kbps))
255
21
        return psy_abr_map[lower_range].st_lrm;
256
4
    return psy_abr_map[upper_range].st_lrm;
257
}
258
259
/**
260
 * LAME psy model specific initialization
261
 */
262
11
static av_cold void lame_window_init(AacPsyContext *ctx, AVCodecContext *avctx)
263
{
264
    int i, j;
265
266
36
    for (i = 0; i < avctx->channels; i++) {
267
25
        AacPsyChannel *pch = &ctx->ch[i];
268
269
25
        if (avctx->flags & AV_CODEC_FLAG_QSCALE)
270
            pch->attack_threshold = psy_vbr_map[avctx->global_quality / FF_QP2LAMBDA].st_lrm;
271
        else
272
25
            pch->attack_threshold = lame_calc_attack_threshold(avctx->bit_rate / avctx->channels / 1000);
273
274
625
        for (j = 0; j < AAC_NUM_BLOCKS_SHORT * PSY_LAME_NUM_SUBBLOCKS; j++)
275
600
            pch->prev_energy_subshort[j] = 10.0f;
276
    }
277
11
}
278
279
/**
280
 * Calculate Bark value for given line.
281
 */
282
704
static av_cold float calc_bark(float f)
283
{
284
704
    return 13.3f * atanf(0.00076f * f) + 3.5f * atanf((f / 7500.0f) * (f / 7500.0f));
285
}
286
287
#define ATH_ADD 4
288
/**
289
 * Calculate ATH value for given frequency.
290
 * Borrowed from Lame.
291
 */
292
14341
static av_cold float ath(float f, float add)
293
{
294
14341
    f /= 1000.0f;
295
14341
    return    3.64 * pow(f, -0.8)
296
14341
            - 6.8  * exp(-0.6  * (f - 3.4) * (f - 3.4))
297
14341
            + 6.0  * exp(-0.15 * (f - 8.7) * (f - 8.7))
298
14341
            + (0.6 + 0.04 * add) * 0.001 * f * f * f * f;
299
}
300
301
11
static av_cold int psy_3gpp_init(FFPsyContext *ctx) {
302
    AacPsyContext *pctx;
303
    float bark;
304
    int i, j, g, start;
305
    float prev, minscale, minath, minsnr, pe_min;
306
11
    int chan_bitrate = ctx->avctx->bit_rate / ((ctx->avctx->flags & AV_CODEC_FLAG_QSCALE) ? 2.0f : ctx->avctx->channels);
307
308


11
    const int bandwidth    = ctx->cutoff ? ctx->cutoff : AAC_CUTOFF(ctx->avctx);
309
11
    const float num_bark   = calc_bark((float)bandwidth);
310
311
11
    ctx->model_priv_data = av_mallocz(sizeof(AacPsyContext));
312
11
    if (!ctx->model_priv_data)
313
        return AVERROR(ENOMEM);
314
11
    pctx = ctx->model_priv_data;
315
11
    pctx->global_quality = (ctx->avctx->global_quality ? ctx->avctx->global_quality : 120) * 0.01f;
316
317
11
    if (ctx->avctx->flags & AV_CODEC_FLAG_QSCALE) {
318
        /* Use the target average bitrate to compute spread parameters */
319
        chan_bitrate = (int)(chan_bitrate / 120.0 * (ctx->avctx->global_quality ? ctx->avctx->global_quality : 120));
320
    }
321
322
11
    pctx->chan_bitrate = chan_bitrate;
323
11
    pctx->frame_bits   = FFMIN(2560, chan_bitrate * AAC_BLOCK_SIZE_LONG / ctx->avctx->sample_rate);
324
11
    pctx->pe.min       =  8.0f * AAC_BLOCK_SIZE_LONG * bandwidth / (ctx->avctx->sample_rate * 2.0f);
325
11
    pctx->pe.max       = 12.0f * AAC_BLOCK_SIZE_LONG * bandwidth / (ctx->avctx->sample_rate * 2.0f);
326
11
    ctx->bitres.size   = 6144 - pctx->frame_bits;
327
11
    ctx->bitres.size  -= ctx->bitres.size % 8;
328
11
    pctx->fill_level   = ctx->bitres.size;
329
11
    minath = ath(3410 - 0.733 * ATH_ADD, ATH_ADD);
330
33
    for (j = 0; j < 2; j++) {
331
22
        AacPsyCoeffs *coeffs = pctx->psy_coef[j];
332
22
        const uint8_t *band_sizes = ctx->bands[j];
333
22
        float line_to_frequency = ctx->avctx->sample_rate / (j ? 256.f : 2048.0f);
334
22
        float avg_chan_bits = chan_bitrate * (j ? 128.0f : 1024.0f) / ctx->avctx->sample_rate;
335
        /* reference encoder uses 2.4% here instead of 60% like the spec says */
336
22
        float bark_pe = 0.024f * PSY_3GPP_BITS_TO_PE(avg_chan_bits) / num_bark;
337
22
        float en_spread_low = j ? PSY_3GPP_EN_SPREAD_LOW_S : PSY_3GPP_EN_SPREAD_LOW_L;
338
        /* High energy spreading for long blocks <= 22kbps/channel and short blocks are the same. */
339

22
        float en_spread_hi  = (j || (chan_bitrate <= 22.0f)) ? PSY_3GPP_EN_SPREAD_HI_S : PSY_3GPP_EN_SPREAD_HI_L1;
340
341
22
        i = 0;
342
22
        prev = 0.0;
343
715
        for (g = 0; g < ctx->num_bands[j]; g++) {
344
693
            i += band_sizes[g];
345
693
            bark = calc_bark((i-1) * line_to_frequency);
346
693
            coeffs[g].barks = (bark + prev) / 2.0;
347
693
            prev = bark;
348
        }
349
693
        for (g = 0; g < ctx->num_bands[j] - 1; g++) {
350
671
            AacPsyCoeffs *coeff = &coeffs[g];
351
671
            float bark_width = coeffs[g+1].barks - coeffs->barks;
352
671
            coeff->spread_low[0] = ff_exp10(-bark_width * PSY_3GPP_THR_SPREAD_LOW);
353
671
            coeff->spread_hi [0] = ff_exp10(-bark_width * PSY_3GPP_THR_SPREAD_HI);
354
671
            coeff->spread_low[1] = ff_exp10(-bark_width * en_spread_low);
355
671
            coeff->spread_hi [1] = ff_exp10(-bark_width * en_spread_hi);
356
671
            pe_min = bark_pe * bark_width;
357
671
            minsnr = exp2(pe_min / band_sizes[g]) - 1.5f;
358
671
            coeff->min_snr = av_clipf(1.0f / minsnr, PSY_SNR_25DB, PSY_SNR_1DB);
359
        }
360
22
        start = 0;
361
715
        for (g = 0; g < ctx->num_bands[j]; g++) {
362
693
            minscale = ath(start * line_to_frequency, ATH_ADD);
363
12672
            for (i = 1; i < band_sizes[g]; i++)
364
11979
                minscale = FFMIN(minscale, ath((start + i) * line_to_frequency, ATH_ADD));
365
693
            coeffs[g].ath = minscale - minath;
366
693
            start += band_sizes[g];
367
        }
368
    }
369
370
11
    pctx->ch = av_mallocz_array(ctx->avctx->channels, sizeof(AacPsyChannel));
371
11
    if (!pctx->ch) {
372
        av_freep(&ctx->model_priv_data);
373
        return AVERROR(ENOMEM);
374
    }
375
376
11
    lame_window_init(pctx, ctx->avctx);
377
378
11
    return 0;
379
}
380
381
/**
382
 * IIR filter used in block switching decision
383
 */
384
static float iir_filter(int in, float state[2])
385
{
386
    float ret;
387
388
    ret = 0.7548f * (in - state[0]) + 0.5095f * state[1];
389
    state[0] = in;
390
    state[1] = ret;
391
    return ret;
392
}
393
394
/**
395
 * window grouping information stored as bits (0 - new group, 1 - group continues)
396
 */
397
static const uint8_t window_grouping[9] = {
398
    0xB6, 0x6C, 0xD8, 0xB2, 0x66, 0xC6, 0x96, 0x36, 0x36
399
};
400
401
/**
402
 * Tell encoder which window types to use.
403
 * @see 3GPP TS26.403 5.4.1 "Blockswitching"
404
 */
405
static av_unused FFPsyWindowInfo psy_3gpp_window(FFPsyContext *ctx,
406
                                                 const int16_t *audio,
407
                                                 const int16_t *la,
408
                                                 int channel, int prev_type)
409
{
410
    int i, j;
411
    int br               = ((AacPsyContext*)ctx->model_priv_data)->chan_bitrate;
412
    int attack_ratio     = br <= 16000 ? 18 : 10;
413
    AacPsyContext *pctx = (AacPsyContext*) ctx->model_priv_data;
414
    AacPsyChannel *pch  = &pctx->ch[channel];
415
    uint8_t grouping     = 0;
416
    int next_type        = pch->next_window_seq;
417
    FFPsyWindowInfo wi  = { { 0 } };
418
419
    if (la) {
420
        float s[8], v;
421
        int switch_to_eight = 0;
422
        float sum = 0.0, sum2 = 0.0;
423
        int attack_n = 0;
424
        int stay_short = 0;
425
        for (i = 0; i < 8; i++) {
426
            for (j = 0; j < 128; j++) {
427
                v = iir_filter(la[i*128+j], pch->iir_state);
428
                sum += v*v;
429
            }
430
            s[i]  = sum;
431
            sum2 += sum;
432
        }
433
        for (i = 0; i < 8; i++) {
434
            if (s[i] > pch->win_energy * attack_ratio) {
435
                attack_n        = i + 1;
436
                switch_to_eight = 1;
437
                break;
438
            }
439
        }
440
        pch->win_energy = pch->win_energy*7/8 + sum2/64;
441
442
        wi.window_type[1] = prev_type;
443
        switch (prev_type) {
444
        case ONLY_LONG_SEQUENCE:
445
            wi.window_type[0] = switch_to_eight ? LONG_START_SEQUENCE : ONLY_LONG_SEQUENCE;
446
            next_type = switch_to_eight ? EIGHT_SHORT_SEQUENCE : ONLY_LONG_SEQUENCE;
447
            break;
448
        case LONG_START_SEQUENCE:
449
            wi.window_type[0] = EIGHT_SHORT_SEQUENCE;
450
            grouping = pch->next_grouping;
451
            next_type = switch_to_eight ? EIGHT_SHORT_SEQUENCE : LONG_STOP_SEQUENCE;
452
            break;
453
        case LONG_STOP_SEQUENCE:
454
            wi.window_type[0] = switch_to_eight ? LONG_START_SEQUENCE : ONLY_LONG_SEQUENCE;
455
            next_type = switch_to_eight ? EIGHT_SHORT_SEQUENCE : ONLY_LONG_SEQUENCE;
456
            break;
457
        case EIGHT_SHORT_SEQUENCE:
458
            stay_short = next_type == EIGHT_SHORT_SEQUENCE || switch_to_eight;
459
            wi.window_type[0] = stay_short ? EIGHT_SHORT_SEQUENCE : LONG_STOP_SEQUENCE;
460
            grouping = next_type == EIGHT_SHORT_SEQUENCE ? pch->next_grouping : 0;
461
            next_type = switch_to_eight ? EIGHT_SHORT_SEQUENCE : LONG_STOP_SEQUENCE;
462
            break;
463
        }
464
465
        pch->next_grouping = window_grouping[attack_n];
466
        pch->next_window_seq = next_type;
467
    } else {
468
        for (i = 0; i < 3; i++)
469
            wi.window_type[i] = prev_type;
470
        grouping = (prev_type == EIGHT_SHORT_SEQUENCE) ? window_grouping[0] : 0;
471
    }
472
473
    wi.window_shape   = 1;
474
    if (wi.window_type[0] != EIGHT_SHORT_SEQUENCE) {
475
        wi.num_windows = 1;
476
        wi.grouping[0] = 1;
477
    } else {
478
        int lastgrp = 0;
479
        wi.num_windows = 8;
480
        for (i = 0; i < 8; i++) {
481
            if (!((grouping >> i) & 1))
482
                lastgrp = i;
483
            wi.grouping[lastgrp]++;
484
        }
485
    }
486
487
    return wi;
488
}
489
490
/* 5.6.1.2 "Calculation of Bit Demand" */
491
11739
static int calc_bit_demand(AacPsyContext *ctx, float pe, int bits, int size,
492
                           int short_window)
493
{
494
11739
    const float bitsave_slope  = short_window ? PSY_3GPP_SAVE_SLOPE_S  : PSY_3GPP_SAVE_SLOPE_L;
495
11739
    const float bitsave_add    = short_window ? PSY_3GPP_SAVE_ADD_S    : PSY_3GPP_SAVE_ADD_L;
496
11739
    const float bitspend_slope = short_window ? PSY_3GPP_SPEND_SLOPE_S : PSY_3GPP_SPEND_SLOPE_L;
497
11739
    const float bitspend_add   = short_window ? PSY_3GPP_SPEND_ADD_S   : PSY_3GPP_SPEND_ADD_L;
498
11739
    const float clip_low       = short_window ? PSY_3GPP_CLIP_LO_S     : PSY_3GPP_CLIP_LO_L;
499
11739
    const float clip_high      = short_window ? PSY_3GPP_CLIP_HI_S     : PSY_3GPP_CLIP_HI_L;
500
    float clipped_pe, bit_save, bit_spend, bit_factor, fill_level, forgetful_min_pe;
501
502
11739
    ctx->fill_level += ctx->frame_bits - bits;
503
11739
    ctx->fill_level  = av_clip(ctx->fill_level, 0, size);
504
11739
    fill_level = av_clipf((float)ctx->fill_level / size, clip_low, clip_high);
505
11739
    clipped_pe = av_clipf(pe, ctx->pe.min, ctx->pe.max);
506
11739
    bit_save   = (fill_level + bitsave_add) * bitsave_slope;
507
    assert(bit_save <= 0.3f && bit_save >= -0.05000001f);
508
11739
    bit_spend  = (fill_level + bitspend_add) * bitspend_slope;
509
    assert(bit_spend <= 0.5f && bit_spend >= -0.1f);
510
    /* The bit factor graph in the spec is obviously incorrect.
511
     *      bit_spend + ((bit_spend - bit_spend))...
512
     * The reference encoder subtracts everything from 1, but also seems incorrect.
513
     *      1 - bit_save + ((bit_spend + bit_save))...
514
     * Hopefully below is correct.
515
     */
516
11739
    bit_factor = 1.0f - bit_save + ((bit_spend - bit_save) / (ctx->pe.max - ctx->pe.min)) * (clipped_pe - ctx->pe.min);
517
    /* NOTE: The reference encoder attempts to center pe max/min around the current pe.
518
     * Here we do that by slowly forgetting pe.min when pe stays in a range that makes
519
     * it unlikely (ie: above the mean)
520
     */
521
11739
    ctx->pe.max = FFMAX(pe, ctx->pe.max);
522
23478
    forgetful_min_pe = ((ctx->pe.min * PSY_PE_FORGET_SLOPE)
523
11739
        + FFMAX(ctx->pe.min, pe * (pe / ctx->pe.max))) / (PSY_PE_FORGET_SLOPE + 1);
524
11739
    ctx->pe.min = FFMIN(pe, forgetful_min_pe);
525
526
    /* NOTE: allocate a minimum of 1/8th average frame bits, to avoid
527
     *   reservoir starvation from producing zero-bit frames
528
     */
529

11739
    return FFMIN(
530
        ctx->frame_bits * bit_factor,
531
        FFMAX(ctx->frame_bits + size - bits, ctx->frame_bits / 8));
532
}
533
534
1978697
static float calc_pe_3gpp(AacPsyBand *band)
535
{
536
    float pe, a;
537
538
1978697
    band->pe           = 0.0f;
539
1978697
    band->pe_const     = 0.0f;
540
1978697
    band->active_lines = 0.0f;
541
1978697
    if (band->energy > band->thr) {
542
1846360
        a  = log2f(band->energy);
543
1846360
        pe = a - log2f(band->thr);
544
1846360
        band->active_lines = band->nz_lines;
545
1846360
        if (pe < PSY_3GPP_C1) {
546
867556
            pe = pe * PSY_3GPP_C3 + PSY_3GPP_C2;
547
867556
            a  = a  * PSY_3GPP_C3 + PSY_3GPP_C2;
548
867556
            band->active_lines *= PSY_3GPP_C3;
549
        }
550
1846360
        band->pe       = pe * band->nz_lines;
551
1846360
        band->pe_const = a  * band->nz_lines;
552
    }
553
554
1978697
    return band->pe;
555
}
556
557
29080
static float calc_reduction_3gpp(float a, float desired_pe, float pe,
558
                                 float active_lines)
559
{
560
    float thr_avg, reduction;
561
562
29080
    if(active_lines == 0.0)
563
56
        return 0;
564
565
29024
    thr_avg   = exp2f((a - pe) / (4.0f * active_lines));
566
29024
    reduction = exp2f((a - desired_pe) / (4.0f * active_lines)) - thr_avg;
567
568
29024
    return FFMAX(reduction, 0.0f);
569
}
570
571
1386728
static float calc_reduced_thr_3gpp(AacPsyBand *band, float min_snr,
572
                                   float reduction)
573
{
574
1386728
    float thr = band->thr;
575
576
1386728
    if (band->energy > thr) {
577
1297690
        thr = sqrtf(thr);
578
1297690
        thr = sqrtf(thr) + reduction;
579
1297690
        thr *= thr;
580
1297690
        thr *= thr;
581
582
        /* This deviates from the 3GPP spec to match the reference encoder.
583
         * It performs min(thr_reduced, max(thr, energy/min_snr)) only for bands
584
         * that have hole avoidance on (active or inactive). It always reduces the
585
         * threshold of bands with hole avoidance off.
586
         */
587

1297690
        if (thr > band->energy * min_snr && band->avoid_holes != PSY_3GPP_AH_NONE) {
588
393499
            thr = FFMAX(band->thr, band->energy * min_snr);
589
393499
            band->avoid_holes = PSY_3GPP_AH_ACTIVE;
590
        }
591
    }
592
593
1386728
    return thr;
594
}
595
596
#ifndef calc_thr_3gpp
597
11739
static void calc_thr_3gpp(const FFPsyWindowInfo *wi, const int num_bands, AacPsyChannel *pch,
598
                          const uint8_t *band_sizes, const float *coefs, const int cutoff)
599
{
600
    int i, w, g;
601
11739
    int start = 0, wstart = 0;
602
25340
    for (w = 0; w < wi->num_windows*16; w += 16) {
603
13601
        wstart = 0;
604
605570
        for (g = 0; g < num_bands; g++) {
605
591969
            AacPsyBand *band = &pch->band[w+g];
606
607
591969
            float form_factor = 0.0f;
608
            float Temp;
609
591969
            band->energy = 0.0f;
610
591969
            if (wstart < cutoff) {
611
11867344
                for (i = 0; i < band_sizes[g]; i++) {
612
11293088
                    band->energy += coefs[start+i] * coefs[start+i];
613
11293088
                    form_factor  += sqrtf(fabs(coefs[start+i]));
614
                }
615
            }
616
591969
            Temp = band->energy > 0 ? sqrtf((float)band_sizes[g] / band->energy) : 0;
617
591969
            band->thr      = band->energy * 0.001258925f;
618
591969
            band->nz_lines = form_factor * sqrtf(Temp);
619
620
591969
            start += band_sizes[g];
621
591969
            wstart += band_sizes[g];
622
        }
623
    }
624
11739
}
625
#endif /* calc_thr_3gpp */
626
627
#ifndef psy_hp_filter
628
7188
static void psy_hp_filter(const float *firbuf, float *hpfsmpl, const float *psy_fir_coeffs)
629
{
630
    int i, j;
631
7367700
    for (i = 0; i < AAC_BLOCK_SIZE_LONG; i++) {
632
        float sum1, sum2;
633
7360512
        sum1 = firbuf[i + (PSY_LAME_FIR_LEN - 1) / 2];
634
7360512
        sum2 = 0.0;
635
44163072
        for (j = 0; j < ((PSY_LAME_FIR_LEN - 1) / 2) - 1; j += 2) {
636
36802560
            sum1 += psy_fir_coeffs[j] * (firbuf[i + j] + firbuf[i + PSY_LAME_FIR_LEN - j]);
637
36802560
            sum2 += psy_fir_coeffs[j + 1] * (firbuf[i + j + 1] + firbuf[i + PSY_LAME_FIR_LEN - j - 1]);
638
        }
639
        /* NOTE: The LAME psymodel expects it's input in the range -32768 to 32768.
640
         *       Tuning this for normalized floats would be difficult. */
641
7360512
        hpfsmpl[i] = (sum1 + sum2) * 32768.0f;
642
    }
643
7188
}
644
#endif /* psy_hp_filter */
645
646
/**
647
 * Calculate band thresholds as suggested in 3GPP TS26.403
648
 */
649
11739
static void psy_3gpp_analyze_channel(FFPsyContext *ctx, int channel,
650
                                     const float *coefs, const FFPsyWindowInfo *wi)
651
{
652
11739
    AacPsyContext *pctx = (AacPsyContext*) ctx->model_priv_data;
653
11739
    AacPsyChannel *pch  = &pctx->ch[channel];
654
    int i, w, g;
655
11739
    float desired_bits, desired_pe, delta_pe, reduction= NAN, spread_en[128] = {0};
656
11739
    float a = 0.0f, active_lines = 0.0f, norm_fac = 0.0f;
657

11739
    float pe = pctx->chan_bitrate > 32000 ? 0.0f : FFMAX(50.0f, 100.0f - pctx->chan_bitrate * 100.0f / 32000.0f);
658
11739
    const int      num_bands   = ctx->num_bands[wi->num_windows == 8];
659
11739
    const uint8_t *band_sizes  = ctx->bands[wi->num_windows == 8];
660
11739
    AacPsyCoeffs  *coeffs      = pctx->psy_coef[wi->num_windows == 8];
661
11739
    const float avoid_hole_thr = wi->num_windows == 8 ? PSY_3GPP_AH_THR_SHORT : PSY_3GPP_AH_THR_LONG;
662


11739
    const int bandwidth        = ctx->cutoff ? ctx->cutoff : AAC_CUTOFF(ctx->avctx);
663
11739
    const int cutoff           = bandwidth * 2048 / wi->num_windows / ctx->avctx->sample_rate;
664
665
    //calculate energies, initial thresholds and related values - 5.4.2 "Threshold Calculation"
666
11739
    calc_thr_3gpp(wi, num_bands, pch, band_sizes, coefs, cutoff);
667
668
    //modify thresholds and energies - spread, threshold in quiet, pre-echo control
669
25340
    for (w = 0; w < wi->num_windows*16; w += 16) {
670
13601
        AacPsyBand *bands = &pch->band[w];
671
672
        /* 5.4.2.3 "Spreading" & 5.4.3 "Spread Energy Calculation" */
673
13601
        spread_en[0] = bands[0].energy;
674
591969
        for (g = 1; g < num_bands; g++) {
675
578368
            bands[g].thr   = FFMAX(bands[g].thr,    bands[g-1].thr * coeffs[g].spread_hi[0]);
676
578368
            spread_en[w+g] = FFMAX(bands[g].energy, spread_en[w+g-1] * coeffs[g].spread_hi[1]);
677
        }
678
591969
        for (g = num_bands - 2; g >= 0; g--) {
679
578368
            bands[g].thr   = FFMAX(bands[g].thr,   bands[g+1].thr * coeffs[g].spread_low[0]);
680
578368
            spread_en[w+g] = FFMAX(spread_en[w+g], spread_en[w+g+1] * coeffs[g].spread_low[1]);
681
        }
682
        //5.4.2.4 "Threshold in quiet"
683
605570
        for (g = 0; g < num_bands; g++) {
684
591969
            AacPsyBand *band = &bands[g];
685
686
591969
            band->thr_quiet = band->thr = FFMAX(band->thr, coeffs[g].ath);
687
            //5.4.2.5 "Pre-echo control"
688

591969
            if (!(wi->window_type[0] == LONG_STOP_SEQUENCE || (!w && wi->window_type[1] == LONG_START_SEQUENCE)))
689

584332
                band->thr = FFMAX(PSY_3GPP_RPEMIN*band->thr, FFMIN(band->thr,
690
                                  PSY_3GPP_RPELEV*pch->prev_band[w+g].thr_quiet));
691
692
            /* 5.6.1.3.1 "Preparatory steps of the perceptual entropy calculation" */
693
591969
            pe += calc_pe_3gpp(band);
694
591969
            a  += band->pe_const;
695
591969
            active_lines += band->active_lines;
696
697
            /* 5.6.1.3.3 "Selection of the bands for avoidance of holes" */
698

591969
            if (spread_en[w+g] * avoid_hole_thr > band->energy || coeffs[g].min_snr > 1.0f)
699
300
                band->avoid_holes = PSY_3GPP_AH_NONE;
700
            else
701
591669
                band->avoid_holes = PSY_3GPP_AH_INACTIVE;
702
        }
703
    }
704
705
    /* 5.6.1.3.2 "Calculation of the desired perceptual entropy" */
706
11739
    ctx->ch[channel].entropy = pe;
707
11739
    if (ctx->avctx->flags & AV_CODEC_FLAG_QSCALE) {
708
        /* (2.5 * 120) achieves almost transparent rate, and we want to give
709
         * ample room downwards, so we make that equivalent to QSCALE=2.4
710
         */
711
        desired_pe = pe * (ctx->avctx->global_quality ? ctx->avctx->global_quality : 120) / (2 * 2.5f * 120.0f);
712
        desired_bits = FFMIN(2560, PSY_3GPP_PE_TO_BITS(desired_pe));
713
        desired_pe = PSY_3GPP_BITS_TO_PE(desired_bits); // reflect clipping
714
715
        /* PE slope smoothing */
716
        if (ctx->bitres.bits > 0) {
717
            desired_bits = FFMIN(2560, PSY_3GPP_PE_TO_BITS(desired_pe));
718
            desired_pe = PSY_3GPP_BITS_TO_PE(desired_bits); // reflect clipping
719
        }
720
721
        pctx->pe.max = FFMAX(pe, pctx->pe.max);
722
        pctx->pe.min = FFMIN(pe, pctx->pe.min);
723
    } else {
724
11739
        desired_bits = calc_bit_demand(pctx, pe, ctx->bitres.bits, ctx->bitres.size, wi->num_windows == 8);
725
11739
        desired_pe = PSY_3GPP_BITS_TO_PE(desired_bits);
726
727
        /* NOTE: PE correction is kept simple. During initial testing it had very
728
         *       little effect on the final bitrate. Probably a good idea to come
729
         *       back and do more testing later.
730
         */
731
11739
        if (ctx->bitres.bits > 0)
732
11678
            desired_pe *= av_clipf(pctx->pe.previous / PSY_3GPP_BITS_TO_PE(ctx->bitres.bits),
733
                                   0.85f, 1.15f);
734
    }
735
11739
    pctx->pe.previous = PSY_3GPP_BITS_TO_PE(desired_bits);
736
11739
    ctx->bitres.alloc = desired_bits;
737
738
11739
    if (desired_pe < pe) {
739
        /* 5.6.1.3.4 "First Estimation of the reduction value" */
740
24468
        for (w = 0; w < wi->num_windows*16; w += 16) {
741
12850
            reduction = calc_reduction_3gpp(a, desired_pe, pe, active_lines);
742
12850
            pe = 0.0f;
743
12850
            a  = 0.0f;
744
12850
            active_lines = 0.0f;
745
593220
            for (g = 0; g < num_bands; g++) {
746
580370
                AacPsyBand *band = &pch->band[w+g];
747
748
580370
                band->thr = calc_reduced_thr_3gpp(band, coeffs[g].min_snr, reduction);
749
                /* recalculate PE */
750
580370
                pe += calc_pe_3gpp(band);
751
580370
                a  += band->pe_const;
752
580370
                active_lines += band->active_lines;
753
            }
754
        }
755
756
        /* 5.6.1.3.5 "Second Estimation of the reduction value" */
757
20842
        for (i = 0; i < 2; i++) {
758
16230
            float pe_no_ah = 0.0f, desired_pe_no_ah;
759
16230
            active_lines = a = 0.0f;
760
33692
            for (w = 0; w < wi->num_windows*16; w += 16) {
761
823820
                for (g = 0; g < num_bands; g++) {
762
806358
                    AacPsyBand *band = &pch->band[w+g];
763
764
806358
                    if (band->avoid_holes != PSY_3GPP_AH_ACTIVE) {
765
654724
                        pe_no_ah += band->pe;
766
654724
                        a        += band->pe_const;
767
654724
                        active_lines += band->active_lines;
768
                    }
769
                }
770
            }
771
16230
            desired_pe_no_ah = FFMAX(desired_pe - (pe - pe_no_ah), 0.0f);
772
16230
            if (active_lines > 0.0f)
773
16230
                reduction = calc_reduction_3gpp(a, desired_pe_no_ah, pe_no_ah, active_lines);
774
775
16230
            pe = 0.0f;
776
33692
            for (w = 0; w < wi->num_windows*16; w += 16) {
777
823820
                for (g = 0; g < num_bands; g++) {
778
806358
                    AacPsyBand *band = &pch->band[w+g];
779
780
806358
                    if (active_lines > 0.0f)
781
806358
                        band->thr = calc_reduced_thr_3gpp(band, coeffs[g].min_snr, reduction);
782
806358
                    pe += calc_pe_3gpp(band);
783
806358
                    if (band->thr > 0.0f)
784
806358
                        band->norm_fac = band->active_lines / band->thr;
785
                    else
786
                        band->norm_fac = 0.0f;
787
806358
                    norm_fac += band->norm_fac;
788
                }
789
            }
790
16230
            delta_pe = desired_pe - pe;
791
16230
            if (fabs(delta_pe) > 0.05f * desired_pe)
792
7006
                break;
793
        }
794
795
11618
        if (pe < 1.15f * desired_pe) {
796
            /* 6.6.1.3.6 "Final threshold modification by linearization" */
797
6525
            norm_fac = 1.0f / norm_fac;
798
13050
            for (w = 0; w < wi->num_windows*16; w += 16) {
799
326250
                for (g = 0; g < num_bands; g++) {
800
319725
                    AacPsyBand *band = &pch->band[w+g];
801
802
319725
                    if (band->active_lines > 0.5f) {
803
293570
                        float delta_sfb_pe = band->norm_fac * norm_fac * delta_pe;
804
293570
                        float thr = band->thr;
805
806
293570
                        thr *= exp2f(delta_sfb_pe / band->active_lines);
807

293570
                        if (thr > coeffs[g].min_snr * band->energy && band->avoid_holes == PSY_3GPP_AH_INACTIVE)
808
73
                            thr = FFMAX(band->thr, coeffs[g].min_snr * band->energy);
809
293570
                        band->thr = thr;
810
                    }
811
                }
812
            }
813
        } else {
814
            /* 5.6.1.3.7 "Further perceptual entropy reduction" */
815
5093
            g = num_bands;
816

248062
            while (pe > desired_pe && g--) {
817
503186
                for (w = 0; w < wi->num_windows*16; w+= 16) {
818
260217
                    AacPsyBand *band = &pch->band[w+g];
819

260217
                    if (band->avoid_holes != PSY_3GPP_AH_NONE && coeffs[g].min_snr < PSY_SNR_1DB) {
820
400
                        coeffs[g].min_snr = PSY_SNR_1DB;
821
400
                        band->thr = band->energy * PSY_SNR_1DB;
822
400
                        pe += band->active_lines * 1.5f - band->pe;
823
                    }
824
                }
825
            }
826
            /* TODO: allow more holes (unused without mid/side) */
827
        }
828
    }
829
830
25340
    for (w = 0; w < wi->num_windows*16; w += 16) {
831
605570
        for (g = 0; g < num_bands; g++) {
832
591969
            AacPsyBand *band     = &pch->band[w+g];
833
591969
            FFPsyBand  *psy_band = &ctx->ch[channel].psy_bands[w+g];
834
835
591969
            psy_band->threshold = band->thr;
836
591969
            psy_band->energy    = band->energy;
837
591969
            psy_band->spread    = band->active_lines * 2.0f / band_sizes[g];
838
591969
            psy_band->bits      = PSY_3GPP_PE_TO_BITS(band->pe);
839
        }
840
    }
841
842
11739
    memcpy(pch->prev_band, pch->band, sizeof(pch->band));
843
11739
}
844
845
6467
static void psy_3gpp_analyze(FFPsyContext *ctx, int channel,
846
                                   const float **coeffs, const FFPsyWindowInfo *wi)
847
{
848
    int ch;
849
6467
    FFPsyChannelGroup *group = ff_psy_find_group(ctx, channel);
850
851
18206
    for (ch = 0; ch < group->num_ch; ch++)
852
11739
        psy_3gpp_analyze_channel(ctx, channel + ch, coeffs[ch], &wi[ch]);
853
6467
}
854
855
11
static av_cold void psy_3gpp_end(FFPsyContext *apc)
856
{
857
11
    AacPsyContext *pctx = (AacPsyContext*) apc->model_priv_data;
858
11
    av_freep(&pctx->ch);
859
11
    av_freep(&apc->model_priv_data);
860
11
}
861
862
7236
static void lame_apply_block_type(AacPsyChannel *ctx, FFPsyWindowInfo *wi, int uselongblock)
863
{
864
7236
    int blocktype = ONLY_LONG_SEQUENCE;
865
7236
    if (uselongblock) {
866
7073
        if (ctx->next_window_seq == EIGHT_SHORT_SEQUENCE)
867
120
            blocktype = LONG_STOP_SEQUENCE;
868
    } else {
869
163
        blocktype = EIGHT_SHORT_SEQUENCE;
870
163
        if (ctx->next_window_seq == ONLY_LONG_SEQUENCE)
871
119
            ctx->next_window_seq = LONG_START_SEQUENCE;
872
163
        if (ctx->next_window_seq == LONG_STOP_SEQUENCE)
873
18
            ctx->next_window_seq = EIGHT_SHORT_SEQUENCE;
874
    }
875
876
7236
    wi->window_type[0] = ctx->next_window_seq;
877
7236
    ctx->next_window_seq = blocktype;
878
7236
}
879
880
7236
static FFPsyWindowInfo psy_lame_window(FFPsyContext *ctx, const float *audio,
881
                                       const float *la, int channel, int prev_type)
882
{
883
7236
    AacPsyContext *pctx = (AacPsyContext*) ctx->model_priv_data;
884
7236
    AacPsyChannel *pch  = &pctx->ch[channel];
885
7236
    int grouping     = 0;
886
7236
    int uselongblock = 1;
887
7236
    int attacks[AAC_NUM_BLOCKS_SHORT + 1] = { 0 };
888
    int i;
889
7236
    FFPsyWindowInfo wi = { { 0 } };
890
891
7236
    if (la) {
892
        float hpfsmpl[AAC_BLOCK_SIZE_LONG];
893
7188
        const float *pf = hpfsmpl;
894
        float attack_intensity[(AAC_NUM_BLOCKS_SHORT + 1) * PSY_LAME_NUM_SUBBLOCKS];
895
        float energy_subshort[(AAC_NUM_BLOCKS_SHORT + 1) * PSY_LAME_NUM_SUBBLOCKS];
896
7188
        float energy_short[AAC_NUM_BLOCKS_SHORT + 1] = { 0 };
897
7188
        const float *firbuf = la + (AAC_BLOCK_SIZE_SHORT/4 - PSY_LAME_FIR_LEN);
898
7188
        int att_sum = 0;
899
900
        /* LAME comment: apply high pass filter of fs/4 */
901
7188
        psy_hp_filter(firbuf, hpfsmpl, psy_fir_coeffs);
902
903
        /* Calculate the energies of each sub-shortblock */
904
28752
        for (i = 0; i < PSY_LAME_NUM_SUBBLOCKS; i++) {
905
21564
            energy_subshort[i] = pch->prev_energy_subshort[i + ((AAC_NUM_BLOCKS_SHORT - 1) * PSY_LAME_NUM_SUBBLOCKS)];
906
            assert(pch->prev_energy_subshort[i + ((AAC_NUM_BLOCKS_SHORT - 2) * PSY_LAME_NUM_SUBBLOCKS + 1)] > 0);
907
21564
            attack_intensity[i] = energy_subshort[i] / pch->prev_energy_subshort[i + ((AAC_NUM_BLOCKS_SHORT - 2) * PSY_LAME_NUM_SUBBLOCKS + 1)];
908
21564
            energy_short[0] += energy_subshort[i];
909
        }
910
911
179700
        for (i = 0; i < AAC_NUM_BLOCKS_SHORT * PSY_LAME_NUM_SUBBLOCKS; i++) {
912
172512
            const float *const pfe = pf + AAC_BLOCK_SIZE_LONG / (AAC_NUM_BLOCKS_SHORT * PSY_LAME_NUM_SUBBLOCKS);
913
172512
            float p = 1.0f;
914
7418016
            for (; pf < pfe; pf++)
915
7245504
                p = FFMAX(p, fabsf(*pf));
916
172512
            pch->prev_energy_subshort[i] = energy_subshort[i + PSY_LAME_NUM_SUBBLOCKS] = p;
917
172512
            energy_short[1 + i / PSY_LAME_NUM_SUBBLOCKS] += p;
918
            /* NOTE: The indexes below are [i + 3 - 2] in the LAME source.
919
             *       Obviously the 3 and 2 have some significance, or this would be just [i + 1]
920
             *       (which is what we use here). What the 3 stands for is ambiguous, as it is both
921
             *       number of short blocks, and the number of sub-short blocks.
922
             *       It seems that LAME is comparing each sub-block to sub-block + 1 in the
923
             *       previous block.
924
             */
925
172512
            if (p > energy_subshort[i + 1])
926
85320
                p = p / energy_subshort[i + 1];
927
87192
            else if (energy_subshort[i + 1] > p * 10.0f)
928
52
                p = energy_subshort[i + 1] / (p * 10.0f);
929
            else
930
87140
                p = 0.0;
931
172512
            attack_intensity[i + PSY_LAME_NUM_SUBBLOCKS] = p;
932
        }
933
934
        /* compare energy between sub-short blocks */
935
201264
        for (i = 0; i < (AAC_NUM_BLOCKS_SHORT + 1) * PSY_LAME_NUM_SUBBLOCKS; i++)
936
194076
            if (!attacks[i / PSY_LAME_NUM_SUBBLOCKS])
937
193893
                if (attack_intensity[i] > pch->attack_threshold)
938
190
                    attacks[i / PSY_LAME_NUM_SUBBLOCKS] = (i % PSY_LAME_NUM_SUBBLOCKS) + 1;
939
940
        /* should have energy change between short blocks, in order to avoid periodic signals */
941
        /* Good samples to show the effect are Trumpet test songs */
942
        /* GB: tuned (1) to avoid too many short blocks for test sample TRUMPET */
943
        /* RH: tuned (2) to let enough short blocks through for test sample FSOL and SNAPS */
944
64692
        for (i = 1; i < AAC_NUM_BLOCKS_SHORT + 1; i++) {
945
57504
            const float u = energy_short[i - 1];
946
57504
            const float v = energy_short[i];
947
57504
            const float m = FFMAX(u, v);
948
57504
            if (m < 40000) {                          /* (2) */
949

54508
                if (u < 1.7f * v && v < 1.7f * u) {   /* (1) */
950

51265
                    if (i == 1 && attacks[0] < attacks[i])
951
9
                        attacks[0] = 0;
952
51265
                    attacks[i] = 0;
953
                }
954
            }
955
57504
            att_sum += attacks[i];
956
        }
957
958
7188
        if (attacks[0] <= pch->prev_attack)
959
7188
            attacks[0] = 0;
960
961
7188
        att_sum += attacks[0];
962
        /* 3 below indicates the previous attack happened in the last sub-block of the previous sequence */
963

7188
        if (pch->prev_attack == 3 || att_sum) {
964
146
            uselongblock = 0;
965
966
1314
            for (i = 1; i < AAC_NUM_BLOCKS_SHORT + 1; i++)
967

1168
                if (attacks[i] && attacks[i-1])
968
                    attacks[i] = 0;
969
        }
970
    } else {
971
        /* We have no lookahead info, so just use same type as the previous sequence. */
972
48
        uselongblock = !(prev_type == EIGHT_SHORT_SEQUENCE);
973
    }
974
975
7236
    lame_apply_block_type(pch, &wi, uselongblock);
976
977
7236
    wi.window_type[1] = prev_type;
978
7236
    if (wi.window_type[0] != EIGHT_SHORT_SEQUENCE) {
979
980
7072
        wi.num_windows  = 1;
981
7072
        wi.grouping[0]  = 1;
982
7072
        if (wi.window_type[0] == LONG_START_SEQUENCE)
983
119
            wi.window_shape = 0;
984
        else
985
6953
            wi.window_shape = 1;
986
987
    } else {
988
164
        int lastgrp = 0;
989
990
164
        wi.num_windows = 8;
991
164
        wi.window_shape = 0;
992
1476
        for (i = 0; i < 8; i++) {
993
1312
            if (!((pch->next_grouping >> i) & 1))
994
624
                lastgrp = i;
995
1312
            wi.grouping[lastgrp]++;
996
        }
997
    }
998
999
    /* Determine grouping, based on the location of the first attack, and save for
1000
     * the next frame.
1001
     * FIXME: Move this to analysis.
1002
     * TODO: Tune groupings depending on attack location
1003
     * TODO: Handle more than one attack in a group
1004
     */
1005
71825
    for (i = 0; i < 9; i++) {
1006
64721
        if (attacks[i]) {
1007
132
            grouping = i;
1008
132
            break;
1009
        }
1010
    }
1011
7236
    pch->next_grouping = window_grouping[grouping];
1012
1013
7236
    pch->prev_attack = attacks[8];
1014
1015
7236
    return wi;
1016
}
1017
1018
const FFPsyModel ff_aac_psy_model =
1019
{
1020
    .name    = "3GPP TS 26.403-inspired model",
1021
    .init    = psy_3gpp_init,
1022
    .window  = psy_lame_window,
1023
    .analyze = psy_3gpp_analyze,
1024
    .end     = psy_3gpp_end,
1025
};