GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/imc.c Lines: 454 565 80.4 %
Date: 2019-11-22 03:34:36 Branches: 290 372 78.0 %

Line Branch Exec Source
1
/*
2
 * IMC compatible decoder
3
 * Copyright (c) 2002-2004 Maxim Poliakovski
4
 * Copyright (c) 2006 Benjamin Larsson
5
 * Copyright (c) 2006 Konstantin Shishkov
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
 *  IMC - Intel Music Coder
27
 *  A mdct based codec using a 256 points large transform
28
 *  divided into 32 bands with some mix of scale factors.
29
 *  Only mono is supported.
30
 */
31
32
33
#include <math.h>
34
#include <stddef.h>
35
#include <stdio.h>
36
37
#include "libavutil/channel_layout.h"
38
#include "libavutil/ffmath.h"
39
#include "libavutil/float_dsp.h"
40
#include "libavutil/internal.h"
41
#include "avcodec.h"
42
#include "bswapdsp.h"
43
#include "get_bits.h"
44
#include "fft.h"
45
#include "internal.h"
46
#include "sinewin.h"
47
48
#include "imcdata.h"
49
50
#define IMC_BLOCK_SIZE 64
51
#define IMC_FRAME_ID 0x21
52
#define BANDS 32
53
#define COEFFS 256
54
55
typedef struct IMCChannel {
56
    float old_floor[BANDS];
57
    float flcoeffs1[BANDS];
58
    float flcoeffs2[BANDS];
59
    float flcoeffs3[BANDS];
60
    float flcoeffs4[BANDS];
61
    float flcoeffs5[BANDS];
62
    float flcoeffs6[BANDS];
63
    float CWdecoded[COEFFS];
64
65
    int bandWidthT[BANDS];     ///< codewords per band
66
    int bitsBandT[BANDS];      ///< how many bits per codeword in band
67
    int CWlengthT[COEFFS];     ///< how many bits in each codeword
68
    int levlCoeffBuf[BANDS];
69
    int bandFlagsBuf[BANDS];   ///< flags for each band
70
    int sumLenArr[BANDS];      ///< bits for all coeffs in band
71
    int skipFlagRaw[BANDS];    ///< skip flags are stored in raw form or not
72
    int skipFlagBits[BANDS];   ///< bits used to code skip flags
73
    int skipFlagCount[BANDS];  ///< skipped coefficients per band
74
    int skipFlags[COEFFS];     ///< skip coefficient decoding or not
75
    int codewords[COEFFS];     ///< raw codewords read from bitstream
76
77
    float last_fft_im[COEFFS];
78
79
    int decoder_reset;
80
} IMCChannel;
81
82
typedef struct IMCContext {
83
    IMCChannel chctx[2];
84
85
    /** MDCT tables */
86
    //@{
87
    float mdct_sine_window[COEFFS];
88
    float post_cos[COEFFS];
89
    float post_sin[COEFFS];
90
    float pre_coef1[COEFFS];
91
    float pre_coef2[COEFFS];
92
    //@}
93
94
    float sqrt_tab[30];
95
    GetBitContext gb;
96
97
    BswapDSPContext bdsp;
98
    AVFloatDSPContext *fdsp;
99
    FFTContext fft;
100
    DECLARE_ALIGNED(32, FFTComplex, samples)[COEFFS / 2];
101
    float *out_samples;
102
103
    int coef0_pos;
104
105
    int8_t cyclTab[32], cyclTab2[32];
106
    float  weights1[31], weights2[31];
107
108
    AVCodecContext *avctx;
109
} IMCContext;
110
111
static VLC huffman_vlc[4][4];
112
113
#define VLC_TABLES_SIZE 9512
114
115
static const int vlc_offsets[17] = {
116
    0,     640, 1156, 1732, 2308, 2852, 3396, 3924,
117
    4452, 5220, 5860, 6628, 7268, 7908, 8424, 8936, VLC_TABLES_SIZE
118
};
119
120
static VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2];
121
122
static inline double freq2bark(double freq)
123
{
124
    return 3.5 * atan((freq / 7500.0) * (freq / 7500.0)) + 13.0 * atan(freq * 0.00076);
125
}
126
127
static av_cold void iac_generate_tabs(IMCContext *q, int sampling_rate)
128
{
129
    double freqmin[32], freqmid[32], freqmax[32];
130
    double scale = sampling_rate / (256.0 * 2.0 * 2.0);
131
    double nyquist_freq = sampling_rate * 0.5;
132
    double freq, bark, prev_bark = 0, tf, tb;
133
    int i, j;
134
135
    for (i = 0; i < 32; i++) {
136
        freq = (band_tab[i] + band_tab[i + 1] - 1) * scale;
137
        bark = freq2bark(freq);
138
139
        if (i > 0) {
140
            tb = bark - prev_bark;
141
            q->weights1[i - 1] = ff_exp10(-1.0 * tb);
142
            q->weights2[i - 1] = ff_exp10(-2.7 * tb);
143
        }
144
        prev_bark = bark;
145
146
        freqmid[i] = freq;
147
148
        tf = freq;
149
        while (tf < nyquist_freq) {
150
            tf += 0.5;
151
            tb =  freq2bark(tf);
152
            if (tb > bark + 0.5)
153
                break;
154
        }
155
        freqmax[i] = tf;
156
157
        tf = freq;
158
        while (tf > 0.0) {
159
            tf -= 0.5;
160
            tb =  freq2bark(tf);
161
            if (tb <= bark - 0.5)
162
                break;
163
        }
164
        freqmin[i] = tf;
165
    }
166
167
    for (i = 0; i < 32; i++) {
168
        freq = freqmax[i];
169
        for (j = 31; j > 0 && freq <= freqmid[j]; j--);
170
        q->cyclTab[i] = j + 1;
171
172
        freq = freqmin[i];
173
        for (j = 0; j < 32 && freq >= freqmid[j]; j++);
174
        q->cyclTab2[i] = j - 1;
175
    }
176
}
177
178
2
static av_cold int imc_decode_init(AVCodecContext *avctx)
179
{
180
    int i, j, ret;
181
2
    IMCContext *q = avctx->priv_data;
182
    double r1, r2;
183
184

2
    if (avctx->codec_id == AV_CODEC_ID_IAC && avctx->sample_rate > 96000) {
185
        av_log(avctx, AV_LOG_ERROR,
186
               "Strange sample rate of %i, file likely corrupt or "
187
               "needing a new table derivation method.\n",
188
               avctx->sample_rate);
189
        return AVERROR_PATCHWELCOME;
190
    }
191
192
2
    if (avctx->codec_id == AV_CODEC_ID_IMC)
193
2
        avctx->channels = 1;
194
195
2
    if (avctx->channels > 2) {
196
        avpriv_request_sample(avctx, "Number of channels > 2");
197
        return AVERROR_PATCHWELCOME;
198
    }
199
200
4
    for (j = 0; j < avctx->channels; j++) {
201
2
        q->chctx[j].decoder_reset = 1;
202
203
66
        for (i = 0; i < BANDS; i++)
204
64
            q->chctx[j].old_floor[i] = 1.0;
205
206
258
        for (i = 0; i < COEFFS / 2; i++)
207
256
            q->chctx[j].last_fft_im[i] = 0;
208
    }
209
210
    /* Build mdct window, a simple sine window normalized with sqrt(2) */
211
2
    ff_sine_window_init(q->mdct_sine_window, COEFFS);
212
514
    for (i = 0; i < COEFFS; i++)
213
512
        q->mdct_sine_window[i] *= sqrt(2.0);
214
258
    for (i = 0; i < COEFFS / 2; i++) {
215
256
        q->post_cos[i] = (1.0f / 32768) * cos(i / 256.0 * M_PI);
216
256
        q->post_sin[i] = (1.0f / 32768) * sin(i / 256.0 * M_PI);
217
218
256
        r1 = sin((i * 4.0 + 1.0) / 1024.0 * M_PI);
219
256
        r2 = cos((i * 4.0 + 1.0) / 1024.0 * M_PI);
220
221
256
        if (i & 0x1) {
222
128
            q->pre_coef1[i] =  (r1 + r2) * sqrt(2.0);
223
128
            q->pre_coef2[i] = -(r1 - r2) * sqrt(2.0);
224
        } else {
225
128
            q->pre_coef1[i] = -(r1 + r2) * sqrt(2.0);
226
128
            q->pre_coef2[i] =  (r1 - r2) * sqrt(2.0);
227
        }
228
    }
229
230
    /* Generate a square root table */
231
232
62
    for (i = 0; i < 30; i++)
233
60
        q->sqrt_tab[i] = sqrt(i);
234
235
    /* initialize the VLC tables */
236
10
    for (i = 0; i < 4 ; i++) {
237
40
        for (j = 0; j < 4; j++) {
238
32
            huffman_vlc[i][j].table = &vlc_tables[vlc_offsets[i * 4 + j]];
239
32
            huffman_vlc[i][j].table_allocated = vlc_offsets[i * 4 + j + 1] - vlc_offsets[i * 4 + j];
240
32
            init_vlc(&huffman_vlc[i][j], 9, imc_huffman_sizes[i],
241
                     imc_huffman_lens[i][j], 1, 1,
242
                     imc_huffman_bits[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC);
243
        }
244
    }
245
246
2
    if (avctx->codec_id == AV_CODEC_ID_IAC) {
247
        iac_generate_tabs(q, avctx->sample_rate);
248
    } else {
249
2
        memcpy(q->cyclTab,  cyclTab,  sizeof(cyclTab));
250
2
        memcpy(q->cyclTab2, cyclTab2, sizeof(cyclTab2));
251
2
        memcpy(q->weights1, imc_weights1, sizeof(imc_weights1));
252
2
        memcpy(q->weights2, imc_weights2, sizeof(imc_weights2));
253
    }
254
255
2
    if ((ret = ff_fft_init(&q->fft, 7, 1))) {
256
        av_log(avctx, AV_LOG_INFO, "FFT init failed\n");
257
        return ret;
258
    }
259
2
    ff_bswapdsp_init(&q->bdsp);
260
2
    q->fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT);
261
2
    if (!q->fdsp) {
262
        ff_fft_end(&q->fft);
263
264
        return AVERROR(ENOMEM);
265
    }
266
267
2
    avctx->sample_fmt     = AV_SAMPLE_FMT_FLTP;
268
4
    avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO
269
2
                                                 : AV_CH_LAYOUT_STEREO;
270
271
2
    return 0;
272
}
273
274
1311
static void imc_calculate_coeffs(IMCContext *q, float *flcoeffs1,
275
                                 float *flcoeffs2, int *bandWidthT,
276
                                 float *flcoeffs3, float *flcoeffs5)
277
{
278
    float   workT1[BANDS];
279
    float   workT2[BANDS];
280
    float   workT3[BANDS];
281
1311
    float   snr_limit = 1.e-30;
282
1311
    float   accum = 0.0;
283
    int i, cnt2;
284
285
43263
    for (i = 0; i < BANDS; i++) {
286
41952
        flcoeffs5[i] = workT2[i] = 0.0;
287
41952
        if (bandWidthT[i]) {
288
37499
            workT1[i] = flcoeffs1[i] * flcoeffs1[i];
289
37499
            flcoeffs3[i] = 2.0 * flcoeffs2[i];
290
        } else {
291
4453
            workT1[i]    = 0.0;
292
4453
            flcoeffs3[i] = -30000.0;
293
        }
294
41952
        workT3[i] = bandWidthT[i] * workT1[i] * 0.01;
295
41952
        if (workT3[i] <= snr_limit)
296
4453
            workT3[i] = 0.0;
297
    }
298
299
43263
    for (i = 0; i < BANDS; i++) {
300
100947
        for (cnt2 = i; cnt2 < q->cyclTab[i]; cnt2++)
301
58995
            flcoeffs5[cnt2] = flcoeffs5[cnt2] + workT3[i];
302
41952
        workT2[cnt2 - 1] = workT2[cnt2 - 1] + workT3[i];
303
    }
304
305
41952
    for (i = 1; i < BANDS; i++) {
306
40641
        accum = (workT2[i - 1] + accum) * q->weights1[i - 1];
307
40641
        flcoeffs5[i] += accum;
308
    }
309
310
43263
    for (i = 0; i < BANDS; i++)
311
41952
        workT2[i] = 0.0;
312
313
43263
    for (i = 0; i < BANDS; i++) {
314
58995
        for (cnt2 = i - 1; cnt2 > q->cyclTab2[i]; cnt2--)
315
17043
            flcoeffs5[cnt2] += workT3[i];
316
41952
        workT2[cnt2+1] += workT3[i];
317
    }
318
319
1311
    accum = 0.0;
320
321
41952
    for (i = BANDS-2; i >= 0; i--) {
322
40641
        accum = (workT2[i+1] + accum) * q->weights2[i];
323
40641
        flcoeffs5[i] += accum;
324
        // there is missing code here, but it seems to never be triggered
325
    }
326
1311
}
327
328
329
1311
static void imc_read_level_coeffs(IMCContext *q, int stream_format_code,
330
                                  int *levlCoeffs)
331
{
332
    int i;
333
    VLC *hufftab[4];
334
1311
    int start = 0;
335
    const uint8_t *cb_sel;
336
    int s;
337
338
1311
    s = stream_format_code >> 1;
339
1311
    hufftab[0] = &huffman_vlc[s][0];
340
1311
    hufftab[1] = &huffman_vlc[s][1];
341
1311
    hufftab[2] = &huffman_vlc[s][2];
342
1311
    hufftab[3] = &huffman_vlc[s][3];
343
1311
    cb_sel = imc_cb_select[s];
344
345
1311
    if (stream_format_code & 4)
346
305
        start = 1;
347
1311
    if (start)
348
305
        levlCoeffs[0] = get_bits(&q->gb, 7);
349
42958
    for (i = start; i < BANDS; i++) {
350
83294
        levlCoeffs[i] = get_vlc2(&q->gb, hufftab[cb_sel[i]]->table,
351
41647
                                 hufftab[cb_sel[i]]->bits, 2);
352
41647
        if (levlCoeffs[i] == 17)
353
            levlCoeffs[i] += get_bits(&q->gb, 4);
354
    }
355
1311
}
356
357
static void imc_read_level_coeffs_raw(IMCContext *q, int stream_format_code,
358
                                      int *levlCoeffs)
359
{
360
    int i;
361
362
    q->coef0_pos  = get_bits(&q->gb, 5);
363
    levlCoeffs[0] = get_bits(&q->gb, 7);
364
    for (i = 1; i < BANDS; i++)
365
        levlCoeffs[i] = get_bits(&q->gb, 4);
366
}
367
368
305
static void imc_decode_level_coefficients(IMCContext *q, int *levlCoeffBuf,
369
                                          float *flcoeffs1, float *flcoeffs2)
370
{
371
    int i, level;
372
    float tmp, tmp2;
373
    // maybe some frequency division thingy
374
375
305
    flcoeffs1[0] = 20000.0 / exp2 (levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
376
305
    flcoeffs2[0] = log2f(flcoeffs1[0]);
377
305
    tmp  = flcoeffs1[0];
378
305
    tmp2 = flcoeffs2[0];
379
380
9760
    for (i = 1; i < BANDS; i++) {
381
9455
        level = levlCoeffBuf[i];
382
9455
        if (level == 16) {
383
950
            flcoeffs1[i] = 1.0;
384
950
            flcoeffs2[i] = 0.0;
385
        } else {
386
8505
            if (level < 17)
387
8505
                level -= 7;
388
            else if (level <= 24)
389
                level -= 32;
390
            else
391
                level -= 16;
392
393
8505
            tmp  *= imc_exp_tab[15 + level];
394
8505
            tmp2 += 0.83048 * level;  // 0.83048 = log2(10) * 0.25
395
8505
            flcoeffs1[i] = tmp;
396
8505
            flcoeffs2[i] = tmp2;
397
        }
398
    }
399
305
}
400
401
402
1006
static void imc_decode_level_coefficients2(IMCContext *q, int *levlCoeffBuf,
403
                                           float *old_floor, float *flcoeffs1,
404
                                           float *flcoeffs2)
405
{
406
    int i;
407
    /* FIXME maybe flag_buf = noise coding and flcoeffs1 = new scale factors
408
     *       and flcoeffs2 old scale factors
409
     *       might be incomplete due to a missing table that is in the binary code
410
     */
411
33198
    for (i = 0; i < BANDS; i++) {
412
32192
        flcoeffs1[i] = 0;
413
32192
        if (levlCoeffBuf[i] < 16) {
414
28689
            flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i];
415
28689
            flcoeffs2[i] = (levlCoeffBuf[i] - 7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25
416
        } else {
417
3503
            flcoeffs1[i] = old_floor[i];
418
        }
419
    }
420
1006
}
421
422
static void imc_decode_level_coefficients_raw(IMCContext *q, int *levlCoeffBuf,
423
                                              float *flcoeffs1, float *flcoeffs2)
424
{
425
    int i, level, pos;
426
    float tmp, tmp2;
427
428
    pos = q->coef0_pos;
429
    flcoeffs1[pos] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
430
    flcoeffs2[pos] = log2f(flcoeffs1[pos]);
431
    tmp  = flcoeffs1[pos];
432
    tmp2 = flcoeffs2[pos];
433
434
    levlCoeffBuf++;
435
    for (i = 0; i < BANDS; i++) {
436
        if (i == pos)
437
            continue;
438
        level = *levlCoeffBuf++;
439
        flcoeffs1[i] = tmp  * powf(10.0, -level * 0.4375); //todo tab
440
        flcoeffs2[i] = tmp2 - 1.4533435415 * level; // 1.4533435415 = log2(10) * 0.4375
441
    }
442
}
443
444
/**
445
 * Perform bit allocation depending on bits available
446
 */
447
1311
static int bit_allocation(IMCContext *q, IMCChannel *chctx,
448
                          int stream_format_code, int freebits, int flag)
449
{
450
    int i, j;
451
1311
    const float limit = -1.e20;
452
1311
    float highest = 0.0;
453
    int indx;
454
1311
    int t1 = 0;
455
1311
    int t2 = 1;
456
1311
    float summa = 0.0;
457
1311
    int iacc = 0;
458
1311
    int summer = 0;
459
    int rres, cwlen;
460
1311
    float lowest = 1.e10;
461
1311
    int low_indx = 0;
462
    float workT[32];
463
    int flg;
464
1311
    int found_indx = 0;
465
466
43263
    for (i = 0; i < BANDS; i++)
467
41952
        highest = FFMAX(highest, chctx->flcoeffs1[i]);
468
469
41952
    for (i = 0; i < BANDS - 1; i++) {
470
40641
        if (chctx->flcoeffs5[i] <= 0) {
471
            av_log(q->avctx, AV_LOG_ERROR, "flcoeffs5 %f invalid\n", chctx->flcoeffs5[i]);
472
            return AVERROR_INVALIDDATA;
473
        }
474
40641
        chctx->flcoeffs4[i] = chctx->flcoeffs3[i] - log2f(chctx->flcoeffs5[i]);
475
    }
476
1311
    chctx->flcoeffs4[BANDS - 1] = limit;
477
478
1311
    highest = highest * 0.25;
479
480
43263
    for (i = 0; i < BANDS; i++) {
481
41952
        indx = -1;
482
41952
        if ((band_tab[i + 1] - band_tab[i]) == chctx->bandWidthT[i])
483
37499
            indx = 0;
484
485
41952
        if ((band_tab[i + 1] - band_tab[i]) > chctx->bandWidthT[i])
486
4453
            indx = 1;
487
488
41952
        if (((band_tab[i + 1] - band_tab[i]) / 2) >= chctx->bandWidthT[i])
489
4453
            indx = 2;
490
491
41952
        if (indx == -1)
492
            return AVERROR_INVALIDDATA;
493
494
41952
        chctx->flcoeffs4[i] += xTab[(indx * 2 + (chctx->flcoeffs1[i] < highest)) * 2 + flag];
495
    }
496
497
1311
    if (stream_format_code & 0x2) {
498
1179
        chctx->flcoeffs4[0] = limit;
499
1179
        chctx->flcoeffs4[1] = limit;
500
1179
        chctx->flcoeffs4[2] = limit;
501
1179
        chctx->flcoeffs4[3] = limit;
502
    }
503
504
37236
    for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS - 1; i++) {
505
35925
        iacc  += chctx->bandWidthT[i];
506
35925
        summa += chctx->bandWidthT[i] * chctx->flcoeffs4[i];
507
    }
508
509
1311
    if (!iacc)
510
        return AVERROR_INVALIDDATA;
511
512
1311
    chctx->bandWidthT[BANDS - 1] = 0;
513
1311
    summa = (summa * 0.5 - freebits) / iacc;
514
515
516
4317
    for (i = 0; i < BANDS / 2; i++) {
517
4312
        rres = summer - freebits;
518

4312
        if ((rres >= -8) && (rres <= 8))
519
1306
            break;
520
521
3006
        summer = 0;
522
3006
        iacc   = 0;
523
524
88174
        for (j = (stream_format_code & 0x2) ? 4 : 0; j < BANDS; j++) {
525
85168
            cwlen = av_clipf(((chctx->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6);
526
527
85168
            chctx->bitsBandT[j] = cwlen;
528
85168
            summer += chctx->bandWidthT[j] * cwlen;
529
530
85168
            if (cwlen > 0)
531
68392
                iacc += chctx->bandWidthT[j];
532
        }
533
534
3006
        flg = t2;
535
3006
        t2 = 1;
536
3006
        if (freebits < summer)
537
1367
            t2 = -1;
538
3006
        if (i == 0)
539
1311
            flg = t2;
540
3006
        if (flg != t2)
541
1174
            t1++;
542
543
3006
        summa = (float)(summer - freebits) / ((t1 + 1) * iacc) + summa;
544
    }
545
546
38547
    for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS; i++) {
547
358704
        for (j = band_tab[i]; j < band_tab[i + 1]; j++)
548
321468
            chctx->CWlengthT[j] = chctx->bitsBandT[i];
549
    }
550
551
1311
    if (freebits > summer) {
552
19602
        for (i = 0; i < BANDS; i++) {
553
19008
            workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
554
19008
                                              : (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
555
        }
556
557
594
        highest = 0.0;
558
559
        do {
560
641
            if (highest <= -1.e20)
561
                break;
562
563
641
            found_indx = 0;
564
641
            highest = -1.e20;
565
566
21153
            for (i = 0; i < BANDS; i++) {
567
20512
                if (workT[i] > highest) {
568
2365
                    highest = workT[i];
569
2365
                    found_indx = i;
570
                }
571
            }
572
573
641
            if (highest > -1.e20) {
574
641
                workT[found_indx] -= 2.0;
575
641
                if (++chctx->bitsBandT[found_indx] == 6)
576
                    workT[found_indx] = -1.e20;
577
578

3097
                for (j = band_tab[found_indx]; j < band_tab[found_indx + 1] && (freebits > summer); j++) {
579
2456
                    chctx->CWlengthT[j]++;
580
2456
                    summer++;
581
                }
582
            }
583
641
        } while (freebits > summer);
584
    }
585
1311
    if (freebits < summer) {
586
20427
        for (i = 0; i < BANDS; i++) {
587
19808
            workT[i] = chctx->bitsBandT[i] ? (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] + 1.585)
588
19808
                                       : 1.e20;
589
        }
590
619
        if (stream_format_code & 0x2) {
591
546
            workT[0] = 1.e20;
592
546
            workT[1] = 1.e20;
593
546
            workT[2] = 1.e20;
594
546
            workT[3] = 1.e20;
595
        }
596
1290
        while (freebits < summer) {
597
671
            lowest   = 1.e10;
598
671
            low_indx = 0;
599
22143
            for (i = 0; i < BANDS; i++) {
600
21472
                if (workT[i] < lowest) {
601
3055
                    lowest   = workT[i];
602
3055
                    low_indx = i;
603
                }
604
            }
605
            // if (lowest >= 1.e10)
606
            //     break;
607
671
            workT[low_indx] = lowest + 2.0;
608
609
671
            if (!--chctx->bitsBandT[low_indx])
610
182
                workT[low_indx] = 1.e20;
611
612

3297
            for (j = band_tab[low_indx]; j < band_tab[low_indx+1] && (freebits < summer); j++) {
613
2626
                if (chctx->CWlengthT[j] > 0) {
614
2626
                    chctx->CWlengthT[j]--;
615
2626
                    summer--;
616
                }
617
            }
618
        }
619
    }
620
1311
    return 0;
621
}
622
623
1311
static void imc_get_skip_coeff(IMCContext *q, IMCChannel *chctx)
624
{
625
    int i, j;
626
627
1311
    memset(chctx->skipFlagBits,  0, sizeof(chctx->skipFlagBits));
628
1311
    memset(chctx->skipFlagCount, 0, sizeof(chctx->skipFlagCount));
629
43263
    for (i = 0; i < BANDS; i++) {
630

41952
        if (!chctx->bandFlagsBuf[i] || !chctx->bandWidthT[i])
631
33107
            continue;
632
633
8845
        if (!chctx->skipFlagRaw[i]) {
634
7667
            chctx->skipFlagBits[i] = band_tab[i + 1] - band_tab[i];
635
636
54698
            for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
637
47031
                chctx->skipFlags[j] = get_bits1(&q->gb);
638
47031
                if (chctx->skipFlags[j])
639
24764
                    chctx->skipFlagCount[i]++;
640
            }
641
        } else {
642
6648
            for (j = band_tab[i]; j < band_tab[i + 1] - 1; j += 2) {
643
5470
                if (!get_bits1(&q->gb)) { // 0
644
3869
                    chctx->skipFlagBits[i]++;
645
3869
                    chctx->skipFlags[j]      = 1;
646
3869
                    chctx->skipFlags[j + 1]  = 1;
647
3869
                    chctx->skipFlagCount[i] += 2;
648
                } else {
649
1601
                    if (get_bits1(&q->gb)) { // 11
650
899
                        chctx->skipFlagBits[i] += 2;
651
899
                        chctx->skipFlags[j]     = 0;
652
899
                        chctx->skipFlags[j + 1] = 1;
653
899
                        chctx->skipFlagCount[i]++;
654
                    } else {
655
702
                        chctx->skipFlagBits[i] += 3;
656
702
                        chctx->skipFlags[j + 1] = 0;
657
702
                        if (!get_bits1(&q->gb)) { // 100
658
466
                            chctx->skipFlags[j] = 1;
659
466
                            chctx->skipFlagCount[i]++;
660
                        } else { // 101
661
236
                            chctx->skipFlags[j] = 0;
662
                        }
663
                    }
664
                }
665
            }
666
667
1178
            if (j < band_tab[i + 1]) {
668
554
                chctx->skipFlagBits[i]++;
669
554
                if ((chctx->skipFlags[j] = get_bits1(&q->gb)))
670
357
                    chctx->skipFlagCount[i]++;
671
            }
672
        }
673
    }
674
1311
}
675
676
/**
677
 * Increase highest' band coefficient sizes as some bits won't be used
678
 */
679
1311
static void imc_adjust_bit_allocation(IMCContext *q, IMCChannel *chctx,
680
                                      int summer)
681
{
682
    float workT[32];
683
1311
    int corrected = 0;
684
    int i, j;
685
1311
    float highest  = 0;
686
1311
    int found_indx = 0;
687
688
43263
    for (i = 0; i < BANDS; i++) {
689
41952
        workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
690
41952
                                          : (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
691
    }
692
693
4778
    while (corrected < summer) {
694
3467
        if (highest <= -1.e20)
695
            break;
696
697
3467
        highest = -1.e20;
698
699
114411
        for (i = 0; i < BANDS; i++) {
700
110944
            if (workT[i] > highest) {
701
12956
                highest = workT[i];
702
12956
                found_indx = i;
703
            }
704
        }
705
706
3467
        if (highest > -1.e20) {
707
3467
            workT[found_indx] -= 2.0;
708
3467
            if (++(chctx->bitsBandT[found_indx]) == 6)
709
4
                workT[found_indx] = -1.e20;
710
711

26492
            for (j = band_tab[found_indx]; j < band_tab[found_indx+1] && (corrected < summer); j++) {
712

23025
                if (!chctx->skipFlags[j] && (chctx->CWlengthT[j] < 6)) {
713
19365
                    chctx->CWlengthT[j]++;
714
19365
                    corrected++;
715
                }
716
            }
717
        }
718
    }
719
1311
}
720
721
1311
static void imc_imdct256(IMCContext *q, IMCChannel *chctx, int channels)
722
{
723
    int i;
724
    float re, im;
725
1311
    float *dst1 = q->out_samples;
726
1311
    float *dst2 = q->out_samples + (COEFFS - 1);
727
728
    /* prerotation */
729
169119
    for (i = 0; i < COEFFS / 2; i++) {
730
167808
        q->samples[i].re = -(q->pre_coef1[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
731
167808
                            (q->pre_coef2[i] * chctx->CWdecoded[i * 2]);
732
167808
        q->samples[i].im =  (q->pre_coef2[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
733
167808
                            (q->pre_coef1[i] * chctx->CWdecoded[i * 2]);
734
    }
735
736
    /* FFT */
737
1311
    q->fft.fft_permute(&q->fft, q->samples);
738
1311
    q->fft.fft_calc(&q->fft, q->samples);
739
740
    /* postrotation, window and reorder */
741
169119
    for (i = 0; i < COEFFS / 2; i++) {
742
167808
        re = ( q->samples[i].re * q->post_cos[i]) + (-q->samples[i].im * q->post_sin[i]);
743
167808
        im = (-q->samples[i].im * q->post_cos[i]) - ( q->samples[i].re * q->post_sin[i]);
744
167808
        *dst1 =  (q->mdct_sine_window[COEFFS - 1 - i * 2] * chctx->last_fft_im[i])
745
167808
               + (q->mdct_sine_window[i * 2] * re);
746
167808
        *dst2 =  (q->mdct_sine_window[i * 2] * chctx->last_fft_im[i])
747
167808
               - (q->mdct_sine_window[COEFFS - 1 - i * 2] * re);
748
167808
        dst1 += 2;
749
167808
        dst2 -= 2;
750
167808
        chctx->last_fft_im[i] = im;
751
    }
752
1311
}
753
754
1311
static int inverse_quant_coeff(IMCContext *q, IMCChannel *chctx,
755
                               int stream_format_code)
756
{
757
    int i, j;
758
    int middle_value, cw_len, max_size;
759
    const float *quantizer;
760
761
43263
    for (i = 0; i < BANDS; i++) {
762
377568
        for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
763
335616
            chctx->CWdecoded[j] = 0;
764
335616
            cw_len = chctx->CWlengthT[j];
765
766

335616
            if (cw_len <= 0 || chctx->skipFlags[j])
767
114322
                continue;
768
769
221294
            max_size     = 1 << cw_len;
770
221294
            middle_value = max_size >> 1;
771
772

221294
            if (chctx->codewords[j] >= max_size || chctx->codewords[j] < 0)
773
                return AVERROR_INVALIDDATA;
774
775
221294
            if (cw_len >= 4) {
776
26835
                quantizer = imc_quantizer2[(stream_format_code & 2) >> 1];
777
26835
                if (chctx->codewords[j] >= middle_value)
778
13134
                    chctx->CWdecoded[j] =  quantizer[chctx->codewords[j] - 8]                * chctx->flcoeffs6[i];
779
                else
780
13701
                    chctx->CWdecoded[j] = -quantizer[max_size - chctx->codewords[j] - 8 - 1] * chctx->flcoeffs6[i];
781
            }else{
782
194459
                quantizer = imc_quantizer1[((stream_format_code & 2) >> 1) | (chctx->bandFlagsBuf[i] << 1)];
783
194459
                if (chctx->codewords[j] >= middle_value)
784
97287
                    chctx->CWdecoded[j] =  quantizer[chctx->codewords[j] - 1]            * chctx->flcoeffs6[i];
785
                else
786
97172
                    chctx->CWdecoded[j] = -quantizer[max_size - 2 - chctx->codewords[j]] * chctx->flcoeffs6[i];
787
            }
788
        }
789
    }
790
1311
    return 0;
791
}
792
793
794
1311
static void imc_get_coeffs(AVCodecContext *avctx,
795
                           IMCContext *q, IMCChannel *chctx)
796
{
797
    int i, j, cw_len, cw;
798
799
43263
    for (i = 0; i < BANDS; i++) {
800
41952
        if (!chctx->sumLenArr[i])
801
6759
            continue;
802

35193
        if (chctx->bandFlagsBuf[i] || chctx->bandWidthT[i]) {
803
292921
            for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
804
257728
                cw_len = chctx->CWlengthT[j];
805
257728
                cw = 0;
806
807

257728
                if (cw_len && (!chctx->bandFlagsBuf[i] || !chctx->skipFlags[j])) {
808
221294
                    if (get_bits_count(&q->gb) + cw_len > 512) {
809
                        av_log(avctx, AV_LOG_WARNING,
810
                            "Potential problem on band %i, coefficient %i"
811
                            ": cw_len=%i\n", i, j, cw_len);
812
                    } else
813
221294
                        cw = get_bits(&q->gb, cw_len);
814
                }
815
816
257728
                chctx->codewords[j] = cw;
817
            }
818
        }
819
    }
820
1311
}
821
822
1311
static void imc_refine_bit_allocation(IMCContext *q, IMCChannel *chctx)
823
{
824
    int i, j;
825
    int bits, summer;
826
827
43263
    for (i = 0; i < BANDS; i++) {
828
41952
        chctx->sumLenArr[i]   = 0;
829
41952
        chctx->skipFlagRaw[i] = 0;
830
377568
        for (j = band_tab[i]; j < band_tab[i + 1]; j++)
831
335616
            chctx->sumLenArr[i] += chctx->CWlengthT[j];
832
41952
        if (chctx->bandFlagsBuf[i])
833

8845
            if (((int)((band_tab[i + 1] - band_tab[i]) * 1.5) > chctx->sumLenArr[i]) && (chctx->sumLenArr[i] > 0))
834
1178
                chctx->skipFlagRaw[i] = 1;
835
    }
836
837
1311
    imc_get_skip_coeff(q, chctx);
838
839
43263
    for (i = 0; i < BANDS; i++) {
840
41952
        chctx->flcoeffs6[i] = chctx->flcoeffs1[i];
841
        /* band has flag set and at least one coded coefficient */
842

41952
        if (chctx->bandFlagsBuf[i] && (band_tab[i + 1] - band_tab[i]) != chctx->skipFlagCount[i]) {
843
8845
            chctx->flcoeffs6[i] *= q->sqrt_tab[ band_tab[i + 1] - band_tab[i]] /
844
8845
                                   q->sqrt_tab[(band_tab[i + 1] - band_tab[i] - chctx->skipFlagCount[i])];
845
        }
846
    }
847
848
    /* calculate bits left, bits needed and adjust bit allocation */
849
1311
    bits = summer = 0;
850
851
43263
    for (i = 0; i < BANDS; i++) {
852
41952
        if (chctx->bandFlagsBuf[i]) {
853
67370
            for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
854
58525
                if (chctx->skipFlags[j]) {
855
34224
                    summer += chctx->CWlengthT[j];
856
34224
                    chctx->CWlengthT[j] = 0;
857
                }
858
            }
859
8845
            bits   += chctx->skipFlagBits[i];
860
8845
            summer -= chctx->skipFlagBits[i];
861
        }
862
    }
863
1311
    imc_adjust_bit_allocation(q, chctx, summer);
864
1311
}
865
866
1311
static int imc_decode_block(AVCodecContext *avctx, IMCContext *q, int ch)
867
{
868
    int stream_format_code;
869
    int imc_hdr, i, j, ret;
870
    int flag;
871
    int bits;
872
    int counter, bitscount;
873
1311
    IMCChannel *chctx = q->chctx + ch;
874
875
876
    /* Check the frame header */
877
1311
    imc_hdr = get_bits(&q->gb, 9);
878
1311
    if (imc_hdr & 0x18) {
879
        av_log(avctx, AV_LOG_ERROR, "frame header check failed!\n");
880
        av_log(avctx, AV_LOG_ERROR, "got %X.\n", imc_hdr);
881
        return AVERROR_INVALIDDATA;
882
    }
883
1311
    stream_format_code = get_bits(&q->gb, 3);
884
885
1311
    if (stream_format_code & 0x04)
886
305
        chctx->decoder_reset = 1;
887
888
1311
    if (chctx->decoder_reset) {
889
10065
        for (i = 0; i < BANDS; i++)
890
9760
            chctx->old_floor[i] = 1.0;
891
78385
        for (i = 0; i < COEFFS; i++)
892
78080
            chctx->CWdecoded[i] = 0;
893
305
        chctx->decoder_reset = 0;
894
    }
895
896
1311
    flag = get_bits1(&q->gb);
897
1311
    if (stream_format_code & 0x1)
898
        imc_read_level_coeffs_raw(q, stream_format_code, chctx->levlCoeffBuf);
899
    else
900
1311
        imc_read_level_coeffs(q, stream_format_code, chctx->levlCoeffBuf);
901
902
1311
    if (stream_format_code & 0x1)
903
        imc_decode_level_coefficients_raw(q, chctx->levlCoeffBuf,
904
                                          chctx->flcoeffs1, chctx->flcoeffs2);
905
1311
    else if (stream_format_code & 0x4)
906
305
        imc_decode_level_coefficients(q, chctx->levlCoeffBuf,
907
305
                                      chctx->flcoeffs1, chctx->flcoeffs2);
908
    else
909
1006
        imc_decode_level_coefficients2(q, chctx->levlCoeffBuf, chctx->old_floor,
910
1006
                                       chctx->flcoeffs1, chctx->flcoeffs2);
911
912
43263
    for(i=0; i<BANDS; i++) {
913
41952
        if(chctx->flcoeffs1[i] > INT_MAX) {
914
            av_log(avctx, AV_LOG_ERROR, "scalefactor out of range\n");
915
            return AVERROR_INVALIDDATA;
916
        }
917
    }
918
919
1311
    memcpy(chctx->old_floor, chctx->flcoeffs1, 32 * sizeof(float));
920
921
1311
    counter = 0;
922
1311
    if (stream_format_code & 0x1) {
923
        for (i = 0; i < BANDS; i++) {
924
            chctx->bandWidthT[i]   = band_tab[i + 1] - band_tab[i];
925
            chctx->bandFlagsBuf[i] = 0;
926
            chctx->flcoeffs3[i]    = chctx->flcoeffs2[i] * 2;
927
            chctx->flcoeffs5[i]    = 1.0;
928
        }
929
    } else {
930
43263
        for (i = 0; i < BANDS; i++) {
931
41952
            if (chctx->levlCoeffBuf[i] == 16) {
932
4453
                chctx->bandWidthT[i] = 0;
933
4453
                counter++;
934
            } else
935
37499
                chctx->bandWidthT[i] = band_tab[i + 1] - band_tab[i];
936
        }
937
938
1311
        memset(chctx->bandFlagsBuf, 0, BANDS * sizeof(int));
939
41952
        for (i = 0; i < BANDS - 1; i++)
940
40641
            if (chctx->bandWidthT[i])
941
37481
                chctx->bandFlagsBuf[i] = get_bits1(&q->gb);
942
943
1311
        imc_calculate_coeffs(q, chctx->flcoeffs1, chctx->flcoeffs2,
944
1311
                             chctx->bandWidthT, chctx->flcoeffs3,
945
1311
                             chctx->flcoeffs5);
946
    }
947
948
1311
    bitscount = 0;
949
    /* first 4 bands will be assigned 5 bits per coefficient */
950
1311
    if (stream_format_code & 0x2) {
951
1179
        bitscount += 15;
952
953
1179
        chctx->bitsBandT[0] = 5;
954
1179
        chctx->CWlengthT[0] = 5;
955
1179
        chctx->CWlengthT[1] = 5;
956
1179
        chctx->CWlengthT[2] = 5;
957
4716
        for (i = 1; i < 4; i++) {
958
3537
            if (stream_format_code & 0x1)
959
                bits = 5;
960
            else
961
3537
                bits = (chctx->levlCoeffBuf[i] == 16) ? 0 : 5;
962
3537
            chctx->bitsBandT[i] = bits;
963
14148
            for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
964
10611
                chctx->CWlengthT[j] = bits;
965
10611
                bitscount      += bits;
966
            }
967
        }
968
    }
969
1311
    if (avctx->codec_id == AV_CODEC_ID_IAC) {
970
        bitscount += !!chctx->bandWidthT[BANDS - 1];
971
        if (!(stream_format_code & 0x2))
972
            bitscount += 16;
973
    }
974
975
1311
    if ((ret = bit_allocation(q, chctx, stream_format_code,
976
1311
                              512 - bitscount - get_bits_count(&q->gb),
977
                              flag)) < 0) {
978
        av_log(avctx, AV_LOG_ERROR, "Bit allocations failed\n");
979
        chctx->decoder_reset = 1;
980
        return ret;
981
    }
982
983
1311
    if (stream_format_code & 0x1) {
984
        for (i = 0; i < BANDS; i++)
985
            chctx->skipFlags[i] = 0;
986
    } else {
987
1311
        imc_refine_bit_allocation(q, chctx);
988
    }
989
990
43263
    for (i = 0; i < BANDS; i++) {
991
41952
        chctx->sumLenArr[i] = 0;
992
993
377568
        for (j = band_tab[i]; j < band_tab[i + 1]; j++)
994
335616
            if (!chctx->skipFlags[j])
995
301392
                chctx->sumLenArr[i] += chctx->CWlengthT[j];
996
    }
997
998
1311
    memset(chctx->codewords, 0, sizeof(chctx->codewords));
999
1000
1311
    imc_get_coeffs(avctx, q, chctx);
1001
1002
1311
    if (inverse_quant_coeff(q, chctx, stream_format_code) < 0) {
1003
        av_log(avctx, AV_LOG_ERROR, "Inverse quantization of coefficients failed\n");
1004
        chctx->decoder_reset = 1;
1005
        return AVERROR_INVALIDDATA;
1006
    }
1007
1008
1311
    memset(chctx->skipFlags, 0, sizeof(chctx->skipFlags));
1009
1010
1311
    imc_imdct256(q, chctx, avctx->channels);
1011
1012
1311
    return 0;
1013
}
1014
1015
1311
static int imc_decode_frame(AVCodecContext *avctx, void *data,
1016
                            int *got_frame_ptr, AVPacket *avpkt)
1017
{
1018
1311
    AVFrame *frame     = data;
1019
1311
    const uint8_t *buf = avpkt->data;
1020
1311
    int buf_size = avpkt->size;
1021
    int ret, i;
1022
1023
1311
    IMCContext *q = avctx->priv_data;
1024
1025
1311
    LOCAL_ALIGNED_16(uint16_t, buf16, [(IMC_BLOCK_SIZE + AV_INPUT_BUFFER_PADDING_SIZE) / 2]);
1026
1027
1311
    q->avctx = avctx;
1028
1029
1311
    if (buf_size < IMC_BLOCK_SIZE * avctx->channels) {
1030
        av_log(avctx, AV_LOG_ERROR, "frame too small!\n");
1031
        return AVERROR_INVALIDDATA;
1032
    }
1033
1034
    /* get output buffer */
1035
1311
    frame->nb_samples = COEFFS;
1036
1311
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1037
        return ret;
1038
1039
2622
    for (i = 0; i < avctx->channels; i++) {
1040
1311
        q->out_samples = (float *)frame->extended_data[i];
1041
1042
1311
        q->bdsp.bswap16_buf(buf16, (const uint16_t *) buf, IMC_BLOCK_SIZE / 2);
1043
1044
1311
        init_get_bits(&q->gb, (const uint8_t*)buf16, IMC_BLOCK_SIZE * 8);
1045
1046
1311
        buf += IMC_BLOCK_SIZE;
1047
1048
1311
        if ((ret = imc_decode_block(avctx, q, i)) < 0)
1049
            return ret;
1050
    }
1051
1052
1311
    if (avctx->channels == 2) {
1053
        q->fdsp->butterflies_float((float *)frame->extended_data[0],
1054
                                  (float *)frame->extended_data[1], COEFFS);
1055
    }
1056
1057
1311
    *got_frame_ptr = 1;
1058
1059
1311
    return IMC_BLOCK_SIZE * avctx->channels;
1060
}
1061
1062
2
static av_cold int imc_decode_close(AVCodecContext * avctx)
1063
{
1064
2
    IMCContext *q = avctx->priv_data;
1065
1066
2
    ff_fft_end(&q->fft);
1067
2
    av_freep(&q->fdsp);
1068
1069
2
    return 0;
1070
}
1071
1072
static av_cold void flush(AVCodecContext *avctx)
1073
{
1074
    IMCContext *q = avctx->priv_data;
1075
1076
    q->chctx[0].decoder_reset =
1077
    q->chctx[1].decoder_reset = 1;
1078
}
1079
1080
#if CONFIG_IMC_DECODER
1081
AVCodec ff_imc_decoder = {
1082
    .name           = "imc",
1083
    .long_name      = NULL_IF_CONFIG_SMALL("IMC (Intel Music Coder)"),
1084
    .type           = AVMEDIA_TYPE_AUDIO,
1085
    .id             = AV_CODEC_ID_IMC,
1086
    .priv_data_size = sizeof(IMCContext),
1087
    .init           = imc_decode_init,
1088
    .close          = imc_decode_close,
1089
    .decode         = imc_decode_frame,
1090
    .flush          = flush,
1091
    .capabilities   = AV_CODEC_CAP_DR1,
1092
    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1093
                                                      AV_SAMPLE_FMT_NONE },
1094
};
1095
#endif
1096
#if CONFIG_IAC_DECODER
1097
AVCodec ff_iac_decoder = {
1098
    .name           = "iac",
1099
    .long_name      = NULL_IF_CONFIG_SMALL("IAC (Indeo Audio Coder)"),
1100
    .type           = AVMEDIA_TYPE_AUDIO,
1101
    .id             = AV_CODEC_ID_IAC,
1102
    .priv_data_size = sizeof(IMCContext),
1103
    .init           = imc_decode_init,
1104
    .close          = imc_decode_close,
1105
    .decode         = imc_decode_frame,
1106
    .flush          = flush,
1107
    .capabilities   = AV_CODEC_CAP_DR1,
1108
    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1109
                                                      AV_SAMPLE_FMT_NONE },
1110
};
1111
#endif