Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / imc.c
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
34 #include <math.h>
35 #include <stddef.h>
36 #include <stdio.h>
37
38 #include "libavutil/channel_layout.h"
39 #include "libavutil/float_dsp.h"
40 #include "libavutil/internal.h"
41 #include "libavutil/libm.h"
42 #include "avcodec.h"
43 #include "bswapdsp.h"
44 #include "get_bits.h"
45 #include "fft.h"
46 #include "internal.h"
47 #include "sinewin.h"
48
49 #include "imcdata.h"
50
51 #define IMC_BLOCK_SIZE 64
52 #define IMC_FRAME_ID 0x21
53 #define BANDS 32
54 #define COEFFS 256
55
56 typedef struct IMCChannel {
57 float old_floor[BANDS];
58 float flcoeffs1[BANDS];
59 float flcoeffs2[BANDS];
60 float flcoeffs3[BANDS];
61 float flcoeffs4[BANDS];
62 float flcoeffs5[BANDS];
63 float flcoeffs6[BANDS];
64 float CWdecoded[COEFFS];
65
66 int bandWidthT[BANDS]; ///< codewords per band
67 int bitsBandT[BANDS]; ///< how many bits per codeword in band
68 int CWlengthT[COEFFS]; ///< how many bits in each codeword
69 int levlCoeffBuf[BANDS];
70 int bandFlagsBuf[BANDS]; ///< flags for each band
71 int sumLenArr[BANDS]; ///< bits for all coeffs in band
72 int skipFlagRaw[BANDS]; ///< skip flags are stored in raw form or not
73 int skipFlagBits[BANDS]; ///< bits used to code skip flags
74 int skipFlagCount[BANDS]; ///< skipped coeffients per band
75 int skipFlags[COEFFS]; ///< skip coefficient decoding or not
76 int codewords[COEFFS]; ///< raw codewords read from bitstream
77
78 float last_fft_im[COEFFS];
79
80 int decoder_reset;
81 } IMCChannel;
82
83 typedef struct {
84 IMCChannel chctx[2];
85
86 /** MDCT tables */
87 //@{
88 float mdct_sine_window[COEFFS];
89 float post_cos[COEFFS];
90 float post_sin[COEFFS];
91 float pre_coef1[COEFFS];
92 float pre_coef2[COEFFS];
93 //@}
94
95 float sqrt_tab[30];
96 GetBitContext gb;
97
98 BswapDSPContext bdsp;
99 AVFloatDSPContext *fdsp;
100 FFTContext fft;
101 DECLARE_ALIGNED(32, FFTComplex, samples)[COEFFS / 2];
102 float *out_samples;
103
104 int coef0_pos;
105
106 int8_t cyclTab[32], cyclTab2[32];
107 float weights1[31], weights2[31];
108 } IMCContext;
109
110 static VLC huffman_vlc[4][4];
111
112 #define VLC_TABLES_SIZE 9512
113
114 static const int vlc_offsets[17] = {
115 0, 640, 1156, 1732, 2308, 2852, 3396, 3924,
116 4452, 5220, 5860, 6628, 7268, 7908, 8424, 8936, VLC_TABLES_SIZE
117 };
118
119 static VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2];
120
121 static inline double freq2bark(double freq)
122 {
123 return 3.5 * atan((freq / 7500.0) * (freq / 7500.0)) + 13.0 * atan(freq * 0.00076);
124 }
125
126 static av_cold void iac_generate_tabs(IMCContext *q, int sampling_rate)
127 {
128 double freqmin[32], freqmid[32], freqmax[32];
129 double scale = sampling_rate / (256.0 * 2.0 * 2.0);
130 double nyquist_freq = sampling_rate * 0.5;
131 double freq, bark, prev_bark = 0, tf, tb;
132 int i, j;
133
134 for (i = 0; i < 32; i++) {
135 freq = (band_tab[i] + band_tab[i + 1] - 1) * scale;
136 bark = freq2bark(freq);
137
138 if (i > 0) {
139 tb = bark - prev_bark;
140 q->weights1[i - 1] = pow(10.0, -1.0 * tb);
141 q->weights2[i - 1] = pow(10.0, -2.7 * tb);
142 }
143 prev_bark = bark;
144
145 freqmid[i] = freq;
146
147 tf = freq;
148 while (tf < nyquist_freq) {
149 tf += 0.5;
150 tb = freq2bark(tf);
151 if (tb > bark + 0.5)
152 break;
153 }
154 freqmax[i] = tf;
155
156 tf = freq;
157 while (tf > 0.0) {
158 tf -= 0.5;
159 tb = freq2bark(tf);
160 if (tb <= bark - 0.5)
161 break;
162 }
163 freqmin[i] = tf;
164 }
165
166 for (i = 0; i < 32; i++) {
167 freq = freqmax[i];
168 for (j = 31; j > 0 && freq <= freqmid[j]; j--);
169 q->cyclTab[i] = j + 1;
170
171 freq = freqmin[i];
172 for (j = 0; j < 32 && freq >= freqmid[j]; j++);
173 q->cyclTab2[i] = j - 1;
174 }
175 }
176
177 static av_cold int imc_decode_init(AVCodecContext *avctx)
178 {
179 int i, j, ret;
180 IMCContext *q = avctx->priv_data;
181 double r1, r2;
182
183 if (avctx->codec_id == AV_CODEC_ID_IAC && avctx->sample_rate > 96000) {
184 av_log(avctx, AV_LOG_ERROR,
185 "Strange sample rate of %i, file likely corrupt or "
186 "needing a new table derivation method.\n",
187 avctx->sample_rate);
188 return AVERROR_PATCHWELCOME;
189 }
190
191 if (avctx->codec_id == AV_CODEC_ID_IMC)
192 avctx->channels = 1;
193
194 if (avctx->channels > 2) {
195 avpriv_request_sample(avctx, "Number of channels > 2");
196 return AVERROR_PATCHWELCOME;
197 }
198
199 for (j = 0; j < avctx->channels; j++) {
200 q->chctx[j].decoder_reset = 1;
201
202 for (i = 0; i < BANDS; i++)
203 q->chctx[j].old_floor[i] = 1.0;
204
205 for (i = 0; i < COEFFS / 2; i++)
206 q->chctx[j].last_fft_im[i] = 0;
207 }
208
209 /* Build mdct window, a simple sine window normalized with sqrt(2) */
210 ff_sine_window_init(q->mdct_sine_window, COEFFS);
211 for (i = 0; i < COEFFS; i++)
212 q->mdct_sine_window[i] *= sqrt(2.0);
213 for (i = 0; i < COEFFS / 2; i++) {
214 q->post_cos[i] = (1.0f / 32768) * cos(i / 256.0 * M_PI);
215 q->post_sin[i] = (1.0f / 32768) * sin(i / 256.0 * M_PI);
216
217 r1 = sin((i * 4.0 + 1.0) / 1024.0 * M_PI);
218 r2 = cos((i * 4.0 + 1.0) / 1024.0 * M_PI);
219
220 if (i & 0x1) {
221 q->pre_coef1[i] = (r1 + r2) * sqrt(2.0);
222 q->pre_coef2[i] = -(r1 - r2) * sqrt(2.0);
223 } else {
224 q->pre_coef1[i] = -(r1 + r2) * sqrt(2.0);
225 q->pre_coef2[i] = (r1 - r2) * sqrt(2.0);
226 }
227 }
228
229 /* Generate a square root table */
230
231 for (i = 0; i < 30; i++)
232 q->sqrt_tab[i] = sqrt(i);
233
234 /* initialize the VLC tables */
235 for (i = 0; i < 4 ; i++) {
236 for (j = 0; j < 4; j++) {
237 huffman_vlc[i][j].table = &vlc_tables[vlc_offsets[i * 4 + j]];
238 huffman_vlc[i][j].table_allocated = vlc_offsets[i * 4 + j + 1] - vlc_offsets[i * 4 + j];
239 init_vlc(&huffman_vlc[i][j], 9, imc_huffman_sizes[i],
240 imc_huffman_lens[i][j], 1, 1,
241 imc_huffman_bits[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC);
242 }
243 }
244
245 if (avctx->codec_id == AV_CODEC_ID_IAC) {
246 iac_generate_tabs(q, avctx->sample_rate);
247 } else {
248 memcpy(q->cyclTab, cyclTab, sizeof(cyclTab));
249 memcpy(q->cyclTab2, cyclTab2, sizeof(cyclTab2));
250 memcpy(q->weights1, imc_weights1, sizeof(imc_weights1));
251 memcpy(q->weights2, imc_weights2, sizeof(imc_weights2));
252 }
253
254 if ((ret = ff_fft_init(&q->fft, 7, 1))) {
255 av_log(avctx, AV_LOG_INFO, "FFT init failed\n");
256 return ret;
257 }
258 ff_bswapdsp_init(&q->bdsp);
259 q->fdsp = avpriv_float_dsp_alloc(avctx->flags & CODEC_FLAG_BITEXACT);
260 if (!q->fdsp) {
261 ff_fft_end(&q->fft);
262
263 return AVERROR(ENOMEM);
264 }
265
266 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
267 avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO
268 : AV_CH_LAYOUT_STEREO;
269
270 return 0;
271 }
272
273 static void imc_calculate_coeffs(IMCContext *q, float *flcoeffs1,
274 float *flcoeffs2, int *bandWidthT,
275 float *flcoeffs3, float *flcoeffs5)
276 {
277 float workT1[BANDS];
278 float workT2[BANDS];
279 float workT3[BANDS];
280 float snr_limit = 1.e-30;
281 float accum = 0.0;
282 int i, cnt2;
283
284 for (i = 0; i < BANDS; i++) {
285 flcoeffs5[i] = workT2[i] = 0.0;
286 if (bandWidthT[i]) {
287 workT1[i] = flcoeffs1[i] * flcoeffs1[i];
288 flcoeffs3[i] = 2.0 * flcoeffs2[i];
289 } else {
290 workT1[i] = 0.0;
291 flcoeffs3[i] = -30000.0;
292 }
293 workT3[i] = bandWidthT[i] * workT1[i] * 0.01;
294 if (workT3[i] <= snr_limit)
295 workT3[i] = 0.0;
296 }
297
298 for (i = 0; i < BANDS; i++) {
299 for (cnt2 = i; cnt2 < q->cyclTab[i]; cnt2++)
300 flcoeffs5[cnt2] = flcoeffs5[cnt2] + workT3[i];
301 workT2[cnt2 - 1] = workT2[cnt2 - 1] + workT3[i];
302 }
303
304 for (i = 1; i < BANDS; i++) {
305 accum = (workT2[i - 1] + accum) * q->weights1[i - 1];
306 flcoeffs5[i] += accum;
307 }
308
309 for (i = 0; i < BANDS; i++)
310 workT2[i] = 0.0;
311
312 for (i = 0; i < BANDS; i++) {
313 for (cnt2 = i - 1; cnt2 > q->cyclTab2[i]; cnt2--)
314 flcoeffs5[cnt2] += workT3[i];
315 workT2[cnt2+1] += workT3[i];
316 }
317
318 accum = 0.0;
319
320 for (i = BANDS-2; i >= 0; i--) {
321 accum = (workT2[i+1] + accum) * q->weights2[i];
322 flcoeffs5[i] += accum;
323 // there is missing code here, but it seems to never be triggered
324 }
325 }
326
327
328 static void imc_read_level_coeffs(IMCContext *q, int stream_format_code,
329 int *levlCoeffs)
330 {
331 int i;
332 VLC *hufftab[4];
333 int start = 0;
334 const uint8_t *cb_sel;
335 int s;
336
337 s = stream_format_code >> 1;
338 hufftab[0] = &huffman_vlc[s][0];
339 hufftab[1] = &huffman_vlc[s][1];
340 hufftab[2] = &huffman_vlc[s][2];
341 hufftab[3] = &huffman_vlc[s][3];
342 cb_sel = imc_cb_select[s];
343
344 if (stream_format_code & 4)
345 start = 1;
346 if (start)
347 levlCoeffs[0] = get_bits(&q->gb, 7);
348 for (i = start; i < BANDS; i++) {
349 levlCoeffs[i] = get_vlc2(&q->gb, hufftab[cb_sel[i]]->table,
350 hufftab[cb_sel[i]]->bits, 2);
351 if (levlCoeffs[i] == 17)
352 levlCoeffs[i] += get_bits(&q->gb, 4);
353 }
354 }
355
356 static void imc_read_level_coeffs_raw(IMCContext *q, int stream_format_code,
357 int *levlCoeffs)
358 {
359 int i;
360
361 q->coef0_pos = get_bits(&q->gb, 5);
362 levlCoeffs[0] = get_bits(&q->gb, 7);
363 for (i = 1; i < BANDS; i++)
364 levlCoeffs[i] = get_bits(&q->gb, 4);
365 }
366
367 static void imc_decode_level_coefficients(IMCContext *q, int *levlCoeffBuf,
368 float *flcoeffs1, float *flcoeffs2)
369 {
370 int i, level;
371 float tmp, tmp2;
372 // maybe some frequency division thingy
373
374 flcoeffs1[0] = 20000.0 / exp2 (levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
375 flcoeffs2[0] = log2f(flcoeffs1[0]);
376 tmp = flcoeffs1[0];
377 tmp2 = flcoeffs2[0];
378
379 for (i = 1; i < BANDS; i++) {
380 level = levlCoeffBuf[i];
381 if (level == 16) {
382 flcoeffs1[i] = 1.0;
383 flcoeffs2[i] = 0.0;
384 } else {
385 if (level < 17)
386 level -= 7;
387 else if (level <= 24)
388 level -= 32;
389 else
390 level -= 16;
391
392 tmp *= imc_exp_tab[15 + level];
393 tmp2 += 0.83048 * level; // 0.83048 = log2(10) * 0.25
394 flcoeffs1[i] = tmp;
395 flcoeffs2[i] = tmp2;
396 }
397 }
398 }
399
400
401 static void imc_decode_level_coefficients2(IMCContext *q, int *levlCoeffBuf,
402 float *old_floor, float *flcoeffs1,
403 float *flcoeffs2)
404 {
405 int i;
406 /* FIXME maybe flag_buf = noise coding and flcoeffs1 = new scale factors
407 * and flcoeffs2 old scale factors
408 * might be incomplete due to a missing table that is in the binary code
409 */
410 for (i = 0; i < BANDS; i++) {
411 flcoeffs1[i] = 0;
412 if (levlCoeffBuf[i] < 16) {
413 flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i];
414 flcoeffs2[i] = (levlCoeffBuf[i] - 7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25
415 } else {
416 flcoeffs1[i] = old_floor[i];
417 }
418 }
419 }
420
421 static void imc_decode_level_coefficients_raw(IMCContext *q, int *levlCoeffBuf,
422 float *flcoeffs1, float *flcoeffs2)
423 {
424 int i, level, pos;
425 float tmp, tmp2;
426
427 pos = q->coef0_pos;
428 flcoeffs1[pos] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
429 flcoeffs2[pos] = log2f(flcoeffs1[0]);
430 tmp = flcoeffs1[pos];
431 tmp2 = flcoeffs2[pos];
432
433 levlCoeffBuf++;
434 for (i = 0; i < BANDS; i++) {
435 if (i == pos)
436 continue;
437 level = *levlCoeffBuf++;
438 flcoeffs1[i] = tmp * powf(10.0, -level * 0.4375); //todo tab
439 flcoeffs2[i] = tmp2 - 1.4533435415 * level; // 1.4533435415 = log2(10) * 0.4375
440 }
441 }
442
443 /**
444 * Perform bit allocation depending on bits available
445 */
446 static int bit_allocation(IMCContext *q, IMCChannel *chctx,
447 int stream_format_code, int freebits, int flag)
448 {
449 int i, j;
450 const float limit = -1.e20;
451 float highest = 0.0;
452 int indx;
453 int t1 = 0;
454 int t2 = 1;
455 float summa = 0.0;
456 int iacc = 0;
457 int summer = 0;
458 int rres, cwlen;
459 float lowest = 1.e10;
460 int low_indx = 0;
461 float workT[32];
462 int flg;
463 int found_indx = 0;
464
465 for (i = 0; i < BANDS; i++)
466 highest = FFMAX(highest, chctx->flcoeffs1[i]);
467
468 for (i = 0; i < BANDS - 1; i++) {
469 if (chctx->flcoeffs5[i] <= 0) {
470 av_log(NULL, AV_LOG_ERROR, "flcoeffs5 %f invalid\n", chctx->flcoeffs5[i]);
471 return AVERROR_INVALIDDATA;
472 }
473 chctx->flcoeffs4[i] = chctx->flcoeffs3[i] - log2f(chctx->flcoeffs5[i]);
474 }
475 chctx->flcoeffs4[BANDS - 1] = limit;
476
477 highest = highest * 0.25;
478
479 for (i = 0; i < BANDS; i++) {
480 indx = -1;
481 if ((band_tab[i + 1] - band_tab[i]) == chctx->bandWidthT[i])
482 indx = 0;
483
484 if ((band_tab[i + 1] - band_tab[i]) > chctx->bandWidthT[i])
485 indx = 1;
486
487 if (((band_tab[i + 1] - band_tab[i]) / 2) >= chctx->bandWidthT[i])
488 indx = 2;
489
490 if (indx == -1)
491 return AVERROR_INVALIDDATA;
492
493 chctx->flcoeffs4[i] += xTab[(indx * 2 + (chctx->flcoeffs1[i] < highest)) * 2 + flag];
494 }
495
496 if (stream_format_code & 0x2) {
497 chctx->flcoeffs4[0] = limit;
498 chctx->flcoeffs4[1] = limit;
499 chctx->flcoeffs4[2] = limit;
500 chctx->flcoeffs4[3] = limit;
501 }
502
503 for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS - 1; i++) {
504 iacc += chctx->bandWidthT[i];
505 summa += chctx->bandWidthT[i] * chctx->flcoeffs4[i];
506 }
507
508 if (!iacc)
509 return AVERROR_INVALIDDATA;
510
511 chctx->bandWidthT[BANDS - 1] = 0;
512 summa = (summa * 0.5 - freebits) / iacc;
513
514
515 for (i = 0; i < BANDS / 2; i++) {
516 rres = summer - freebits;
517 if ((rres >= -8) && (rres <= 8))
518 break;
519
520 summer = 0;
521 iacc = 0;
522
523 for (j = (stream_format_code & 0x2) ? 4 : 0; j < BANDS; j++) {
524 cwlen = av_clipf(((chctx->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6);
525
526 chctx->bitsBandT[j] = cwlen;
527 summer += chctx->bandWidthT[j] * cwlen;
528
529 if (cwlen > 0)
530 iacc += chctx->bandWidthT[j];
531 }
532
533 flg = t2;
534 t2 = 1;
535 if (freebits < summer)
536 t2 = -1;
537 if (i == 0)
538 flg = t2;
539 if (flg != t2)
540 t1++;
541
542 summa = (float)(summer - freebits) / ((t1 + 1) * iacc) + summa;
543 }
544
545 for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS; i++) {
546 for (j = band_tab[i]; j < band_tab[i + 1]; j++)
547 chctx->CWlengthT[j] = chctx->bitsBandT[i];
548 }
549
550 if (freebits > summer) {
551 for (i = 0; i < BANDS; i++) {
552 workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
553 : (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
554 }
555
556 highest = 0.0;
557
558 do {
559 if (highest <= -1.e20)
560 break;
561
562 found_indx = 0;
563 highest = -1.e20;
564
565 for (i = 0; i < BANDS; i++) {
566 if (workT[i] > highest) {
567 highest = workT[i];
568 found_indx = i;
569 }
570 }
571
572 if (highest > -1.e20) {
573 workT[found_indx] -= 2.0;
574 if (++chctx->bitsBandT[found_indx] == 6)
575 workT[found_indx] = -1.e20;
576
577 for (j = band_tab[found_indx]; j < band_tab[found_indx + 1] && (freebits > summer); j++) {
578 chctx->CWlengthT[j]++;
579 summer++;
580 }
581 }
582 } while (freebits > summer);
583 }
584 if (freebits < summer) {
585 for (i = 0; i < BANDS; i++) {
586 workT[i] = chctx->bitsBandT[i] ? (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] + 1.585)
587 : 1.e20;
588 }
589 if (stream_format_code & 0x2) {
590 workT[0] = 1.e20;
591 workT[1] = 1.e20;
592 workT[2] = 1.e20;
593 workT[3] = 1.e20;
594 }
595 while (freebits < summer) {
596 lowest = 1.e10;
597 low_indx = 0;
598 for (i = 0; i < BANDS; i++) {
599 if (workT[i] < lowest) {
600 lowest = workT[i];
601 low_indx = i;
602 }
603 }
604 // if (lowest >= 1.e10)
605 // break;
606 workT[low_indx] = lowest + 2.0;
607
608 if (!--chctx->bitsBandT[low_indx])
609 workT[low_indx] = 1.e20;
610
611 for (j = band_tab[low_indx]; j < band_tab[low_indx+1] && (freebits < summer); j++) {
612 if (chctx->CWlengthT[j] > 0) {
613 chctx->CWlengthT[j]--;
614 summer--;
615 }
616 }
617 }
618 }
619 return 0;
620 }
621
622 static void imc_get_skip_coeff(IMCContext *q, IMCChannel *chctx)
623 {
624 int i, j;
625
626 memset(chctx->skipFlagBits, 0, sizeof(chctx->skipFlagBits));
627 memset(chctx->skipFlagCount, 0, sizeof(chctx->skipFlagCount));
628 for (i = 0; i < BANDS; i++) {
629 if (!chctx->bandFlagsBuf[i] || !chctx->bandWidthT[i])
630 continue;
631
632 if (!chctx->skipFlagRaw[i]) {
633 chctx->skipFlagBits[i] = band_tab[i + 1] - band_tab[i];
634
635 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
636 chctx->skipFlags[j] = get_bits1(&q->gb);
637 if (chctx->skipFlags[j])
638 chctx->skipFlagCount[i]++;
639 }
640 } else {
641 for (j = band_tab[i]; j < band_tab[i + 1] - 1; j += 2) {
642 if (!get_bits1(&q->gb)) { // 0
643 chctx->skipFlagBits[i]++;
644 chctx->skipFlags[j] = 1;
645 chctx->skipFlags[j + 1] = 1;
646 chctx->skipFlagCount[i] += 2;
647 } else {
648 if (get_bits1(&q->gb)) { // 11
649 chctx->skipFlagBits[i] += 2;
650 chctx->skipFlags[j] = 0;
651 chctx->skipFlags[j + 1] = 1;
652 chctx->skipFlagCount[i]++;
653 } else {
654 chctx->skipFlagBits[i] += 3;
655 chctx->skipFlags[j + 1] = 0;
656 if (!get_bits1(&q->gb)) { // 100
657 chctx->skipFlags[j] = 1;
658 chctx->skipFlagCount[i]++;
659 } else { // 101
660 chctx->skipFlags[j] = 0;
661 }
662 }
663 }
664 }
665
666 if (j < band_tab[i + 1]) {
667 chctx->skipFlagBits[i]++;
668 if ((chctx->skipFlags[j] = get_bits1(&q->gb)))
669 chctx->skipFlagCount[i]++;
670 }
671 }
672 }
673 }
674
675 /**
676 * Increase highest' band coefficient sizes as some bits won't be used
677 */
678 static void imc_adjust_bit_allocation(IMCContext *q, IMCChannel *chctx,
679 int summer)
680 {
681 float workT[32];
682 int corrected = 0;
683 int i, j;
684 float highest = 0;
685 int found_indx = 0;
686
687 for (i = 0; i < BANDS; i++) {
688 workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
689 : (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
690 }
691
692 while (corrected < summer) {
693 if (highest <= -1.e20)
694 break;
695
696 highest = -1.e20;
697
698 for (i = 0; i < BANDS; i++) {
699 if (workT[i] > highest) {
700 highest = workT[i];
701 found_indx = i;
702 }
703 }
704
705 if (highest > -1.e20) {
706 workT[found_indx] -= 2.0;
707 if (++(chctx->bitsBandT[found_indx]) == 6)
708 workT[found_indx] = -1.e20;
709
710 for (j = band_tab[found_indx]; j < band_tab[found_indx+1] && (corrected < summer); j++) {
711 if (!chctx->skipFlags[j] && (chctx->CWlengthT[j] < 6)) {
712 chctx->CWlengthT[j]++;
713 corrected++;
714 }
715 }
716 }
717 }
718 }
719
720 static void imc_imdct256(IMCContext *q, IMCChannel *chctx, int channels)
721 {
722 int i;
723 float re, im;
724 float *dst1 = q->out_samples;
725 float *dst2 = q->out_samples + (COEFFS - 1);
726
727 /* prerotation */
728 for (i = 0; i < COEFFS / 2; i++) {
729 q->samples[i].re = -(q->pre_coef1[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
730 (q->pre_coef2[i] * chctx->CWdecoded[i * 2]);
731 q->samples[i].im = (q->pre_coef2[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
732 (q->pre_coef1[i] * chctx->CWdecoded[i * 2]);
733 }
734
735 /* FFT */
736 q->fft.fft_permute(&q->fft, q->samples);
737 q->fft.fft_calc(&q->fft, q->samples);
738
739 /* postrotation, window and reorder */
740 for (i = 0; i < COEFFS / 2; i++) {
741 re = ( q->samples[i].re * q->post_cos[i]) + (-q->samples[i].im * q->post_sin[i]);
742 im = (-q->samples[i].im * q->post_cos[i]) - ( q->samples[i].re * q->post_sin[i]);
743 *dst1 = (q->mdct_sine_window[COEFFS - 1 - i * 2] * chctx->last_fft_im[i])
744 + (q->mdct_sine_window[i * 2] * re);
745 *dst2 = (q->mdct_sine_window[i * 2] * chctx->last_fft_im[i])
746 - (q->mdct_sine_window[COEFFS - 1 - i * 2] * re);
747 dst1 += 2;
748 dst2 -= 2;
749 chctx->last_fft_im[i] = im;
750 }
751 }
752
753 static int inverse_quant_coeff(IMCContext *q, IMCChannel *chctx,
754 int stream_format_code)
755 {
756 int i, j;
757 int middle_value, cw_len, max_size;
758 const float *quantizer;
759
760 for (i = 0; i < BANDS; i++) {
761 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
762 chctx->CWdecoded[j] = 0;
763 cw_len = chctx->CWlengthT[j];
764
765 if (cw_len <= 0 || chctx->skipFlags[j])
766 continue;
767
768 max_size = 1 << cw_len;
769 middle_value = max_size >> 1;
770
771 if (chctx->codewords[j] >= max_size || chctx->codewords[j] < 0)
772 return AVERROR_INVALIDDATA;
773
774 if (cw_len >= 4) {
775 quantizer = imc_quantizer2[(stream_format_code & 2) >> 1];
776 if (chctx->codewords[j] >= middle_value)
777 chctx->CWdecoded[j] = quantizer[chctx->codewords[j] - 8] * chctx->flcoeffs6[i];
778 else
779 chctx->CWdecoded[j] = -quantizer[max_size - chctx->codewords[j] - 8 - 1] * chctx->flcoeffs6[i];
780 }else{
781 quantizer = imc_quantizer1[((stream_format_code & 2) >> 1) | (chctx->bandFlagsBuf[i] << 1)];
782 if (chctx->codewords[j] >= middle_value)
783 chctx->CWdecoded[j] = quantizer[chctx->codewords[j] - 1] * chctx->flcoeffs6[i];
784 else
785 chctx->CWdecoded[j] = -quantizer[max_size - 2 - chctx->codewords[j]] * chctx->flcoeffs6[i];
786 }
787 }
788 }
789 return 0;
790 }
791
792
793 static int imc_get_coeffs(IMCContext *q, IMCChannel *chctx)
794 {
795 int i, j, cw_len, cw;
796
797 for (i = 0; i < BANDS; i++) {
798 if (!chctx->sumLenArr[i])
799 continue;
800 if (chctx->bandFlagsBuf[i] || chctx->bandWidthT[i]) {
801 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
802 cw_len = chctx->CWlengthT[j];
803 cw = 0;
804
805 if (get_bits_count(&q->gb) + cw_len > 512) {
806 av_dlog(NULL, "Band %i coeff %i cw_len %i\n", i, j, cw_len);
807 return AVERROR_INVALIDDATA;
808 }
809
810 if (cw_len && (!chctx->bandFlagsBuf[i] || !chctx->skipFlags[j]))
811 cw = get_bits(&q->gb, cw_len);
812
813 chctx->codewords[j] = cw;
814 }
815 }
816 }
817 return 0;
818 }
819
820 static void imc_refine_bit_allocation(IMCContext *q, IMCChannel *chctx)
821 {
822 int i, j;
823 int bits, summer;
824
825 for (i = 0; i < BANDS; i++) {
826 chctx->sumLenArr[i] = 0;
827 chctx->skipFlagRaw[i] = 0;
828 for (j = band_tab[i]; j < band_tab[i + 1]; j++)
829 chctx->sumLenArr[i] += chctx->CWlengthT[j];
830 if (chctx->bandFlagsBuf[i])
831 if ((((band_tab[i + 1] - band_tab[i]) * 1.5) > chctx->sumLenArr[i]) && (chctx->sumLenArr[i] > 0))
832 chctx->skipFlagRaw[i] = 1;
833 }
834
835 imc_get_skip_coeff(q, chctx);
836
837 for (i = 0; i < BANDS; i++) {
838 chctx->flcoeffs6[i] = chctx->flcoeffs1[i];
839 /* band has flag set and at least one coded coefficient */
840 if (chctx->bandFlagsBuf[i] && (band_tab[i + 1] - band_tab[i]) != chctx->skipFlagCount[i]) {
841 chctx->flcoeffs6[i] *= q->sqrt_tab[ band_tab[i + 1] - band_tab[i]] /
842 q->sqrt_tab[(band_tab[i + 1] - band_tab[i] - chctx->skipFlagCount[i])];
843 }
844 }
845
846 /* calculate bits left, bits needed and adjust bit allocation */
847 bits = summer = 0;
848
849 for (i = 0; i < BANDS; i++) {
850 if (chctx->bandFlagsBuf[i]) {
851 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
852 if (chctx->skipFlags[j]) {
853 summer += chctx->CWlengthT[j];
854 chctx->CWlengthT[j] = 0;
855 }
856 }
857 bits += chctx->skipFlagBits[i];
858 summer -= chctx->skipFlagBits[i];
859 }
860 }
861 imc_adjust_bit_allocation(q, chctx, summer);
862 }
863
864 static int imc_decode_block(AVCodecContext *avctx, IMCContext *q, int ch)
865 {
866 int stream_format_code;
867 int imc_hdr, i, j, ret;
868 int flag;
869 int bits;
870 int counter, bitscount;
871 IMCChannel *chctx = q->chctx + ch;
872
873
874 /* Check the frame header */
875 imc_hdr = get_bits(&q->gb, 9);
876 if (imc_hdr & 0x18) {
877 av_log(avctx, AV_LOG_ERROR, "frame header check failed!\n");
878 av_log(avctx, AV_LOG_ERROR, "got %X.\n", imc_hdr);
879 return AVERROR_INVALIDDATA;
880 }
881 stream_format_code = get_bits(&q->gb, 3);
882
883 if (stream_format_code & 0x04)
884 chctx->decoder_reset = 1;
885
886 if (chctx->decoder_reset) {
887 for (i = 0; i < BANDS; i++)
888 chctx->old_floor[i] = 1.0;
889 for (i = 0; i < COEFFS; i++)
890 chctx->CWdecoded[i] = 0;
891 chctx->decoder_reset = 0;
892 }
893
894 flag = get_bits1(&q->gb);
895 if (stream_format_code & 0x1)
896 imc_read_level_coeffs_raw(q, stream_format_code, chctx->levlCoeffBuf);
897 else
898 imc_read_level_coeffs(q, stream_format_code, chctx->levlCoeffBuf);
899
900 if (stream_format_code & 0x1)
901 imc_decode_level_coefficients_raw(q, chctx->levlCoeffBuf,
902 chctx->flcoeffs1, chctx->flcoeffs2);
903 else if (stream_format_code & 0x4)
904 imc_decode_level_coefficients(q, chctx->levlCoeffBuf,
905 chctx->flcoeffs1, chctx->flcoeffs2);
906 else
907 imc_decode_level_coefficients2(q, chctx->levlCoeffBuf, chctx->old_floor,
908 chctx->flcoeffs1, chctx->flcoeffs2);
909
910 for(i=0; i<BANDS; i++) {
911 if(chctx->flcoeffs1[i] > INT_MAX) {
912 av_log(avctx, AV_LOG_ERROR, "scalefactor out of range\n");
913 return AVERROR_INVALIDDATA;
914 }
915 }
916
917 memcpy(chctx->old_floor, chctx->flcoeffs1, 32 * sizeof(float));
918
919 counter = 0;
920 if (stream_format_code & 0x1) {
921 for (i = 0; i < BANDS; i++) {
922 chctx->bandWidthT[i] = band_tab[i + 1] - band_tab[i];
923 chctx->bandFlagsBuf[i] = 0;
924 chctx->flcoeffs3[i] = chctx->flcoeffs2[i] * 2;
925 chctx->flcoeffs5[i] = 1.0;
926 }
927 } else {
928 for (i = 0; i < BANDS; i++) {
929 if (chctx->levlCoeffBuf[i] == 16) {
930 chctx->bandWidthT[i] = 0;
931 counter++;
932 } else
933 chctx->bandWidthT[i] = band_tab[i + 1] - band_tab[i];
934 }
935
936 memset(chctx->bandFlagsBuf, 0, BANDS * sizeof(int));
937 for (i = 0; i < BANDS - 1; i++)
938 if (chctx->bandWidthT[i])
939 chctx->bandFlagsBuf[i] = get_bits1(&q->gb);
940
941 imc_calculate_coeffs(q, chctx->flcoeffs1, chctx->flcoeffs2,
942 chctx->bandWidthT, chctx->flcoeffs3,
943 chctx->flcoeffs5);
944 }
945
946 bitscount = 0;
947 /* first 4 bands will be assigned 5 bits per coefficient */
948 if (stream_format_code & 0x2) {
949 bitscount += 15;
950
951 chctx->bitsBandT[0] = 5;
952 chctx->CWlengthT[0] = 5;
953 chctx->CWlengthT[1] = 5;
954 chctx->CWlengthT[2] = 5;
955 for (i = 1; i < 4; i++) {
956 if (stream_format_code & 0x1)
957 bits = 5;
958 else
959 bits = (chctx->levlCoeffBuf[i] == 16) ? 0 : 5;
960 chctx->bitsBandT[i] = bits;
961 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
962 chctx->CWlengthT[j] = bits;
963 bitscount += bits;
964 }
965 }
966 }
967 if (avctx->codec_id == AV_CODEC_ID_IAC) {
968 bitscount += !!chctx->bandWidthT[BANDS - 1];
969 if (!(stream_format_code & 0x2))
970 bitscount += 16;
971 }
972
973 if ((ret = bit_allocation(q, chctx, stream_format_code,
974 512 - bitscount - get_bits_count(&q->gb),
975 flag)) < 0) {
976 av_log(avctx, AV_LOG_ERROR, "Bit allocations failed\n");
977 chctx->decoder_reset = 1;
978 return ret;
979 }
980
981 if (stream_format_code & 0x1) {
982 for (i = 0; i < BANDS; i++)
983 chctx->skipFlags[i] = 0;
984 } else {
985 imc_refine_bit_allocation(q, chctx);
986 }
987
988 for (i = 0; i < BANDS; i++) {
989 chctx->sumLenArr[i] = 0;
990
991 for (j = band_tab[i]; j < band_tab[i + 1]; j++)
992 if (!chctx->skipFlags[j])
993 chctx->sumLenArr[i] += chctx->CWlengthT[j];
994 }
995
996 memset(chctx->codewords, 0, sizeof(chctx->codewords));
997
998 if (imc_get_coeffs(q, chctx) < 0) {
999 av_log(avctx, AV_LOG_ERROR, "Read coefficients failed\n");
1000 chctx->decoder_reset = 1;
1001 return AVERROR_INVALIDDATA;
1002 }
1003
1004 if (inverse_quant_coeff(q, chctx, stream_format_code) < 0) {
1005 av_log(avctx, AV_LOG_ERROR, "Inverse quantization of coefficients failed\n");
1006 chctx->decoder_reset = 1;
1007 return AVERROR_INVALIDDATA;
1008 }
1009
1010 memset(chctx->skipFlags, 0, sizeof(chctx->skipFlags));
1011
1012 imc_imdct256(q, chctx, avctx->channels);
1013
1014 return 0;
1015 }
1016
1017 static int imc_decode_frame(AVCodecContext *avctx, void *data,
1018 int *got_frame_ptr, AVPacket *avpkt)
1019 {
1020 AVFrame *frame = data;
1021 const uint8_t *buf = avpkt->data;
1022 int buf_size = avpkt->size;
1023 int ret, i;
1024
1025 IMCContext *q = avctx->priv_data;
1026
1027 LOCAL_ALIGNED_16(uint16_t, buf16, [IMC_BLOCK_SIZE / 2 + FF_INPUT_BUFFER_PADDING_SIZE/2]);
1028
1029 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 frame->nb_samples = COEFFS;
1036 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1037 return ret;
1038
1039 for (i = 0; i < avctx->channels; i++) {
1040 q->out_samples = (float *)frame->extended_data[i];
1041
1042 q->bdsp.bswap16_buf(buf16, (const uint16_t *) buf, IMC_BLOCK_SIZE / 2);
1043
1044 init_get_bits(&q->gb, (const uint8_t*)buf16, IMC_BLOCK_SIZE * 8);
1045
1046 buf += IMC_BLOCK_SIZE;
1047
1048 if ((ret = imc_decode_block(avctx, q, i)) < 0)
1049 return ret;
1050 }
1051
1052 if (avctx->channels == 2) {
1053 q->fdsp->butterflies_float((float *)frame->extended_data[0],
1054 (float *)frame->extended_data[1], COEFFS);
1055 }
1056
1057 *got_frame_ptr = 1;
1058
1059 return IMC_BLOCK_SIZE * avctx->channels;
1060 }
1061
1062 static av_cold int imc_decode_close(AVCodecContext * avctx)
1063 {
1064 IMCContext *q = avctx->priv_data;
1065
1066 ff_fft_end(&q->fft);
1067 av_freep(&q->fdsp);
1068
1069 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 = 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 = CODEC_CAP_DR1,
1108 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1109 AV_SAMPLE_FMT_NONE },
1110 };
1111 #endif