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Imported Debian version 2.4.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / imc.c
CommitLineData
2ba45a60
DM		 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
56typedef 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
83typedef 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
110static VLC huffman_vlc[4][4];
111
112#define VLC_TABLES_SIZE 9512
113
114static 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
119static VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2];
120
121static 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
126static 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
177static 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 avpriv_float_dsp_init(&q->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
260 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
261 avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO
262 : AV_CH_LAYOUT_STEREO;
263
264 return 0;
265}
266
267static void imc_calculate_coeffs(IMCContext *q, float *flcoeffs1,
268 float *flcoeffs2, int *bandWidthT,
269 float *flcoeffs3, float *flcoeffs5)
270{
271 float workT1[BANDS];
272 float workT2[BANDS];
273 float workT3[BANDS];
274 float snr_limit = 1.e-30;
275 float accum = 0.0;
276 int i, cnt2;
277
278 for (i = 0; i < BANDS; i++) {
279 flcoeffs5[i] = workT2[i] = 0.0;
280 if (bandWidthT[i]) {
281 workT1[i] = flcoeffs1[i] * flcoeffs1[i];
282 flcoeffs3[i] = 2.0 * flcoeffs2[i];
283 } else {
284 workT1[i] = 0.0;
285 flcoeffs3[i] = -30000.0;
286 }
287 workT3[i] = bandWidthT[i] * workT1[i] * 0.01;
288 if (workT3[i] <= snr_limit)
289 workT3[i] = 0.0;
290 }
291
292 for (i = 0; i < BANDS; i++) {
293 for (cnt2 = i; cnt2 < q->cyclTab[i]; cnt2++)
294 flcoeffs5[cnt2] = flcoeffs5[cnt2] + workT3[i];
295 workT2[cnt2 - 1] = workT2[cnt2 - 1] + workT3[i];
296 }
297
298 for (i = 1; i < BANDS; i++) {
299 accum = (workT2[i - 1] + accum) * q->weights1[i - 1];
300 flcoeffs5[i] += accum;
301 }
302
303 for (i = 0; i < BANDS; i++)
304 workT2[i] = 0.0;
305
306 for (i = 0; i < BANDS; i++) {
307 for (cnt2 = i - 1; cnt2 > q->cyclTab2[i]; cnt2--)
308 flcoeffs5[cnt2] += workT3[i];
309 workT2[cnt2+1] += workT3[i];
310 }
311
312 accum = 0.0;
313
314 for (i = BANDS-2; i >= 0; i--) {
315 accum = (workT2[i+1] + accum) * q->weights2[i];
316 flcoeffs5[i] += accum;
317 // there is missing code here, but it seems to never be triggered
318 }
319}
320
321
322static void imc_read_level_coeffs(IMCContext *q, int stream_format_code,
323 int *levlCoeffs)
324{
325 int i;
326 VLC *hufftab[4];
327 int start = 0;
328 const uint8_t *cb_sel;
329 int s;
330
331 s = stream_format_code >> 1;
332 hufftab[0] = &huffman_vlc[s][0];
333 hufftab[1] = &huffman_vlc[s][1];
334 hufftab[2] = &huffman_vlc[s][2];
335 hufftab[3] = &huffman_vlc[s][3];
336 cb_sel = imc_cb_select[s];
337
338 if (stream_format_code & 4)
339 start = 1;
340 if (start)
341 levlCoeffs[0] = get_bits(&q->gb, 7);
342 for (i = start; i < BANDS; i++) {
343 levlCoeffs[i] = get_vlc2(&q->gb, hufftab[cb_sel[i]]->table,
344 hufftab[cb_sel[i]]->bits, 2);
345 if (levlCoeffs[i] == 17)
346 levlCoeffs[i] += get_bits(&q->gb, 4);
347 }
348}
349
350static void imc_read_level_coeffs_raw(IMCContext *q, int stream_format_code,
351 int *levlCoeffs)
352{
353 int i;
354
355 q->coef0_pos = get_bits(&q->gb, 5);
356 levlCoeffs[0] = get_bits(&q->gb, 7);
357 for (i = 1; i < BANDS; i++)
358 levlCoeffs[i] = get_bits(&q->gb, 4);
359}
360
361static void imc_decode_level_coefficients(IMCContext *q, int *levlCoeffBuf,
362 float *flcoeffs1, float *flcoeffs2)
363{
364 int i, level;
365 float tmp, tmp2;
366 // maybe some frequency division thingy
367
368 flcoeffs1[0] = 20000.0 / exp2 (levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
369 flcoeffs2[0] = log2f(flcoeffs1[0]);
370 tmp = flcoeffs1[0];
371 tmp2 = flcoeffs2[0];
372
373 for (i = 1; i < BANDS; i++) {
374 level = levlCoeffBuf[i];
375 if (level == 16) {
376 flcoeffs1[i] = 1.0;
377 flcoeffs2[i] = 0.0;
378 } else {
379 if (level < 17)
380 level -= 7;
381 else if (level <= 24)
382 level -= 32;
383 else
384 level -= 16;
385
386 tmp *= imc_exp_tab[15 + level];
387 tmp2 += 0.83048 * level; // 0.83048 = log2(10) * 0.25
388 flcoeffs1[i] = tmp;
389 flcoeffs2[i] = tmp2;
390 }
391 }
392}
393
394
395static void imc_decode_level_coefficients2(IMCContext *q, int *levlCoeffBuf,
396 float *old_floor, float *flcoeffs1,
397 float *flcoeffs2)
398{
399 int i;
400 /* FIXME maybe flag_buf = noise coding and flcoeffs1 = new scale factors
401 * and flcoeffs2 old scale factors
402 * might be incomplete due to a missing table that is in the binary code
403 */
404 for (i = 0; i < BANDS; i++) {
405 flcoeffs1[i] = 0;
406 if (levlCoeffBuf[i] < 16) {
407 flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i];
408 flcoeffs2[i] = (levlCoeffBuf[i] - 7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25
409 } else {
410 flcoeffs1[i] = old_floor[i];
411 }
412 }
413}
414
415static void imc_decode_level_coefficients_raw(IMCContext *q, int *levlCoeffBuf,
416 float *flcoeffs1, float *flcoeffs2)
417{
418 int i, level, pos;
419 float tmp, tmp2;
420
421 pos = q->coef0_pos;
422 flcoeffs1[pos] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
423 flcoeffs2[pos] = log2f(flcoeffs1[0]);
424 tmp = flcoeffs1[pos];
425 tmp2 = flcoeffs2[pos];
426
427 levlCoeffBuf++;
428 for (i = 0; i < BANDS; i++) {
429 if (i == pos)
430 continue;
431 level = *levlCoeffBuf++;
432 flcoeffs1[i] = tmp * powf(10.0, -level * 0.4375); //todo tab
433 flcoeffs2[i] = tmp2 - 1.4533435415 * level; // 1.4533435415 = log2(10) * 0.4375
434 }
435}
436
437/**
438 * Perform bit allocation depending on bits available
439 */
440static int bit_allocation(IMCContext *q, IMCChannel *chctx,
441 int stream_format_code, int freebits, int flag)
442{
443 int i, j;
444 const float limit = -1.e20;
445 float highest = 0.0;
446 int indx;
447 int t1 = 0;
448 int t2 = 1;
449 float summa = 0.0;
450 int iacc = 0;
451 int summer = 0;
452 int rres, cwlen;
453 float lowest = 1.e10;
454 int low_indx = 0;
455 float workT[32];
456 int flg;
457 int found_indx = 0;
458
459 for (i = 0; i < BANDS; i++)
460 highest = FFMAX(highest, chctx->flcoeffs1[i]);
461
462 for (i = 0; i < BANDS - 1; i++) {
463 if (chctx->flcoeffs5[i] <= 0) {
464 av_log(NULL, AV_LOG_ERROR, "flcoeffs5 %f invalid\n", chctx->flcoeffs5[i]);
465 return AVERROR_INVALIDDATA;
466 }
467 chctx->flcoeffs4[i] = chctx->flcoeffs3[i] - log2f(chctx->flcoeffs5[i]);
468 }
469 chctx->flcoeffs4[BANDS - 1] = limit;
470
471 highest = highest * 0.25;
472
473 for (i = 0; i < BANDS; i++) {
474 indx = -1;
475 if ((band_tab[i + 1] - band_tab[i]) == chctx->bandWidthT[i])
476 indx = 0;
477
478 if ((band_tab[i + 1] - band_tab[i]) > chctx->bandWidthT[i])
479 indx = 1;
480
481 if (((band_tab[i + 1] - band_tab[i]) / 2) >= chctx->bandWidthT[i])
482 indx = 2;
483
484 if (indx == -1)
485 return AVERROR_INVALIDDATA;
486
487 chctx->flcoeffs4[i] += xTab[(indx * 2 + (chctx->flcoeffs1[i] < highest)) * 2 + flag];
488 }
489
490 if (stream_format_code & 0x2) {
491 chctx->flcoeffs4[0] = limit;
492 chctx->flcoeffs4[1] = limit;
493 chctx->flcoeffs4[2] = limit;
494 chctx->flcoeffs4[3] = limit;
495 }
496
497 for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS - 1; i++) {
498 iacc += chctx->bandWidthT[i];
499 summa += chctx->bandWidthT[i] * chctx->flcoeffs4[i];
500 }
501
502 if (!iacc)
503 return AVERROR_INVALIDDATA;
504
505 chctx->bandWidthT[BANDS - 1] = 0;
506 summa = (summa * 0.5 - freebits) / iacc;
507
508
509 for (i = 0; i < BANDS / 2; i++) {
510 rres = summer - freebits;
511 if ((rres >= -8) && (rres <= 8))
512 break;
513
514 summer = 0;
515 iacc = 0;
516
517 for (j = (stream_format_code & 0x2) ? 4 : 0; j < BANDS; j++) {
518 cwlen = av_clipf(((chctx->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6);
519
520 chctx->bitsBandT[j] = cwlen;
521 summer += chctx->bandWidthT[j] * cwlen;
522
523 if (cwlen > 0)
524 iacc += chctx->bandWidthT[j];
525 }
526
527 flg = t2;
528 t2 = 1;
529 if (freebits < summer)
530 t2 = -1;
531 if (i == 0)
532 flg = t2;
533 if (flg != t2)
534 t1++;
535
536 summa = (float)(summer - freebits) / ((t1 + 1) * iacc) + summa;
537 }
538
539 for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS; i++) {
540 for (j = band_tab[i]; j < band_tab[i + 1]; j++)
541 chctx->CWlengthT[j] = chctx->bitsBandT[i];
542 }
543
544 if (freebits > summer) {
545 for (i = 0; i < BANDS; i++) {
546 workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
547 : (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
548 }
549
550 highest = 0.0;
551
552 do {
553 if (highest <= -1.e20)
554 break;
555
556 found_indx = 0;
557 highest = -1.e20;
558
559 for (i = 0; i < BANDS; i++) {
560 if (workT[i] > highest) {
561 highest = workT[i];
562 found_indx = i;
563 }
564 }
565
566 if (highest > -1.e20) {
567 workT[found_indx] -= 2.0;
568 if (++chctx->bitsBandT[found_indx] == 6)
569 workT[found_indx] = -1.e20;
570
571 for (j = band_tab[found_indx]; j < band_tab[found_indx + 1] && (freebits > summer); j++) {
572 chctx->CWlengthT[j]++;
573 summer++;
574 }
575 }
576 } while (freebits > summer);
577 }
578 if (freebits < summer) {
579 for (i = 0; i < BANDS; i++) {
580 workT[i] = chctx->bitsBandT[i] ? (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] + 1.585)
581 : 1.e20;
582 }
583 if (stream_format_code & 0x2) {
584 workT[0] = 1.e20;
585 workT[1] = 1.e20;
586 workT[2] = 1.e20;
587 workT[3] = 1.e20;
588 }
589 while (freebits < summer) {
590 lowest = 1.e10;
591 low_indx = 0;
592 for (i = 0; i < BANDS; i++) {
593 if (workT[i] < lowest) {
594 lowest = workT[i];
595 low_indx = i;
596 }
597 }
598 // if (lowest >= 1.e10)
599 // break;
600 workT[low_indx] = lowest + 2.0;
601
602 if (!--chctx->bitsBandT[low_indx])
603 workT[low_indx] = 1.e20;
604
605 for (j = band_tab[low_indx]; j < band_tab[low_indx+1] && (freebits < summer); j++) {
606 if (chctx->CWlengthT[j] > 0) {
607 chctx->CWlengthT[j]--;
608 summer--;
609 }
610 }
611 }
612 }
613 return 0;
614}
615
616static void imc_get_skip_coeff(IMCContext *q, IMCChannel *chctx)
617{
618 int i, j;
619
620 memset(chctx->skipFlagBits, 0, sizeof(chctx->skipFlagBits));
621 memset(chctx->skipFlagCount, 0, sizeof(chctx->skipFlagCount));
622 for (i = 0; i < BANDS; i++) {
623 if (!chctx->bandFlagsBuf[i] || !chctx->bandWidthT[i])
624 continue;
625
626 if (!chctx->skipFlagRaw[i]) {
627 chctx->skipFlagBits[i] = band_tab[i + 1] - band_tab[i];
628
629 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
630 chctx->skipFlags[j] = get_bits1(&q->gb);
631 if (chctx->skipFlags[j])
632 chctx->skipFlagCount[i]++;
633 }
634 } else {
635 for (j = band_tab[i]; j < band_tab[i + 1] - 1; j += 2) {
636 if (!get_bits1(&q->gb)) { // 0
637 chctx->skipFlagBits[i]++;
638 chctx->skipFlags[j] = 1;
639 chctx->skipFlags[j + 1] = 1;
640 chctx->skipFlagCount[i] += 2;
641 } else {
642 if (get_bits1(&q->gb)) { // 11
643 chctx->skipFlagBits[i] += 2;
644 chctx->skipFlags[j] = 0;
645 chctx->skipFlags[j + 1] = 1;
646 chctx->skipFlagCount[i]++;
647 } else {
648 chctx->skipFlagBits[i] += 3;
649 chctx->skipFlags[j + 1] = 0;
650 if (!get_bits1(&q->gb)) { // 100
651 chctx->skipFlags[j] = 1;
652 chctx->skipFlagCount[i]++;
653 } else { // 101
654 chctx->skipFlags[j] = 0;
655 }
656 }
657 }
658 }
659
660 if (j < band_tab[i + 1]) {
661 chctx->skipFlagBits[i]++;
662 if ((chctx->skipFlags[j] = get_bits1(&q->gb)))
663 chctx->skipFlagCount[i]++;
664 }
665 }
666 }
667}
668
669/**
670 * Increase highest' band coefficient sizes as some bits won't be used
671 */
672static void imc_adjust_bit_allocation(IMCContext *q, IMCChannel *chctx,
673 int summer)
674{
675 float workT[32];
676 int corrected = 0;
677 int i, j;
678 float highest = 0;
679 int found_indx = 0;
680
681 for (i = 0; i < BANDS; i++) {
682 workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
683 : (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
684 }
685
686 while (corrected < summer) {
687 if (highest <= -1.e20)
688 break;
689
690 highest = -1.e20;
691
692 for (i = 0; i < BANDS; i++) {
693 if (workT[i] > highest) {
694 highest = workT[i];
695 found_indx = i;
696 }
697 }
698
699 if (highest > -1.e20) {
700 workT[found_indx] -= 2.0;
701 if (++(chctx->bitsBandT[found_indx]) == 6)
702 workT[found_indx] = -1.e20;
703
704 for (j = band_tab[found_indx]; j < band_tab[found_indx+1] && (corrected < summer); j++) {
705 if (!chctx->skipFlags[j] && (chctx->CWlengthT[j] < 6)) {
706 chctx->CWlengthT[j]++;
707 corrected++;
708 }
709 }
710 }
711 }
712}
713
714static void imc_imdct256(IMCContext *q, IMCChannel *chctx, int channels)
715{
716 int i;
717 float re, im;
718 float *dst1 = q->out_samples;
719 float *dst2 = q->out_samples + (COEFFS - 1);
720
721 /* prerotation */
722 for (i = 0; i < COEFFS / 2; i++) {
723 q->samples[i].re = -(q->pre_coef1[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
724 (q->pre_coef2[i] * chctx->CWdecoded[i * 2]);
725 q->samples[i].im = (q->pre_coef2[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
726 (q->pre_coef1[i] * chctx->CWdecoded[i * 2]);
727 }
728
729 /* FFT */
730 q->fft.fft_permute(&q->fft, q->samples);
731 q->fft.fft_calc(&q->fft, q->samples);
732
733 /* postrotation, window and reorder */
734 for (i = 0; i < COEFFS / 2; i++) {
735 re = ( q->samples[i].re * q->post_cos[i]) + (-q->samples[i].im * q->post_sin[i]);
736 im = (-q->samples[i].im * q->post_cos[i]) - ( q->samples[i].re * q->post_sin[i]);
737 *dst1 = (q->mdct_sine_window[COEFFS - 1 - i * 2] * chctx->last_fft_im[i])
738 + (q->mdct_sine_window[i * 2] * re);
739 *dst2 = (q->mdct_sine_window[i * 2] * chctx->last_fft_im[i])
740 - (q->mdct_sine_window[COEFFS - 1 - i * 2] * re);
741 dst1 += 2;
742 dst2 -= 2;
743 chctx->last_fft_im[i] = im;
744 }
745}
746
747static int inverse_quant_coeff(IMCContext *q, IMCChannel *chctx,
748 int stream_format_code)
749{
750 int i, j;
751 int middle_value, cw_len, max_size;
752 const float *quantizer;
753
754 for (i = 0; i < BANDS; i++) {
755 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
756 chctx->CWdecoded[j] = 0;
757 cw_len = chctx->CWlengthT[j];
758
759 if (cw_len <= 0 || chctx->skipFlags[j])
760 continue;
761
762 max_size = 1 << cw_len;
763 middle_value = max_size >> 1;
764
765 if (chctx->codewords[j] >= max_size || chctx->codewords[j] < 0)
766 return AVERROR_INVALIDDATA;
767
768 if (cw_len >= 4) {
769 quantizer = imc_quantizer2[(stream_format_code & 2) >> 1];
770 if (chctx->codewords[j] >= middle_value)
771 chctx->CWdecoded[j] = quantizer[chctx->codewords[j] - 8] * chctx->flcoeffs6[i];
772 else
773 chctx->CWdecoded[j] = -quantizer[max_size - chctx->codewords[j] - 8 - 1] * chctx->flcoeffs6[i];
774 }else{
775 quantizer = imc_quantizer1[((stream_format_code & 2) >> 1) | (chctx->bandFlagsBuf[i] << 1)];
776 if (chctx->codewords[j] >= middle_value)
777 chctx->CWdecoded[j] = quantizer[chctx->codewords[j] - 1] * chctx->flcoeffs6[i];
778 else
779 chctx->CWdecoded[j] = -quantizer[max_size - 2 - chctx->codewords[j]] * chctx->flcoeffs6[i];
780 }
781 }
782 }
783 return 0;
784}
785
786
787static int imc_get_coeffs(IMCContext *q, IMCChannel *chctx)
788{
789 int i, j, cw_len, cw;
790
791 for (i = 0; i < BANDS; i++) {
792 if (!chctx->sumLenArr[i])
793 continue;
794 if (chctx->bandFlagsBuf[i] || chctx->bandWidthT[i]) {
795 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
796 cw_len = chctx->CWlengthT[j];
797 cw = 0;
798
799 if (get_bits_count(&q->gb) + cw_len > 512) {
800 av_dlog(NULL, "Band %i coeff %i cw_len %i\n", i, j, cw_len);
801 return AVERROR_INVALIDDATA;
802 }
803
804 if (cw_len && (!chctx->bandFlagsBuf[i] || !chctx->skipFlags[j]))
805 cw = get_bits(&q->gb, cw_len);
806
807 chctx->codewords[j] = cw;
808 }
809 }
810 }
811 return 0;
812}
813
814static void imc_refine_bit_allocation(IMCContext *q, IMCChannel *chctx)
815{
816 int i, j;
817 int bits, summer;
818
819 for (i = 0; i < BANDS; i++) {
820 chctx->sumLenArr[i] = 0;
821 chctx->skipFlagRaw[i] = 0;
822 for (j = band_tab[i]; j < band_tab[i + 1]; j++)
823 chctx->sumLenArr[i] += chctx->CWlengthT[j];
824 if (chctx->bandFlagsBuf[i])
825 if ((((band_tab[i + 1] - band_tab[i]) * 1.5) > chctx->sumLenArr[i]) && (chctx->sumLenArr[i] > 0))
826 chctx->skipFlagRaw[i] = 1;
827 }
828
829 imc_get_skip_coeff(q, chctx);
830
831 for (i = 0; i < BANDS; i++) {
832 chctx->flcoeffs6[i] = chctx->flcoeffs1[i];
833 /* band has flag set and at least one coded coefficient */
834 if (chctx->bandFlagsBuf[i] && (band_tab[i + 1] - band_tab[i]) != chctx->skipFlagCount[i]) {
835 chctx->flcoeffs6[i] *= q->sqrt_tab[ band_tab[i + 1] - band_tab[i]] /
836 q->sqrt_tab[(band_tab[i + 1] - band_tab[i] - chctx->skipFlagCount[i])];
837 }
838 }
839
840 /* calculate bits left, bits needed and adjust bit allocation */
841 bits = summer = 0;
842
843 for (i = 0; i < BANDS; i++) {
844 if (chctx->bandFlagsBuf[i]) {
845 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
846 if (chctx->skipFlags[j]) {
847 summer += chctx->CWlengthT[j];
848 chctx->CWlengthT[j] = 0;
849 }
850 }
851 bits += chctx->skipFlagBits[i];
852 summer -= chctx->skipFlagBits[i];
853 }
854 }
855 imc_adjust_bit_allocation(q, chctx, summer);
856}
857
858static int imc_decode_block(AVCodecContext *avctx, IMCContext *q, int ch)
859{
860 int stream_format_code;
861 int imc_hdr, i, j, ret;
862 int flag;
863 int bits;
864 int counter, bitscount;
865 IMCChannel *chctx = q->chctx + ch;
866
867
868 /* Check the frame header */
869 imc_hdr = get_bits(&q->gb, 9);
870 if (imc_hdr & 0x18) {
871 av_log(avctx, AV_LOG_ERROR, "frame header check failed!\n");
872 av_log(avctx, AV_LOG_ERROR, "got %X.\n", imc_hdr);
873 return AVERROR_INVALIDDATA;
874 }
875 stream_format_code = get_bits(&q->gb, 3);
876
877 if (stream_format_code & 0x04)
878 chctx->decoder_reset = 1;
879
880 if (chctx->decoder_reset) {
881 for (i = 0; i < BANDS; i++)
882 chctx->old_floor[i] = 1.0;
883 for (i = 0; i < COEFFS; i++)
884 chctx->CWdecoded[i] = 0;
885 chctx->decoder_reset = 0;
886 }
887
888 flag = get_bits1(&q->gb);
889 if (stream_format_code & 0x1)
890 imc_read_level_coeffs_raw(q, stream_format_code, chctx->levlCoeffBuf);
891 else
892 imc_read_level_coeffs(q, stream_format_code, chctx->levlCoeffBuf);
893
894 if (stream_format_code & 0x1)
895 imc_decode_level_coefficients_raw(q, chctx->levlCoeffBuf,
896 chctx->flcoeffs1, chctx->flcoeffs2);
897 else if (stream_format_code & 0x4)
898 imc_decode_level_coefficients(q, chctx->levlCoeffBuf,
899 chctx->flcoeffs1, chctx->flcoeffs2);
900 else
901 imc_decode_level_coefficients2(q, chctx->levlCoeffBuf, chctx->old_floor,
902 chctx->flcoeffs1, chctx->flcoeffs2);
903
904 for(i=0; i<BANDS; i++) {
905 if(chctx->flcoeffs1[i] > INT_MAX) {
906 av_log(avctx, AV_LOG_ERROR, "scalefactor out of range\n");
907 return AVERROR_INVALIDDATA;
908 }
909 }
910
911 memcpy(chctx->old_floor, chctx->flcoeffs1, 32 * sizeof(float));
912
913 counter = 0;
914 if (stream_format_code & 0x1) {
915 for (i = 0; i < BANDS; i++) {
916 chctx->bandWidthT[i] = band_tab[i + 1] - band_tab[i];
917 chctx->bandFlagsBuf[i] = 0;
918 chctx->flcoeffs3[i] = chctx->flcoeffs2[i] * 2;
919 chctx->flcoeffs5[i] = 1.0;
920 }
921 } else {
922 for (i = 0; i < BANDS; i++) {
923 if (chctx->levlCoeffBuf[i] == 16) {
924 chctx->bandWidthT[i] = 0;
925 counter++;
926 } else
927 chctx->bandWidthT[i] = band_tab[i + 1] - band_tab[i];
928 }
929
930 memset(chctx->bandFlagsBuf, 0, BANDS * sizeof(int));
931 for (i = 0; i < BANDS - 1; i++)
932 if (chctx->bandWidthT[i])
933 chctx->bandFlagsBuf[i] = get_bits1(&q->gb);
934
935 imc_calculate_coeffs(q, chctx->flcoeffs1, chctx->flcoeffs2,
936 chctx->bandWidthT, chctx->flcoeffs3,
937 chctx->flcoeffs5);
938 }
939
940 bitscount = 0;
941 /* first 4 bands will be assigned 5 bits per coefficient */
942 if (stream_format_code & 0x2) {
943 bitscount += 15;
944
945 chctx->bitsBandT[0] = 5;
946 chctx->CWlengthT[0] = 5;
947 chctx->CWlengthT[1] = 5;
948 chctx->CWlengthT[2] = 5;
949 for (i = 1; i < 4; i++) {
950 if (stream_format_code & 0x1)
951 bits = 5;
952 else
953 bits = (chctx->levlCoeffBuf[i] == 16) ? 0 : 5;
954 chctx->bitsBandT[i] = bits;
955 for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
956 chctx->CWlengthT[j] = bits;
957 bitscount += bits;
958 }
959 }
960 }
961 if (avctx->codec_id == AV_CODEC_ID_IAC) {
962 bitscount += !!chctx->bandWidthT[BANDS - 1];
963 if (!(stream_format_code & 0x2))
964 bitscount += 16;
965 }
966
967 if ((ret = bit_allocation(q, chctx, stream_format_code,
968 512 - bitscount - get_bits_count(&q->gb),
969 flag)) < 0) {
970 av_log(avctx, AV_LOG_ERROR, "Bit allocations failed\n");
971 chctx->decoder_reset = 1;
972 return ret;
973 }
974
975 if (stream_format_code & 0x1) {
976 for (i = 0; i < BANDS; i++)
977 chctx->skipFlags[i] = 0;
978 } else {
979 imc_refine_bit_allocation(q, chctx);
980 }
981
982 for (i = 0; i < BANDS; i++) {
983 chctx->sumLenArr[i] = 0;
984
985 for (j = band_tab[i]; j < band_tab[i + 1]; j++)
986 if (!chctx->skipFlags[j])
987 chctx->sumLenArr[i] += chctx->CWlengthT[j];
988 }
989
990 memset(chctx->codewords, 0, sizeof(chctx->codewords));
991
992 if (imc_get_coeffs(q, chctx) < 0) {
993 av_log(avctx, AV_LOG_ERROR, "Read coefficients failed\n");
994 chctx->decoder_reset = 1;
995 return AVERROR_INVALIDDATA;
996 }
997
998 if (inverse_quant_coeff(q, chctx, stream_format_code) < 0) {
999 av_log(avctx, AV_LOG_ERROR, "Inverse quantization of coefficients failed\n");
1000 chctx->decoder_reset = 1;
1001 return AVERROR_INVALIDDATA;
1002 }
1003
1004 memset(chctx->skipFlags, 0, sizeof(chctx->skipFlags));
1005
1006 imc_imdct256(q, chctx, avctx->channels);
1007
1008 return 0;
1009}
1010
1011static int imc_decode_frame(AVCodecContext *avctx, void *data,
1012 int *got_frame_ptr, AVPacket *avpkt)
1013{
1014 AVFrame *frame = data;
1015 const uint8_t *buf = avpkt->data;
1016 int buf_size = avpkt->size;
1017 int ret, i;
1018
1019 IMCContext *q = avctx->priv_data;
1020
1021 LOCAL_ALIGNED_16(uint16_t, buf16, [IMC_BLOCK_SIZE / 2 + FF_INPUT_BUFFER_PADDING_SIZE/2]);
1022
1023 if (buf_size < IMC_BLOCK_SIZE * avctx->channels) {
1024 av_log(avctx, AV_LOG_ERROR, "frame too small!\n");
1025 return AVERROR_INVALIDDATA;
1026 }
1027
1028 /* get output buffer */
1029 frame->nb_samples = COEFFS;
1030 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1031 return ret;
1032
1033 for (i = 0; i < avctx->channels; i++) {
1034 q->out_samples = (float *)frame->extended_data[i];
1035
1036 q->bdsp.bswap16_buf(buf16, (const uint16_t *) buf, IMC_BLOCK_SIZE / 2);
1037
1038 init_get_bits(&q->gb, (const uint8_t*)buf16, IMC_BLOCK_SIZE * 8);
1039
1040 buf += IMC_BLOCK_SIZE;
1041
1042 if ((ret = imc_decode_block(avctx, q, i)) < 0)
1043 return ret;
1044 }
1045
1046 if (avctx->channels == 2) {
1047 q->fdsp.butterflies_float((float *)frame->extended_data[0],
1048 (float *)frame->extended_data[1], COEFFS);
1049 }
1050
1051 *got_frame_ptr = 1;
1052
1053 return IMC_BLOCK_SIZE * avctx->channels;
1054}
1055
1056
1057static av_cold int imc_decode_close(AVCodecContext * avctx)
1058{
1059 IMCContext *q = avctx->priv_data;
1060
1061 ff_fft_end(&q->fft);
1062
1063 return 0;
1064}
1065
1066static av_cold void flush(AVCodecContext *avctx)
1067{
1068 IMCContext *q = avctx->priv_data;
1069
1070 q->chctx[0].decoder_reset =
1071 q->chctx[1].decoder_reset = 1;
1072}
1073
1074#if CONFIG_IMC_DECODER
1075AVCodec ff_imc_decoder = {
1076 .name = "imc",
1077 .long_name = NULL_IF_CONFIG_SMALL("IMC (Intel Music Coder)"),
1078 .type = AVMEDIA_TYPE_AUDIO,
1079 .id = AV_CODEC_ID_IMC,
1080 .priv_data_size = sizeof(IMCContext),
1081 .init = imc_decode_init,
1082 .close = imc_decode_close,
1083 .decode = imc_decode_frame,
1084 .flush = flush,
1085 .capabilities = CODEC_CAP_DR1,
1086 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1087 AV_SAMPLE_FMT_NONE },
1088};
1089#endif
1090#if CONFIG_IAC_DECODER
1091AVCodec ff_iac_decoder = {
1092 .name = "iac",
1093 .long_name = NULL_IF_CONFIG_SMALL("IAC (Indeo Audio Coder)"),
1094 .type = AVMEDIA_TYPE_AUDIO,
1095 .id = AV_CODEC_ID_IAC,
1096 .priv_data_size = sizeof(IMCContext),
1097 .init = imc_decode_init,
1098 .close = imc_decode_close,
1099 .decode = imc_decode_frame,
1100 .flush = flush,
1101 .capabilities = CODEC_CAP_DR1,
1102 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1103 AV_SAMPLE_FMT_NONE },
1104};
1105#endif
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