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Replace LDLATEFLAGS hackery by proper LDFLAGS tests.
[FFMpeg-mirror/ffmpeg-vdpau.git] / libavcodec / imc.c
blobd316ba4cbb1d07cee15fe187646e8cfe013ed4d6
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 imc.c IMC - Intel Music Coder
26 * A mdct based codec using a 256 points large transform
27 * divied into 32 bands with some mix of scale factors.
28 * Only mono is supported.
29 *
30 */
31
32
33 #include <math.h>
34 #include <stddef.h>
35 #include <stdio.h>
36
37 #define ALT_BITSTREAM_READER
38 #include "avcodec.h"
39 #include "bitstream.h"
40 #include "dsputil.h"
41
42 #include "imcdata.h"
43
44 #define IMC_BLOCK_SIZE 64
45 #define IMC_FRAME_ID 0x21
46 #define BANDS 32
47 #define COEFFS 256
48
49 typedef struct {
50 float old_floor[BANDS];
51 float flcoeffs1[BANDS];
52 float flcoeffs2[BANDS];
53 float flcoeffs3[BANDS];
54 float flcoeffs4[BANDS];
55 float flcoeffs5[BANDS];
56 float flcoeffs6[BANDS];
57 float CWdecoded[COEFFS];
58
59 /** MDCT tables */
60 //@{
61 float mdct_sine_window[COEFFS];
62 float post_cos[COEFFS];
63 float post_sin[COEFFS];
64 float pre_coef1[COEFFS];
65 float pre_coef2[COEFFS];
66 float last_fft_im[COEFFS];
67 //@}
68
69 int bandWidthT[BANDS]; ///< codewords per band
70 int bitsBandT[BANDS]; ///< how many bits per codeword in band
71 int CWlengthT[COEFFS]; ///< how many bits in each codeword
72 int levlCoeffBuf[BANDS];
73 int bandFlagsBuf[BANDS]; ///< flags for each band
74 int sumLenArr[BANDS]; ///< bits for all coeffs in band
75 int skipFlagRaw[BANDS]; ///< skip flags are stored in raw form or not
76 int skipFlagBits[BANDS]; ///< bits used to code skip flags
77 int skipFlagCount[BANDS]; ///< skipped coeffients per band
78 int skipFlags[COEFFS]; ///< skip coefficient decoding or not
79 int codewords[COEFFS]; ///< raw codewords read from bitstream
80 float sqrt_tab[30];
81 GetBitContext gb;
82 int decoder_reset;
83 float one_div_log2;
84
85 DSPContext dsp;
86 FFTContext fft;
87 DECLARE_ALIGNED_16(FFTComplex, samples[COEFFS/2]);
88 DECLARE_ALIGNED_16(float, out_samples[COEFFS]);
89 } IMCContext;
90
91 static VLC huffman_vlc[4][4];
92
93 #define VLC_TABLES_SIZE 9512
94
95 static const int vlc_offsets[17] = {
96 0, 640, 1156, 1732, 2308, 2852, 3396, 3924,
97 4452, 5220, 5860, 6628, 7268, 7908, 8424, 8936, VLC_TABLES_SIZE};
98
99 static VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2];
100
101 static av_cold int imc_decode_init(AVCodecContext * avctx)
102 {
103 int i, j;
104 IMCContext *q = avctx->priv_data;
105 double r1, r2;
106
107 q->decoder_reset = 1;
108
109 for(i = 0; i < BANDS; i++)
110 q->old_floor[i] = 1.0;
111
112 /* Build mdct window, a simple sine window normalized with sqrt(2) */
113 ff_sine_window_init(q->mdct_sine_window, COEFFS);
114 for(i = 0; i < COEFFS; i++)
115 q->mdct_sine_window[i] *= sqrt(2.0);
116 for(i = 0; i < COEFFS/2; i++){
117 q->post_cos[i] = cos(i / 256.0 * M_PI);
118 q->post_sin[i] = sin(i / 256.0 * M_PI);
119
120 r1 = sin((i * 4.0 + 1.0) / 1024.0 * M_PI);
121 r2 = cos((i * 4.0 + 1.0) / 1024.0 * M_PI);
122
123 if (i & 0x1)
124 {
125 q->pre_coef1[i] = (r1 + r2) * sqrt(2.0);
126 q->pre_coef2[i] = -(r1 - r2) * sqrt(2.0);
127 }
128 else
129 {
130 q->pre_coef1[i] = -(r1 + r2) * sqrt(2.0);
131 q->pre_coef2[i] = (r1 - r2) * sqrt(2.0);
132 }
133
134 q->last_fft_im[i] = 0;
135 }
136
137 /* Generate a square root table */
138
139 for(i = 0; i < 30; i++) {
140 q->sqrt_tab[i] = sqrt(i);
141 }
142
143 /* initialize the VLC tables */
144 for(i = 0; i < 4 ; i++) {
145 for(j = 0; j < 4; j++) {
146 huffman_vlc[i][j].table = vlc_tables[vlc_offsets[i * 4 + j]];
147 huffman_vlc[i][j].table_allocated = vlc_offsets[i * 4 + j + 1] - vlc_offsets[i * 4 + j];
148 init_vlc(&huffman_vlc[i][j], 9, imc_huffman_sizes[i],
149 imc_huffman_lens[i][j], 1, 1,
150 imc_huffman_bits[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC);
151 }
152 }
153 q->one_div_log2 = 1/log(2);
154
155 ff_fft_init(&q->fft, 7, 1);
156 dsputil_init(&q->dsp, avctx);
157 return 0;
158 }
159
160 static void imc_calculate_coeffs(IMCContext* q, float* flcoeffs1, float* flcoeffs2, int* bandWidthT,
161 float* flcoeffs3, float* flcoeffs5)
162 {
163 float workT1[BANDS];
164 float workT2[BANDS];
165 float workT3[BANDS];
166 float snr_limit = 1.e-30;
167 float accum = 0.0;
168 int i, cnt2;
169
170 for(i = 0; i < BANDS; i++) {
171 flcoeffs5[i] = workT2[i] = 0.0;
172 if (bandWidthT[i]){
173 workT1[i] = flcoeffs1[i] * flcoeffs1[i];
174 flcoeffs3[i] = 2.0 * flcoeffs2[i];
175 } else {
176 workT1[i] = 0.0;
177 flcoeffs3[i] = -30000.0;
178 }
179 workT3[i] = bandWidthT[i] * workT1[i] * 0.01;
180 if (workT3[i] <= snr_limit)
181 workT3[i] = 0.0;
182 }
183
184 for(i = 0; i < BANDS; i++) {
185 for(cnt2 = i; cnt2 < cyclTab[i]; cnt2++)
186 flcoeffs5[cnt2] = flcoeffs5[cnt2] + workT3[i];
187 workT2[cnt2-1] = workT2[cnt2-1] + workT3[i];
188 }
189
190 for(i = 1; i < BANDS; i++) {
191 accum = (workT2[i-1] + accum) * imc_weights1[i-1];
192 flcoeffs5[i] += accum;
193 }
194
195 for(i = 0; i < BANDS; i++)
196 workT2[i] = 0.0;
197
198 for(i = 0; i < BANDS; i++) {
199 for(cnt2 = i-1; cnt2 > cyclTab2[i]; cnt2--)
200 flcoeffs5[cnt2] += workT3[i];
201 workT2[cnt2+1] += workT3[i];
202 }
203
204 accum = 0.0;
205
206 for(i = BANDS-2; i >= 0; i--) {
207 accum = (workT2[i+1] + accum) * imc_weights2[i];
208 flcoeffs5[i] += accum;
209 //there is missing code here, but it seems to never be triggered
210 }
211 }
212
213
214 static void imc_read_level_coeffs(IMCContext* q, int stream_format_code, int* levlCoeffs)
215 {
216 int i;
217 VLC *hufftab[4];
218 int start = 0;
219 const uint8_t *cb_sel;
220 int s;
221
222 s = stream_format_code >> 1;
223 hufftab[0] = &huffman_vlc[s][0];
224 hufftab[1] = &huffman_vlc[s][1];
225 hufftab[2] = &huffman_vlc[s][2];
226 hufftab[3] = &huffman_vlc[s][3];
227 cb_sel = imc_cb_select[s];
228
229 if(stream_format_code & 4)
230 start = 1;
231 if(start)
232 levlCoeffs[0] = get_bits(&q->gb, 7);
233 for(i = start; i < BANDS; i++){
234 levlCoeffs[i] = get_vlc2(&q->gb, hufftab[cb_sel[i]]->table, hufftab[cb_sel[i]]->bits, 2);
235 if(levlCoeffs[i] == 17)
236 levlCoeffs[i] += get_bits(&q->gb, 4);
237 }
238 }
239
240 static void imc_decode_level_coefficients(IMCContext* q, int* levlCoeffBuf, float* flcoeffs1,
241 float* flcoeffs2)
242 {
243 int i, level;
244 float tmp, tmp2;
245 //maybe some frequency division thingy
246
247 flcoeffs1[0] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
248 flcoeffs2[0] = log(flcoeffs1[0])/log(2);
249 tmp = flcoeffs1[0];
250 tmp2 = flcoeffs2[0];
251
252 for(i = 1; i < BANDS; i++) {
253 level = levlCoeffBuf[i];
254 if (level == 16) {
255 flcoeffs1[i] = 1.0;
256 flcoeffs2[i] = 0.0;
257 } else {
258 if (level < 17)
259 level -=7;
260 else if (level <= 24)
261 level -=32;
262 else
263 level -=16;
264
265 tmp *= imc_exp_tab[15 + level];
266 tmp2 += 0.83048 * level; // 0.83048 = log2(10) * 0.25
267 flcoeffs1[i] = tmp;
268 flcoeffs2[i] = tmp2;
269 }
270 }
271 }
272
273
274 static void imc_decode_level_coefficients2(IMCContext* q, int* levlCoeffBuf, float* old_floor, float* flcoeffs1,
275 float* flcoeffs2) {
276 int i;
277 //FIXME maybe flag_buf = noise coding and flcoeffs1 = new scale factors
278 // and flcoeffs2 old scale factors
279 // might be incomplete due to a missing table that is in the binary code
280 for(i = 0; i < BANDS; i++) {
281 flcoeffs1[i] = 0;
282 if(levlCoeffBuf[i] < 16) {
283 flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i];
284 flcoeffs2[i] = (levlCoeffBuf[i]-7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25
285 } else {
286 flcoeffs1[i] = old_floor[i];
287 }
288 }
289 }
290
291 /**
292 * Perform bit allocation depending on bits available
293 */
294 static int bit_allocation (IMCContext* q, int stream_format_code, int freebits, int flag) {
295 int i, j;
296 const float limit = -1.e20;
297 float highest = 0.0;
298 int indx;
299 int t1 = 0;
300 int t2 = 1;
301 float summa = 0.0;
302 int iacc = 0;
303 int summer = 0;
304 int rres, cwlen;
305 float lowest = 1.e10;
306 int low_indx = 0;
307 float workT[32];
308 int flg;
309 int found_indx = 0;
310
311 for(i = 0; i < BANDS; i++)
312 highest = FFMAX(highest, q->flcoeffs1[i]);
313
314 for(i = 0; i < BANDS-1; i++) {
315 q->flcoeffs4[i] = q->flcoeffs3[i] - log(q->flcoeffs5[i])/log(2);
316 }
317 q->flcoeffs4[BANDS - 1] = limit;
318
319 highest = highest * 0.25;
320
321 for(i = 0; i < BANDS; i++) {
322 indx = -1;
323 if ((band_tab[i+1] - band_tab[i]) == q->bandWidthT[i])
324 indx = 0;
325
326 if ((band_tab[i+1] - band_tab[i]) > q->bandWidthT[i])
327 indx = 1;
328
329 if (((band_tab[i+1] - band_tab[i])/2) >= q->bandWidthT[i])
330 indx = 2;
331
332 if (indx == -1)
333 return -1;
334
335 q->flcoeffs4[i] = q->flcoeffs4[i] + xTab[(indx*2 + (q->flcoeffs1[i] < highest)) * 2 + flag];
336 }
337
338 if (stream_format_code & 0x2) {
339 q->flcoeffs4[0] = limit;
340 q->flcoeffs4[1] = limit;
341 q->flcoeffs4[2] = limit;
342 q->flcoeffs4[3] = limit;
343 }
344
345 for(i = (stream_format_code & 0x2)?4:0; i < BANDS-1; i++) {
346 iacc += q->bandWidthT[i];
347 summa += q->bandWidthT[i] * q->flcoeffs4[i];
348 }
349 q->bandWidthT[BANDS-1] = 0;
350 summa = (summa * 0.5 - freebits) / iacc;
351
352
353 for(i = 0; i < BANDS/2; i++) {
354 rres = summer - freebits;
355 if((rres >= -8) && (rres <= 8)) break;
356
357 summer = 0;
358 iacc = 0;
359
360 for(j = (stream_format_code & 0x2)?4:0; j < BANDS; j++) {
361 cwlen = av_clip((int)((q->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6);
362
363 q->bitsBandT[j] = cwlen;
364 summer += q->bandWidthT[j] * cwlen;
365
366 if (cwlen > 0)
367 iacc += q->bandWidthT[j];
368 }
369
370 flg = t2;
371 t2 = 1;
372 if (freebits < summer)
373 t2 = -1;
374 if (i == 0)
375 flg = t2;
376 if(flg != t2)
377 t1++;
378
379 summa = (float)(summer - freebits) / ((t1 + 1) * iacc) + summa;
380 }
381
382 for(i = (stream_format_code & 0x2)?4:0; i < BANDS; i++) {
383 for(j = band_tab[i]; j < band_tab[i+1]; j++)
384 q->CWlengthT[j] = q->bitsBandT[i];
385 }
386
387 if (freebits > summer) {
388 for(i = 0; i < BANDS; i++) {
389 workT[i] = (q->bitsBandT[i] == 6) ? -1.e20 : (q->bitsBandT[i] * -2 + q->flcoeffs4[i] - 0.415);
390 }
391
392 highest = 0.0;
393
394 do{
395 if (highest <= -1.e20)
396 break;
397
398 found_indx = 0;
399 highest = -1.e20;
400
401 for(i = 0; i < BANDS; i++) {
402 if (workT[i] > highest) {
403 highest = workT[i];
404 found_indx = i;
405 }
406 }
407
408 if (highest > -1.e20) {
409 workT[found_indx] -= 2.0;
410 if (++(q->bitsBandT[found_indx]) == 6)
411 workT[found_indx] = -1.e20;
412
413 for(j = band_tab[found_indx]; j < band_tab[found_indx+1] && (freebits > summer); j++){
414 q->CWlengthT[j]++;
415 summer++;
416 }
417 }
418 }while (freebits > summer);
419 }
420 if (freebits < summer) {
421 for(i = 0; i < BANDS; i++) {
422 workT[i] = q->bitsBandT[i] ? (q->bitsBandT[i] * -2 + q->flcoeffs4[i] + 1.585) : 1.e20;
423 }
424 if (stream_format_code & 0x2) {
425 workT[0] = 1.e20;
426 workT[1] = 1.e20;
427 workT[2] = 1.e20;
428 workT[3] = 1.e20;
429 }
430 while (freebits < summer){
431 lowest = 1.e10;
432 low_indx = 0;
433 for(i = 0; i < BANDS; i++) {
434 if (workT[i] < lowest) {
435 lowest = workT[i];
436 low_indx = i;
437 }
438 }
439 //if(lowest >= 1.e10) break;
440 workT[low_indx] = lowest + 2.0;
441
442 if (!(--q->bitsBandT[low_indx]))
443 workT[low_indx] = 1.e20;
444
445 for(j = band_tab[low_indx]; j < band_tab[low_indx+1] && (freebits < summer); j++){
446 if(q->CWlengthT[j] > 0){
447 q->CWlengthT[j]--;
448 summer--;
449 }
450 }
451 }
452 }
453 return 0;
454 }
455
456 static void imc_get_skip_coeff(IMCContext* q) {
457 int i, j;
458
459 memset(q->skipFlagBits, 0, sizeof(q->skipFlagBits));
460 memset(q->skipFlagCount, 0, sizeof(q->skipFlagCount));
461 for(i = 0; i < BANDS; i++) {
462 if (!q->bandFlagsBuf[i] || !q->bandWidthT[i])
463 continue;
464
465 if (!q->skipFlagRaw[i]) {
466 q->skipFlagBits[i] = band_tab[i+1] - band_tab[i];
467
468 for(j = band_tab[i]; j < band_tab[i+1]; j++) {
469 if ((q->skipFlags[j] = get_bits1(&q->gb)))
470 q->skipFlagCount[i]++;
471 }
472 } else {
473 for(j = band_tab[i]; j < (band_tab[i+1]-1); j += 2) {
474 if(!get_bits1(&q->gb)){//0
475 q->skipFlagBits[i]++;
476 q->skipFlags[j]=1;
477 q->skipFlags[j+1]=1;
478 q->skipFlagCount[i] += 2;
479 }else{
480 if(get_bits1(&q->gb)){//11
481 q->skipFlagBits[i] +=2;
482 q->skipFlags[j]=0;
483 q->skipFlags[j+1]=1;
484 q->skipFlagCount[i]++;
485 }else{
486 q->skipFlagBits[i] +=3;
487 q->skipFlags[j+1]=0;
488 if(!get_bits1(&q->gb)){//100
489 q->skipFlags[j]=1;
490 q->skipFlagCount[i]++;
491 }else{//101
492 q->skipFlags[j]=0;
493 }
494 }
495 }
496 }
497
498 if (j < band_tab[i+1]) {
499 q->skipFlagBits[i]++;
500 if ((q->skipFlags[j] = get_bits1(&q->gb)))
501 q->skipFlagCount[i]++;
502 }
503 }
504 }
505 }
506
507 /**
508 * Increase highest' band coefficient sizes as some bits won't be used
509 */
510 static void imc_adjust_bit_allocation (IMCContext* q, int summer) {
511 float workT[32];
512 int corrected = 0;
513 int i, j;
514 float highest = 0;
515 int found_indx=0;
516
517 for(i = 0; i < BANDS; i++) {
518 workT[i] = (q->bitsBandT[i] == 6) ? -1.e20 : (q->bitsBandT[i] * -2 + q->flcoeffs4[i] - 0.415);
519 }
520
521 while (corrected < summer) {
522 if(highest <= -1.e20)
523 break;
524
525 highest = -1.e20;
526
527 for(i = 0; i < BANDS; i++) {
528 if (workT[i] > highest) {
529 highest = workT[i];
530 found_indx = i;
531 }
532 }
533
534 if (highest > -1.e20) {
535 workT[found_indx] -= 2.0;
536 if (++(q->bitsBandT[found_indx]) == 6)
537 workT[found_indx] = -1.e20;
538
539 for(j = band_tab[found_indx]; j < band_tab[found_indx+1] && (corrected < summer); j++) {
540 if (!q->skipFlags[j] && (q->CWlengthT[j] < 6)) {
541 q->CWlengthT[j]++;
542 corrected++;
543 }
544 }
545 }
546 }
547 }
548
549 static void imc_imdct256(IMCContext *q) {
550 int i;
551 float re, im;
552
553 /* prerotation */
554 for(i=0; i < COEFFS/2; i++){
555 q->samples[i].re = -(q->pre_coef1[i] * q->CWdecoded[COEFFS-1-i*2]) -
556 (q->pre_coef2[i] * q->CWdecoded[i*2]);
557 q->samples[i].im = (q->pre_coef2[i] * q->CWdecoded[COEFFS-1-i*2]) -
558 (q->pre_coef1[i] * q->CWdecoded[i*2]);
559 }
560
561 /* FFT */
562 ff_fft_permute(&q->fft, q->samples);
563 ff_fft_calc (&q->fft, q->samples);
564
565 /* postrotation, window and reorder */
566 for(i = 0; i < COEFFS/2; i++){
567 re = (q->samples[i].re * q->post_cos[i]) + (-q->samples[i].im * q->post_sin[i]);
568 im = (-q->samples[i].im * q->post_cos[i]) - (q->samples[i].re * q->post_sin[i]);
569 q->out_samples[i*2] = (q->mdct_sine_window[COEFFS-1-i*2] * q->last_fft_im[i]) + (q->mdct_sine_window[i*2] * re);
570 q->out_samples[COEFFS-1-i*2] = (q->mdct_sine_window[i*2] * q->last_fft_im[i]) - (q->mdct_sine_window[COEFFS-1-i*2] * re);
571 q->last_fft_im[i] = im;
572 }
573 }
574
575 static int inverse_quant_coeff (IMCContext* q, int stream_format_code) {
576 int i, j;
577 int middle_value, cw_len, max_size;
578 const float* quantizer;
579
580 for(i = 0; i < BANDS; i++) {
581 for(j = band_tab[i]; j < band_tab[i+1]; j++) {
582 q->CWdecoded[j] = 0;
583 cw_len = q->CWlengthT[j];
584
585 if (cw_len <= 0 || q->skipFlags[j])
586 continue;
587
588 max_size = 1 << cw_len;
589 middle_value = max_size >> 1;
590
591 if (q->codewords[j] >= max_size || q->codewords[j] < 0)
592 return -1;
593
594 if (cw_len >= 4){
595 quantizer = imc_quantizer2[(stream_format_code & 2) >> 1];
596 if (q->codewords[j] >= middle_value)
597 q->CWdecoded[j] = quantizer[q->codewords[j] - 8] * q->flcoeffs6[i];
598 else
599 q->CWdecoded[j] = -quantizer[max_size - q->codewords[j] - 8 - 1] * q->flcoeffs6[i];
600 }else{
601 quantizer = imc_quantizer1[((stream_format_code & 2) >> 1) | (q->bandFlagsBuf[i] << 1)];
602 if (q->codewords[j] >= middle_value)
603 q->CWdecoded[j] = quantizer[q->codewords[j] - 1] * q->flcoeffs6[i];
604 else
605 q->CWdecoded[j] = -quantizer[max_size - 2 - q->codewords[j]] * q->flcoeffs6[i];
606 }
607 }
608 }
609 return 0;
610 }
611
612
613 static int imc_get_coeffs (IMCContext* q) {
614 int i, j, cw_len, cw;
615
616 for(i = 0; i < BANDS; i++) {
617 if(!q->sumLenArr[i]) continue;
618 if (q->bandFlagsBuf[i] || q->bandWidthT[i]) {
619 for(j = band_tab[i]; j < band_tab[i+1]; j++) {
620 cw_len = q->CWlengthT[j];
621 cw = 0;
622
623 if (get_bits_count(&q->gb) + cw_len > 512){
624 //av_log(NULL,0,"Band %i coeff %i cw_len %i\n",i,j,cw_len);
625 return -1;
626 }
627
628 if(cw_len && (!q->bandFlagsBuf[i] || !q->skipFlags[j]))
629 cw = get_bits(&q->gb, cw_len);
630
631 q->codewords[j] = cw;
632 }
633 }
634 }
635 return 0;
636 }
637
638 static int imc_decode_frame(AVCodecContext * avctx,
639 void *data, int *data_size,
640 const uint8_t * buf, int buf_size)
641 {
642
643 IMCContext *q = avctx->priv_data;
644
645 int stream_format_code;
646 int imc_hdr, i, j;
647 int flag;
648 int bits, summer;
649 int counter, bitscount;
650 uint16_t buf16[IMC_BLOCK_SIZE / 2];
651
652 if (buf_size < IMC_BLOCK_SIZE) {
653 av_log(avctx, AV_LOG_ERROR, "imc frame too small!\n");
654 return -1;
655 }
656 for(i = 0; i < IMC_BLOCK_SIZE / 2; i++)
657 buf16[i] = bswap_16(((const uint16_t*)buf)[i]);
658
659 init_get_bits(&q->gb, (const uint8_t*)buf16, IMC_BLOCK_SIZE * 8);
660
661 /* Check the frame header */
662 imc_hdr = get_bits(&q->gb, 9);
663 if (imc_hdr != IMC_FRAME_ID) {
664 av_log(avctx, AV_LOG_ERROR, "imc frame header check failed!\n");
665 av_log(avctx, AV_LOG_ERROR, "got %x instead of 0x21.\n", imc_hdr);
666 return -1;
667 }
668 stream_format_code = get_bits(&q->gb, 3);
669
670 if(stream_format_code & 1){
671 av_log(avctx, AV_LOG_ERROR, "Stream code format %X is not supported\n", stream_format_code);
672 return -1;
673 }
674
675 // av_log(avctx, AV_LOG_DEBUG, "stream_format_code = %d\n", stream_format_code);
676
677 if (stream_format_code & 0x04)
678 q->decoder_reset = 1;
679
680 if(q->decoder_reset) {
681 memset(q->out_samples, 0, sizeof(q->out_samples));
682 for(i = 0; i < BANDS; i++)q->old_floor[i] = 1.0;
683 for(i = 0; i < COEFFS; i++)q->CWdecoded[i] = 0;
684 q->decoder_reset = 0;
685 }
686
687 flag = get_bits1(&q->gb);
688 imc_read_level_coeffs(q, stream_format_code, q->levlCoeffBuf);
689
690 if (stream_format_code & 0x4)
691 imc_decode_level_coefficients(q, q->levlCoeffBuf, q->flcoeffs1, q->flcoeffs2);
692 else
693 imc_decode_level_coefficients2(q, q->levlCoeffBuf, q->old_floor, q->flcoeffs1, q->flcoeffs2);
694
695 memcpy(q->old_floor, q->flcoeffs1, 32 * sizeof(float));
696
697 counter = 0;
698 for (i=0 ; i<BANDS ; i++) {
699 if (q->levlCoeffBuf[i] == 16) {
700 q->bandWidthT[i] = 0;
701 counter++;
702 } else
703 q->bandWidthT[i] = band_tab[i+1] - band_tab[i];
704 }
705 memset(q->bandFlagsBuf, 0, BANDS * sizeof(int));
706 for(i = 0; i < BANDS-1; i++) {
707 if (q->bandWidthT[i])
708 q->bandFlagsBuf[i] = get_bits1(&q->gb);
709 }
710
711 imc_calculate_coeffs(q, q->flcoeffs1, q->flcoeffs2, q->bandWidthT, q->flcoeffs3, q->flcoeffs5);
712
713 bitscount = 0;
714 /* first 4 bands will be assigned 5 bits per coefficient */
715 if (stream_format_code & 0x2) {
716 bitscount += 15;
717
718 q->bitsBandT[0] = 5;
719 q->CWlengthT[0] = 5;
720 q->CWlengthT[1] = 5;
721 q->CWlengthT[2] = 5;
722 for(i = 1; i < 4; i++){
723 bits = (q->levlCoeffBuf[i] == 16) ? 0 : 5;
724 q->bitsBandT[i] = bits;
725 for(j = band_tab[i]; j < band_tab[i+1]; j++) {
726 q->CWlengthT[j] = bits;
727 bitscount += bits;
728 }
729 }
730 }
731
732 if(bit_allocation (q, stream_format_code, 512 - bitscount - get_bits_count(&q->gb), flag) < 0) {
733 av_log(avctx, AV_LOG_ERROR, "Bit allocations failed\n");
734 q->decoder_reset = 1;
735 return -1;
736 }
737
738 for(i = 0; i < BANDS; i++) {
739 q->sumLenArr[i] = 0;
740 q->skipFlagRaw[i] = 0;
741 for(j = band_tab[i]; j < band_tab[i+1]; j++)
742 q->sumLenArr[i] += q->CWlengthT[j];
743 if (q->bandFlagsBuf[i])
744 if( (((band_tab[i+1] - band_tab[i]) * 1.5) > q->sumLenArr[i]) && (q->sumLenArr[i] > 0))
745 q->skipFlagRaw[i] = 1;
746 }
747
748 imc_get_skip_coeff(q);
749
750 for(i = 0; i < BANDS; i++) {
751 q->flcoeffs6[i] = q->flcoeffs1[i];
752 /* band has flag set and at least one coded coefficient */
753 if (q->bandFlagsBuf[i] && (band_tab[i+1] - band_tab[i]) != q->skipFlagCount[i]){
754 q->flcoeffs6[i] *= q->sqrt_tab[band_tab[i+1] - band_tab[i]] /
755 q->sqrt_tab[(band_tab[i+1] - band_tab[i] - q->skipFlagCount[i])];
756 }
757 }
758
759 /* calculate bits left, bits needed and adjust bit allocation */
760 bits = summer = 0;
761
762 for(i = 0; i < BANDS; i++) {
763 if (q->bandFlagsBuf[i]) {
764 for(j = band_tab[i]; j < band_tab[i+1]; j++) {
765 if(q->skipFlags[j]) {
766 summer += q->CWlengthT[j];
767 q->CWlengthT[j] = 0;
768 }
769 }
770 bits += q->skipFlagBits[i];
771 summer -= q->skipFlagBits[i];
772 }
773 }
774 imc_adjust_bit_allocation(q, summer);
775
776 for(i = 0; i < BANDS; i++) {
777 q->sumLenArr[i] = 0;
778
779 for(j = band_tab[i]; j < band_tab[i+1]; j++)
780 if (!q->skipFlags[j])
781 q->sumLenArr[i] += q->CWlengthT[j];
782 }
783
784 memset(q->codewords, 0, sizeof(q->codewords));
785
786 if(imc_get_coeffs(q) < 0) {
787 av_log(avctx, AV_LOG_ERROR, "Read coefficients failed\n");
788 q->decoder_reset = 1;
789 return 0;
790 }
791
792 if(inverse_quant_coeff(q, stream_format_code) < 0) {
793 av_log(avctx, AV_LOG_ERROR, "Inverse quantization of coefficients failed\n");
794 q->decoder_reset = 1;
795 return 0;
796 }
797
798 memset(q->skipFlags, 0, sizeof(q->skipFlags));
799
800 imc_imdct256(q);
801
802 q->dsp.float_to_int16(data, q->out_samples, COEFFS);
803
804 *data_size = COEFFS * sizeof(int16_t);
805
806 return IMC_BLOCK_SIZE;
807 }
808
809
810 static av_cold int imc_decode_close(AVCodecContext * avctx)
811 {
812 IMCContext *q = avctx->priv_data;
813
814 ff_fft_end(&q->fft);
815 return 0;
816 }
817
818
819 AVCodec imc_decoder = {
820 .name = "imc",
821 .type = CODEC_TYPE_AUDIO,
822 .id = CODEC_ID_IMC,
823 .priv_data_size = sizeof(IMCContext),
824 .init = imc_decode_init,
825 .close = imc_decode_close,
826 .decode = imc_decode_frame,
827 .long_name = NULL_IF_CONFIG_SMALL("IMC (Intel Music Coder)"),
828 };
VDPAU for FFmpeg