Add docu of struct asf_header_info.
[paraslash.git] / wmadec_filter.c
1 /*
2 * WMA compatible decoder
3 *
4 * Extracted 2009 from the mplayer source code 2009-02-10.
5 *
6 * Copyright (c) 2002 The FFmpeg Project
7 *
8 * Licensed under the GNU Lesser General Public License.
9 * For licencing details see COPYING.LIB.
10 */
11
12 /** * \file wmadec_filter.c paraslash's WMA decoder. */
13
14 /*
15 * This decoder handles Microsoft Windows Media Audio data version 2.
16 */
17
18 #define _XOPEN_SOURCE 600
19
20 #include <sys/time.h>
21 #include <inttypes.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <math.h>
25 #include <string.h>
26 #include <regex.h>
27
28 #include "para.h"
29 #include "error.h"
30 #include "list.h"
31 #include "ggo.h"
32 #include "string.h"
33 #include "sched.h"
34 #include "filter.h"
35 #include "bitstream.h"
36 #include "imdct.h"
37 #include "wma.h"
38 #include "wmadata.h"
39
40
41 /* size of blocks */
42 #define BLOCK_MIN_BITS 7
43 #define BLOCK_MAX_BITS 11
44 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
45
46 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
47
48 /* XXX: find exact max size */
49 #define HIGH_BAND_MAX_SIZE 16
50
51 /* XXX: is it a suitable value ? */
52 #define MAX_CODED_SUPERFRAME_SIZE 16384
53
54 #define MAX_CHANNELS 2
55
56 #define NOISE_TAB_SIZE 8192
57
58 #define LSP_POW_BITS 7
59
60 struct private_wmadec_data {
61 struct asf_header_info ahi;
62 struct getbit_context gb;
63 int use_bit_reservoir;
64 int use_variable_block_len;
65 int use_exp_vlc; ///< exponent coding: 0 = lsp, 1 = vlc + delta
66 int use_noise_coding; ///< true if perceptual noise is added
67 int byte_offset_bits;
68 struct vlc exp_vlc;
69 int exponent_sizes[BLOCK_NB_SIZES];
70 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
71 int high_band_start[BLOCK_NB_SIZES]; ///< index of first coef in high band
72 int coefs_start; ///< first coded coef
73 int coefs_end[BLOCK_NB_SIZES]; ///< max number of coded coefficients
74 int exponent_high_sizes[BLOCK_NB_SIZES];
75 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
76 struct vlc hgain_vlc;
77
78 /* coded values in high bands */
79 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
80 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
81
82 /* there are two possible tables for spectral coefficients */
83 struct vlc coef_vlc[2];
84 uint16_t *run_table[2];
85 uint16_t *level_table[2];
86 uint16_t *int_table[2];
87 const struct coef_vlc_table *coef_vlcs[2];
88 /* frame info */
89 int frame_len; ///< frame length in samples
90 int frame_len_bits; ///< frame_len = 1 << frame_len_bits
91 int nb_block_sizes; ///< number of block sizes
92 /* block info */
93 int reset_block_lengths;
94 int block_len_bits; ///< log2 of current block length
95 int next_block_len_bits; ///< log2 of next block length
96 int prev_block_len_bits; ///< log2 of prev block length
97 int block_len; ///< block length in samples
98 int block_pos; ///< current position in frame
99 uint8_t ms_stereo; ///< true if mid/side stereo mode
100 uint8_t channel_coded[MAX_CHANNELS]; ///< true if channel is coded
101 int exponents_bsize[MAX_CHANNELS]; ///< log2 ratio frame/exp. length
102 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
103 float max_exponent[MAX_CHANNELS];
104 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
105 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
106 float output[BLOCK_MAX_SIZE * 2];
107 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
108 float *windows[BLOCK_NB_SIZES];
109 /* output buffer for one frame and the last for IMDCT windowing */
110 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
111 /* last frame info */
112 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
113 int last_bitoffset;
114 int last_superframe_len;
115 float noise_table[NOISE_TAB_SIZE];
116 int noise_index;
117 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
118 /* lsp_to_curve tables */
119 float lsp_cos_table[BLOCK_MAX_SIZE];
120 float lsp_pow_e_table[256];
121 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
122 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
123 };
124
125 #define EXPVLCBITS 8
126 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)
127
128 #define HGAINVLCBITS 9
129 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
130
131 #define VLCBITS 9
132 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
133
134 DECLARE_ALIGNED(16, float, ff_sine_128[128]);
135 DECLARE_ALIGNED(16, float, ff_sine_256[256]);
136 DECLARE_ALIGNED(16, float, ff_sine_512[512]);
137 DECLARE_ALIGNED(16, float, ff_sine_1024[1024]);
138 DECLARE_ALIGNED(16, float, ff_sine_2048[2048]);
139 DECLARE_ALIGNED(16, float, ff_sine_4096[4096]);
140
141 static float *ff_sine_windows[6] = {
142 ff_sine_128, ff_sine_256, ff_sine_512, ff_sine_1024,
143 ff_sine_2048, ff_sine_4096
144 };
145
146 /* Generate a sine window. */
147 static void sine_window_init(float *window, int n)
148 {
149 int i;
150
151 for (i = 0; i < n; i++)
152 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
153 }
154
155 static int wmadec_cleanup(struct private_wmadec_data *s)
156 {
157 int i;
158
159 for (i = 0; i < s->nb_block_sizes; i++)
160 imdct_end(s->mdct_ctx[i]);
161
162 if (s->use_exp_vlc)
163 free_vlc(&s->exp_vlc);
164 if (s->use_noise_coding)
165 free_vlc(&s->hgain_vlc);
166 for (i = 0; i < 2; i++) {
167 free_vlc(&s->coef_vlc[i]);
168 free(s->run_table[i]);
169 free(s->level_table[i]);
170 free(s->int_table[i]);
171 }
172 return 0;
173 }
174
175 /* XXX: use same run/length optimization as mpeg decoders */
176 //FIXME maybe split decode / encode or pass flag
177 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
178 uint16_t **plevel_table, uint16_t **pint_table,
179 const struct coef_vlc_table *vlc_table)
180 {
181 int n = vlc_table->n;
182 const uint8_t *table_bits = vlc_table->huffbits;
183 const uint32_t *table_codes = vlc_table->huffcodes;
184 const uint16_t *levels_table = vlc_table->levels;
185 uint16_t *run_table, *level_table, *int_table;
186 int i, l, j, k, level;
187
188 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4);
189
190 run_table = para_malloc(n * sizeof(uint16_t));
191 level_table = para_malloc(n * sizeof(uint16_t));
192 int_table = para_malloc(n * sizeof(uint16_t));
193 i = 2;
194 level = 1;
195 k = 0;
196 while (i < n) {
197 int_table[k] = i;
198 l = levels_table[k++];
199 for (j = 0; j < l; j++) {
200 run_table[i] = j;
201 level_table[i] = level;
202 i++;
203 }
204 level++;
205 }
206 *prun_table = run_table;
207 *plevel_table = level_table;
208 *pint_table = int_table;
209 }
210
211 /* compute the scale factor band sizes for each MDCT block size */
212 static void compute_scale_factor_band_sizes(struct private_wmadec_data *s,
213 float high_freq)
214 {
215 struct asf_header_info *ahi = &s->ahi;
216 int a, b, pos, lpos, k, block_len, i, j, n;
217 const uint8_t *table;
218
219 s->coefs_start = 0;
220 for (k = 0; k < s->nb_block_sizes; k++) {
221 block_len = s->frame_len >> k;
222
223 table = NULL;
224 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
225 if (a < 3) {
226 if (ahi->sample_rate >= 44100)
227 table = exponent_band_44100[a];
228 else if (ahi->sample_rate >= 32000)
229 table = exponent_band_32000[a];
230 else if (ahi->sample_rate >= 22050)
231 table = exponent_band_22050[a];
232 }
233 if (table) {
234 n = *table++;
235 for (i = 0; i < n; i++)
236 s->exponent_bands[k][i] = table[i];
237 s->exponent_sizes[k] = n;
238 } else {
239 j = 0;
240 lpos = 0;
241 for (i = 0; i < 25; i++) {
242 a = wma_critical_freqs[i];
243 b = ahi->sample_rate;
244 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
245 pos <<= 2;
246 if (pos > block_len)
247 pos = block_len;
248 if (pos > lpos)
249 s->exponent_bands[k][j++] = pos - lpos;
250 if (pos >= block_len)
251 break;
252 lpos = pos;
253 }
254 s->exponent_sizes[k] = j;
255 }
256
257 /* max number of coefs */
258 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
259 /* high freq computation */
260 s->high_band_start[k] = (int) ((block_len * 2 * high_freq)
261 / ahi->sample_rate + 0.5);
262 n = s->exponent_sizes[k];
263 j = 0;
264 pos = 0;
265 for (i = 0; i < n; i++) {
266 int start, end;
267 start = pos;
268 pos += s->exponent_bands[k][i];
269 end = pos;
270 if (start < s->high_band_start[k])
271 start = s->high_band_start[k];
272 if (end > s->coefs_end[k])
273 end = s->coefs_end[k];
274 if (end > start)
275 s->exponent_high_bands[k][j++] = end - start;
276 }
277 s->exponent_high_sizes[k] = j;
278 }
279 }
280
281 static int wma_init(struct private_wmadec_data *s, int flags2, struct asf_header_info *ahi)
282 {
283 int i;
284 float bps1, high_freq;
285 volatile float bps;
286 int sample_rate1;
287 int coef_vlc_table;
288
289 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
290 || ahi->channels <= 0 || ahi->channels > 8
291 || ahi->bit_rate <= 0)
292 return -E_WMA_BAD_PARAMS;
293
294 /* compute MDCT block size */
295 if (ahi->sample_rate <= 16000) {
296 s->frame_len_bits = 9;
297 } else if (ahi->sample_rate <= 22050) {
298 s->frame_len_bits = 10;
299 } else {
300 s->frame_len_bits = 11;
301 }
302 s->frame_len = 1 << s->frame_len_bits;
303 if (s->use_variable_block_len) {
304 int nb_max, nb;
305 nb = ((flags2 >> 3) & 3) + 1;
306 if ((ahi->bit_rate / ahi->channels) >= 32000)
307 nb += 2;
308 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
309 if (nb > nb_max)
310 nb = nb_max;
311 s->nb_block_sizes = nb + 1;
312 } else {
313 s->nb_block_sizes = 1;
314 }
315
316 /* init rate dependent parameters */
317 s->use_noise_coding = 1;
318 high_freq = ahi->sample_rate * 0.5;
319
320 /* wma2 rates are normalized */
321 sample_rate1 = ahi->sample_rate;
322 if (sample_rate1 >= 44100)
323 sample_rate1 = 44100;
324 else if (sample_rate1 >= 22050)
325 sample_rate1 = 22050;
326 else if (sample_rate1 >= 16000)
327 sample_rate1 = 16000;
328 else if (sample_rate1 >= 11025)
329 sample_rate1 = 11025;
330 else if (sample_rate1 >= 8000)
331 sample_rate1 = 8000;
332
333 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
334 s->byte_offset_bits = wma_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
335 /*
336 * Compute high frequency value and choose if noise coding should be
337 * activated.
338 */
339 bps1 = bps;
340 if (ahi->channels == 2)
341 bps1 = bps * 1.6;
342 if (sample_rate1 == 44100) {
343 if (bps1 >= 0.61)
344 s->use_noise_coding = 0;
345 else
346 high_freq = high_freq * 0.4;
347 } else if (sample_rate1 == 22050) {
348 if (bps1 >= 1.16)
349 s->use_noise_coding = 0;
350 else if (bps1 >= 0.72)
351 high_freq = high_freq * 0.7;
352 else
353 high_freq = high_freq * 0.6;
354 } else if (sample_rate1 == 16000) {
355 if (bps > 0.5)
356 high_freq = high_freq * 0.5;
357 else
358 high_freq = high_freq * 0.3;
359 } else if (sample_rate1 == 11025) {
360 high_freq = high_freq * 0.7;
361 } else if (sample_rate1 == 8000) {
362 if (bps <= 0.625) {
363 high_freq = high_freq * 0.5;
364 } else if (bps > 0.75) {
365 s->use_noise_coding = 0;
366 } else {
367 high_freq = high_freq * 0.65;
368 }
369 } else {
370 if (bps >= 0.8) {
371 high_freq = high_freq * 0.75;
372 } else if (bps >= 0.6) {
373 high_freq = high_freq * 0.6;
374 } else {
375 high_freq = high_freq * 0.5;
376 }
377 }
378 PARA_INFO_LOG("channels=%d sample_rate=%d "
379 "bitrate=%d block_align=%d\n",
380 ahi->channels, ahi->sample_rate,
381 ahi->bit_rate, ahi->block_align);
382 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
383 "high_freq=%f bitoffset=%d\n",
384 s->frame_len, bps, bps1,
385 high_freq, s->byte_offset_bits);
386 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
387 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
388
389 compute_scale_factor_band_sizes(s, high_freq);
390 /* init MDCT windows : simple sinus window */
391 for (i = 0; i < s->nb_block_sizes; i++) {
392 int n;
393 n = 1 << (s->frame_len_bits - i);
394 sine_window_init(ff_sine_windows[s->frame_len_bits - i - 7], n);
395 s->windows[i] = ff_sine_windows[s->frame_len_bits - i - 7];
396 }
397
398 s->reset_block_lengths = 1;
399
400 if (s->use_noise_coding) {
401 /* init the noise generator */
402 if (s->use_exp_vlc)
403 s->noise_mult = 0.02;
404 else
405 s->noise_mult = 0.04;
406
407 {
408 unsigned int seed;
409 float norm;
410 seed = 1;
411 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
412 for (i = 0; i < NOISE_TAB_SIZE; i++) {
413 seed = seed * 314159 + 1;
414 s->noise_table[i] = (float) ((int) seed) * norm;
415 }
416 }
417 }
418
419 /* choose the VLC tables for the coefficients */
420 coef_vlc_table = 2;
421 if (ahi->sample_rate >= 32000) {
422 if (bps1 < 0.72)
423 coef_vlc_table = 0;
424 else if (bps1 < 1.16)
425 coef_vlc_table = 1;
426 }
427 s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
428 s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
429 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
430 &s->int_table[0], s->coef_vlcs[0]);
431 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
432 &s->int_table[1], s->coef_vlcs[1]);
433 return 0;
434 }
435
436 static void wma_lsp_to_curve_init(struct private_wmadec_data *s, int frame_len)
437 {
438 float wdel, a, b;
439 int i, e, m;
440
441 wdel = M_PI / frame_len;
442 for (i = 0; i < frame_len; i++)
443 s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
444
445 /* tables for x^-0.25 computation */
446 for (i = 0; i < 256; i++) {
447 e = i - 126;
448 s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
449 }
450
451 /* These two tables are needed to avoid two operations in pow_m1_4. */
452 b = 1.0;
453 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
454 m = (1 << LSP_POW_BITS) + i;
455 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
456 a = pow(a, -0.25);
457 s->lsp_pow_m_table1[i] = 2 * a - b;
458 s->lsp_pow_m_table2[i] = b - a;
459 b = a;
460 }
461 }
462
463 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
464 {
465 struct private_wmadec_data *s;
466 int ret, i;
467
468 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
469 s = para_calloc(sizeof(*s));
470 ret = read_asf_header(initial_buf, len, &s->ahi);
471 if (ret <= 0) {
472 free(s);
473 return ret;
474 }
475
476 s->use_exp_vlc = s->ahi.flags2 & 0x0001;
477 s->use_bit_reservoir = s->ahi.flags2 & 0x0002;
478 s->use_variable_block_len = s->ahi.flags2 & 0x0004;
479
480 ret = wma_init(s, s->ahi.flags2, &s->ahi);
481 if (ret < 0)
482 return ret;
483 /* init MDCT */
484 for (i = 0; i < s->nb_block_sizes; i++) {
485 ret = imdct_init(s->frame_len_bits - i + 1, &s->mdct_ctx[i]);
486 if (ret < 0)
487 return ret;
488 }
489 if (s->use_noise_coding) {
490 PARA_INFO_LOG("using noise coding\n");
491 init_vlc(&s->hgain_vlc, HGAINVLCBITS,
492 sizeof(ff_wma_hgain_huffbits), ff_wma_hgain_huffbits,
493 1, 1, ff_wma_hgain_huffcodes, 2, 2);
494 }
495
496 if (s->use_exp_vlc) {
497 PARA_INFO_LOG("using exp_vlc\n");
498 init_vlc(&s->exp_vlc, EXPVLCBITS,
499 sizeof(ff_wma_scale_huffbits), ff_wma_scale_huffbits,
500 1, 1, ff_wma_scale_huffcodes, 4, 4);
501 } else {
502 PARA_INFO_LOG("using curve\n");
503 wma_lsp_to_curve_init(s, s->frame_len);
504 }
505 *result = s;
506 return s->ahi.header_len;
507 }
508
509 /**
510 * compute x^-0.25 with an exponent and mantissa table. We use linear
511 * interpolation to reduce the mantissa table size at a small speed
512 * expense (linear interpolation approximately doubles the number of
513 * bits of precision).
514 */
515 static inline float pow_m1_4(struct private_wmadec_data *s, float x)
516 {
517 union {
518 float f;
519 unsigned int v;
520 } u, t;
521 unsigned int e, m;
522 float a, b;
523
524 u.f = x;
525 e = u.v >> 23;
526 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
527 /* build interpolation scale: 1 <= t < 2. */
528 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
529 a = s->lsp_pow_m_table1[m];
530 b = s->lsp_pow_m_table2[m];
531 return s->lsp_pow_e_table[e] * (a + b * t.f);
532 }
533
534 static void wma_lsp_to_curve(struct private_wmadec_data *s,
535 float *out, float *val_max_ptr, int n, float *lsp)
536 {
537 int i, j;
538 float p, q, w, v, val_max;
539
540 val_max = 0;
541 for (i = 0; i < n; i++) {
542 p = 0.5f;
543 q = 0.5f;
544 w = s->lsp_cos_table[i];
545 for (j = 1; j < NB_LSP_COEFS; j += 2) {
546 q *= w - lsp[j - 1];
547 p *= w - lsp[j];
548 }
549 p *= p * (2.0f - w);
550 q *= q * (2.0f + w);
551 v = p + q;
552 v = pow_m1_4(s, v);
553 if (v > val_max)
554 val_max = v;
555 out[i] = v;
556 }
557 *val_max_ptr = val_max;
558 }
559
560 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
561 static void decode_exp_lsp(struct private_wmadec_data *s, int ch)
562 {
563 float lsp_coefs[NB_LSP_COEFS];
564 int val, i;
565
566 for (i = 0; i < NB_LSP_COEFS; i++) {
567 if (i == 0 || i >= 8)
568 val = get_bits(&s->gb, 3);
569 else
570 val = get_bits(&s->gb, 4);
571 lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
572 }
573
574 wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
575 s->block_len, lsp_coefs);
576 }
577
578 /*
579 * Parse a vlc code, faster then get_vlc().
580 *
581 * \param bits The number of bits which will be read at once, must be
582 * identical to nb_bits in init_vlc()
583 *
584 * \param max_depth The number of times bits bits must be read to completely
585 * read the longest vlc code = (max_vlc_length + bits - 1) / bits.
586 */
587 static int get_vlc2(struct getbit_context *s, VLC_TYPE(*table)[2],
588 int bits, int max_depth)
589 {
590 int code;
591
592 OPEN_READER(re, s)
593 UPDATE_CACHE(re, s)
594 GET_VLC(code, re, s, table, bits, max_depth)
595 CLOSE_READER(re, s)
596 return code;
597 }
598
599 /* Decode exponents coded with VLC codes. */
600 static int decode_exp_vlc(struct private_wmadec_data *s, int ch)
601 {
602 int last_exp, n, code;
603 const uint16_t *ptr, *band_ptr;
604 float v, *q, max_scale, *q_end;
605
606 band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
607 ptr = band_ptr;
608 q = s->exponents[ch];
609 q_end = q + s->block_len;
610 max_scale = 0;
611 last_exp = 36;
612
613 while (q < q_end) {
614 code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
615 if (code < 0)
616 return -1;
617 /* NOTE: this offset is the same as MPEG4 AAC ! */
618 last_exp += code - 60;
619 /* XXX: use a table */
620 v = pow(10, last_exp * (1.0 / 16.0));
621 if (v > max_scale)
622 max_scale = v;
623 n = *ptr++;
624 do {
625 *q++ = v;
626 } while (--n);
627 }
628 s->max_exponent[ch] = max_scale;
629 return 0;
630 }
631
632 /* compute src0 * src1 + src2 */
633 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
634 const float *src2, int len)
635 {
636 int i;
637
638 for (i = 0; i < len; i++)
639 dst[i] = src0[i] * src1[i] + src2[i];
640 }
641
642 static inline void vector_mult_reverse(float *dst, const float *src0,
643 const float *src1, int len)
644 {
645 int i;
646
647 src1 += len - 1;
648 for (i = 0; i < len; i++)
649 dst[i] = src0[i] * src1[-i];
650 }
651
652 /**
653 * Apply MDCT window and add into output.
654 *
655 * We ensure that when the windows overlap their squared sum
656 * is always 1 (MDCT reconstruction rule).
657 */
658 static void wma_window(struct private_wmadec_data *s, float *out)
659 {
660 float *in = s->output;
661 int block_len, bsize, n;
662
663 /* left part */
664 if (s->block_len_bits <= s->prev_block_len_bits) {
665 block_len = s->block_len;
666 bsize = s->frame_len_bits - s->block_len_bits;
667 vector_mult_add(out, in, s->windows[bsize], out, block_len);
668 } else {
669 block_len = 1 << s->prev_block_len_bits;
670 n = (s->block_len - block_len) / 2;
671 bsize = s->frame_len_bits - s->prev_block_len_bits;
672 vector_mult_add(out + n, in + n, s->windows[bsize], out + n,
673 block_len);
674 memcpy(out + n + block_len, in + n + block_len,
675 n * sizeof(float));
676 }
677 out += s->block_len;
678 in += s->block_len;
679 /* right part */
680 if (s->block_len_bits <= s->next_block_len_bits) {
681 block_len = s->block_len;
682 bsize = s->frame_len_bits - s->block_len_bits;
683 vector_mult_reverse(out, in, s->windows[bsize], block_len);
684 } else {
685 block_len = 1 << s->next_block_len_bits;
686 n = (s->block_len - block_len) / 2;
687 bsize = s->frame_len_bits - s->next_block_len_bits;
688 memcpy(out, in, n * sizeof(float));
689 vector_mult_reverse(out + n, in + n, s->windows[bsize],
690 block_len);
691 memset(out + n + block_len, 0, n * sizeof(float));
692 }
693 }
694
695 static int wma_total_gain_to_bits(int total_gain)
696 {
697 if (total_gain < 15)
698 return 13;
699 else if (total_gain < 32)
700 return 12;
701 else if (total_gain < 40)
702 return 11;
703 else if (total_gain < 45)
704 return 10;
705 else
706 return 9;
707 }
708
709 /**
710 * @return 0 if OK. 1 if last block of frame. return -1 if
711 * unrecorrable error.
712 */
713 static int wma_decode_block(struct private_wmadec_data *s)
714 {
715 int n, v, ch, code, bsize;
716 int coef_nb_bits, total_gain;
717 int nb_coefs[MAX_CHANNELS];
718 float mdct_norm;
719
720 /* compute current block length */
721 if (s->use_variable_block_len) {
722 n = wma_log2(s->nb_block_sizes - 1) + 1;
723
724 if (s->reset_block_lengths) {
725 s->reset_block_lengths = 0;
726 v = get_bits(&s->gb, n);
727 if (v >= s->nb_block_sizes)
728 return -1;
729 s->prev_block_len_bits = s->frame_len_bits - v;
730 v = get_bits(&s->gb, n);
731 if (v >= s->nb_block_sizes)
732 return -1;
733 s->block_len_bits = s->frame_len_bits - v;
734 } else {
735 /* update block lengths */
736 s->prev_block_len_bits = s->block_len_bits;
737 s->block_len_bits = s->next_block_len_bits;
738 }
739 v = get_bits(&s->gb, n);
740 if (v >= s->nb_block_sizes)
741 return -1;
742 s->next_block_len_bits = s->frame_len_bits - v;
743 } else {
744 /* fixed block len */
745 s->next_block_len_bits = s->frame_len_bits;
746 s->prev_block_len_bits = s->frame_len_bits;
747 s->block_len_bits = s->frame_len_bits;
748 }
749
750 /* now check if the block length is coherent with the frame length */
751 s->block_len = 1 << s->block_len_bits;
752 if ((s->block_pos + s->block_len) > s->frame_len)
753 return -E_INCOHERENT_BLOCK_LEN;
754
755 if (s->ahi.channels == 2) {
756 s->ms_stereo = get_bits1(&s->gb);
757 }
758 v = 0;
759 for (ch = 0; ch < s->ahi.channels; ch++) {
760 int a = get_bits1(&s->gb);
761 s->channel_coded[ch] = a;
762 v |= a;
763 }
764
765 bsize = s->frame_len_bits - s->block_len_bits;
766
767 /* if no channel coded, no need to go further */
768 /* XXX: fix potential framing problems */
769 if (!v)
770 goto next;
771
772 /* read total gain and extract corresponding number of bits for
773 coef escape coding */
774 total_gain = 1;
775 for (;;) {
776 int a = get_bits(&s->gb, 7);
777 total_gain += a;
778 if (a != 127)
779 break;
780 }
781
782 coef_nb_bits = wma_total_gain_to_bits(total_gain);
783
784 /* compute number of coefficients */
785 n = s->coefs_end[bsize] - s->coefs_start;
786 for (ch = 0; ch < s->ahi.channels; ch++)
787 nb_coefs[ch] = n;
788
789 /* complex coding */
790 if (s->use_noise_coding) {
791 for (ch = 0; ch < s->ahi.channels; ch++) {
792 if (s->channel_coded[ch]) {
793 int i, m, a;
794 m = s->exponent_high_sizes[bsize];
795 for (i = 0; i < m; i++) {
796 a = get_bits1(&s->gb);
797 s->high_band_coded[ch][i] = a;
798 /* if noise coding, the coefficients are not transmitted */
799 if (a)
800 nb_coefs[ch] -=
801 s->
802 exponent_high_bands[bsize]
803 [i];
804 }
805 }
806 }
807 for (ch = 0; ch < s->ahi.channels; ch++) {
808 if (s->channel_coded[ch]) {
809 int i, val;
810
811 n = s->exponent_high_sizes[bsize];
812 val = (int) 0x80000000;
813 for (i = 0; i < n; i++) {
814 if (s->high_band_coded[ch][i]) {
815 if (val == (int) 0x80000000) {
816 val =
817 get_bits(&s->gb,
818 7) - 19;
819 } else {
820 code =
821 get_vlc2(&s->gb,
822 s->
823 hgain_vlc.
824 table,
825 HGAINVLCBITS,
826 HGAINMAX);
827 if (code < 0)
828 return -1;
829 val += code - 18;
830 }
831 s->high_band_values[ch][i] =
832 val;
833 }
834 }
835 }
836 }
837 }
838
839 /* exponents can be reused in short blocks. */
840 if ((s->block_len_bits == s->frame_len_bits) || get_bits1(&s->gb)) {
841 for (ch = 0; ch < s->ahi.channels; ch++) {
842 if (s->channel_coded[ch]) {
843 if (s->use_exp_vlc) {
844 if (decode_exp_vlc(s, ch) < 0)
845 return -1;
846 } else {
847 decode_exp_lsp(s, ch);
848 }
849 s->exponents_bsize[ch] = bsize;
850 }
851 }
852 }
853
854 /* parse spectral coefficients : just RLE encoding */
855 for (ch = 0; ch < s->ahi.channels; ch++) {
856 if (s->channel_coded[ch]) {
857 struct vlc *coef_vlc;
858 int level, run, sign, tindex;
859 int16_t *ptr, *eptr;
860 const uint16_t *level_table, *run_table;
861
862 /* special VLC tables are used for ms stereo because
863 there is potentially less energy there */
864 tindex = (ch == 1 && s->ms_stereo);
865 coef_vlc = &s->coef_vlc[tindex];
866 run_table = s->run_table[tindex];
867 level_table = s->level_table[tindex];
868 /* XXX: optimize */
869 ptr = &s->coefs1[ch][0];
870 eptr = ptr + nb_coefs[ch];
871 memset(ptr, 0, s->block_len * sizeof(int16_t));
872 for (;;) {
873 code =
874 get_vlc2(&s->gb, coef_vlc->table, VLCBITS,
875 VLCMAX);
876 if (code < 0)
877 return -1;
878 if (code == 1) {
879 /* EOB */
880 break;
881 } else if (code == 0) {
882 /* escape */
883 level = get_bits(&s->gb, coef_nb_bits);
884 /* NOTE: this is rather suboptimal. reading
885 block_len_bits would be better */
886 run =
887 get_bits(&s->gb, s->frame_len_bits);
888 } else {
889 /* normal code */
890 run = run_table[code];
891 level = level_table[code];
892 }
893 sign = get_bits1(&s->gb);
894 if (!sign)
895 level = -level;
896 ptr += run;
897 if (ptr >= eptr) {
898 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
899 break;
900 }
901 *ptr++ = level;
902 /* NOTE: EOB can be omitted */
903 if (ptr >= eptr)
904 break;
905 }
906 }
907 }
908
909 /* normalize */
910 {
911 int n4 = s->block_len / 2;
912 mdct_norm = 1.0 / (float) n4;
913 }
914
915 /* finally compute the MDCT coefficients */
916 for (ch = 0; ch < s->ahi.channels; ch++) {
917 if (s->channel_coded[ch]) {
918 int16_t *coefs1;
919 float *coefs, *exponents, mult, mult1, noise;
920 int i, j, n1, last_high_band, esize;
921 float exp_power[HIGH_BAND_MAX_SIZE];
922
923 coefs1 = s->coefs1[ch];
924 exponents = s->exponents[ch];
925 esize = s->exponents_bsize[ch];
926 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
927 mult *= mdct_norm;
928 coefs = s->coefs[ch];
929 if (s->use_noise_coding) {
930 mult1 = mult;
931 /* very low freqs : noise */
932 for (i = 0; i < s->coefs_start; i++) {
933 *coefs++ =
934 s->noise_table[s->noise_index] *
935 exponents[i << bsize >> esize] *
936 mult1;
937 s->noise_index =
938 (s->noise_index +
939 1) & (NOISE_TAB_SIZE - 1);
940 }
941
942 n1 = s->exponent_high_sizes[bsize];
943
944 /* compute power of high bands */
945 exponents = s->exponents[ch] +
946 (s->high_band_start[bsize] << bsize);
947 last_high_band = 0; /* avoid warning */
948 for (j = 0; j < n1; j++) {
949 n = s->exponent_high_bands[s->
950 frame_len_bits
951 -
952 s->
953 block_len_bits]
954 [j];
955 if (s->high_band_coded[ch][j]) {
956 float e2, val;
957 e2 = 0;
958 for (i = 0; i < n; i++) {
959 val = exponents[i << bsize
960 >> esize];
961 e2 += val * val;
962 }
963 exp_power[j] = e2 / n;
964 last_high_band = j;
965 }
966 exponents += n << bsize;
967 }
968
969 /* main freqs and high freqs */
970 exponents =
971 s->exponents[ch] +
972 (s->coefs_start << bsize);
973 for (j = -1; j < n1; j++) {
974 if (j < 0) {
975 n = s->high_band_start[bsize] -
976 s->coefs_start;
977 } else {
978 n = s->exponent_high_bands[s->
979 frame_len_bits
980 -
981 s->
982 block_len_bits]
983 [j];
984 }
985 if (j >= 0 && s->high_band_coded[ch][j]) {
986 /* use noise with specified power */
987 mult1 =
988 sqrt(exp_power[j] /
989 exp_power
990 [last_high_band]);
991 /* XXX: use a table */
992 mult1 =
993 mult1 * pow(10,
994 s->
995 high_band_values
996 [ch][j] * 0.05);
997 mult1 =
998 mult1 /
999 (s->max_exponent[ch] *
1000 s->noise_mult);
1001 mult1 *= mdct_norm;
1002 for (i = 0; i < n; i++) {
1003 noise =
1004 s->noise_table[s->
1005 noise_index];
1006 s->noise_index =
1007 (s->noise_index +
1008 1) &
1009 (NOISE_TAB_SIZE -
1010 1);
1011 *coefs++ =
1012 noise *
1013 exponents[i << bsize
1014 >> esize]
1015 * mult1;
1016 }
1017 exponents += n << bsize;
1018 } else {
1019 /* coded values + small noise */
1020 for (i = 0; i < n; i++) {
1021 noise =
1022 s->noise_table[s->
1023 noise_index];
1024 s->noise_index =
1025 (s->noise_index +
1026 1) &
1027 (NOISE_TAB_SIZE -
1028 1);
1029 *coefs++ =
1030 ((*coefs1++) +
1031 noise) *
1032 exponents[i << bsize
1033 >> esize]
1034 * mult;
1035 }
1036 exponents += n << bsize;
1037 }
1038 }
1039
1040 /* very high freqs : noise */
1041 n = s->block_len - s->coefs_end[bsize];
1042 mult1 =
1043 mult * exponents[((-1 << bsize)) >> esize];
1044 for (i = 0; i < n; i++) {
1045 *coefs++ =
1046 s->noise_table[s->noise_index] *
1047 mult1;
1048 s->noise_index =
1049 (s->noise_index +
1050 1) & (NOISE_TAB_SIZE - 1);
1051 }
1052 } else {
1053 /* XXX: optimize more */
1054 for (i = 0; i < s->coefs_start; i++)
1055 *coefs++ = 0.0;
1056 n = nb_coefs[ch];
1057 for (i = 0; i < n; i++) {
1058 *coefs++ =
1059 coefs1[i] *
1060 exponents[i << bsize >> esize] *
1061 mult;
1062 }
1063 n = s->block_len - s->coefs_end[bsize];
1064 for (i = 0; i < n; i++)
1065 *coefs++ = 0.0;
1066 }
1067 }
1068 }
1069
1070 if (s->ms_stereo && s->channel_coded[1]) {
1071 float a, b;
1072 int i;
1073
1074 /*
1075 * Nominal case for ms stereo: we do it before mdct.
1076 *
1077 * No need to optimize this case because it should almost never
1078 * happen.
1079 */
1080 if (!s->channel_coded[0]) {
1081 PARA_NOTICE_LOG("rare ms-stereo\n");
1082 memset(s->coefs[0], 0, sizeof(float) * s->block_len);
1083 s->channel_coded[0] = 1;
1084 }
1085 for (i = 0; i < s->block_len; i++) {
1086 a = s->coefs[0][i];
1087 b = s->coefs[1][i];
1088 s->coefs[0][i] = a + b;
1089 s->coefs[1][i] = a - b;
1090 }
1091 }
1092
1093 next:
1094 for (ch = 0; ch < s->ahi.channels; ch++) {
1095 int n4, index;
1096
1097 n = s->block_len;
1098 n4 = s->block_len / 2;
1099 if (s->channel_coded[ch])
1100 imdct(s->mdct_ctx[bsize], s->output, s->coefs[ch]);
1101 else if (!(s->ms_stereo && ch == 1))
1102 memset(s->output, 0, sizeof(s->output));
1103
1104 /* multiply by the window and add in the frame */
1105 index = (s->frame_len / 2) + s->block_pos - n4;
1106 wma_window(s, &s->frame_out[ch][index]);
1107 }
1108
1109 /* update block number */
1110 s->block_pos += s->block_len;
1111 if (s->block_pos >= s->frame_len)
1112 return 1;
1113 else
1114 return 0;
1115 }
1116
1117 /*
1118 * Clip a signed integer value into the -32768,32767 range.
1119 *
1120 * \param a The value to clip.
1121 *
1122 * \return The clipped value.
1123 */
1124 static inline int16_t av_clip_int16(int a)
1125 {
1126 if ((a + 32768) & ~65535)
1127 return (a >> 31) ^ 32767;
1128 else
1129 return a;
1130 }
1131
1132 /* Decode a frame of frame_len samples. */
1133 static int wma_decode_frame(struct private_wmadec_data *s, int16_t * samples)
1134 {
1135 int ret, i, n, ch, incr;
1136 int16_t *ptr;
1137 float *iptr;
1138
1139 /* read each block */
1140 s->block_pos = 0;
1141 for (;;) {
1142 ret = wma_decode_block(s);
1143 if (ret < 0)
1144 return -1;
1145 if (ret)
1146 break;
1147 }
1148
1149 /* convert frame to integer */
1150 n = s->frame_len;
1151 incr = s->ahi.channels;
1152 for (ch = 0; ch < s->ahi.channels; ch++) {
1153 ptr = samples + ch;
1154 iptr = s->frame_out[ch];
1155
1156 for (i = 0; i < n; i++) {
1157 *ptr = av_clip_int16(lrintf(*iptr++));
1158 ptr += incr;
1159 }
1160 /* prepare for next block */
1161 memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
1162 s->frame_len * sizeof(float));
1163 }
1164 return 0;
1165 }
1166
1167 static int wma_decode_superframe(struct private_wmadec_data *s, void *data,
1168 int *data_size, const uint8_t *buf, int buf_size)
1169 {
1170 int ret, nb_frames, bit_offset, i, pos, len;
1171 uint8_t *q;
1172 int16_t *samples;
1173 static int frame_count;
1174
1175 if (buf_size == 0) {
1176 s->last_superframe_len = 0;
1177 return 0;
1178 }
1179 if (buf_size < s->ahi.block_align)
1180 return 0;
1181 buf_size = s->ahi.block_align;
1182 samples = data;
1183 init_get_bits(&s->gb, buf, buf_size * 8);
1184 if (s->use_bit_reservoir) {
1185 /* read super frame header */
1186 skip_bits(&s->gb, 4); /* super frame index */
1187 nb_frames = get_bits(&s->gb, 4) - 1;
1188 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1189 ret = -E_WMA_OUTPUT_SPACE;
1190 if ((nb_frames + 1) * s->ahi.channels * s->frame_len
1191 * sizeof(int16_t) > *data_size)
1192 goto fail;
1193
1194 bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
1195
1196 if (s->last_superframe_len > 0) {
1197 /* add bit_offset bits to last frame */
1198 ret = -E_WMA_BAD_SUPERFRAME;
1199 if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
1200 MAX_CODED_SUPERFRAME_SIZE)
1201 goto fail;
1202 q = s->last_superframe + s->last_superframe_len;
1203 len = bit_offset;
1204 while (len > 7) {
1205 *q++ = get_bits(&s->gb, 8);
1206 len -= 8;
1207 }
1208 if (len > 0) {
1209 *q++ = get_bits(&s->gb, len) << (8 - len);
1210 }
1211
1212 /* XXX: bit_offset bits into last frame */
1213 init_get_bits(&s->gb, s->last_superframe,
1214 MAX_CODED_SUPERFRAME_SIZE * 8);
1215 /* skip unused bits */
1216 if (s->last_bitoffset > 0)
1217 skip_bits(&s->gb, s->last_bitoffset);
1218 /*
1219 * This frame is stored in the last superframe and in
1220 * the current one.
1221 */
1222 ret = -E_WMA_DECODE;
1223 if (wma_decode_frame(s, samples) < 0)
1224 goto fail;
1225 frame_count++;
1226 samples += s->ahi.channels * s->frame_len;
1227 }
1228
1229 /* read each frame starting from bit_offset */
1230 pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
1231 init_get_bits(&s->gb, buf + (pos >> 3),
1232 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)) * 8);
1233 len = pos & 7;
1234 if (len > 0)
1235 skip_bits(&s->gb, len);
1236
1237 s->reset_block_lengths = 1;
1238 for (i = 0; i < nb_frames; i++) {
1239 ret = -E_WMA_DECODE;
1240 if (wma_decode_frame(s, samples) < 0)
1241 goto fail;
1242 frame_count++;
1243 samples += s->ahi.channels * s->frame_len;
1244 }
1245
1246 /* we copy the end of the frame in the last frame buffer */
1247 pos = get_bits_count(&s->gb) +
1248 ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
1249 s->last_bitoffset = pos & 7;
1250 pos >>= 3;
1251 len = buf_size - pos;
1252 ret = -E_WMA_BAD_SUPERFRAME;
1253 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
1254 goto fail;
1255 }
1256 s->last_superframe_len = len;
1257 memcpy(s->last_superframe, buf + pos, len);
1258 } else {
1259 PARA_DEBUG_LOG("not using bit reservoir\n");
1260 ret = -E_WMA_OUTPUT_SPACE;
1261 if (s->ahi.channels * s->frame_len * sizeof(int16_t) > *data_size)
1262 goto fail;
1263 /* single frame decode */
1264 ret = -E_WMA_DECODE;
1265 if (wma_decode_frame(s, samples) < 0)
1266 goto fail;
1267 frame_count++;
1268 samples += s->ahi.channels * s->frame_len;
1269 }
1270 PARA_DEBUG_LOG("frame_count: %d frame_len: %d, block_len: %d, "
1271 "outbytes: %d, eaten: %d\n",
1272 frame_count, s->frame_len, s->block_len,
1273 (int8_t *) samples - (int8_t *) data, s->ahi.block_align);
1274 *data_size = (int8_t *)samples - (int8_t *)data;
1275 return s->ahi.block_align;
1276 fail:
1277 /* reset the bit reservoir on errors */
1278 s->last_superframe_len = 0;
1279 return ret;
1280 }
1281
1282 static ssize_t wmadec_convert(char *inbuffer, size_t len,
1283 struct filter_node *fn)
1284 {
1285 int ret, out_size = fn->bufsize - fn->loaded;
1286 struct private_wmadec_data *pwd = fn->private_data;
1287
1288 if (out_size < 128 * 1024)
1289 return 0;
1290 if (!pwd) {
1291 ret = wma_decode_init(inbuffer, len, &pwd);
1292 if (ret <= 0)
1293 return ret;
1294 fn->private_data = pwd;
1295 fn->fc->channels = pwd->ahi.channels;
1296 fn->fc->samplerate = pwd->ahi.sample_rate;
1297 return pwd->ahi.header_len;
1298 }
1299 /* skip 31 bytes */
1300 if (len <= WMA_FRAME_SKIP + pwd->ahi.block_align)
1301 return 0;
1302 ret = wma_decode_superframe(pwd, fn->buf + fn->loaded,
1303 &out_size, (uint8_t *)inbuffer + WMA_FRAME_SKIP,
1304 len - WMA_FRAME_SKIP);
1305 if (ret < 0)
1306 return ret;
1307 fn->loaded += out_size;
1308 return ret + WMA_FRAME_SKIP;
1309 }
1310
1311 static void wmadec_close(struct filter_node *fn)
1312 {
1313 struct private_wmadec_data *pwd = fn->private_data;
1314 if (!pwd)
1315 return;
1316 wmadec_cleanup(pwd);
1317 free(fn->buf);
1318 fn->buf = NULL;
1319 free(fn->private_data);
1320 fn->private_data = NULL;
1321 }
1322
1323 static void wmadec_open(struct filter_node *fn)
1324 {
1325 fn->bufsize = 1024 * 1024;
1326 fn->buf = para_malloc(fn->bufsize);
1327 fn->private_data = NULL;
1328 fn->loaded = 0;
1329 }
1330
1331 /**
1332 * The init function of the wma decoder.
1333 *
1334 * \param f Its fields are filled in by the function.
1335 */
1336 void wmadec_filter_init(struct filter *f)
1337 {
1338 f->open = wmadec_open;
1339 f->close = wmadec_close;
1340 f->convert = wmadec_convert;
1341 }