2 * WMA compatible decoder
4 * Extracted 2009 from the mplayer source code 2009-02-10.
6 * Copyright (c) 2002 The FFmpeg Project
8 * Licensed under the GNU Lesser General Public License.
9 * For licencing details see COPYING.LIB.
12 /** \file wmadec_filter.c paraslash's WMA decoder. */
15 * This decoder handles Microsoft Windows Media Audio data version 2.
18 #define _XOPEN_SOURCE 600
35 #include "bitstream.h"
42 #define BLOCK_MIN_BITS 7
43 #define BLOCK_MAX_BITS 11
44 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
46 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
48 /* XXX: find exact max size */
49 #define HIGH_BAND_MAX_SIZE 16
51 /* XXX: is it a suitable value ? */
52 #define MAX_CODED_SUPERFRAME_SIZE 16384
54 #define MAX_CHANNELS 2
56 #define NOISE_TAB_SIZE 8192
58 #define LSP_POW_BITS 7
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
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];
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];
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 const struct coef_vlc_table *coef_vlcs[2];
88 int frame_len; ///< frame length in samples
89 int frame_len_bits; ///< frame_len = 1 << frame_len_bits
90 int nb_block_sizes; ///< number of block sizes
92 int reset_block_lengths;
93 int block_len_bits; ///< log2 of current block length
94 int next_block_len_bits; ///< log2 of next block length
95 int prev_block_len_bits; ///< log2 of prev block length
96 int block_len; ///< block length in samples
97 int block_pos; ///< current position in frame
98 uint8_t ms_stereo; ///< true if mid/side stereo mode
99 uint8_t channel_coded[MAX_CHANNELS]; ///< true if channel is coded
100 int exponents_bsize[MAX_CHANNELS]; ///< log2 ratio frame/exp. length
101 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
102 float max_exponent[MAX_CHANNELS];
103 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
104 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
105 float output[BLOCK_MAX_SIZE * 2];
106 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
107 float *windows[BLOCK_NB_SIZES];
108 /* output buffer for one frame and the last for IMDCT windowing */
109 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
110 /* last frame info */
111 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
113 int last_superframe_len;
114 float noise_table[NOISE_TAB_SIZE];
116 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
117 /* lsp_to_curve tables */
118 float lsp_cos_table[BLOCK_MAX_SIZE];
119 float lsp_pow_e_table[256];
120 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
121 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
125 #define EXPMAX ((19 + EXPVLCBITS - 1) / EXPVLCBITS)
127 #define HGAINVLCBITS 9
128 #define HGAINMAX ((13 + HGAINVLCBITS - 1) / HGAINVLCBITS)
131 #define VLCMAX ((22 + VLCBITS - 1) / VLCBITS)
133 DECLARE_ALIGNED(16, float, ff_sine_128[128]);
134 DECLARE_ALIGNED(16, float, ff_sine_256[256]);
135 DECLARE_ALIGNED(16, float, ff_sine_512[512]);
136 DECLARE_ALIGNED(16, float, ff_sine_1024[1024]);
137 DECLARE_ALIGNED(16, float, ff_sine_2048[2048]);
138 DECLARE_ALIGNED(16, float, ff_sine_4096[4096]);
140 static float *ff_sine_windows[6] = {
141 ff_sine_128, ff_sine_256, ff_sine_512, ff_sine_1024,
142 ff_sine_2048, ff_sine_4096
145 /* Generate a sine window. */
146 static void sine_window_init(float *window, int n)
150 for (i = 0; i < n; i++)
151 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
154 static void wmadec_cleanup(struct private_wmadec_data *pwd)
158 for (i = 0; i < pwd->nb_block_sizes; i++)
159 imdct_end(pwd->mdct_ctx[i]);
160 if (pwd->use_exp_vlc)
161 free_vlc(&pwd->exp_vlc);
162 if (pwd->use_noise_coding)
163 free_vlc(&pwd->hgain_vlc);
164 for (i = 0; i < 2; i++) {
165 free_vlc(&pwd->coef_vlc[i]);
166 free(pwd->run_table[i]);
167 free(pwd->level_table[i]);
171 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
172 uint16_t **plevel_table, const struct coef_vlc_table *vlc_table)
174 int n = vlc_table->n;
175 const uint8_t *table_bits = vlc_table->huffbits;
176 const uint32_t *table_codes = vlc_table->huffcodes;
177 const uint16_t *levels_table = vlc_table->levels;
178 uint16_t *run_table, *level_table;
179 int i, l, j, k, level;
181 PARA_ERROR_LOG("n: %d\n", n);
182 init_vlc(vlc, VLCBITS, n, table_bits, table_codes, 4);
184 run_table = para_malloc(n * sizeof(uint16_t));
185 level_table = para_malloc(n * sizeof(uint16_t));
190 l = levels_table[k++];
191 for (j = 0; j < l; j++) {
193 level_table[i] = level;
198 *prun_table = run_table;
199 *plevel_table = level_table;
202 /* compute the scale factor band sizes for each MDCT block size */
203 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
206 struct asf_header_info *ahi = &pwd->ahi;
207 int a, b, pos, lpos, k, block_len, i, j, n;
208 const uint8_t *table;
210 pwd->coefs_start = 0;
211 for (k = 0; k < pwd->nb_block_sizes; k++) {
212 block_len = pwd->frame_len >> k;
215 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
217 if (ahi->sample_rate >= 44100)
218 table = exponent_band_44100[a];
219 else if (ahi->sample_rate >= 32000)
220 table = exponent_band_32000[a];
221 else if (ahi->sample_rate >= 22050)
222 table = exponent_band_22050[a];
226 for (i = 0; i < n; i++)
227 pwd->exponent_bands[k][i] = table[i];
228 pwd->exponent_sizes[k] = n;
232 for (i = 0; i < 25; i++) {
233 a = wma_critical_freqs[i];
234 b = ahi->sample_rate;
235 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
240 pwd->exponent_bands[k][j++] = pos - lpos;
241 if (pos >= block_len)
245 pwd->exponent_sizes[k] = j;
248 /* max number of coefs */
249 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
250 /* high freq computation */
251 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
252 / ahi->sample_rate + 0.5);
253 n = pwd->exponent_sizes[k];
256 for (i = 0; i < n; i++) {
259 pos += pwd->exponent_bands[k][i];
261 if (start < pwd->high_band_start[k])
262 start = pwd->high_band_start[k];
263 if (end > pwd->coefs_end[k])
264 end = pwd->coefs_end[k];
266 pwd->exponent_high_bands[k][j++] = end - start;
268 pwd->exponent_high_sizes[k] = j;
272 static int wma_init(struct private_wmadec_data *pwd)
275 float bps1, high_freq;
279 struct asf_header_info *ahi = &pwd->ahi;
280 int flags2 = ahi->flags2;
282 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
283 || ahi->channels <= 0 || ahi->channels > 8
284 || ahi->bit_rate <= 0)
285 return -E_WMA_BAD_PARAMS;
287 /* compute MDCT block size */
288 if (ahi->sample_rate <= 16000) {
289 pwd->frame_len_bits = 9;
290 } else if (ahi->sample_rate <= 22050) {
291 pwd->frame_len_bits = 10;
293 pwd->frame_len_bits = 11;
295 pwd->frame_len = 1 << pwd->frame_len_bits;
296 if (pwd->use_variable_block_len) {
298 nb = ((flags2 >> 3) & 3) + 1;
299 if ((ahi->bit_rate / ahi->channels) >= 32000)
301 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
304 pwd->nb_block_sizes = nb + 1;
306 pwd->nb_block_sizes = 1;
308 /* init rate dependent parameters */
309 pwd->use_noise_coding = 1;
310 high_freq = ahi->sample_rate * 0.5;
312 /* wma2 rates are normalized */
313 sample_rate1 = ahi->sample_rate;
314 if (sample_rate1 >= 44100)
315 sample_rate1 = 44100;
316 else if (sample_rate1 >= 22050)
317 sample_rate1 = 22050;
318 else if (sample_rate1 >= 16000)
319 sample_rate1 = 16000;
320 else if (sample_rate1 >= 11025)
321 sample_rate1 = 11025;
322 else if (sample_rate1 >= 8000)
325 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
326 pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
328 * Compute high frequency value and choose if noise coding should be
332 if (ahi->channels == 2)
334 if (sample_rate1 == 44100) {
336 pwd->use_noise_coding = 0;
338 high_freq = high_freq * 0.4;
339 } else if (sample_rate1 == 22050) {
341 pwd->use_noise_coding = 0;
342 else if (bps1 >= 0.72)
343 high_freq = high_freq * 0.7;
345 high_freq = high_freq * 0.6;
346 } else if (sample_rate1 == 16000) {
348 high_freq = high_freq * 0.5;
350 high_freq = high_freq * 0.3;
351 } else if (sample_rate1 == 11025) {
352 high_freq = high_freq * 0.7;
353 } else if (sample_rate1 == 8000) {
355 high_freq = high_freq * 0.5;
356 } else if (bps > 0.75) {
357 pwd->use_noise_coding = 0;
359 high_freq = high_freq * 0.65;
363 high_freq = high_freq * 0.75;
364 } else if (bps >= 0.6) {
365 high_freq = high_freq * 0.6;
367 high_freq = high_freq * 0.5;
370 PARA_INFO_LOG("channels=%d sample_rate=%d "
371 "bitrate=%d block_align=%d\n",
372 ahi->channels, ahi->sample_rate,
373 ahi->bit_rate, ahi->block_align);
374 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
375 "high_freq=%f bitoffset=%d\n",
376 pwd->frame_len, bps, bps1,
377 high_freq, pwd->byte_offset_bits);
378 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
379 pwd->use_noise_coding, pwd->use_exp_vlc, pwd->nb_block_sizes);
381 compute_scale_factor_band_sizes(pwd, high_freq);
382 /* init MDCT windows : simple sinus window */
383 for (i = 0; i < pwd->nb_block_sizes; i++) {
385 n = 1 << (pwd->frame_len_bits - i);
386 sine_window_init(ff_sine_windows[pwd->frame_len_bits - i - 7], n);
387 pwd->windows[i] = ff_sine_windows[pwd->frame_len_bits - i - 7];
390 pwd->reset_block_lengths = 1;
392 if (pwd->use_noise_coding) {
393 /* init the noise generator */
394 if (pwd->use_exp_vlc)
395 pwd->noise_mult = 0.02;
397 pwd->noise_mult = 0.04;
403 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
404 for (i = 0; i < NOISE_TAB_SIZE; i++) {
405 seed = seed * 314159 + 1;
406 pwd->noise_table[i] = (float) ((int) seed) * norm;
411 /* choose the VLC tables for the coefficients */
413 if (ahi->sample_rate >= 32000) {
416 else if (bps1 < 1.16)
419 pwd->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
420 pwd->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
421 init_coef_vlc(&pwd->coef_vlc[0], &pwd->run_table[0], &pwd->level_table[0],
423 init_coef_vlc(&pwd->coef_vlc[1], &pwd->run_table[1], &pwd->level_table[1],
428 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd, int frame_len)
433 wdel = M_PI / frame_len;
434 for (i = 0; i < frame_len; i++)
435 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
437 /* tables for x^-0.25 computation */
438 for (i = 0; i < 256; i++) {
440 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
443 /* These two tables are needed to avoid two operations in pow_m1_4. */
445 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
446 m = (1 << LSP_POW_BITS) + i;
447 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
449 pwd->lsp_pow_m_table1[i] = 2 * a - b;
450 pwd->lsp_pow_m_table2[i] = b - a;
455 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
457 struct private_wmadec_data *pwd;
460 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
461 pwd = para_calloc(sizeof(*pwd));
462 ret = read_asf_header(initial_buf, len, &pwd->ahi);
468 pwd->use_exp_vlc = pwd->ahi.flags2 & 0x0001;
469 pwd->use_bit_reservoir = pwd->ahi.flags2 & 0x0002;
470 pwd->use_variable_block_len = pwd->ahi.flags2 & 0x0004;
476 for (i = 0; i < pwd->nb_block_sizes; i++) {
477 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
481 if (pwd->use_noise_coding) {
482 PARA_INFO_LOG("using noise coding\n");
483 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
484 sizeof(ff_wma_hgain_huffbits), ff_wma_hgain_huffbits,
485 ff_wma_hgain_huffcodes, 2);
488 if (pwd->use_exp_vlc) {
489 PARA_INFO_LOG("using exp_vlc\n");
490 init_vlc(&pwd->exp_vlc, EXPVLCBITS,
491 sizeof(ff_wma_scale_huffbits), ff_wma_scale_huffbits,
492 ff_wma_scale_huffcodes, 4);
494 PARA_INFO_LOG("using curve\n");
495 wma_lsp_to_curve_init(pwd, pwd->frame_len);
498 return pwd->ahi.header_len;
502 * compute x^-0.25 with an exponent and mantissa table. We use linear
503 * interpolation to reduce the mantissa table size at a small speed
504 * expense (linear interpolation approximately doubles the number of
505 * bits of precision).
507 static inline float pow_m1_4(struct private_wmadec_data *pwd, float x)
518 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
519 /* build interpolation scale: 1 <= t < 2. */
520 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
521 a = pwd->lsp_pow_m_table1[m];
522 b = pwd->lsp_pow_m_table2[m];
523 return pwd->lsp_pow_e_table[e] * (a + b * t.f);
526 static void wma_lsp_to_curve(struct private_wmadec_data *pwd,
527 float *out, float *val_max_ptr, int n, float *lsp)
530 float p, q, w, v, val_max;
533 for (i = 0; i < n; i++) {
536 w = pwd->lsp_cos_table[i];
537 for (j = 1; j < NB_LSP_COEFS; j += 2) {
544 v = pow_m1_4(pwd, v);
549 *val_max_ptr = val_max;
552 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
553 static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
555 float lsp_coefs[NB_LSP_COEFS];
558 for (i = 0; i < NB_LSP_COEFS; i++) {
559 if (i == 0 || i >= 8)
560 val = get_bits(&pwd->gb, 3);
562 val = get_bits(&pwd->gb, 4);
563 lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
566 wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
567 pwd->block_len, lsp_coefs);
570 /* Decode exponents coded with VLC codes. */
571 static int decode_exp_vlc(struct private_wmadec_data *pwd, int ch)
573 int last_exp, n, code;
574 const uint16_t *ptr, *band_ptr;
575 float v, *q, max_scale, *q_end;
577 band_ptr = pwd->exponent_bands[pwd->frame_len_bits - pwd->block_len_bits];
579 q = pwd->exponents[ch];
580 q_end = q + pwd->block_len;
585 code = get_vlc(&pwd->gb, pwd->exp_vlc.table, EXPVLCBITS, EXPMAX);
588 /* NOTE: this offset is the same as MPEG4 AAC ! */
589 last_exp += code - 60;
590 /* XXX: use a table */
591 v = pow(10, last_exp * (1.0 / 16.0));
599 pwd->max_exponent[ch] = max_scale;
603 /* compute src0 * src1 + src2 */
604 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
605 const float *src2, int len)
609 for (i = 0; i < len; i++)
610 dst[i] = src0[i] * src1[i] + src2[i];
613 static inline void vector_mult_reverse(float *dst, const float *src0,
614 const float *src1, int len)
619 for (i = 0; i < len; i++)
620 dst[i] = src0[i] * src1[-i];
624 * Apply MDCT window and add into output.
626 * We ensure that when the windows overlap their squared sum
627 * is always 1 (MDCT reconstruction rule).
629 static void wma_window(struct private_wmadec_data *pwd, float *out)
631 float *in = pwd->output;
632 int block_len, bsize, n;
635 if (pwd->block_len_bits <= pwd->prev_block_len_bits) {
636 block_len = pwd->block_len;
637 bsize = pwd->frame_len_bits - pwd->block_len_bits;
638 vector_mult_add(out, in, pwd->windows[bsize], out, block_len);
640 block_len = 1 << pwd->prev_block_len_bits;
641 n = (pwd->block_len - block_len) / 2;
642 bsize = pwd->frame_len_bits - pwd->prev_block_len_bits;
643 vector_mult_add(out + n, in + n, pwd->windows[bsize], out + n,
645 memcpy(out + n + block_len, in + n + block_len,
648 out += pwd->block_len;
649 in += pwd->block_len;
651 if (pwd->block_len_bits <= pwd->next_block_len_bits) {
652 block_len = pwd->block_len;
653 bsize = pwd->frame_len_bits - pwd->block_len_bits;
654 vector_mult_reverse(out, in, pwd->windows[bsize], block_len);
656 block_len = 1 << pwd->next_block_len_bits;
657 n = (pwd->block_len - block_len) / 2;
658 bsize = pwd->frame_len_bits - pwd->next_block_len_bits;
659 memcpy(out, in, n * sizeof(float));
660 vector_mult_reverse(out + n, in + n, pwd->windows[bsize],
662 memset(out + n + block_len, 0, n * sizeof(float));
666 static int wma_total_gain_to_bits(int total_gain)
670 else if (total_gain < 32)
672 else if (total_gain < 40)
674 else if (total_gain < 45)
681 * @return 0 if OK. 1 if last block of frame. return -1 if
682 * unrecorrable error.
684 static int wma_decode_block(struct private_wmadec_data *pwd)
686 int n, v, ch, code, bsize;
687 int coef_nb_bits, total_gain;
688 int nb_coefs[MAX_CHANNELS];
691 /* compute current block length */
692 if (pwd->use_variable_block_len) {
693 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
695 if (pwd->reset_block_lengths) {
696 pwd->reset_block_lengths = 0;
697 v = get_bits(&pwd->gb, n);
698 if (v >= pwd->nb_block_sizes)
700 pwd->prev_block_len_bits = pwd->frame_len_bits - v;
701 v = get_bits(&pwd->gb, n);
702 if (v >= pwd->nb_block_sizes)
704 pwd->block_len_bits = pwd->frame_len_bits - v;
706 /* update block lengths */
707 pwd->prev_block_len_bits = pwd->block_len_bits;
708 pwd->block_len_bits = pwd->next_block_len_bits;
710 v = get_bits(&pwd->gb, n);
711 if (v >= pwd->nb_block_sizes)
713 pwd->next_block_len_bits = pwd->frame_len_bits - v;
715 /* fixed block len */
716 pwd->next_block_len_bits = pwd->frame_len_bits;
717 pwd->prev_block_len_bits = pwd->frame_len_bits;
718 pwd->block_len_bits = pwd->frame_len_bits;
721 /* now check if the block length is coherent with the frame length */
722 pwd->block_len = 1 << pwd->block_len_bits;
723 if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
724 return -E_INCOHERENT_BLOCK_LEN;
726 if (pwd->ahi.channels == 2)
727 pwd->ms_stereo = get_bit(&pwd->gb);
729 for (ch = 0; ch < pwd->ahi.channels; ch++) {
730 int a = get_bit(&pwd->gb);
731 pwd->channel_coded[ch] = a;
735 bsize = pwd->frame_len_bits - pwd->block_len_bits;
737 /* if no channel coded, no need to go further */
738 /* XXX: fix potential framing problems */
742 /* read total gain and extract corresponding number of bits for
743 coef escape coding */
746 int a = get_bits(&pwd->gb, 7);
752 coef_nb_bits = wma_total_gain_to_bits(total_gain);
754 /* compute number of coefficients */
755 n = pwd->coefs_end[bsize] - pwd->coefs_start;
756 for (ch = 0; ch < pwd->ahi.channels; ch++)
760 if (pwd->use_noise_coding) {
761 for (ch = 0; ch < pwd->ahi.channels; ch++) {
762 if (pwd->channel_coded[ch]) {
764 m = pwd->exponent_high_sizes[bsize];
765 for (i = 0; i < m; i++) {
766 a = get_bit(&pwd->gb);
767 pwd->high_band_coded[ch][i] = a;
768 /* if noise coding, the coefficients are not transmitted */
772 exponent_high_bands[bsize]
777 for (ch = 0; ch < pwd->ahi.channels; ch++) {
778 if (pwd->channel_coded[ch]) {
781 n = pwd->exponent_high_sizes[bsize];
782 val = (int) 0x80000000;
783 for (i = 0; i < n; i++) {
784 if (pwd->high_band_coded[ch][i]) {
785 if (val == (int) 0x80000000) {
801 pwd->high_band_values[ch][i] =
809 /* exponents can be reused in short blocks. */
810 if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
811 for (ch = 0; ch < pwd->ahi.channels; ch++) {
812 if (pwd->channel_coded[ch]) {
813 if (pwd->use_exp_vlc) {
814 if (decode_exp_vlc(pwd, ch) < 0)
817 decode_exp_lsp(pwd, ch);
819 pwd->exponents_bsize[ch] = bsize;
824 /* parse spectral coefficients : just RLE encoding */
825 for (ch = 0; ch < pwd->ahi.channels; ch++) {
826 struct vlc *coef_vlc;
827 int level, run, tindex;
829 const uint16_t *level_table, *run_table;
831 if (!pwd->channel_coded[ch])
834 * special VLC tables are used for ms stereo because there is
835 * potentially less energy there
837 tindex = (ch == 1 && pwd->ms_stereo);
838 coef_vlc = &pwd->coef_vlc[tindex];
839 run_table = pwd->run_table[tindex];
840 level_table = pwd->level_table[tindex];
842 ptr = &pwd->coefs1[ch][0];
843 eptr = ptr + nb_coefs[ch];
844 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
846 code = get_vlc(&pwd->gb, coef_vlc->table,
850 if (code == 1) /* EOB */
852 if (code == 0) { /* escape */
853 level = get_bits(&pwd->gb, coef_nb_bits);
854 /* reading block_len_bits would be better */
855 run = get_bits(&pwd->gb, pwd->frame_len_bits);
856 } else { /* normal code */
857 run = run_table[code];
858 level = level_table[code];
860 if (!get_bit(&pwd->gb))
864 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
868 if (ptr >= eptr) /* EOB can be omitted */
875 int n4 = pwd->block_len / 2;
876 mdct_norm = 1.0 / (float) n4;
879 /* finally compute the MDCT coefficients */
880 for (ch = 0; ch < pwd->ahi.channels; ch++) {
881 if (pwd->channel_coded[ch]) {
883 float *coefs, *exponents, mult, mult1, noise;
884 int i, j, n1, last_high_band, esize;
885 float exp_power[HIGH_BAND_MAX_SIZE];
887 coefs1 = pwd->coefs1[ch];
888 exponents = pwd->exponents[ch];
889 esize = pwd->exponents_bsize[ch];
890 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
892 coefs = pwd->coefs[ch];
893 if (pwd->use_noise_coding) {
895 /* very low freqs : noise */
896 for (i = 0; i < pwd->coefs_start; i++) {
898 pwd->noise_table[pwd->noise_index] *
899 exponents[i << bsize >> esize] *
903 1) & (NOISE_TAB_SIZE - 1);
906 n1 = pwd->exponent_high_sizes[bsize];
908 /* compute power of high bands */
909 exponents = pwd->exponents[ch] +
910 (pwd->high_band_start[bsize] << bsize);
911 last_high_band = 0; /* avoid warning */
912 for (j = 0; j < n1; j++) {
913 n = pwd->exponent_high_bands[pwd->
919 if (pwd->high_band_coded[ch][j]) {
922 for (i = 0; i < n; i++) {
923 val = exponents[i << bsize
927 exp_power[j] = e2 / n;
930 exponents += n << bsize;
933 /* main freqs and high freqs */
936 (pwd->coefs_start << bsize);
937 for (j = -1; j < n1; j++) {
939 n = pwd->high_band_start[bsize] -
942 n = pwd->exponent_high_bands[pwd->
949 if (j >= 0 && pwd->high_band_coded[ch][j]) {
950 /* use noise with specified power */
955 /* XXX: use a table */
963 (pwd->max_exponent[ch] *
966 for (i = 0; i < n; i++) {
968 pwd->noise_table[pwd->
981 exponents += n << bsize;
983 /* coded values + small noise */
984 for (i = 0; i < n; i++) {
986 pwd->noise_table[pwd->
1000 exponents += n << bsize;
1004 /* very high freqs : noise */
1005 n = pwd->block_len - pwd->coefs_end[bsize];
1007 mult * exponents[((-1 << bsize)) >> esize];
1008 for (i = 0; i < n; i++) {
1010 pwd->noise_table[pwd->noise_index] *
1014 1) & (NOISE_TAB_SIZE - 1);
1017 /* XXX: optimize more */
1018 for (i = 0; i < pwd->coefs_start; i++)
1021 for (i = 0; i < n; i++) {
1024 exponents[i << bsize >> esize] *
1027 n = pwd->block_len - pwd->coefs_end[bsize];
1028 for (i = 0; i < n; i++)
1034 if (pwd->ms_stereo && pwd->channel_coded[1]) {
1039 * Nominal case for ms stereo: we do it before mdct.
1041 * No need to optimize this case because it should almost never
1044 if (!pwd->channel_coded[0]) {
1045 PARA_NOTICE_LOG("rare ms-stereo\n");
1046 memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
1047 pwd->channel_coded[0] = 1;
1049 for (i = 0; i < pwd->block_len; i++) {
1050 a = pwd->coefs[0][i];
1051 b = pwd->coefs[1][i];
1052 pwd->coefs[0][i] = a + b;
1053 pwd->coefs[1][i] = a - b;
1058 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1062 n4 = pwd->block_len / 2;
1063 if (pwd->channel_coded[ch])
1064 imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
1065 else if (!(pwd->ms_stereo && ch == 1))
1066 memset(pwd->output, 0, sizeof(pwd->output));
1068 /* multiply by the window and add in the frame */
1069 index = (pwd->frame_len / 2) + pwd->block_pos - n4;
1070 wma_window(pwd, &pwd->frame_out[ch][index]);
1073 /* update block number */
1074 pwd->block_pos += pwd->block_len;
1075 if (pwd->block_pos >= pwd->frame_len)
1082 * Clip a signed integer value into the -32768,32767 range.
1084 * \param a The value to clip.
1086 * \return The clipped value.
1088 static inline int16_t av_clip_int16(int a)
1090 if ((a + 32768) & ~65535)
1091 return (a >> 31) ^ 32767;
1096 /* Decode a frame of frame_len samples. */
1097 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1099 int ret, i, n, ch, incr;
1103 /* read each block */
1106 ret = wma_decode_block(pwd);
1113 /* convert frame to integer */
1115 incr = pwd->ahi.channels;
1116 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1118 iptr = pwd->frame_out[ch];
1120 for (i = 0; i < n; i++) {
1121 *ptr = av_clip_int16(lrintf(*iptr++));
1124 /* prepare for next block */
1125 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1126 pwd->frame_len * sizeof(float));
1131 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
1132 int *data_size, const uint8_t *buf, int buf_size)
1136 static int frame_count;
1138 if (buf_size == 0) {
1139 pwd->last_superframe_len = 0;
1142 if (buf_size < pwd->ahi.block_align)
1144 buf_size = pwd->ahi.block_align;
1146 init_get_bits(&pwd->gb, buf, buf_size);
1147 if (pwd->use_bit_reservoir) {
1148 int i, nb_frames, bit_offset, pos, len;
1151 /* read super frame header */
1152 skip_bits(&pwd->gb, 4); /* super frame index */
1153 nb_frames = get_bits(&pwd->gb, 4) - 1;
1154 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1155 ret = -E_WMA_OUTPUT_SPACE;
1156 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1157 * sizeof(int16_t) > *data_size)
1160 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1162 if (pwd->last_superframe_len > 0) {
1163 /* add bit_offset bits to last frame */
1164 ret = -E_WMA_BAD_SUPERFRAME;
1165 if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1166 MAX_CODED_SUPERFRAME_SIZE)
1168 q = pwd->last_superframe + pwd->last_superframe_len;
1171 *q++ = get_bits(&pwd->gb, 8);
1175 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1177 /* XXX: bit_offset bits into last frame */
1178 init_get_bits(&pwd->gb, pwd->last_superframe,
1179 MAX_CODED_SUPERFRAME_SIZE);
1180 /* skip unused bits */
1181 if (pwd->last_bitoffset > 0)
1182 skip_bits(&pwd->gb, pwd->last_bitoffset);
1184 * This frame is stored in the last superframe and in
1187 ret = -E_WMA_DECODE;
1188 if (wma_decode_frame(pwd, samples) < 0)
1191 samples += pwd->ahi.channels * pwd->frame_len;
1194 /* read each frame starting from bit_offset */
1195 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1196 init_get_bits(&pwd->gb, buf + (pos >> 3),
1197 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1200 skip_bits(&pwd->gb, len);
1202 pwd->reset_block_lengths = 1;
1203 for (i = 0; i < nb_frames; i++) {
1204 ret = -E_WMA_DECODE;
1205 if (wma_decode_frame(pwd, samples) < 0)
1208 samples += pwd->ahi.channels * pwd->frame_len;
1211 /* we copy the end of the frame in the last frame buffer */
1212 pos = get_bits_count(&pwd->gb) +
1213 ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1214 pwd->last_bitoffset = pos & 7;
1216 len = buf_size - pos;
1217 ret = -E_WMA_BAD_SUPERFRAME;
1218 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1220 pwd->last_superframe_len = len;
1221 memcpy(pwd->last_superframe, buf + pos, len);
1223 PARA_DEBUG_LOG("not using bit reservoir\n");
1224 ret = -E_WMA_OUTPUT_SPACE;
1225 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *data_size)
1227 /* single frame decode */
1228 ret = -E_WMA_DECODE;
1229 if (wma_decode_frame(pwd, samples) < 0)
1232 samples += pwd->ahi.channels * pwd->frame_len;
1234 PARA_DEBUG_LOG("frame_count: %d frame_len: %d, block_len: %d, "
1235 "outbytes: %d, eaten: %d\n",
1236 frame_count, pwd->frame_len, pwd->block_len,
1237 (int8_t *) samples - (int8_t *) data, pwd->ahi.block_align);
1238 *data_size = (int8_t *)samples - (int8_t *)data;
1239 return pwd->ahi.block_align;
1241 /* reset the bit reservoir on errors */
1242 pwd->last_superframe_len = 0;
1246 static ssize_t wmadec_convert(char *inbuffer, size_t len,
1247 struct filter_node *fn)
1249 int ret, out_size = fn->bufsize - fn->loaded;
1250 struct private_wmadec_data *pwd = fn->private_data;
1252 if (out_size < 128 * 1024)
1255 ret = wma_decode_init(inbuffer, len, &pwd);
1258 fn->private_data = pwd;
1259 fn->fc->channels = pwd->ahi.channels;
1260 fn->fc->samplerate = pwd->ahi.sample_rate;
1261 return pwd->ahi.header_len;
1264 if (len <= WMA_FRAME_SKIP + pwd->ahi.block_align)
1266 ret = wma_decode_superframe(pwd, fn->buf + fn->loaded,
1267 &out_size, (uint8_t *)inbuffer + WMA_FRAME_SKIP,
1268 len - WMA_FRAME_SKIP);
1271 fn->loaded += out_size;
1272 return ret + WMA_FRAME_SKIP;
1275 static void wmadec_close(struct filter_node *fn)
1277 struct private_wmadec_data *pwd = fn->private_data;
1281 wmadec_cleanup(pwd);
1284 free(fn->private_data);
1285 fn->private_data = NULL;
1288 static void wmadec_open(struct filter_node *fn)
1290 fn->bufsize = 1024 * 1024;
1291 fn->buf = para_malloc(fn->bufsize);
1292 fn->private_data = NULL;
1297 * The init function of the wma decoder.
1299 * \param f Its fields are filled in by the function.
1301 void wmadec_filter_init(struct filter *f)
1303 f->open = wmadec_open;
1304 f->close = wmadec_close;
1305 f->convert = wmadec_convert;