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
27 #include <sys/select.h>
35 #include "buffer_tree.h"
37 #include "bitstream.h"
44 #define BLOCK_MIN_BITS 7
45 #define BLOCK_MAX_BITS 11
46 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
48 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
50 /* XXX: find exact max size */
51 #define HIGH_BAND_MAX_SIZE 16
53 /* XXX: is it a suitable value ? */
54 #define MAX_CODED_SUPERFRAME_SIZE 16384
56 #define MAX_CHANNELS 2
58 #define NOISE_TAB_SIZE 8192
60 #define LSP_POW_BITS 7
62 struct private_wmadec_data {
63 /** Information contained in the audio file header. */
64 struct asf_header_info ahi;
65 struct getbit_context gb;
66 /** Whether to use the bit reservoir. */
67 int use_bit_reservoir;
68 /** Whether to use variable block length. */
69 int use_variable_block_len;
70 /** Whether to use exponent coding. */
72 /** Whether perceptual noise is added. */
74 /** Depends on number of the bits per second and the frame length. */
76 /** Only used if use_exp_vlc is true. */
78 int exponent_sizes[BLOCK_NB_SIZES];
79 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
80 /** The index of the first coef in high band. */
81 int high_band_start[BLOCK_NB_SIZES];
82 /** Maximal number of coded coefficients. */
83 int coefs_end[BLOCK_NB_SIZES];
84 int exponent_high_sizes[BLOCK_NB_SIZES];
85 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
88 /* coded values in high bands */
89 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
90 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
92 /* there are two possible tables for spectral coefficients */
93 struct vlc coef_vlc[2];
94 uint16_t *run_table[2];
95 uint16_t *level_table[2];
96 const struct coef_vlc_table *coef_vlcs[2];
97 /** Frame length in samples. */
99 /** log2 of frame_len. */
101 /** Number of block sizes. */
104 int reset_block_lengths;
105 /** log2 of current block length. */
107 /** log2 of next block length. */
108 int next_block_len_bits;
109 /** log2 of previous block length. */
110 int prev_block_len_bits;
111 /** Block length in samples. */
113 /** Current position in frame. */
115 /** True if mid/side stereo mode. */
117 /** True if channel is coded. */
118 uint8_t channel_coded[MAX_CHANNELS];
119 /** log2 ratio frame/exp. length. */
120 int exponents_bsize[MAX_CHANNELS];
122 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
123 float max_exponent[MAX_CHANNELS];
124 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
125 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
126 float output[BLOCK_MAX_SIZE * 2];
127 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
128 float *windows[BLOCK_NB_SIZES];
129 /** Output buffer for one frame and the last for IMDCT windowing. */
130 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
131 /** Last frame info. */
132 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
134 int last_superframe_len;
135 float noise_table[NOISE_TAB_SIZE];
137 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
138 /* lsp_to_curve tables */
139 float lsp_cos_table[BLOCK_MAX_SIZE];
140 float lsp_pow_e_table[256];
141 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
142 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
146 #define EXPMAX DIV_ROUND_UP(19, EXPVLCBITS)
148 #define HGAINVLCBITS 9
149 #define HGAINMAX DIV_ROUND_UP(13, HGAINVLCBITS)
152 #define VLCMAX DIV_ROUND_UP(22, VLCBITS)
154 #define SINE_WINDOW(x) static float sine_ ## x[x] __a_aligned(16)
163 static float *sine_windows[6] = {
164 sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
167 /* Generate a sine window. */
168 static void sine_window_init(float *window, int n)
172 for (i = 0; i < n; i++)
173 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
176 static void wmadec_cleanup(struct private_wmadec_data *pwd)
180 for (i = 0; i < pwd->nb_block_sizes; i++)
181 imdct_end(pwd->mdct_ctx[i]);
182 if (pwd->use_exp_vlc)
183 free_vlc(&pwd->exp_vlc);
184 if (pwd->use_noise_coding)
185 free_vlc(&pwd->hgain_vlc);
186 for (i = 0; i < 2; i++) {
187 free_vlc(&pwd->coef_vlc[i]);
188 free(pwd->run_table[i]);
189 free(pwd->level_table[i]);
193 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
194 uint16_t **plevel_table, const struct coef_vlc_table *vlc_table)
196 int n = vlc_table->n;
197 const uint8_t *table_bits = vlc_table->huffbits;
198 const uint32_t *table_codes = vlc_table->huffcodes;
199 const uint16_t *levels_table = vlc_table->levels;
200 uint16_t *run_table, *level_table;
201 int i, l, j, k, level;
203 init_vlc(vlc, VLCBITS, n, table_bits, table_codes, 4);
205 run_table = para_malloc(n * sizeof(uint16_t));
206 level_table = para_malloc(n * sizeof(uint16_t));
211 l = levels_table[k++];
212 for (j = 0; j < l; j++) {
214 level_table[i] = level;
219 *prun_table = run_table;
220 *plevel_table = level_table;
223 /* compute the scale factor band sizes for each MDCT block size */
224 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
227 struct asf_header_info *ahi = &pwd->ahi;
228 int a, b, pos, lpos, k, block_len, i, j, n;
229 const uint8_t *table;
231 for (k = 0; k < pwd->nb_block_sizes; k++) {
232 block_len = pwd->frame_len >> k;
235 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
237 if (ahi->sample_rate >= 44100)
238 table = exponent_band_44100[a];
239 else if (ahi->sample_rate >= 32000)
240 table = exponent_band_32000[a];
241 else if (ahi->sample_rate >= 22050)
242 table = exponent_band_22050[a];
246 for (i = 0; i < n; i++)
247 pwd->exponent_bands[k][i] = table[i];
248 pwd->exponent_sizes[k] = n;
252 for (i = 0; i < 25; i++) {
253 a = wma_critical_freqs[i];
254 b = ahi->sample_rate;
255 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
260 pwd->exponent_bands[k][j++] = pos - lpos;
261 if (pos >= block_len)
265 pwd->exponent_sizes[k] = j;
268 /* max number of coefs */
269 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
270 /* high freq computation */
271 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
272 / ahi->sample_rate + 0.5);
273 n = pwd->exponent_sizes[k];
276 for (i = 0; i < n; i++) {
279 pos += pwd->exponent_bands[k][i];
281 if (start < pwd->high_band_start[k])
282 start = pwd->high_band_start[k];
283 if (end > pwd->coefs_end[k])
284 end = pwd->coefs_end[k];
286 pwd->exponent_high_bands[k][j++] = end - start;
288 pwd->exponent_high_sizes[k] = j;
292 static int wma_init(struct private_wmadec_data *pwd)
295 float bps1, high_freq;
299 struct asf_header_info *ahi = &pwd->ahi;
300 int flags2 = ahi->flags2;
302 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
303 || ahi->channels <= 0 || ahi->channels > 8
304 || ahi->bit_rate <= 0)
305 return -E_WMA_BAD_PARAMS;
307 /* compute MDCT block size */
308 if (ahi->sample_rate <= 16000)
309 pwd->frame_len_bits = 9;
310 else if (ahi->sample_rate <= 22050)
311 pwd->frame_len_bits = 10;
313 pwd->frame_len_bits = 11;
314 pwd->frame_len = 1 << pwd->frame_len_bits;
315 if (pwd->use_variable_block_len) {
317 nb = ((flags2 >> 3) & 3) + 1;
318 if ((ahi->bit_rate / ahi->channels) >= 32000)
320 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
323 pwd->nb_block_sizes = nb + 1;
325 pwd->nb_block_sizes = 1;
327 /* init rate dependent parameters */
328 pwd->use_noise_coding = 1;
329 high_freq = ahi->sample_rate * 0.5;
331 /* wma2 rates are normalized */
332 sample_rate1 = ahi->sample_rate;
333 if (sample_rate1 >= 44100)
334 sample_rate1 = 44100;
335 else if (sample_rate1 >= 22050)
336 sample_rate1 = 22050;
337 else if (sample_rate1 >= 16000)
338 sample_rate1 = 16000;
339 else if (sample_rate1 >= 11025)
340 sample_rate1 = 11025;
341 else if (sample_rate1 >= 8000)
344 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
345 pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
347 * Compute high frequency value and choose if noise coding should be
351 if (ahi->channels == 2)
353 if (sample_rate1 == 44100) {
355 pwd->use_noise_coding = 0;
357 high_freq = high_freq * 0.4;
358 } else if (sample_rate1 == 22050) {
360 pwd->use_noise_coding = 0;
361 else if (bps1 >= 0.72)
362 high_freq = high_freq * 0.7;
364 high_freq = high_freq * 0.6;
365 } else if (sample_rate1 == 16000) {
367 high_freq = high_freq * 0.5;
369 high_freq = high_freq * 0.3;
370 } else if (sample_rate1 == 11025)
371 high_freq = high_freq * 0.7;
372 else if (sample_rate1 == 8000) {
374 high_freq = high_freq * 0.5;
376 pwd->use_noise_coding = 0;
378 high_freq = high_freq * 0.65;
381 high_freq = high_freq * 0.75;
383 high_freq = high_freq * 0.6;
385 high_freq = high_freq * 0.5;
387 PARA_INFO_LOG("channels=%d sample_rate=%d "
388 "bitrate=%d block_align=%d\n",
389 ahi->channels, ahi->sample_rate,
390 ahi->bit_rate, ahi->block_align);
391 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
392 "high_freq=%f bitoffset=%d\n",
393 pwd->frame_len, bps, bps1,
394 high_freq, pwd->byte_offset_bits);
395 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
396 pwd->use_noise_coding, pwd->use_exp_vlc, pwd->nb_block_sizes);
398 compute_scale_factor_band_sizes(pwd, high_freq);
399 /* init MDCT windows : simple sinus window */
400 for (i = 0; i < pwd->nb_block_sizes; i++) {
402 n = 1 << (pwd->frame_len_bits - i);
403 sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
404 pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
407 pwd->reset_block_lengths = 1;
409 if (pwd->use_noise_coding) {
410 /* init the noise generator */
411 if (pwd->use_exp_vlc)
412 pwd->noise_mult = 0.02;
414 pwd->noise_mult = 0.04;
420 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
421 for (i = 0; i < NOISE_TAB_SIZE; i++) {
422 seed = seed * 314159 + 1;
423 pwd->noise_table[i] = (float) ((int) seed) * norm;
428 /* choose the VLC tables for the coefficients */
430 if (ahi->sample_rate >= 32000) {
433 else if (bps1 < 1.16)
436 pwd->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
437 pwd->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
438 init_coef_vlc(&pwd->coef_vlc[0], &pwd->run_table[0], &pwd->level_table[0],
440 init_coef_vlc(&pwd->coef_vlc[1], &pwd->run_table[1], &pwd->level_table[1],
445 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd, int frame_len)
450 wdel = M_PI / frame_len;
451 for (i = 0; i < frame_len; i++)
452 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
454 /* tables for x^-0.25 computation */
455 for (i = 0; i < 256; i++) {
457 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
460 /* These two tables are needed to avoid two operations in pow_m1_4. */
462 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
463 m = (1 << LSP_POW_BITS) + i;
464 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
466 pwd->lsp_pow_m_table1[i] = 2 * a - b;
467 pwd->lsp_pow_m_table2[i] = b - a;
472 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
474 struct private_wmadec_data *pwd;
477 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
478 pwd = para_calloc(sizeof(*pwd));
479 ret = read_asf_header(initial_buf, len, &pwd->ahi);
485 pwd->use_exp_vlc = pwd->ahi.flags2 & 0x0001;
486 pwd->use_bit_reservoir = pwd->ahi.flags2 & 0x0002;
487 pwd->use_variable_block_len = pwd->ahi.flags2 & 0x0004;
493 for (i = 0; i < pwd->nb_block_sizes; i++) {
494 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
498 if (pwd->use_noise_coding) {
499 PARA_INFO_LOG("using noise coding\n");
500 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
501 sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
502 wma_hgain_huffcodes, 2);
505 if (pwd->use_exp_vlc) {
506 PARA_INFO_LOG("using exp_vlc\n");
507 init_vlc(&pwd->exp_vlc, EXPVLCBITS,
508 sizeof(wma_scale_huffbits), wma_scale_huffbits,
509 wma_scale_huffcodes, 4);
511 PARA_INFO_LOG("using curve\n");
512 wma_lsp_to_curve_init(pwd, pwd->frame_len);
515 return pwd->ahi.header_len;
519 * compute x^-0.25 with an exponent and mantissa table. We use linear
520 * interpolation to reduce the mantissa table size at a small speed
521 * expense (linear interpolation approximately doubles the number of
522 * bits of precision).
524 static inline float pow_m1_4(struct private_wmadec_data *pwd, float x)
535 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
536 /* build interpolation scale: 1 <= t < 2. */
537 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
538 a = pwd->lsp_pow_m_table1[m];
539 b = pwd->lsp_pow_m_table2[m];
540 return pwd->lsp_pow_e_table[e] * (a + b * t.f);
543 static void wma_lsp_to_curve(struct private_wmadec_data *pwd,
544 float *out, float *val_max_ptr, int n, float *lsp)
547 float p, q, w, v, val_max;
550 for (i = 0; i < n; i++) {
553 w = pwd->lsp_cos_table[i];
554 for (j = 1; j < NB_LSP_COEFS; j += 2) {
561 v = pow_m1_4(pwd, v);
566 *val_max_ptr = val_max;
569 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
570 static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
572 float lsp_coefs[NB_LSP_COEFS];
575 for (i = 0; i < NB_LSP_COEFS; i++) {
576 if (i == 0 || i >= 8)
577 val = get_bits(&pwd->gb, 3);
579 val = get_bits(&pwd->gb, 4);
580 lsp_coefs[i] = wma_lsp_codebook[i][val];
583 wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
584 pwd->block_len, lsp_coefs);
587 /* Decode exponents coded with VLC codes. */
588 static int decode_exp_vlc(struct private_wmadec_data *pwd, int ch)
590 int last_exp, n, code;
591 const uint16_t *ptr, *band_ptr;
592 float v, *q, max_scale, *q_end;
594 band_ptr = pwd->exponent_bands[pwd->frame_len_bits - pwd->block_len_bits];
596 q = pwd->exponents[ch];
597 q_end = q + pwd->block_len;
602 code = get_vlc(&pwd->gb, pwd->exp_vlc.table, EXPVLCBITS, EXPMAX);
605 /* NOTE: this offset is the same as MPEG4 AAC ! */
606 last_exp += code - 60;
607 /* XXX: use a table */
608 v = pow(10, last_exp * (1.0 / 16.0));
616 pwd->max_exponent[ch] = max_scale;
620 /* compute src0 * src1 + src2 */
621 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
622 const float *src2, int len)
626 for (i = 0; i < len; i++)
627 dst[i] = src0[i] * src1[i] + src2[i];
630 static inline void vector_mult_reverse(float *dst, const float *src0,
631 const float *src1, int len)
636 for (i = 0; i < len; i++)
637 dst[i] = src0[i] * src1[-i];
641 * Apply MDCT window and add into output.
643 * We ensure that when the windows overlap their squared sum
644 * is always 1 (MDCT reconstruction rule).
646 static void wma_window(struct private_wmadec_data *pwd, float *out)
648 float *in = pwd->output;
649 int block_len, bsize, n;
652 if (pwd->block_len_bits <= pwd->prev_block_len_bits) {
653 block_len = pwd->block_len;
654 bsize = pwd->frame_len_bits - pwd->block_len_bits;
655 vector_mult_add(out, in, pwd->windows[bsize], out, block_len);
657 block_len = 1 << pwd->prev_block_len_bits;
658 n = (pwd->block_len - block_len) / 2;
659 bsize = pwd->frame_len_bits - pwd->prev_block_len_bits;
660 vector_mult_add(out + n, in + n, pwd->windows[bsize], out + n,
662 memcpy(out + n + block_len, in + n + block_len,
665 out += pwd->block_len;
666 in += pwd->block_len;
668 if (pwd->block_len_bits <= pwd->next_block_len_bits) {
669 block_len = pwd->block_len;
670 bsize = pwd->frame_len_bits - pwd->block_len_bits;
671 vector_mult_reverse(out, in, pwd->windows[bsize], block_len);
673 block_len = 1 << pwd->next_block_len_bits;
674 n = (pwd->block_len - block_len) / 2;
675 bsize = pwd->frame_len_bits - pwd->next_block_len_bits;
676 memcpy(out, in, n * sizeof(float));
677 vector_mult_reverse(out + n, in + n, pwd->windows[bsize],
679 memset(out + n + block_len, 0, n * sizeof(float));
683 static int wma_total_gain_to_bits(int total_gain)
687 else if (total_gain < 32)
689 else if (total_gain < 40)
691 else if (total_gain < 45)
697 static int compute_high_band_values(struct private_wmadec_data *pwd,
698 int bsize, int nb_coefs[MAX_CHANNELS])
702 if (!pwd->use_noise_coding)
704 for (ch = 0; ch < pwd->ahi.channels; ch++) {
706 if (!pwd->channel_coded[ch])
708 m = pwd->exponent_high_sizes[bsize];
709 for (i = 0; i < m; i++) {
710 a = get_bit(&pwd->gb);
711 pwd->high_band_coded[ch][i] = a;
714 nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
717 for (ch = 0; ch < pwd->ahi.channels; ch++) {
719 if (!pwd->channel_coded[ch])
721 n = pwd->exponent_high_sizes[bsize];
722 val = (int)0x80000000;
723 for (i = 0; i < n; i++) {
724 if (!pwd->high_band_coded[ch][i])
726 if (val == (int)0x80000000)
727 val = get_bits(&pwd->gb, 7) - 19;
729 int code = get_vlc(&pwd->gb,
730 pwd->hgain_vlc.table, HGAINVLCBITS,
736 pwd->high_band_values[ch][i] = val;
742 static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
743 int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
746 float mdct_norm = 1.0 / (pwd->block_len / 2);
748 for (ch = 0; ch < pwd->ahi.channels; ch++) {
750 float *coefs, *exponents, mult, mult1, noise;
751 int i, j, n, n1, last_high_band, esize;
752 float exp_power[HIGH_BAND_MAX_SIZE];
754 if (!pwd->channel_coded[ch])
756 coefs1 = pwd->coefs1[ch];
757 exponents = pwd->exponents[ch];
758 esize = pwd->exponents_bsize[ch];
759 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
761 coefs = pwd->coefs[ch];
762 if (!pwd->use_noise_coding) {
763 /* XXX: optimize more */
765 for (i = 0; i < n; i++)
766 *coefs++ = coefs1[i] *
767 exponents[i << bsize >> esize] * mult;
768 n = pwd->block_len - pwd->coefs_end[bsize];
769 for (i = 0; i < n; i++)
773 n1 = pwd->exponent_high_sizes[bsize];
774 /* compute power of high bands */
775 exponents = pwd->exponents[ch] +
776 (pwd->high_band_start[bsize] << bsize);
777 last_high_band = 0; /* avoid warning */
778 for (j = 0; j < n1; j++) {
779 n = pwd->exponent_high_bands[
780 pwd->frame_len_bits - pwd->block_len_bits][j];
781 if (pwd->high_band_coded[ch][j]) {
784 for (i = 0; i < n; i++) {
785 val = exponents[i << bsize >> esize];
788 exp_power[j] = e2 / n;
791 exponents += n << bsize;
793 /* main freqs and high freqs */
794 exponents = pwd->exponents[ch];
795 for (j = -1; j < n1; j++) {
797 n = pwd->high_band_start[bsize];
799 n = pwd->exponent_high_bands[pwd->frame_len_bits
800 - pwd->block_len_bits][j];
801 if (j >= 0 && pwd->high_band_coded[ch][j]) {
802 /* use noise with specified power */
803 mult1 = sqrt(exp_power[j]
804 / exp_power[last_high_band]);
805 /* XXX: use a table */
806 mult1 *= pow(10, pwd->high_band_values[ch][j] * 0.05);
807 mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
809 for (i = 0; i < n; i++) {
810 noise = pwd->noise_table[pwd->noise_index];
811 pwd->noise_index = (pwd->noise_index + 1)
812 & (NOISE_TAB_SIZE - 1);
813 *coefs++ = noise * exponents[
814 i << bsize >> esize] * mult1;
816 exponents += n << bsize;
818 /* coded values + small noise */
819 for (i = 0; i < n; i++) {
820 noise = pwd->noise_table[pwd->noise_index];
821 pwd->noise_index = (pwd->noise_index + 1)
822 & (NOISE_TAB_SIZE - 1);
823 *coefs++ = ((*coefs1++) + noise) *
824 exponents[i << bsize >> esize]
827 exponents += n << bsize;
830 /* very high freqs: noise */
831 n = pwd->block_len - pwd->coefs_end[bsize];
832 mult1 = mult * exponents[((-1 << bsize)) >> esize];
833 for (i = 0; i < n; i++) {
834 *coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
835 pwd->noise_index = (pwd->noise_index + 1)
836 & (NOISE_TAB_SIZE - 1);
842 * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
845 static int wma_decode_block(struct private_wmadec_data *pwd)
847 int ret, n, v, ch, code, bsize;
848 int coef_nb_bits, total_gain;
849 int nb_coefs[MAX_CHANNELS];
851 /* compute current block length */
852 if (pwd->use_variable_block_len) {
853 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
855 if (pwd->reset_block_lengths) {
856 pwd->reset_block_lengths = 0;
857 v = get_bits(&pwd->gb, n);
858 if (v >= pwd->nb_block_sizes)
859 return -E_WMA_BLOCK_SIZE;
860 pwd->prev_block_len_bits = pwd->frame_len_bits - v;
861 v = get_bits(&pwd->gb, n);
862 if (v >= pwd->nb_block_sizes)
863 return -E_WMA_BLOCK_SIZE;
864 pwd->block_len_bits = pwd->frame_len_bits - v;
866 /* update block lengths */
867 pwd->prev_block_len_bits = pwd->block_len_bits;
868 pwd->block_len_bits = pwd->next_block_len_bits;
870 v = get_bits(&pwd->gb, n);
871 if (v >= pwd->nb_block_sizes)
872 return -E_WMA_BLOCK_SIZE;
873 pwd->next_block_len_bits = pwd->frame_len_bits - v;
875 /* fixed block len */
876 pwd->next_block_len_bits = pwd->frame_len_bits;
877 pwd->prev_block_len_bits = pwd->frame_len_bits;
878 pwd->block_len_bits = pwd->frame_len_bits;
881 /* now check if the block length is coherent with the frame length */
882 pwd->block_len = 1 << pwd->block_len_bits;
883 if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
884 return -E_INCOHERENT_BLOCK_LEN;
886 if (pwd->ahi.channels == 2)
887 pwd->ms_stereo = get_bit(&pwd->gb);
889 for (ch = 0; ch < pwd->ahi.channels; ch++) {
890 int a = get_bit(&pwd->gb);
891 pwd->channel_coded[ch] = a;
895 bsize = pwd->frame_len_bits - pwd->block_len_bits;
897 /* if no channel coded, no need to go further */
898 /* XXX: fix potential framing problems */
903 * Read total gain and extract corresponding number of bits for coef
908 int a = get_bits(&pwd->gb, 7);
914 coef_nb_bits = wma_total_gain_to_bits(total_gain);
916 /* compute number of coefficients */
917 n = pwd->coefs_end[bsize];
918 for (ch = 0; ch < pwd->ahi.channels; ch++)
921 ret = compute_high_band_values(pwd, bsize, nb_coefs);
925 /* exponents can be reused in short blocks. */
926 if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
927 for (ch = 0; ch < pwd->ahi.channels; ch++) {
928 if (pwd->channel_coded[ch]) {
929 if (pwd->use_exp_vlc) {
930 ret = decode_exp_vlc(pwd, ch);
934 decode_exp_lsp(pwd, ch);
935 pwd->exponents_bsize[ch] = bsize;
940 /* parse spectral coefficients : just RLE encoding */
941 for (ch = 0; ch < pwd->ahi.channels; ch++) {
942 struct vlc *coef_vlc;
943 int level, run, tindex;
945 const uint16_t *level_table, *run_table;
947 if (!pwd->channel_coded[ch])
950 * special VLC tables are used for ms stereo because there is
951 * potentially less energy there
953 tindex = (ch == 1 && pwd->ms_stereo);
954 coef_vlc = &pwd->coef_vlc[tindex];
955 run_table = pwd->run_table[tindex];
956 level_table = pwd->level_table[tindex];
958 ptr = &pwd->coefs1[ch][0];
959 eptr = ptr + nb_coefs[ch];
960 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
962 code = get_vlc(&pwd->gb, coef_vlc->table,
966 if (code == 1) /* EOB */
968 if (code == 0) { /* escape */
969 level = get_bits(&pwd->gb, coef_nb_bits);
970 /* reading block_len_bits would be better */
971 run = get_bits(&pwd->gb, pwd->frame_len_bits);
972 } else { /* normal code */
973 run = run_table[code];
974 level = level_table[code];
976 if (!get_bit(&pwd->gb))
980 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
984 if (ptr >= eptr) /* EOB can be omitted */
988 compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
989 if (pwd->ms_stereo && pwd->channel_coded[1]) {
993 * Nominal case for ms stereo: we do it before mdct.
995 * No need to optimize this case because it should almost never
998 if (!pwd->channel_coded[0]) {
999 PARA_NOTICE_LOG("rare ms-stereo\n");
1000 memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
1001 pwd->channel_coded[0] = 1;
1003 for (i = 0; i < pwd->block_len; i++) {
1004 a = pwd->coefs[0][i];
1005 b = pwd->coefs[1][i];
1006 pwd->coefs[0][i] = a + b;
1007 pwd->coefs[1][i] = a - b;
1011 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1014 n4 = pwd->block_len / 2;
1015 if (pwd->channel_coded[ch])
1016 imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
1017 else if (!(pwd->ms_stereo && ch == 1))
1018 memset(pwd->output, 0, sizeof(pwd->output));
1020 /* multiply by the window and add in the frame */
1021 idx = (pwd->frame_len / 2) + pwd->block_pos - n4;
1022 wma_window(pwd, &pwd->frame_out[ch][idx]);
1025 /* update block number */
1026 pwd->block_pos += pwd->block_len;
1027 if (pwd->block_pos >= pwd->frame_len)
1034 * Clip a signed integer value into the -32768,32767 range.
1036 * \param a The value to clip.
1038 * \return The clipped value.
1040 static inline int16_t av_clip_int16(int a)
1042 if ((a + 32768) & ~65535)
1043 return (a >> 31) ^ 32767;
1048 /* Decode a frame of frame_len samples. */
1049 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1051 int ret, i, n, ch, incr;
1055 /* read each block */
1058 ret = wma_decode_block(pwd);
1065 /* convert frame to integer */
1067 incr = pwd->ahi.channels;
1068 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1070 iptr = pwd->frame_out[ch];
1072 for (i = 0; i < n; i++) {
1073 *ptr = av_clip_int16(lrintf(*iptr++));
1076 /* prepare for next block */
1077 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1078 pwd->frame_len * sizeof(float));
1083 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
1084 int *data_size, const uint8_t *buf, int buf_size)
1089 if (buf_size == 0) {
1090 pwd->last_superframe_len = 0;
1093 if (buf_size < pwd->ahi.block_align)
1095 buf_size = pwd->ahi.block_align;
1097 init_get_bits(&pwd->gb, buf, buf_size);
1098 if (pwd->use_bit_reservoir) {
1099 int i, nb_frames, bit_offset, pos, len;
1102 /* read super frame header */
1103 skip_bits(&pwd->gb, 4); /* super frame index */
1104 nb_frames = get_bits(&pwd->gb, 4) - 1;
1105 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1106 ret = -E_WMA_OUTPUT_SPACE;
1107 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1108 * sizeof(int16_t) > *data_size)
1111 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1113 if (pwd->last_superframe_len > 0) {
1114 /* add bit_offset bits to last frame */
1115 ret = -E_WMA_BAD_SUPERFRAME;
1116 if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1117 MAX_CODED_SUPERFRAME_SIZE)
1119 q = pwd->last_superframe + pwd->last_superframe_len;
1122 *q++ = get_bits(&pwd->gb, 8);
1126 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1128 /* XXX: bit_offset bits into last frame */
1129 init_get_bits(&pwd->gb, pwd->last_superframe,
1130 MAX_CODED_SUPERFRAME_SIZE);
1131 /* skip unused bits */
1132 if (pwd->last_bitoffset > 0)
1133 skip_bits(&pwd->gb, pwd->last_bitoffset);
1135 * This frame is stored in the last superframe and in
1138 ret = wma_decode_frame(pwd, samples);
1141 samples += pwd->ahi.channels * pwd->frame_len;
1144 /* read each frame starting from bit_offset */
1145 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1146 init_get_bits(&pwd->gb, buf + (pos >> 3),
1147 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1150 skip_bits(&pwd->gb, len);
1152 pwd->reset_block_lengths = 1;
1153 for (i = 0; i < nb_frames; i++) {
1154 ret = wma_decode_frame(pwd, samples);
1157 samples += pwd->ahi.channels * pwd->frame_len;
1160 /* we copy the end of the frame in the last frame buffer */
1161 pos = get_bits_count(&pwd->gb) +
1162 ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1163 pwd->last_bitoffset = pos & 7;
1165 len = buf_size - pos;
1166 ret = -E_WMA_BAD_SUPERFRAME;
1167 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1169 pwd->last_superframe_len = len;
1170 memcpy(pwd->last_superframe, buf + pos, len);
1172 PARA_DEBUG_LOG("not using bit reservoir\n");
1173 ret = -E_WMA_OUTPUT_SPACE;
1174 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *data_size)
1176 /* single frame decode */
1177 ret = wma_decode_frame(pwd, samples);
1180 samples += pwd->ahi.channels * pwd->frame_len;
1182 PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
1183 pwd->frame_len, pwd->block_len,
1184 (int)((int8_t *)samples - (int8_t *)data), pwd->ahi.block_align);
1185 *data_size = (int8_t *)samples - (int8_t *)data;
1186 return pwd->ahi.block_align;
1188 /* reset the bit reservoir on errors */
1189 pwd->last_superframe_len = 0;
1193 static void wmadec_close(struct filter_node *fn)
1195 struct private_wmadec_data *pwd = fn->private_data;
1199 wmadec_cleanup(pwd);
1200 free(fn->private_data);
1201 fn->private_data = NULL;
1204 static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
1206 struct filter_node *fn = btr_context(btrn);
1207 struct private_wmadec_data *pwd = fn->private_data;
1209 return decoder_execute(cmd, pwd->ahi.sample_rate, pwd->ahi.channels,
1213 #define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
1215 static void wmadec_post_select(__a_unused struct sched *s, struct task *t)
1217 struct filter_node *fn = container_of(t, struct filter_node, task);
1219 struct private_wmadec_data *pwd = fn->private_data;
1220 struct btr_node *btrn = fn->btrn;
1227 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
1232 btr_merge(btrn, fn->min_iqs);
1233 len = btr_next_buffer(btrn, (char **)&in);
1234 ret = -E_WMADEC_EOF;
1235 if (len < fn->min_iqs)
1238 ret = wma_decode_init(in, len, &pwd);
1242 fn->min_iqs += 4096;
1245 fn->min_iqs = 2 * (WMA_FRAME_SKIP + pwd->ahi.block_align);
1246 fn->private_data = pwd;
1247 converted = pwd->ahi.header_len;
1250 fn->min_iqs = WMA_FRAME_SKIP + pwd->ahi.block_align;
1253 int out_size = WMA_OUTPUT_BUFFER_SIZE;
1254 if (converted + fn->min_iqs > len)
1256 out = para_malloc(WMA_OUTPUT_BUFFER_SIZE);
1257 ret = wma_decode_superframe(pwd, out,
1258 &out_size, (uint8_t *)in + converted + WMA_FRAME_SKIP,
1259 len - WMA_FRAME_SKIP);
1264 btr_add_output(out, out_size, btrn);
1265 converted += ret + WMA_FRAME_SKIP;
1268 btr_consume(btrn, converted);
1273 btr_remove_node(btrn);
1276 static void wmadec_open(struct filter_node *fn)
1278 fn->private_data = NULL;
1283 * The init function of the wma decoder.
1285 * \param f Its fields are filled in by the function.
1287 void wmadec_filter_init(struct filter *f)
1289 f->open = wmadec_open;
1290 f->close = wmadec_close;
1291 f->execute = wmadec_execute;
1292 f->pre_select = generic_filter_pre_select;
1293 f->post_select = wmadec_post_select;