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. */
76 int exponent_sizes[BLOCK_NB_SIZES];
77 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
78 /** The index of the first coef in high band. */
79 int high_band_start[BLOCK_NB_SIZES];
80 /** Maximal number of coded coefficients. */
81 int coefs_end[BLOCK_NB_SIZES];
82 int exponent_high_sizes[BLOCK_NB_SIZES];
83 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
86 /* coded values in high bands */
87 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
88 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
90 /* there are two possible tables for spectral coefficients */
91 struct vlc coef_vlc[2];
92 uint16_t *run_table[2];
93 uint16_t *level_table[2];
94 const struct coef_vlc_table *coef_vlcs[2];
95 /** Frame length in samples. */
97 /** log2 of frame_len. */
99 /** Number of block sizes. */
102 int reset_block_lengths;
103 /** log2 of current block length. */
105 /** log2 of next block length. */
106 int next_block_len_bits;
107 /** log2 of previous block length. */
108 int prev_block_len_bits;
109 /** Block length in samples. */
111 /** Current position in frame. */
113 /** True if mid/side stereo mode. */
115 /** True if channel is coded. */
116 uint8_t channel_coded[MAX_CHANNELS];
117 /** log2 ratio frame/exp. length. */
118 int exponents_bsize[MAX_CHANNELS];
120 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
121 float max_exponent[MAX_CHANNELS];
122 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
123 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
124 float output[BLOCK_MAX_SIZE * 2];
125 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
126 float *windows[BLOCK_NB_SIZES];
127 /** Output buffer for one frame and the last for IMDCT windowing. */
128 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
129 /** Last frame info. */
130 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
132 int last_superframe_len;
133 float noise_table[NOISE_TAB_SIZE];
135 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
136 /* lsp_to_curve tables */
137 float lsp_cos_table[BLOCK_MAX_SIZE];
138 float lsp_pow_e_table[256];
139 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
140 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
144 #define EXPMAX DIV_ROUND_UP(19, EXPVLCBITS)
146 #define HGAINVLCBITS 9
147 #define HGAINMAX DIV_ROUND_UP(13, HGAINVLCBITS)
150 #define VLCMAX DIV_ROUND_UP(22, VLCBITS)
152 #define SINE_WINDOW(x) static float sine_ ## x[x] __a_aligned(16)
161 static float *sine_windows[6] = {
162 sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
165 /* Generate a sine window. */
166 static void sine_window_init(float *window, int n)
170 for (i = 0; i < n; i++)
171 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
174 static void wmadec_cleanup(struct private_wmadec_data *pwd)
178 for (i = 0; i < pwd->nb_block_sizes; i++)
179 imdct_end(pwd->mdct_ctx[i]);
180 if (pwd->use_exp_vlc)
181 free_vlc(&pwd->exp_vlc);
182 if (pwd->use_noise_coding)
183 free_vlc(&pwd->hgain_vlc);
184 for (i = 0; i < 2; i++) {
185 free_vlc(&pwd->coef_vlc[i]);
186 free(pwd->run_table[i]);
187 free(pwd->level_table[i]);
191 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
192 uint16_t **plevel_table, const struct coef_vlc_table *vlc_table)
194 int n = vlc_table->n;
195 const uint8_t *table_bits = vlc_table->huffbits;
196 const uint32_t *table_codes = vlc_table->huffcodes;
197 const uint16_t *levels_table = vlc_table->levels;
198 uint16_t *run_table, *level_table;
199 int i, l, j, k, level;
201 init_vlc(vlc, VLCBITS, n, table_bits, table_codes, 4);
203 run_table = para_malloc(n * sizeof(uint16_t));
204 level_table = para_malloc(n * sizeof(uint16_t));
209 l = levels_table[k++];
210 for (j = 0; j < l; j++) {
212 level_table[i] = level;
217 *prun_table = run_table;
218 *plevel_table = level_table;
221 /* compute the scale factor band sizes for each MDCT block size */
222 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
225 struct asf_header_info *ahi = &pwd->ahi;
226 int a, b, pos, lpos, k, block_len, i, j, n;
227 const uint8_t *table;
229 for (k = 0; k < pwd->nb_block_sizes; k++) {
230 block_len = pwd->frame_len >> k;
233 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
235 if (ahi->sample_rate >= 44100)
236 table = exponent_band_44100[a];
237 else if (ahi->sample_rate >= 32000)
238 table = exponent_band_32000[a];
239 else if (ahi->sample_rate >= 22050)
240 table = exponent_band_22050[a];
244 for (i = 0; i < n; i++)
245 pwd->exponent_bands[k][i] = table[i];
246 pwd->exponent_sizes[k] = n;
250 for (i = 0; i < 25; i++) {
251 a = wma_critical_freqs[i];
252 b = ahi->sample_rate;
253 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
258 pwd->exponent_bands[k][j++] = pos - lpos;
259 if (pos >= block_len)
263 pwd->exponent_sizes[k] = j;
266 /* max number of coefs */
267 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
268 /* high freq computation */
269 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
270 / ahi->sample_rate + 0.5);
271 n = pwd->exponent_sizes[k];
274 for (i = 0; i < n; i++) {
277 pos += pwd->exponent_bands[k][i];
279 if (start < pwd->high_band_start[k])
280 start = pwd->high_band_start[k];
281 if (end > pwd->coefs_end[k])
282 end = pwd->coefs_end[k];
284 pwd->exponent_high_bands[k][j++] = end - start;
286 pwd->exponent_high_sizes[k] = j;
290 static int wma_init(struct private_wmadec_data *pwd)
293 float bps1, high_freq;
297 struct asf_header_info *ahi = &pwd->ahi;
298 int flags2 = ahi->flags2;
300 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
301 || ahi->channels <= 0 || ahi->channels > 8
302 || ahi->bit_rate <= 0)
303 return -E_WMA_BAD_PARAMS;
305 /* compute MDCT block size */
306 if (ahi->sample_rate <= 16000)
307 pwd->frame_len_bits = 9;
308 else if (ahi->sample_rate <= 22050)
309 pwd->frame_len_bits = 10;
311 pwd->frame_len_bits = 11;
312 pwd->frame_len = 1 << pwd->frame_len_bits;
313 if (pwd->use_variable_block_len) {
315 nb = ((flags2 >> 3) & 3) + 1;
316 if ((ahi->bit_rate / ahi->channels) >= 32000)
318 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
321 pwd->nb_block_sizes = nb + 1;
323 pwd->nb_block_sizes = 1;
325 /* init rate dependent parameters */
326 pwd->use_noise_coding = 1;
327 high_freq = ahi->sample_rate * 0.5;
329 /* wma2 rates are normalized */
330 sample_rate1 = ahi->sample_rate;
331 if (sample_rate1 >= 44100)
332 sample_rate1 = 44100;
333 else if (sample_rate1 >= 22050)
334 sample_rate1 = 22050;
335 else if (sample_rate1 >= 16000)
336 sample_rate1 = 16000;
337 else if (sample_rate1 >= 11025)
338 sample_rate1 = 11025;
339 else if (sample_rate1 >= 8000)
342 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
343 pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
345 * Compute high frequency value and choose if noise coding should be
349 if (ahi->channels == 2)
351 if (sample_rate1 == 44100) {
353 pwd->use_noise_coding = 0;
355 high_freq = high_freq * 0.4;
356 } else if (sample_rate1 == 22050) {
358 pwd->use_noise_coding = 0;
359 else if (bps1 >= 0.72)
360 high_freq = high_freq * 0.7;
362 high_freq = high_freq * 0.6;
363 } else if (sample_rate1 == 16000) {
365 high_freq = high_freq * 0.5;
367 high_freq = high_freq * 0.3;
368 } else if (sample_rate1 == 11025)
369 high_freq = high_freq * 0.7;
370 else if (sample_rate1 == 8000) {
372 high_freq = high_freq * 0.5;
374 pwd->use_noise_coding = 0;
376 high_freq = high_freq * 0.65;
379 high_freq = high_freq * 0.75;
381 high_freq = high_freq * 0.6;
383 high_freq = high_freq * 0.5;
385 PARA_INFO_LOG("channels=%d sample_rate=%d "
386 "bitrate=%d block_align=%d\n",
387 ahi->channels, ahi->sample_rate,
388 ahi->bit_rate, ahi->block_align);
389 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
390 "high_freq=%f bitoffset=%d\n",
391 pwd->frame_len, bps, bps1,
392 high_freq, pwd->byte_offset_bits);
393 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
394 pwd->use_noise_coding, pwd->use_exp_vlc, pwd->nb_block_sizes);
396 compute_scale_factor_band_sizes(pwd, high_freq);
397 /* init MDCT windows : simple sinus window */
398 for (i = 0; i < pwd->nb_block_sizes; i++) {
400 n = 1 << (pwd->frame_len_bits - i);
401 sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
402 pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
405 pwd->reset_block_lengths = 1;
407 if (pwd->use_noise_coding) {
408 /* init the noise generator */
409 if (pwd->use_exp_vlc)
410 pwd->noise_mult = 0.02;
412 pwd->noise_mult = 0.04;
418 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
419 for (i = 0; i < NOISE_TAB_SIZE; i++) {
420 seed = seed * 314159 + 1;
421 pwd->noise_table[i] = (float) ((int) seed) * norm;
426 /* choose the VLC tables for the coefficients */
428 if (ahi->sample_rate >= 32000) {
431 else if (bps1 < 1.16)
434 pwd->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
435 pwd->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
436 init_coef_vlc(&pwd->coef_vlc[0], &pwd->run_table[0], &pwd->level_table[0],
438 init_coef_vlc(&pwd->coef_vlc[1], &pwd->run_table[1], &pwd->level_table[1],
443 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd, int frame_len)
448 wdel = M_PI / frame_len;
449 for (i = 0; i < frame_len; i++)
450 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
452 /* tables for x^-0.25 computation */
453 for (i = 0; i < 256; i++) {
455 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
458 /* These two tables are needed to avoid two operations in pow_m1_4. */
460 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
461 m = (1 << LSP_POW_BITS) + i;
462 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
464 pwd->lsp_pow_m_table1[i] = 2 * a - b;
465 pwd->lsp_pow_m_table2[i] = b - a;
470 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
472 struct private_wmadec_data *pwd;
475 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
476 pwd = para_calloc(sizeof(*pwd));
477 ret = read_asf_header(initial_buf, len, &pwd->ahi);
483 pwd->use_exp_vlc = pwd->ahi.flags2 & 0x0001;
484 pwd->use_bit_reservoir = pwd->ahi.flags2 & 0x0002;
485 pwd->use_variable_block_len = pwd->ahi.flags2 & 0x0004;
491 for (i = 0; i < pwd->nb_block_sizes; i++) {
492 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
496 if (pwd->use_noise_coding) {
497 PARA_INFO_LOG("using noise coding\n");
498 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
499 sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
500 wma_hgain_huffcodes, 2);
503 if (pwd->use_exp_vlc) {
504 PARA_INFO_LOG("using exp_vlc\n");
505 init_vlc(&pwd->exp_vlc, EXPVLCBITS,
506 sizeof(wma_scale_huffbits), wma_scale_huffbits,
507 wma_scale_huffcodes, 4);
509 PARA_INFO_LOG("using curve\n");
510 wma_lsp_to_curve_init(pwd, pwd->frame_len);
513 return pwd->ahi.header_len;
517 * compute x^-0.25 with an exponent and mantissa table. We use linear
518 * interpolation to reduce the mantissa table size at a small speed
519 * expense (linear interpolation approximately doubles the number of
520 * bits of precision).
522 static inline float pow_m1_4(struct private_wmadec_data *pwd, float x)
533 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
534 /* build interpolation scale: 1 <= t < 2. */
535 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
536 a = pwd->lsp_pow_m_table1[m];
537 b = pwd->lsp_pow_m_table2[m];
538 return pwd->lsp_pow_e_table[e] * (a + b * t.f);
541 static void wma_lsp_to_curve(struct private_wmadec_data *pwd,
542 float *out, float *val_max_ptr, int n, float *lsp)
545 float p, q, w, v, val_max;
548 for (i = 0; i < n; i++) {
551 w = pwd->lsp_cos_table[i];
552 for (j = 1; j < NB_LSP_COEFS; j += 2) {
559 v = pow_m1_4(pwd, v);
564 *val_max_ptr = val_max;
567 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
568 static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
570 float lsp_coefs[NB_LSP_COEFS];
573 for (i = 0; i < NB_LSP_COEFS; i++) {
574 if (i == 0 || i >= 8)
575 val = get_bits(&pwd->gb, 3);
577 val = get_bits(&pwd->gb, 4);
578 lsp_coefs[i] = wma_lsp_codebook[i][val];
581 wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
582 pwd->block_len, lsp_coefs);
585 /* Decode exponents coded with VLC codes. */
586 static int decode_exp_vlc(struct private_wmadec_data *pwd, int ch)
588 int last_exp, n, code;
589 const uint16_t *ptr, *band_ptr;
590 float v, *q, max_scale, *q_end;
592 band_ptr = pwd->exponent_bands[pwd->frame_len_bits - pwd->block_len_bits];
594 q = pwd->exponents[ch];
595 q_end = q + pwd->block_len;
600 code = get_vlc(&pwd->gb, pwd->exp_vlc.table, EXPVLCBITS, EXPMAX);
603 /* NOTE: this offset is the same as MPEG4 AAC ! */
604 last_exp += code - 60;
605 /* XXX: use a table */
606 v = pow(10, last_exp * (1.0 / 16.0));
614 pwd->max_exponent[ch] = max_scale;
618 /* compute src0 * src1 + src2 */
619 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
620 const float *src2, int len)
624 for (i = 0; i < len; i++)
625 dst[i] = src0[i] * src1[i] + src2[i];
628 static inline void vector_mult_reverse(float *dst, const float *src0,
629 const float *src1, int len)
634 for (i = 0; i < len; i++)
635 dst[i] = src0[i] * src1[-i];
639 * Apply MDCT window and add into output.
641 * We ensure that when the windows overlap their squared sum
642 * is always 1 (MDCT reconstruction rule).
644 static void wma_window(struct private_wmadec_data *pwd, float *out)
646 float *in = pwd->output;
647 int block_len, bsize, n;
650 if (pwd->block_len_bits <= pwd->prev_block_len_bits) {
651 block_len = pwd->block_len;
652 bsize = pwd->frame_len_bits - pwd->block_len_bits;
653 vector_mult_add(out, in, pwd->windows[bsize], out, block_len);
655 block_len = 1 << pwd->prev_block_len_bits;
656 n = (pwd->block_len - block_len) / 2;
657 bsize = pwd->frame_len_bits - pwd->prev_block_len_bits;
658 vector_mult_add(out + n, in + n, pwd->windows[bsize], out + n,
660 memcpy(out + n + block_len, in + n + block_len,
663 out += pwd->block_len;
664 in += pwd->block_len;
666 if (pwd->block_len_bits <= pwd->next_block_len_bits) {
667 block_len = pwd->block_len;
668 bsize = pwd->frame_len_bits - pwd->block_len_bits;
669 vector_mult_reverse(out, in, pwd->windows[bsize], block_len);
671 block_len = 1 << pwd->next_block_len_bits;
672 n = (pwd->block_len - block_len) / 2;
673 bsize = pwd->frame_len_bits - pwd->next_block_len_bits;
674 memcpy(out, in, n * sizeof(float));
675 vector_mult_reverse(out + n, in + n, pwd->windows[bsize],
677 memset(out + n + block_len, 0, n * sizeof(float));
681 static int wma_total_gain_to_bits(int total_gain)
685 else if (total_gain < 32)
687 else if (total_gain < 40)
689 else if (total_gain < 45)
695 static int compute_high_band_values(struct private_wmadec_data *pwd,
696 int bsize, int nb_coefs[MAX_CHANNELS])
700 if (!pwd->use_noise_coding)
702 for (ch = 0; ch < pwd->ahi.channels; ch++) {
704 if (!pwd->channel_coded[ch])
706 m = pwd->exponent_high_sizes[bsize];
707 for (i = 0; i < m; i++) {
708 a = get_bit(&pwd->gb);
709 pwd->high_band_coded[ch][i] = a;
712 nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
715 for (ch = 0; ch < pwd->ahi.channels; ch++) {
717 if (!pwd->channel_coded[ch])
719 n = pwd->exponent_high_sizes[bsize];
720 val = (int)0x80000000;
721 for (i = 0; i < n; i++) {
722 if (!pwd->high_band_coded[ch][i])
724 if (val == (int)0x80000000)
725 val = get_bits(&pwd->gb, 7) - 19;
727 int code = get_vlc(&pwd->gb,
728 pwd->hgain_vlc.table, HGAINVLCBITS,
734 pwd->high_band_values[ch][i] = val;
740 static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
741 int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
744 float mdct_norm = 1.0 / (pwd->block_len / 2);
746 for (ch = 0; ch < pwd->ahi.channels; ch++) {
748 float *coefs, *exponents, mult, mult1, noise;
749 int i, j, n, n1, last_high_band, esize;
750 float exp_power[HIGH_BAND_MAX_SIZE];
752 if (!pwd->channel_coded[ch])
754 coefs1 = pwd->coefs1[ch];
755 exponents = pwd->exponents[ch];
756 esize = pwd->exponents_bsize[ch];
757 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
759 coefs = pwd->coefs[ch];
760 if (!pwd->use_noise_coding) {
761 /* XXX: optimize more */
763 for (i = 0; i < n; i++)
764 *coefs++ = coefs1[i] *
765 exponents[i << bsize >> esize] * mult;
766 n = pwd->block_len - pwd->coefs_end[bsize];
767 for (i = 0; i < n; i++)
771 n1 = pwd->exponent_high_sizes[bsize];
772 /* compute power of high bands */
773 exponents = pwd->exponents[ch] +
774 (pwd->high_band_start[bsize] << bsize);
775 last_high_band = 0; /* avoid warning */
776 for (j = 0; j < n1; j++) {
777 n = pwd->exponent_high_bands[
778 pwd->frame_len_bits - pwd->block_len_bits][j];
779 if (pwd->high_band_coded[ch][j]) {
782 for (i = 0; i < n; i++) {
783 val = exponents[i << bsize >> esize];
786 exp_power[j] = e2 / n;
789 exponents += n << bsize;
791 /* main freqs and high freqs */
792 exponents = pwd->exponents[ch];
793 for (j = -1; j < n1; j++) {
795 n = pwd->high_band_start[bsize];
797 n = pwd->exponent_high_bands[pwd->frame_len_bits
798 - pwd->block_len_bits][j];
799 if (j >= 0 && pwd->high_band_coded[ch][j]) {
800 /* use noise with specified power */
801 mult1 = sqrt(exp_power[j]
802 / exp_power[last_high_band]);
803 /* XXX: use a table */
804 mult1 *= pow(10, pwd->high_band_values[ch][j] * 0.05);
805 mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
807 for (i = 0; i < n; i++) {
808 noise = pwd->noise_table[pwd->noise_index];
809 pwd->noise_index = (pwd->noise_index + 1)
810 & (NOISE_TAB_SIZE - 1);
811 *coefs++ = noise * exponents[
812 i << bsize >> esize] * mult1;
814 exponents += n << bsize;
816 /* coded values + small noise */
817 for (i = 0; i < n; i++) {
818 noise = pwd->noise_table[pwd->noise_index];
819 pwd->noise_index = (pwd->noise_index + 1)
820 & (NOISE_TAB_SIZE - 1);
821 *coefs++ = ((*coefs1++) + noise) *
822 exponents[i << bsize >> esize]
825 exponents += n << bsize;
828 /* very high freqs: noise */
829 n = pwd->block_len - pwd->coefs_end[bsize];
830 mult1 = mult * exponents[((-1 << bsize)) >> esize];
831 for (i = 0; i < n; i++) {
832 *coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
833 pwd->noise_index = (pwd->noise_index + 1)
834 & (NOISE_TAB_SIZE - 1);
840 * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
843 static int wma_decode_block(struct private_wmadec_data *pwd)
845 int ret, n, v, ch, code, bsize;
846 int coef_nb_bits, total_gain;
847 int nb_coefs[MAX_CHANNELS];
849 /* compute current block length */
850 if (pwd->use_variable_block_len) {
851 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
853 if (pwd->reset_block_lengths) {
854 pwd->reset_block_lengths = 0;
855 v = get_bits(&pwd->gb, n);
856 if (v >= pwd->nb_block_sizes)
857 return -E_WMA_BLOCK_SIZE;
858 pwd->prev_block_len_bits = pwd->frame_len_bits - v;
859 v = get_bits(&pwd->gb, n);
860 if (v >= pwd->nb_block_sizes)
861 return -E_WMA_BLOCK_SIZE;
862 pwd->block_len_bits = pwd->frame_len_bits - v;
864 /* update block lengths */
865 pwd->prev_block_len_bits = pwd->block_len_bits;
866 pwd->block_len_bits = pwd->next_block_len_bits;
868 v = get_bits(&pwd->gb, n);
869 if (v >= pwd->nb_block_sizes)
870 return -E_WMA_BLOCK_SIZE;
871 pwd->next_block_len_bits = pwd->frame_len_bits - v;
873 /* fixed block len */
874 pwd->next_block_len_bits = pwd->frame_len_bits;
875 pwd->prev_block_len_bits = pwd->frame_len_bits;
876 pwd->block_len_bits = pwd->frame_len_bits;
879 /* now check if the block length is coherent with the frame length */
880 pwd->block_len = 1 << pwd->block_len_bits;
881 if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
882 return -E_INCOHERENT_BLOCK_LEN;
884 if (pwd->ahi.channels == 2)
885 pwd->ms_stereo = get_bit(&pwd->gb);
887 for (ch = 0; ch < pwd->ahi.channels; ch++) {
888 int a = get_bit(&pwd->gb);
889 pwd->channel_coded[ch] = a;
893 bsize = pwd->frame_len_bits - pwd->block_len_bits;
895 /* if no channel coded, no need to go further */
896 /* XXX: fix potential framing problems */
901 * Read total gain and extract corresponding number of bits for coef
906 int a = get_bits(&pwd->gb, 7);
912 coef_nb_bits = wma_total_gain_to_bits(total_gain);
914 /* compute number of coefficients */
915 n = pwd->coefs_end[bsize];
916 for (ch = 0; ch < pwd->ahi.channels; ch++)
919 ret = compute_high_band_values(pwd, bsize, nb_coefs);
923 /* exponents can be reused in short blocks. */
924 if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
925 for (ch = 0; ch < pwd->ahi.channels; ch++) {
926 if (pwd->channel_coded[ch]) {
927 if (pwd->use_exp_vlc) {
928 ret = decode_exp_vlc(pwd, ch);
932 decode_exp_lsp(pwd, ch);
933 pwd->exponents_bsize[ch] = bsize;
938 /* parse spectral coefficients : just RLE encoding */
939 for (ch = 0; ch < pwd->ahi.channels; ch++) {
940 struct vlc *coef_vlc;
941 int level, run, tindex;
943 const uint16_t *level_table, *run_table;
945 if (!pwd->channel_coded[ch])
948 * special VLC tables are used for ms stereo because there is
949 * potentially less energy there
951 tindex = (ch == 1 && pwd->ms_stereo);
952 coef_vlc = &pwd->coef_vlc[tindex];
953 run_table = pwd->run_table[tindex];
954 level_table = pwd->level_table[tindex];
956 ptr = &pwd->coefs1[ch][0];
957 eptr = ptr + nb_coefs[ch];
958 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
960 code = get_vlc(&pwd->gb, coef_vlc->table,
964 if (code == 1) /* EOB */
966 if (code == 0) { /* escape */
967 level = get_bits(&pwd->gb, coef_nb_bits);
968 /* reading block_len_bits would be better */
969 run = get_bits(&pwd->gb, pwd->frame_len_bits);
970 } else { /* normal code */
971 run = run_table[code];
972 level = level_table[code];
974 if (!get_bit(&pwd->gb))
978 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
982 if (ptr >= eptr) /* EOB can be omitted */
986 compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
987 if (pwd->ms_stereo && pwd->channel_coded[1]) {
991 * Nominal case for ms stereo: we do it before mdct.
993 * No need to optimize this case because it should almost never
996 if (!pwd->channel_coded[0]) {
997 PARA_NOTICE_LOG("rare ms-stereo\n");
998 memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
999 pwd->channel_coded[0] = 1;
1001 for (i = 0; i < pwd->block_len; i++) {
1002 a = pwd->coefs[0][i];
1003 b = pwd->coefs[1][i];
1004 pwd->coefs[0][i] = a + b;
1005 pwd->coefs[1][i] = a - b;
1009 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1012 n4 = pwd->block_len / 2;
1013 if (pwd->channel_coded[ch])
1014 imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
1015 else if (!(pwd->ms_stereo && ch == 1))
1016 memset(pwd->output, 0, sizeof(pwd->output));
1018 /* multiply by the window and add in the frame */
1019 idx = (pwd->frame_len / 2) + pwd->block_pos - n4;
1020 wma_window(pwd, &pwd->frame_out[ch][idx]);
1023 /* update block number */
1024 pwd->block_pos += pwd->block_len;
1025 if (pwd->block_pos >= pwd->frame_len)
1032 * Clip a signed integer value into the -32768,32767 range.
1034 * \param a The value to clip.
1036 * \return The clipped value.
1038 static inline int16_t av_clip_int16(int a)
1040 if ((a + 32768) & ~65535)
1041 return (a >> 31) ^ 32767;
1046 /* Decode a frame of frame_len samples. */
1047 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1049 int ret, i, n, ch, incr;
1053 /* read each block */
1056 ret = wma_decode_block(pwd);
1063 /* convert frame to integer */
1065 incr = pwd->ahi.channels;
1066 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1068 iptr = pwd->frame_out[ch];
1070 for (i = 0; i < n; i++) {
1071 *ptr = av_clip_int16(lrintf(*iptr++));
1074 /* prepare for next block */
1075 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1076 pwd->frame_len * sizeof(float));
1081 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
1082 int *data_size, const uint8_t *buf, int buf_size)
1087 if (buf_size == 0) {
1088 pwd->last_superframe_len = 0;
1091 if (buf_size < pwd->ahi.block_align)
1093 buf_size = pwd->ahi.block_align;
1095 init_get_bits(&pwd->gb, buf, buf_size);
1096 if (pwd->use_bit_reservoir) {
1097 int i, nb_frames, bit_offset, pos, len;
1100 /* read super frame header */
1101 skip_bits(&pwd->gb, 4); /* super frame index */
1102 nb_frames = get_bits(&pwd->gb, 4) - 1;
1103 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1104 ret = -E_WMA_OUTPUT_SPACE;
1105 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1106 * sizeof(int16_t) > *data_size)
1109 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1111 if (pwd->last_superframe_len > 0) {
1112 /* add bit_offset bits to last frame */
1113 ret = -E_WMA_BAD_SUPERFRAME;
1114 if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1115 MAX_CODED_SUPERFRAME_SIZE)
1117 q = pwd->last_superframe + pwd->last_superframe_len;
1120 *q++ = get_bits(&pwd->gb, 8);
1124 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1126 /* XXX: bit_offset bits into last frame */
1127 init_get_bits(&pwd->gb, pwd->last_superframe,
1128 MAX_CODED_SUPERFRAME_SIZE);
1129 /* skip unused bits */
1130 if (pwd->last_bitoffset > 0)
1131 skip_bits(&pwd->gb, pwd->last_bitoffset);
1133 * This frame is stored in the last superframe and in
1136 ret = wma_decode_frame(pwd, samples);
1139 samples += pwd->ahi.channels * pwd->frame_len;
1142 /* read each frame starting from bit_offset */
1143 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1144 init_get_bits(&pwd->gb, buf + (pos >> 3),
1145 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1148 skip_bits(&pwd->gb, len);
1150 pwd->reset_block_lengths = 1;
1151 for (i = 0; i < nb_frames; i++) {
1152 ret = wma_decode_frame(pwd, samples);
1155 samples += pwd->ahi.channels * pwd->frame_len;
1158 /* we copy the end of the frame in the last frame buffer */
1159 pos = get_bits_count(&pwd->gb) +
1160 ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1161 pwd->last_bitoffset = pos & 7;
1163 len = buf_size - pos;
1164 ret = -E_WMA_BAD_SUPERFRAME;
1165 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1167 pwd->last_superframe_len = len;
1168 memcpy(pwd->last_superframe, buf + pos, len);
1170 PARA_DEBUG_LOG("not using bit reservoir\n");
1171 ret = -E_WMA_OUTPUT_SPACE;
1172 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *data_size)
1174 /* single frame decode */
1175 ret = wma_decode_frame(pwd, samples);
1178 samples += pwd->ahi.channels * pwd->frame_len;
1180 PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
1181 pwd->frame_len, pwd->block_len,
1182 (int)((int8_t *)samples - (int8_t *)data), pwd->ahi.block_align);
1183 *data_size = (int8_t *)samples - (int8_t *)data;
1184 return pwd->ahi.block_align;
1186 /* reset the bit reservoir on errors */
1187 pwd->last_superframe_len = 0;
1191 static void wmadec_close(struct filter_node *fn)
1193 struct private_wmadec_data *pwd = fn->private_data;
1197 wmadec_cleanup(pwd);
1198 free(fn->private_data);
1199 fn->private_data = NULL;
1202 static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
1204 struct filter_node *fn = btr_context(btrn);
1205 struct private_wmadec_data *pwd = fn->private_data;
1207 return decoder_execute(cmd, pwd->ahi.sample_rate, pwd->ahi.channels,
1211 #define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
1213 static void wmadec_post_select(__a_unused struct sched *s, struct task *t)
1215 struct filter_node *fn = container_of(t, struct filter_node, task);
1217 struct private_wmadec_data *pwd = fn->private_data;
1218 struct btr_node *btrn = fn->btrn;
1225 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
1230 btr_merge(btrn, fn->min_iqs);
1231 len = btr_next_buffer(btrn, (char **)&in);
1232 ret = -E_WMADEC_EOF;
1233 if (len < fn->min_iqs)
1236 ret = wma_decode_init(in, len, &pwd);
1240 fn->min_iqs += 4096;
1243 fn->min_iqs = 2 * (WMA_FRAME_SKIP + pwd->ahi.block_align);
1244 fn->private_data = pwd;
1245 converted = pwd->ahi.header_len;
1248 fn->min_iqs = WMA_FRAME_SKIP + pwd->ahi.block_align;
1251 int out_size = WMA_OUTPUT_BUFFER_SIZE;
1252 if (converted + fn->min_iqs > len)
1254 out = para_malloc(WMA_OUTPUT_BUFFER_SIZE);
1255 ret = wma_decode_superframe(pwd, out,
1256 &out_size, (uint8_t *)in + converted + WMA_FRAME_SKIP,
1257 len - WMA_FRAME_SKIP);
1262 btr_add_output(out, out_size, btrn);
1263 converted += ret + WMA_FRAME_SKIP;
1266 btr_consume(btrn, converted);
1271 btr_remove_node(btrn);
1274 static void wmadec_open(struct filter_node *fn)
1276 fn->private_data = NULL;
1281 * The init function of the wma decoder.
1283 * \param f Its fields are filled in by the function.
1285 void wmadec_filter_init(struct filter *f)
1287 f->open = wmadec_open;
1288 f->close = wmadec_close;
1289 f->execute = wmadec_execute;
1290 f->pre_select = generic_filter_pre_select;
1291 f->post_select = wmadec_post_select;