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
22 #include <sys/select.h>
30 #include "buffer_tree.h"
32 #include "portable_io.h"
33 #include "bitstream.h"
40 #define BLOCK_MIN_BITS 7
41 #define BLOCK_MAX_BITS 11
42 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
44 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
46 /* XXX: find exact max size */
47 #define HIGH_BAND_MAX_SIZE 16
49 /* XXX: is it a suitable value ? */
50 #define MAX_CODED_SUPERFRAME_SIZE 16384
52 #define MAX_CHANNELS 2
54 #define NOISE_TAB_SIZE 8192
56 #define LSP_POW_BITS 7
58 struct private_wmadec_data {
59 /** Information contained in the audio file header. */
60 struct asf_header_info ahi;
61 struct getbit_context gb;
62 /** Whether perceptual noise is added. */
64 /** Depends on number of the bits per second and the frame length. */
66 /** Only used if ahi->use_exp_vlc is true. */
68 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
69 /** The index of the first coef in high band. */
70 int high_band_start[BLOCK_NB_SIZES];
71 /** Maximal number of coded coefficients. */
72 int coefs_end[BLOCK_NB_SIZES];
73 int exponent_high_sizes[BLOCK_NB_SIZES];
74 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
77 /* coded values in high bands */
78 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
79 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
81 /* there are two possible tables for spectral coefficients */
82 struct vlc coef_vlc[2];
83 uint16_t *run_table[2];
84 uint16_t *level_table[2];
85 const struct coef_vlc_table *coef_vlcs[2];
86 /** Frame length in samples. */
88 /** log2 of frame_len. */
90 /** Number of block sizes, one if !ahi->use_variable_block_len. */
92 /* Whether to update block lengths from getbit context. */
93 bool reset_block_lengths;
94 /** log2 of current block length. */
96 /** log2 of next block length. */
97 int next_block_len_bits;
98 /** log2 of previous block length. */
99 int prev_block_len_bits;
100 /** Block length in samples. */
102 /** Current position in frame. */
104 /** True if mid/side stereo mode. */
106 /** True if channel is coded. */
107 uint8_t channel_coded[MAX_CHANNELS];
108 /** log2 ratio frame/exp. length. */
109 int exponents_bsize[MAX_CHANNELS];
111 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
112 float max_exponent[MAX_CHANNELS];
113 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
114 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
115 float output[BLOCK_MAX_SIZE * 2];
116 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
117 float *windows[BLOCK_NB_SIZES];
118 /** Output buffer for one frame and the last for IMDCT windowing. */
119 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
120 /** Last frame info. */
121 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
123 int last_superframe_len;
124 float noise_table[NOISE_TAB_SIZE];
126 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
127 /* lsp_to_curve tables */
128 float lsp_cos_table[BLOCK_MAX_SIZE];
129 float lsp_pow_e_table[256];
130 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
131 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
135 #define HGAINVLCBITS 9
138 /** \cond sine_winows */
140 #define SINE_WINDOW(x) static float sine_ ## x[x] __a_aligned(16)
149 static float *sine_windows[6] = {
150 sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
152 /** \endcond sine_windows */
154 /* Generate a sine window. */
155 static void sine_window_init(float *window, int n)
159 for (i = 0; i < n; i++)
160 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
163 static void wmadec_cleanup(struct private_wmadec_data *pwd)
167 for (i = 0; i < pwd->nb_block_sizes; i++)
168 imdct_end(pwd->mdct_ctx[i]);
169 if (pwd->ahi.use_exp_vlc)
170 free_vlc(&pwd->exp_vlc);
171 if (pwd->use_noise_coding)
172 free_vlc(&pwd->hgain_vlc);
173 for (i = 0; i < 2; i++) {
174 free_vlc(&pwd->coef_vlc[i]);
175 free(pwd->run_table[i]);
176 free(pwd->level_table[i]);
180 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
181 uint16_t **plevel_table, const struct coef_vlc_table *vlc_table)
183 int n = vlc_table->n;
184 const uint8_t *table_bits = vlc_table->huffbits;
185 const uint32_t *table_codes = vlc_table->huffcodes;
186 const uint16_t *levels_table = vlc_table->levels;
187 uint16_t *run_table, *level_table;
188 int i, l, j, k, level;
190 init_vlc(vlc, VLCBITS, n, table_bits, table_codes, 4);
192 run_table = para_malloc(n * sizeof(uint16_t));
193 level_table = para_malloc(n * sizeof(uint16_t));
198 l = levels_table[k++];
199 for (j = 0; j < l; j++) {
201 level_table[i] = level;
206 *prun_table = run_table;
207 *plevel_table = level_table;
210 /* compute the scale factor band sizes for each MDCT block size */
211 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
214 struct asf_header_info *ahi = &pwd->ahi;
215 int a, b, pos, lpos, k, block_len, i, j, n;
216 const uint8_t *table;
218 for (k = 0; k < pwd->nb_block_sizes; k++) {
221 block_len = pwd->frame_len >> k;
223 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
225 if (ahi->sample_rate >= 44100)
226 table = exponent_band_44100[a];
227 else if (ahi->sample_rate >= 32000)
228 table = exponent_band_32000[a];
229 else if (ahi->sample_rate >= 22050)
230 table = exponent_band_22050[a];
234 for (i = 0; i < n; i++)
235 pwd->exponent_bands[k][i] = table[i];
240 for (i = 0; i < 25; i++) {
241 a = wma_critical_freqs[i];
242 b = ahi->sample_rate;
243 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
248 pwd->exponent_bands[k][j++] = pos - lpos;
249 if (pos >= block_len)
256 /* max number of coefs */
257 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
258 /* high freq computation */
259 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
260 / ahi->sample_rate + 0.5);
264 for (i = 0; i < n; i++) {
267 pos += pwd->exponent_bands[k][i];
269 if (start < pwd->high_band_start[k])
270 start = pwd->high_band_start[k];
271 if (end > pwd->coefs_end[k])
272 end = pwd->coefs_end[k];
274 pwd->exponent_high_bands[k][j++] = end - start;
276 pwd->exponent_high_sizes[k] = j;
280 static int wma_init(struct private_wmadec_data *pwd)
283 float bps1, high_freq;
287 struct asf_header_info *ahi = &pwd->ahi;
288 int flags2 = ahi->flags2;
290 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
291 || ahi->channels <= 0 || ahi->channels > 8
292 || ahi->bit_rate <= 0)
293 return -E_WMA_BAD_PARAMS;
295 /* compute MDCT block size */
296 if (ahi->sample_rate <= 16000)
297 pwd->frame_len_bits = 9;
298 else if (ahi->sample_rate <= 22050)
299 pwd->frame_len_bits = 10;
301 pwd->frame_len_bits = 11;
302 pwd->frame_len = 1 << pwd->frame_len_bits;
303 if (pwd->ahi.use_variable_block_len) {
305 nb = ((flags2 >> 3) & 3) + 1;
306 if ((ahi->bit_rate / ahi->channels) >= 32000)
308 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
311 pwd->nb_block_sizes = nb + 1;
313 pwd->nb_block_sizes = 1;
315 /* init rate dependent parameters */
316 pwd->use_noise_coding = 1;
317 high_freq = ahi->sample_rate * 0.5;
319 /* wma2 rates are normalized */
320 sample_rate1 = ahi->sample_rate;
321 if (sample_rate1 >= 44100)
322 sample_rate1 = 44100;
323 else if (sample_rate1 >= 22050)
324 sample_rate1 = 22050;
325 else if (sample_rate1 >= 16000)
326 sample_rate1 = 16000;
327 else if (sample_rate1 >= 11025)
328 sample_rate1 = 11025;
329 else if (sample_rate1 >= 8000)
332 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
333 pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
335 * Compute high frequency value and choose if noise coding should be
339 if (ahi->channels == 2)
341 if (sample_rate1 == 44100) {
343 pwd->use_noise_coding = 0;
345 high_freq = high_freq * 0.4;
346 } else if (sample_rate1 == 22050) {
348 pwd->use_noise_coding = 0;
349 else if (bps1 >= 0.72)
350 high_freq = high_freq * 0.7;
352 high_freq = high_freq * 0.6;
353 } else if (sample_rate1 == 16000) {
355 high_freq = high_freq * 0.5;
357 high_freq = high_freq * 0.3;
358 } else if (sample_rate1 == 11025)
359 high_freq = high_freq * 0.7;
360 else if (sample_rate1 == 8000) {
362 high_freq = high_freq * 0.5;
364 pwd->use_noise_coding = 0;
366 high_freq = high_freq * 0.65;
369 high_freq = high_freq * 0.75;
371 high_freq = high_freq * 0.6;
373 high_freq = high_freq * 0.5;
375 PARA_INFO_LOG("channels=%u sample_rate=%u "
376 "bitrate=%u block_align=%d\n",
377 ahi->channels, ahi->sample_rate,
378 ahi->bit_rate, ahi->block_align);
379 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
380 "high_freq=%f bitoffset=%d\n",
381 pwd->frame_len, bps, bps1,
382 high_freq, pwd->byte_offset_bits);
383 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
384 pwd->use_noise_coding, pwd->ahi.use_exp_vlc, pwd->nb_block_sizes);
386 compute_scale_factor_band_sizes(pwd, high_freq);
387 /* init MDCT windows : simple sinus window */
388 for (i = 0; i < pwd->nb_block_sizes; i++) {
390 n = 1 << (pwd->frame_len_bits - i);
391 sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
392 pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
395 pwd->reset_block_lengths = true;
397 if (pwd->use_noise_coding) {
398 /* init the noise generator */
399 if (pwd->ahi.use_exp_vlc)
400 pwd->noise_mult = 0.02;
402 pwd->noise_mult = 0.04;
408 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
409 for (i = 0; i < NOISE_TAB_SIZE; i++) {
410 seed = seed * 314159 + 1;
411 pwd->noise_table[i] = (float) ((int) seed) * norm;
416 /* choose the VLC tables for the coefficients */
418 if (ahi->sample_rate >= 32000) {
421 else if (bps1 < 1.16)
424 pwd->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
425 pwd->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
426 init_coef_vlc(&pwd->coef_vlc[0], &pwd->run_table[0], &pwd->level_table[0],
428 init_coef_vlc(&pwd->coef_vlc[1], &pwd->run_table[1], &pwd->level_table[1],
433 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd)
438 wdel = M_PI / pwd->frame_len;
439 for (i = 0; i < pwd->frame_len; i++)
440 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
442 /* tables for x^-0.25 computation */
443 for (i = 0; i < 256; i++) {
445 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
448 /* These two tables are needed to avoid two operations in pow_m1_4. */
450 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
451 m = (1 << LSP_POW_BITS) + i;
452 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
454 pwd->lsp_pow_m_table1[i] = 2 * a - b;
455 pwd->lsp_pow_m_table2[i] = b - a;
460 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
462 struct private_wmadec_data *pwd;
465 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
466 pwd = para_calloc(sizeof(*pwd));
467 ret = read_asf_header(initial_buf, len, &pwd->ahi);
477 for (i = 0; i < pwd->nb_block_sizes; i++) {
478 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
482 if (pwd->use_noise_coding) {
483 PARA_INFO_LOG("using noise coding\n");
484 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
485 sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
486 wma_hgain_huffcodes, 2);
489 if (pwd->ahi.use_exp_vlc) {
490 PARA_INFO_LOG("using exp_vlc\n");
491 init_vlc(&pwd->exp_vlc, EXPVLCBITS, sizeof(wma_scale_huffbits),
492 wma_scale_huffbits, wma_scale_huffcodes, 4);
494 PARA_INFO_LOG("using curve\n");
495 wma_lsp_to_curve_init(pwd);
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] = 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);
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)
680 static int compute_high_band_values(struct private_wmadec_data *pwd,
681 int bsize, int nb_coefs[MAX_CHANNELS])
685 if (!pwd->use_noise_coding)
687 for (ch = 0; ch < pwd->ahi.channels; ch++) {
689 if (!pwd->channel_coded[ch])
691 m = pwd->exponent_high_sizes[bsize];
692 for (i = 0; i < m; i++) {
693 a = get_bit(&pwd->gb);
694 pwd->high_band_coded[ch][i] = a;
697 nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
700 for (ch = 0; ch < pwd->ahi.channels; ch++) {
702 if (!pwd->channel_coded[ch])
704 n = pwd->exponent_high_sizes[bsize];
705 val = (int)0x80000000;
706 for (i = 0; i < n; i++) {
707 if (!pwd->high_band_coded[ch][i])
709 if (val == (int)0x80000000)
710 val = get_bits(&pwd->gb, 7) - 19;
712 int code = get_vlc(&pwd->gb,
713 pwd->hgain_vlc.table, HGAINVLCBITS);
718 pwd->high_band_values[ch][i] = val;
724 static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
725 int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
728 float mdct_norm = 1.0 / (pwd->block_len / 2);
730 for (ch = 0; ch < pwd->ahi.channels; ch++) {
732 float *coefs, *exponents, mult, mult1, noise;
733 int i, j, n, n1, last_high_band, esize;
734 float exp_power[HIGH_BAND_MAX_SIZE];
736 if (!pwd->channel_coded[ch])
738 coefs1 = pwd->coefs1[ch];
739 exponents = pwd->exponents[ch];
740 esize = pwd->exponents_bsize[ch];
741 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
743 coefs = pwd->coefs[ch];
744 if (!pwd->use_noise_coding) {
745 /* XXX: optimize more */
747 for (i = 0; i < n; i++)
748 *coefs++ = coefs1[i] *
749 exponents[i << bsize >> esize] * mult;
750 n = pwd->block_len - pwd->coefs_end[bsize];
751 for (i = 0; i < n; i++)
755 n1 = pwd->exponent_high_sizes[bsize];
756 /* compute power of high bands */
757 exponents = pwd->exponents[ch] +
758 (pwd->high_band_start[bsize] << bsize);
759 last_high_band = 0; /* avoid warning */
760 for (j = 0; j < n1; j++) {
761 n = pwd->exponent_high_bands[
762 pwd->frame_len_bits - pwd->block_len_bits][j];
763 if (pwd->high_band_coded[ch][j]) {
766 for (i = 0; i < n; i++) {
767 val = exponents[i << bsize >> esize];
770 exp_power[j] = e2 / n;
773 exponents += n << bsize;
775 /* main freqs and high freqs */
776 exponents = pwd->exponents[ch];
777 for (j = -1; j < n1; j++) {
779 n = pwd->high_band_start[bsize];
781 n = pwd->exponent_high_bands[pwd->frame_len_bits
782 - pwd->block_len_bits][j];
783 if (j >= 0 && pwd->high_band_coded[ch][j]) {
784 /* use noise with specified power */
785 mult1 = sqrt(exp_power[j]
786 / exp_power[last_high_band]);
787 /* XXX: use a table */
788 mult1 *= pow(10, pwd->high_band_values[ch][j] * 0.05);
789 mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
791 for (i = 0; i < n; i++) {
792 noise = pwd->noise_table[pwd->noise_index];
793 pwd->noise_index = (pwd->noise_index + 1)
794 & (NOISE_TAB_SIZE - 1);
795 *coefs++ = noise * exponents[
796 i << bsize >> esize] * mult1;
798 exponents += n << bsize;
800 /* coded values + small noise */
801 for (i = 0; i < n; i++) {
802 noise = pwd->noise_table[pwd->noise_index];
803 pwd->noise_index = (pwd->noise_index + 1)
804 & (NOISE_TAB_SIZE - 1);
805 *coefs++ = ((*coefs1++) + noise) *
806 exponents[i << bsize >> esize]
809 exponents += n << bsize;
812 /* very high freqs: noise */
813 n = pwd->block_len - pwd->coefs_end[bsize];
814 mult1 = mult * exponents[(-(1 << bsize)) >> esize];
815 for (i = 0; i < n; i++) {
816 *coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
817 pwd->noise_index = (pwd->noise_index + 1)
818 & (NOISE_TAB_SIZE - 1);
824 * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
827 static int wma_decode_block(struct private_wmadec_data *pwd)
829 int ret, n, v, ch, code, bsize;
830 int coef_nb_bits, total_gain;
831 int nb_coefs[MAX_CHANNELS];
833 /* compute current block length */
834 if (pwd->ahi.use_variable_block_len) {
835 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
837 if (pwd->reset_block_lengths) {
838 pwd->reset_block_lengths = false;
839 v = get_bits(&pwd->gb, n);
840 if (v >= pwd->nb_block_sizes)
841 return -E_WMA_BLOCK_SIZE;
842 pwd->prev_block_len_bits = pwd->frame_len_bits - v;
843 v = get_bits(&pwd->gb, n);
844 if (v >= pwd->nb_block_sizes)
845 return -E_WMA_BLOCK_SIZE;
846 pwd->block_len_bits = pwd->frame_len_bits - v;
848 /* update block lengths */
849 pwd->prev_block_len_bits = pwd->block_len_bits;
850 pwd->block_len_bits = pwd->next_block_len_bits;
852 v = get_bits(&pwd->gb, n);
853 if (v >= pwd->nb_block_sizes)
854 return -E_WMA_BLOCK_SIZE;
855 pwd->next_block_len_bits = pwd->frame_len_bits - v;
857 /* fixed block len */
858 pwd->next_block_len_bits = pwd->frame_len_bits;
859 pwd->prev_block_len_bits = pwd->frame_len_bits;
860 pwd->block_len_bits = pwd->frame_len_bits;
863 /* now check if the block length is coherent with the frame length */
864 pwd->block_len = 1 << pwd->block_len_bits;
865 if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
866 return -E_INCOHERENT_BLOCK_LEN;
868 if (pwd->ahi.channels == 2)
869 pwd->ms_stereo = get_bit(&pwd->gb);
871 for (ch = 0; ch < pwd->ahi.channels; ch++) {
872 int a = get_bit(&pwd->gb);
873 pwd->channel_coded[ch] = a;
877 bsize = pwd->frame_len_bits - pwd->block_len_bits;
879 /* if no channel coded, no need to go further */
880 /* XXX: fix potential framing problems */
885 * Read total gain and extract corresponding number of bits for coef
890 int a = get_bits(&pwd->gb, 7);
896 coef_nb_bits = wma_total_gain_to_bits(total_gain);
898 /* compute number of coefficients */
899 n = pwd->coefs_end[bsize];
900 for (ch = 0; ch < pwd->ahi.channels; ch++)
903 ret = compute_high_band_values(pwd, bsize, nb_coefs);
907 /* exponents can be reused in short blocks. */
908 if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
909 for (ch = 0; ch < pwd->ahi.channels; ch++) {
910 if (pwd->channel_coded[ch]) {
911 if (pwd->ahi.use_exp_vlc) {
912 ret = decode_exp_vlc(pwd, ch);
916 decode_exp_lsp(pwd, ch);
917 pwd->exponents_bsize[ch] = bsize;
922 /* parse spectral coefficients : just RLE encoding */
923 for (ch = 0; ch < pwd->ahi.channels; ch++) {
924 struct vlc *coef_vlc;
925 int level, run, tindex;
927 const uint16_t *level_table, *run_table;
929 if (!pwd->channel_coded[ch])
932 * special VLC tables are used for ms stereo because there is
933 * potentially less energy there
935 tindex = (ch == 1 && pwd->ms_stereo);
936 coef_vlc = &pwd->coef_vlc[tindex];
937 run_table = pwd->run_table[tindex];
938 level_table = pwd->level_table[tindex];
940 ptr = &pwd->coefs1[ch][0];
941 eptr = ptr + nb_coefs[ch];
942 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
944 code = get_vlc(&pwd->gb, coef_vlc->table, VLCBITS);
947 if (code == 1) /* EOB */
949 if (code == 0) { /* escape */
950 level = get_bits(&pwd->gb, coef_nb_bits);
951 /* reading block_len_bits would be better */
952 run = get_bits(&pwd->gb, pwd->frame_len_bits);
953 } else { /* normal code */
954 run = run_table[code];
955 level = level_table[code];
957 if (!get_bit(&pwd->gb))
961 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
965 if (ptr >= eptr) /* EOB can be omitted */
969 compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
970 if (pwd->ms_stereo && pwd->channel_coded[1]) {
974 * Nominal case for ms stereo: we do it before mdct.
976 * No need to optimize this case because it should almost never
979 if (!pwd->channel_coded[0]) {
980 PARA_NOTICE_LOG("rare ms-stereo\n");
981 memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
982 pwd->channel_coded[0] = 1;
984 for (i = 0; i < pwd->block_len; i++) {
985 a = pwd->coefs[0][i];
986 b = pwd->coefs[1][i];
987 pwd->coefs[0][i] = a + b;
988 pwd->coefs[1][i] = a - b;
992 for (ch = 0; ch < pwd->ahi.channels; ch++) {
995 n4 = pwd->block_len / 2;
996 if (pwd->channel_coded[ch])
997 imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
998 else if (!(pwd->ms_stereo && ch == 1))
999 memset(pwd->output, 0, sizeof(pwd->output));
1001 /* multiply by the window and add in the frame */
1002 idx = (pwd->frame_len / 2) + pwd->block_pos - n4;
1003 wma_window(pwd, &pwd->frame_out[ch][idx]);
1006 /* update block number */
1007 pwd->block_pos += pwd->block_len;
1008 if (pwd->block_pos >= pwd->frame_len)
1015 * Clip a signed integer value into the -32768,32767 range.
1017 * \param a The value to clip.
1019 * \return The clipped value.
1021 static inline int16_t av_clip_int16(int a)
1023 if ((a + 32768) & ~65535)
1024 return (a >> 31) ^ 32767;
1029 /* Decode a frame of frame_len samples. */
1030 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1036 /* read each block */
1039 ret = wma_decode_block(pwd);
1046 /* convert frame to integer */
1047 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1049 iptr = pwd->frame_out[ch];
1051 for (i = 0; i < pwd->frame_len; i++) {
1052 *ptr = av_clip_int16(lrintf(*iptr++));
1053 ptr += pwd->ahi.channels;
1055 /* prepare for next block */
1056 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1057 pwd->frame_len * sizeof(float));
1062 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
1063 int *data_size, const uint8_t *buf, int buf_size)
1068 if (buf_size == 0) {
1069 pwd->last_superframe_len = 0;
1073 if (buf_size < pwd->ahi.block_align) {
1077 buf_size = pwd->ahi.block_align;
1079 init_get_bits(&pwd->gb, buf, buf_size);
1080 if (pwd->ahi.use_bit_reservoir) {
1081 int i, nb_frames, bit_offset, pos, len;
1084 /* read super frame header */
1085 skip_bits(&pwd->gb, 4); /* super frame index */
1086 nb_frames = get_bits(&pwd->gb, 4) - 1;
1087 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1088 ret = -E_WMA_OUTPUT_SPACE;
1089 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1090 * sizeof(int16_t) > *data_size)
1093 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1095 if (pwd->last_superframe_len > 0) {
1096 /* add bit_offset bits to last frame */
1097 ret = -E_WMA_BAD_SUPERFRAME;
1098 if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1099 MAX_CODED_SUPERFRAME_SIZE)
1101 q = pwd->last_superframe + pwd->last_superframe_len;
1104 *q++ = get_bits(&pwd->gb, 8);
1108 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1110 /* XXX: bit_offset bits into last frame */
1111 init_get_bits(&pwd->gb, pwd->last_superframe,
1112 MAX_CODED_SUPERFRAME_SIZE);
1113 /* skip unused bits */
1114 if (pwd->last_bitoffset > 0)
1115 skip_bits(&pwd->gb, pwd->last_bitoffset);
1117 * This frame is stored in the last superframe and in
1120 ret = wma_decode_frame(pwd, samples);
1123 samples += pwd->ahi.channels * pwd->frame_len;
1126 /* read each frame starting from bit_offset */
1127 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1128 init_get_bits(&pwd->gb, buf + (pos >> 3),
1129 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1132 skip_bits(&pwd->gb, len);
1134 pwd->reset_block_lengths = true;
1135 for (i = 0; i < nb_frames; i++) {
1136 ret = wma_decode_frame(pwd, samples);
1139 samples += pwd->ahi.channels * pwd->frame_len;
1142 /* we copy the end of the frame in the last frame buffer */
1143 pos = get_bits_count(&pwd->gb) +
1144 ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1145 pwd->last_bitoffset = pos & 7;
1147 len = buf_size - pos;
1148 ret = -E_WMA_BAD_SUPERFRAME;
1149 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1151 pwd->last_superframe_len = len;
1152 memcpy(pwd->last_superframe, buf + pos, len);
1154 PARA_DEBUG_LOG("not using bit reservoir\n");
1155 ret = -E_WMA_OUTPUT_SPACE;
1156 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *data_size)
1158 /* single frame decode */
1159 ret = wma_decode_frame(pwd, samples);
1162 samples += pwd->ahi.channels * pwd->frame_len;
1164 PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
1165 pwd->frame_len, pwd->block_len,
1166 (int)((int8_t *)samples - (int8_t *)data), pwd->ahi.block_align);
1167 *data_size = (int8_t *)samples - (int8_t *)data;
1168 return pwd->ahi.block_align;
1170 /* reset the bit reservoir on errors */
1171 pwd->last_superframe_len = 0;
1175 static void wmadec_close(struct filter_node *fn)
1177 struct private_wmadec_data *pwd = fn->private_data;
1181 wmadec_cleanup(pwd);
1182 free(fn->private_data);
1183 fn->private_data = NULL;
1186 static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
1188 struct filter_node *fn = btr_context(btrn);
1189 struct private_wmadec_data *pwd = fn->private_data;
1191 return decoder_execute(cmd, pwd->ahi.sample_rate, pwd->ahi.channels,
1195 #define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
1197 static int wmadec_post_select(__a_unused struct sched *s, void *context)
1199 struct filter_node *fn = context;
1200 int ret, converted, out_size;
1201 struct private_wmadec_data *pwd = fn->private_data;
1202 struct btr_node *btrn = fn->btrn;
1208 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
1213 btr_merge(btrn, fn->min_iqs);
1214 len = btr_next_buffer(btrn, &in);
1215 ret = -E_WMADEC_EOF;
1216 if (len < fn->min_iqs)
1219 ret = wma_decode_init(in, len, &pwd);
1223 fn->min_iqs += 4096;
1226 fn->min_iqs = 2 * pwd->ahi.packet_size;
1227 fn->private_data = pwd;
1228 converted = pwd->ahi.header_len;
1231 fn->min_iqs = pwd->ahi.packet_size;
1232 if (fn->min_iqs > len)
1234 out_size = WMA_OUTPUT_BUFFER_SIZE;
1235 out = para_malloc(out_size);
1236 ret = wma_decode_superframe(pwd, out, &out_size,
1237 (uint8_t *)in + WMA_FRAME_SKIP, len - WMA_FRAME_SKIP);
1243 out = para_realloc(out, out_size);
1244 btr_add_output(out, out_size, btrn);
1247 converted += pwd->ahi.packet_size;
1249 btr_consume(btrn, converted);
1253 btr_remove_node(&fn->btrn);
1257 static void wmadec_open(struct filter_node *fn)
1259 fn->private_data = NULL;
1264 * The init function of the wma decoder.
1266 * \param f Its fields are filled in by the function.
1268 void wmadec_filter_init(struct filter *f)
1270 f->open = wmadec_open;
1271 f->close = wmadec_close;
1272 f->execute = wmadec_execute;
1273 f->pre_select = generic_filter_pre_select;
1274 f->post_select = wmadec_post_select;