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>
29 #include "buffer_tree.h"
31 #include "portable_io.h"
32 #include "bitstream.h"
39 #define BLOCK_MIN_BITS 7
40 #define BLOCK_MAX_BITS 11
41 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
43 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
45 /* XXX: find exact max size */
46 #define HIGH_BAND_MAX_SIZE 16
48 /* XXX: is it a suitable value ? */
49 #define MAX_CODED_SUPERFRAME_SIZE 16384
51 #define MAX_CHANNELS 2
53 #define NOISE_TAB_SIZE 8192
55 #define LSP_POW_BITS 7
57 struct private_wmadec_data {
58 /** Information contained in the audio file header. */
59 struct asf_header_info ahi;
60 struct getbit_context gb;
61 /** Whether perceptual noise is added. */
63 /** Depends on number of the bits per second and the frame length. */
65 /** Only used if ahi->use_exp_vlc is true. */
67 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
68 /** The index of the first coef in high band. */
69 int high_band_start[BLOCK_NB_SIZES];
70 /** Maximal number of coded coefficients. */
71 int coefs_end[BLOCK_NB_SIZES];
72 int exponent_high_sizes[BLOCK_NB_SIZES];
73 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
76 /* coded values in high bands */
77 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
78 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
80 /* there are two possible tables for spectral coefficients */
81 struct vlc coef_vlc[2];
82 uint16_t *run_table[2];
83 uint16_t *level_table[2];
84 /** Frame length in samples. */
86 /** log2 of frame_len. */
88 /** Number of block sizes, one if !ahi->use_variable_block_len. */
90 /* Whether to update block lengths from getbit context. */
91 bool reset_block_lengths;
92 /** log2 of current block length. */
94 /** log2 of next block length. */
95 int next_block_len_bits;
96 /** log2 of previous block length. */
97 int prev_block_len_bits;
98 /** Block length in samples. */
100 /** Current position in frame. */
102 /** True if channel is coded. */
103 uint8_t channel_coded[MAX_CHANNELS];
104 /** log2 ratio frame/exp. length. */
105 int exponents_bsize[MAX_CHANNELS];
107 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
108 float max_exponent[MAX_CHANNELS];
109 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
110 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
111 float output[BLOCK_MAX_SIZE * 2];
112 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
113 float *windows[BLOCK_NB_SIZES];
114 /** Output buffer for one frame and the last for IMDCT windowing. */
115 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
116 /** Last frame info. */
117 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
119 int last_superframe_len;
120 float noise_table[NOISE_TAB_SIZE];
122 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
123 /* lsp_to_curve tables */
124 float lsp_cos_table[BLOCK_MAX_SIZE];
125 float lsp_pow_e_table[256];
126 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
127 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
131 #define HGAINVLCBITS 9
134 /** \cond sine_winows */
136 #define SINE_WINDOW(x) static float sine_ ## x[x] __a_aligned(16)
145 static float *sine_windows[6] = {
146 sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
148 /** \endcond sine_windows */
150 /* Generate a sine window. */
151 static void sine_window_init(float *window, int n)
155 for (i = 0; i < n; i++)
156 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
159 static void init_coef_vlc(struct private_wmadec_data *pwd, int sidx, int didx)
161 const struct coef_vlc_table *src = coef_vlcs + sidx;
162 struct vlc *dst = pwd->coef_vlc + didx;
163 int i, l, j, k, level, n = src->n;
165 init_vlc(dst, VLCBITS, n, src->huffbits, src->huffcodes, 4);
166 pwd->run_table[didx] = para_malloc(n * sizeof(uint16_t));
167 pwd->level_table[didx] = para_malloc(n * sizeof(uint16_t));
172 l = src->levels[k++];
173 for (j = 0; j < l; j++) {
174 pwd->run_table[didx][i] = j;
175 pwd->level_table[didx][i] = level;
182 /* compute the scale factor band sizes for each MDCT block size */
183 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
186 struct asf_header_info *ahi = &pwd->ahi;
187 int a, b, pos, lpos, k, block_len, i, j, n;
188 const uint8_t *table;
190 for (k = 0; k < pwd->nb_block_sizes; k++) {
193 block_len = pwd->frame_len >> k;
195 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
197 if (ahi->sample_rate >= 44100)
198 table = exponent_band_44100[a];
199 else if (ahi->sample_rate >= 32000)
200 table = exponent_band_32000[a];
201 else if (ahi->sample_rate >= 22050)
202 table = exponent_band_22050[a];
206 for (i = 0; i < n; i++)
207 pwd->exponent_bands[k][i] = table[i];
212 for (i = 0; i < 25; i++) {
213 a = wma_critical_freqs[i];
214 b = ahi->sample_rate;
215 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
220 pwd->exponent_bands[k][j++] = pos - lpos;
221 if (pos >= block_len)
228 /* max number of coefs */
229 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
230 /* high freq computation */
231 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
232 / ahi->sample_rate + 0.5);
236 for (i = 0; i < n; i++) {
239 pos += pwd->exponent_bands[k][i];
241 if (start < pwd->high_band_start[k])
242 start = pwd->high_band_start[k];
243 if (end > pwd->coefs_end[k])
244 end = pwd->coefs_end[k];
246 pwd->exponent_high_bands[k][j++] = end - start;
248 pwd->exponent_high_sizes[k] = j;
252 static int wma_init(struct private_wmadec_data *pwd)
255 float bps1, high_freq;
259 struct asf_header_info *ahi = &pwd->ahi;
260 int flags2 = ahi->flags2;
262 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
263 || ahi->channels <= 0 || ahi->channels > 8
264 || ahi->bit_rate <= 0)
265 return -E_WMA_BAD_PARAMS;
267 /* compute MDCT block size */
268 if (ahi->sample_rate <= 16000)
269 pwd->frame_len_bits = 9;
270 else if (ahi->sample_rate <= 22050)
271 pwd->frame_len_bits = 10;
273 pwd->frame_len_bits = 11;
274 pwd->frame_len = 1 << pwd->frame_len_bits;
275 if (pwd->ahi.use_variable_block_len) {
277 nb = ((flags2 >> 3) & 3) + 1;
278 if ((ahi->bit_rate / ahi->channels) >= 32000)
280 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
283 pwd->nb_block_sizes = nb + 1;
285 pwd->nb_block_sizes = 1;
287 /* init rate dependent parameters */
288 pwd->use_noise_coding = 1;
289 high_freq = ahi->sample_rate * 0.5;
291 /* wma2 rates are normalized */
292 sample_rate1 = ahi->sample_rate;
293 if (sample_rate1 >= 44100)
294 sample_rate1 = 44100;
295 else if (sample_rate1 >= 22050)
296 sample_rate1 = 22050;
297 else if (sample_rate1 >= 16000)
298 sample_rate1 = 16000;
299 else if (sample_rate1 >= 11025)
300 sample_rate1 = 11025;
301 else if (sample_rate1 >= 8000)
304 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
305 pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
307 * Compute high frequency value and choose if noise coding should be
311 if (ahi->channels == 2)
313 if (sample_rate1 == 44100) {
315 pwd->use_noise_coding = 0;
317 high_freq = high_freq * 0.4;
318 } else if (sample_rate1 == 22050) {
320 pwd->use_noise_coding = 0;
321 else if (bps1 >= 0.72)
322 high_freq = high_freq * 0.7;
324 high_freq = high_freq * 0.6;
325 } else if (sample_rate1 == 16000) {
327 high_freq = high_freq * 0.5;
329 high_freq = high_freq * 0.3;
330 } else if (sample_rate1 == 11025)
331 high_freq = high_freq * 0.7;
332 else if (sample_rate1 == 8000) {
334 high_freq = high_freq * 0.5;
336 pwd->use_noise_coding = 0;
338 high_freq = high_freq * 0.65;
341 high_freq = high_freq * 0.75;
343 high_freq = high_freq * 0.6;
345 high_freq = high_freq * 0.5;
347 PARA_INFO_LOG("channels=%u sample_rate=%u "
348 "bitrate=%u block_align=%d\n",
349 ahi->channels, ahi->sample_rate,
350 ahi->bit_rate, ahi->block_align);
351 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
352 "high_freq=%f bitoffset=%d\n",
353 pwd->frame_len, bps, bps1,
354 high_freq, pwd->byte_offset_bits);
355 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
356 pwd->use_noise_coding, pwd->ahi.use_exp_vlc, pwd->nb_block_sizes);
358 compute_scale_factor_band_sizes(pwd, high_freq);
359 /* init MDCT windows : simple sinus window */
360 for (i = 0; i < pwd->nb_block_sizes; i++) {
362 n = 1 << (pwd->frame_len_bits - i);
363 sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
364 pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
367 pwd->reset_block_lengths = true;
369 if (pwd->use_noise_coding) {
370 /* init the noise generator */
371 if (pwd->ahi.use_exp_vlc)
372 pwd->noise_mult = 0.02;
374 pwd->noise_mult = 0.04;
380 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
381 for (i = 0; i < NOISE_TAB_SIZE; i++) {
382 seed = seed * 314159 + 1;
383 pwd->noise_table[i] = (float) ((int) seed) * norm;
388 /* choose the VLC tables for the coefficients */
390 if (ahi->sample_rate >= 32000) {
393 else if (bps1 < 1.16)
396 init_coef_vlc(pwd, coef_vlc_table, 0);
397 init_coef_vlc(pwd, coef_vlc_table + 1, 1);
401 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd)
406 wdel = M_PI / pwd->frame_len;
407 for (i = 0; i < pwd->frame_len; i++)
408 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
410 /* tables for x^-0.25 computation */
411 for (i = 0; i < 256; i++) {
413 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
416 /* These two tables are needed to avoid two operations in pow_m1_4. */
418 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
419 m = (1 << LSP_POW_BITS) + i;
420 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
422 pwd->lsp_pow_m_table1[i] = 2 * a - b;
423 pwd->lsp_pow_m_table2[i] = b - a;
428 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
430 struct private_wmadec_data *pwd;
433 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
434 pwd = para_calloc(sizeof(*pwd));
435 ret = read_asf_header(initial_buf, len, &pwd->ahi);
445 for (i = 0; i < pwd->nb_block_sizes; i++) {
446 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
450 if (pwd->use_noise_coding) {
451 PARA_INFO_LOG("using noise coding\n");
452 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
453 sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
454 wma_hgain_huffcodes, 2);
457 if (pwd->ahi.use_exp_vlc) {
458 PARA_INFO_LOG("using exp_vlc\n");
459 init_vlc(&pwd->exp_vlc, EXPVLCBITS, sizeof(wma_scale_huffbits),
460 wma_scale_huffbits, wma_scale_huffcodes, 4);
462 PARA_INFO_LOG("using curve\n");
463 wma_lsp_to_curve_init(pwd);
466 return pwd->ahi.header_len;
470 * compute x^-0.25 with an exponent and mantissa table. We use linear
471 * interpolation to reduce the mantissa table size at a small speed
472 * expense (linear interpolation approximately doubles the number of
473 * bits of precision).
475 static inline float pow_m1_4(struct private_wmadec_data *pwd, float x)
486 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
487 /* build interpolation scale: 1 <= t < 2. */
488 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
489 a = pwd->lsp_pow_m_table1[m];
490 b = pwd->lsp_pow_m_table2[m];
491 return pwd->lsp_pow_e_table[e] * (a + b * t.f);
494 static void wma_lsp_to_curve(struct private_wmadec_data *pwd,
495 float *out, float *val_max_ptr, int n, float *lsp)
498 float p, q, w, v, val_max;
501 for (i = 0; i < n; i++) {
504 w = pwd->lsp_cos_table[i];
505 for (j = 1; j < NB_LSP_COEFS; j += 2) {
512 v = pow_m1_4(pwd, v);
517 *val_max_ptr = val_max;
520 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
521 static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
523 float lsp_coefs[NB_LSP_COEFS];
526 for (i = 0; i < NB_LSP_COEFS; i++) {
527 if (i == 0 || i >= 8)
528 val = get_bits(&pwd->gb, 3);
530 val = get_bits(&pwd->gb, 4);
531 lsp_coefs[i] = wma_lsp_codebook[i][val];
534 wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
535 pwd->block_len, lsp_coefs);
538 /* Decode exponents coded with VLC codes. */
539 static int decode_exp_vlc(struct private_wmadec_data *pwd, int ch)
541 int last_exp, n, code;
542 const uint16_t *ptr, *band_ptr;
543 float v, *q, max_scale, *q_end;
545 band_ptr = pwd->exponent_bands[pwd->frame_len_bits - pwd->block_len_bits];
547 q = pwd->exponents[ch];
548 q_end = q + pwd->block_len;
553 code = get_vlc(&pwd->gb, &pwd->exp_vlc);
556 /* NOTE: this offset is the same as MPEG4 AAC ! */
557 last_exp += code - 60;
558 /* XXX: use a table */
559 v = pow(10, last_exp * (1.0 / 16.0));
567 pwd->max_exponent[ch] = max_scale;
571 /* compute src0 * src1 + src2 */
572 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
573 const float *src2, int len)
577 for (i = 0; i < len; i++)
578 dst[i] = src0[i] * src1[i] + src2[i];
581 static inline void vector_mult_reverse(float *dst, const float *src0,
582 const float *src1, int len)
587 for (i = 0; i < len; i++)
588 dst[i] = src0[i] * src1[-i];
592 * Apply MDCT window and add into output.
594 * We ensure that when the windows overlap their squared sum
595 * is always 1 (MDCT reconstruction rule).
597 static void wma_window(struct private_wmadec_data *pwd, float *out)
599 float *in = pwd->output;
600 int block_len, bsize, n;
603 if (pwd->block_len_bits <= pwd->prev_block_len_bits) {
604 block_len = pwd->block_len;
605 bsize = pwd->frame_len_bits - pwd->block_len_bits;
606 vector_mult_add(out, in, pwd->windows[bsize], out, block_len);
608 block_len = 1 << pwd->prev_block_len_bits;
609 n = (pwd->block_len - block_len) / 2;
610 bsize = pwd->frame_len_bits - pwd->prev_block_len_bits;
611 vector_mult_add(out + n, in + n, pwd->windows[bsize], out + n,
613 memcpy(out + n + block_len, in + n + block_len,
616 out += pwd->block_len;
617 in += pwd->block_len;
619 if (pwd->block_len_bits <= pwd->next_block_len_bits) {
620 block_len = pwd->block_len;
621 bsize = pwd->frame_len_bits - pwd->block_len_bits;
622 vector_mult_reverse(out, in, pwd->windows[bsize], block_len);
624 block_len = 1 << pwd->next_block_len_bits;
625 n = (pwd->block_len - block_len) / 2;
626 bsize = pwd->frame_len_bits - pwd->next_block_len_bits;
627 memcpy(out, in, n * sizeof(float));
628 vector_mult_reverse(out + n, in + n, pwd->windows[bsize],
630 memset(out + n + block_len, 0, n * sizeof(float));
634 static int wma_total_gain_to_bits(int total_gain)
638 else if (total_gain < 32)
640 else if (total_gain < 40)
642 else if (total_gain < 45)
648 static int compute_high_band_values(struct private_wmadec_data *pwd,
649 int bsize, int nb_coefs[MAX_CHANNELS])
653 if (!pwd->use_noise_coding)
655 for (ch = 0; ch < pwd->ahi.channels; ch++) {
657 if (!pwd->channel_coded[ch])
659 m = pwd->exponent_high_sizes[bsize];
660 for (i = 0; i < m; i++) {
661 a = get_bit(&pwd->gb);
662 pwd->high_band_coded[ch][i] = a;
665 nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
668 for (ch = 0; ch < pwd->ahi.channels; ch++) {
670 if (!pwd->channel_coded[ch])
672 n = pwd->exponent_high_sizes[bsize];
673 val = (int)0x80000000;
674 for (i = 0; i < n; i++) {
675 if (!pwd->high_band_coded[ch][i])
677 if (val == (int)0x80000000)
678 val = get_bits(&pwd->gb, 7) - 19;
680 int code = get_vlc(&pwd->gb, &pwd->hgain_vlc);
685 pwd->high_band_values[ch][i] = val;
691 static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
692 int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
695 float mdct_norm = 1.0 / (pwd->block_len / 2);
697 for (ch = 0; ch < pwd->ahi.channels; ch++) {
699 float *coefs, *exponents, mult, mult1, noise;
700 int i, j, n, n1, last_high_band, esize;
701 float exp_power[HIGH_BAND_MAX_SIZE];
703 if (!pwd->channel_coded[ch])
705 coefs1 = pwd->coefs1[ch];
706 exponents = pwd->exponents[ch];
707 esize = pwd->exponents_bsize[ch];
708 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
710 coefs = pwd->coefs[ch];
711 if (!pwd->use_noise_coding) {
712 /* XXX: optimize more */
714 for (i = 0; i < n; i++)
715 *coefs++ = coefs1[i] *
716 exponents[i << bsize >> esize] * mult;
717 n = pwd->block_len - pwd->coefs_end[bsize];
718 for (i = 0; i < n; i++)
722 n1 = pwd->exponent_high_sizes[bsize];
723 /* compute power of high bands */
724 exponents = pwd->exponents[ch] +
725 (pwd->high_band_start[bsize] << bsize);
726 last_high_band = 0; /* avoid warning */
727 for (j = 0; j < n1; j++) {
728 n = pwd->exponent_high_bands[
729 pwd->frame_len_bits - pwd->block_len_bits][j];
730 if (pwd->high_band_coded[ch][j]) {
733 for (i = 0; i < n; i++) {
734 val = exponents[i << bsize >> esize];
737 exp_power[j] = e2 / n;
740 exponents += n << bsize;
742 /* main freqs and high freqs */
743 exponents = pwd->exponents[ch];
744 for (j = -1; j < n1; j++) {
746 n = pwd->high_band_start[bsize];
748 n = pwd->exponent_high_bands[pwd->frame_len_bits
749 - pwd->block_len_bits][j];
750 if (j >= 0 && pwd->high_band_coded[ch][j]) {
751 /* use noise with specified power */
752 mult1 = sqrt(exp_power[j]
753 / exp_power[last_high_band]);
754 /* XXX: use a table */
755 mult1 *= pow(10, pwd->high_band_values[ch][j] * 0.05);
756 mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
758 for (i = 0; i < n; i++) {
759 noise = pwd->noise_table[pwd->noise_index];
760 pwd->noise_index = (pwd->noise_index + 1)
761 & (NOISE_TAB_SIZE - 1);
762 *coefs++ = noise * exponents[
763 i << bsize >> esize] * mult1;
765 exponents += n << bsize;
767 /* coded values + small noise */
768 for (i = 0; i < n; i++) {
769 noise = pwd->noise_table[pwd->noise_index];
770 pwd->noise_index = (pwd->noise_index + 1)
771 & (NOISE_TAB_SIZE - 1);
772 *coefs++ = ((*coefs1++) + noise) *
773 exponents[i << bsize >> esize]
776 exponents += n << bsize;
779 /* very high freqs: noise */
780 n = pwd->block_len - pwd->coefs_end[bsize];
781 mult1 = mult * exponents[(-(1 << bsize)) >> esize];
782 for (i = 0; i < n; i++) {
783 *coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
784 pwd->noise_index = (pwd->noise_index + 1)
785 & (NOISE_TAB_SIZE - 1);
791 * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
794 static int wma_decode_block(struct private_wmadec_data *pwd)
796 int ret, n, v, ch, code, bsize;
797 int coef_nb_bits, total_gain;
798 int nb_coefs[MAX_CHANNELS];
799 bool ms_stereo = false; /* mid/side stereo mode */
801 /* compute current block length */
802 if (pwd->ahi.use_variable_block_len) {
803 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
805 if (pwd->reset_block_lengths) {
806 pwd->reset_block_lengths = false;
807 v = get_bits(&pwd->gb, n);
808 if (v >= pwd->nb_block_sizes)
809 return -E_WMA_BLOCK_SIZE;
810 pwd->prev_block_len_bits = pwd->frame_len_bits - v;
811 v = get_bits(&pwd->gb, n);
812 if (v >= pwd->nb_block_sizes)
813 return -E_WMA_BLOCK_SIZE;
814 pwd->block_len_bits = pwd->frame_len_bits - v;
816 /* update block lengths */
817 pwd->prev_block_len_bits = pwd->block_len_bits;
818 pwd->block_len_bits = pwd->next_block_len_bits;
820 v = get_bits(&pwd->gb, n);
821 if (v >= pwd->nb_block_sizes)
822 return -E_WMA_BLOCK_SIZE;
823 pwd->next_block_len_bits = pwd->frame_len_bits - v;
825 /* fixed block len */
826 pwd->next_block_len_bits = pwd->frame_len_bits;
827 pwd->prev_block_len_bits = pwd->frame_len_bits;
828 pwd->block_len_bits = pwd->frame_len_bits;
831 /* now check if the block length is coherent with the frame length */
832 pwd->block_len = 1 << pwd->block_len_bits;
833 if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
834 return -E_INCOHERENT_BLOCK_LEN;
836 if (pwd->ahi.channels == 2)
837 ms_stereo = get_bit(&pwd->gb);
839 for (ch = 0; ch < pwd->ahi.channels; ch++) {
840 int a = get_bit(&pwd->gb);
841 pwd->channel_coded[ch] = a;
845 bsize = pwd->frame_len_bits - pwd->block_len_bits;
847 /* if no channel coded, no need to go further */
848 /* XXX: fix potential framing problems */
853 * Read total gain and extract corresponding number of bits for coef
858 int a = get_bits(&pwd->gb, 7);
864 coef_nb_bits = wma_total_gain_to_bits(total_gain);
866 /* compute number of coefficients */
867 n = pwd->coefs_end[bsize];
868 for (ch = 0; ch < pwd->ahi.channels; ch++)
871 ret = compute_high_band_values(pwd, bsize, nb_coefs);
875 /* exponents can be reused in short blocks. */
876 if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
877 for (ch = 0; ch < pwd->ahi.channels; ch++) {
878 if (pwd->channel_coded[ch]) {
879 if (pwd->ahi.use_exp_vlc) {
880 ret = decode_exp_vlc(pwd, ch);
884 decode_exp_lsp(pwd, ch);
885 pwd->exponents_bsize[ch] = bsize;
890 /* parse spectral coefficients : just RLE encoding */
891 for (ch = 0; ch < pwd->ahi.channels; ch++) {
892 struct vlc *coef_vlc;
893 int level, run, tindex;
895 const uint16_t *level_table, *run_table;
897 if (!pwd->channel_coded[ch])
900 * special VLC tables are used for ms stereo because there is
901 * potentially less energy there
903 tindex = ch == 1 && ms_stereo;
904 coef_vlc = &pwd->coef_vlc[tindex];
905 run_table = pwd->run_table[tindex];
906 level_table = pwd->level_table[tindex];
908 ptr = &pwd->coefs1[ch][0];
909 eptr = ptr + nb_coefs[ch];
910 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
912 code = get_vlc(&pwd->gb, coef_vlc);
915 if (code == 1) /* EOB */
917 if (code == 0) { /* escape */
918 level = get_bits(&pwd->gb, coef_nb_bits);
919 /* reading block_len_bits would be better */
920 run = get_bits(&pwd->gb, pwd->frame_len_bits);
921 } else { /* normal code */
922 run = run_table[code];
923 level = level_table[code];
925 if (!get_bit(&pwd->gb))
929 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
933 if (ptr >= eptr) /* EOB can be omitted */
937 compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
938 if (ms_stereo && pwd->channel_coded[1]) {
942 * Nominal case for ms stereo: we do it before mdct.
944 * No need to optimize this case because it should almost never
947 if (!pwd->channel_coded[0]) {
948 PARA_NOTICE_LOG("rare ms-stereo\n");
949 memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
950 pwd->channel_coded[0] = 1;
952 for (i = 0; i < pwd->block_len; i++) {
953 a = pwd->coefs[0][i];
954 b = pwd->coefs[1][i];
955 pwd->coefs[0][i] = a + b;
956 pwd->coefs[1][i] = a - b;
960 for (ch = 0; ch < pwd->ahi.channels; ch++) {
963 n4 = pwd->block_len / 2;
964 if (pwd->channel_coded[ch])
965 imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
966 else if (!(ms_stereo && ch == 1))
967 memset(pwd->output, 0, sizeof(pwd->output));
969 /* multiply by the window and add in the frame */
970 idx = (pwd->frame_len / 2) + pwd->block_pos - n4;
971 wma_window(pwd, &pwd->frame_out[ch][idx]);
974 /* update block number */
975 pwd->block_pos += pwd->block_len;
976 if (pwd->block_pos >= pwd->frame_len)
983 * Clip a signed integer value into the -32768,32767 range.
985 * \param a The value to clip.
987 * \return The clipped value.
989 static inline int16_t av_clip_int16(int a)
991 if ((a + 32768) & ~65535)
992 return (a >> 31) ^ 32767;
997 /* Decode a frame of frame_len samples. */
998 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1004 /* read each block */
1007 ret = wma_decode_block(pwd);
1014 /* convert frame to integer */
1015 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1017 iptr = pwd->frame_out[ch];
1019 for (i = 0; i < pwd->frame_len; i++) {
1020 *ptr = av_clip_int16(lrintf(*iptr++));
1021 ptr += pwd->ahi.channels;
1023 /* prepare for next block */
1024 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1025 pwd->frame_len * sizeof(float));
1030 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *out,
1031 int *out_size, const uint8_t *in)
1033 int ret, in_size = pwd->ahi.packet_size - WMA_FRAME_SKIP;
1034 int16_t *samples = out;
1036 init_get_bits(&pwd->gb, in, in_size);
1037 if (pwd->ahi.use_bit_reservoir) {
1038 int i, nb_frames, bit_offset, pos, len;
1041 /* read super frame header */
1042 skip_bits(&pwd->gb, 4); /* super frame index */
1043 nb_frames = get_bits(&pwd->gb, 4) - 1;
1044 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1045 ret = -E_WMA_OUTPUT_SPACE;
1046 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1047 * sizeof(int16_t) > *out_size)
1050 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1052 if (pwd->last_superframe_len > 0) {
1053 /* add bit_offset bits to last frame */
1054 ret = -E_WMA_BAD_SUPERFRAME;
1055 if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1056 MAX_CODED_SUPERFRAME_SIZE)
1058 q = pwd->last_superframe + pwd->last_superframe_len;
1061 *q++ = get_bits(&pwd->gb, 8);
1065 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1067 /* XXX: bit_offset bits into last frame */
1068 init_get_bits(&pwd->gb, pwd->last_superframe,
1069 MAX_CODED_SUPERFRAME_SIZE);
1070 /* skip unused bits */
1071 if (pwd->last_bitoffset > 0)
1072 skip_bits(&pwd->gb, pwd->last_bitoffset);
1074 * This frame is stored in the last superframe and in
1077 ret = wma_decode_frame(pwd, samples);
1080 samples += pwd->ahi.channels * pwd->frame_len;
1083 /* read each frame starting from bit_offset */
1084 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1085 init_get_bits(&pwd->gb, in + (pos >> 3),
1086 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1089 skip_bits(&pwd->gb, len);
1091 pwd->reset_block_lengths = true;
1092 for (i = 0; i < nb_frames; i++) {
1093 ret = wma_decode_frame(pwd, samples);
1096 samples += pwd->ahi.channels * pwd->frame_len;
1099 /* we copy the end of the frame in the last frame buffer */
1100 pos = get_bits_count(&pwd->gb) +
1101 ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1102 pwd->last_bitoffset = pos & 7;
1104 len = in_size - pos;
1105 ret = -E_WMA_BAD_SUPERFRAME;
1106 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1108 pwd->last_superframe_len = len;
1109 memcpy(pwd->last_superframe, in + pos, len);
1111 PARA_DEBUG_LOG("not using bit reservoir\n");
1112 ret = -E_WMA_OUTPUT_SPACE;
1113 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *out_size)
1115 /* single frame decode */
1116 ret = wma_decode_frame(pwd, samples);
1119 samples += pwd->ahi.channels * pwd->frame_len;
1121 PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
1122 pwd->frame_len, pwd->block_len,
1123 (int)((int8_t *)samples - (int8_t *)out), pwd->ahi.block_align);
1124 *out_size = (int8_t *)samples - (int8_t *)out;
1125 return pwd->ahi.block_align;
1127 /* reset the bit reservoir on errors */
1128 pwd->last_superframe_len = 0;
1132 static void wmadec_close(struct filter_node *fn)
1134 struct private_wmadec_data *pwd = fn->private_data;
1139 for (i = 0; i < pwd->nb_block_sizes; i++)
1140 imdct_end(pwd->mdct_ctx[i]);
1141 if (pwd->ahi.use_exp_vlc)
1142 free_vlc(&pwd->exp_vlc);
1143 if (pwd->use_noise_coding)
1144 free_vlc(&pwd->hgain_vlc);
1145 for (i = 0; i < 2; i++) {
1146 free_vlc(&pwd->coef_vlc[i]);
1147 free(pwd->run_table[i]);
1148 free(pwd->level_table[i]);
1150 free(fn->private_data);
1151 fn->private_data = NULL;
1154 static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
1156 struct filter_node *fn = btr_context(btrn);
1157 struct private_wmadec_data *pwd = fn->private_data;
1159 return decoder_execute(cmd, pwd->ahi.sample_rate, pwd->ahi.channels,
1163 #define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
1165 static int wmadec_post_select(__a_unused struct sched *s, void *context)
1167 struct filter_node *fn = context;
1168 int ret, converted, out_size;
1169 struct private_wmadec_data *pwd = fn->private_data;
1170 struct btr_node *btrn = fn->btrn;
1176 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
1181 btr_merge(btrn, fn->min_iqs);
1182 len = btr_next_buffer(btrn, &in);
1183 ret = -E_WMADEC_EOF;
1184 if (len < fn->min_iqs)
1187 ret = wma_decode_init(in, len, &pwd);
1191 fn->min_iqs += 4096;
1194 fn->min_iqs = 2 * pwd->ahi.packet_size;
1195 fn->private_data = pwd;
1196 converted = pwd->ahi.header_len;
1199 fn->min_iqs = pwd->ahi.packet_size;
1200 if (fn->min_iqs > len)
1202 out_size = WMA_OUTPUT_BUFFER_SIZE;
1203 out = para_malloc(out_size);
1204 ret = wma_decode_superframe(pwd, out, &out_size,
1205 (uint8_t *)in + WMA_FRAME_SKIP);
1211 out = para_realloc(out, out_size);
1212 btr_add_output(out, out_size, btrn);
1215 converted += pwd->ahi.packet_size;
1217 btr_consume(btrn, converted);
1221 btr_remove_node(&fn->btrn);
1225 static void wmadec_open(struct filter_node *fn)
1227 fn->private_data = NULL;
1231 const struct filter lsg_filter_cmd_com_wmadec_user_data = {
1232 .open = wmadec_open,
1233 .close = wmadec_close,
1234 .execute = wmadec_execute,
1235 .pre_select = generic_filter_pre_select,
1236 .post_select = wmadec_post_select,