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.
20 #include <sys/select.h>
27 #include "buffer_tree.h"
29 #include "portable_io.h"
30 #include "bitstream.h"
37 #define BLOCK_MIN_BITS 7
38 #define BLOCK_MAX_BITS 11
39 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
41 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
43 /* XXX: find exact max size */
44 #define HIGH_BAND_MAX_SIZE 16
46 /* XXX: is it a suitable value ? */
47 #define MAX_CODED_SUPERFRAME_SIZE 16384
49 #define MAX_CHANNELS 2
51 #define NOISE_TAB_SIZE 8192
53 #define LSP_POW_BITS 7
55 struct private_wmadec_data {
56 /** Information contained in the audio file header. */
57 struct asf_header_info ahi;
58 struct getbit_context gb;
59 /** Whether perceptual noise is added. */
61 /** Depends on number of the bits per second and the frame length. */
63 /** Only used if ahi->use_exp_vlc is true. */
65 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
66 /** The index of the first coef in high band. */
67 int high_band_start[BLOCK_NB_SIZES];
68 /** Maximal number of coded coefficients. */
69 int coefs_end[BLOCK_NB_SIZES];
70 int exponent_high_sizes[BLOCK_NB_SIZES];
71 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
74 /* coded values in high bands */
75 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
76 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
78 /* there are two possible tables for spectral coefficients */
79 struct vlc coef_vlc[2];
80 uint16_t *run_table[2];
81 uint16_t *level_table[2];
82 /** Frame length in samples. */
84 /** log2 of frame_len. */
86 /** Number of block sizes, one if !ahi->use_variable_block_len. */
88 /* Whether to update block lengths from getbit context. */
89 bool reset_block_lengths;
90 /** log2 of current block length. */
92 /** log2 of next block length. */
93 int next_block_len_bits;
94 /** log2 of previous block length. */
95 int prev_block_len_bits;
96 /** Block length in samples. */
98 /** Current position in frame. */
100 /** True if channel is coded. */
101 uint8_t channel_coded[MAX_CHANNELS];
102 /** log2 ratio frame/exp. length. */
103 int exponents_bsize[MAX_CHANNELS];
105 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
106 float max_exponent[MAX_CHANNELS];
107 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
108 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
109 float output[BLOCK_MAX_SIZE * 2];
110 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
111 float *windows[BLOCK_NB_SIZES];
112 /** Output buffer for one frame and the last for IMDCT windowing. */
113 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
114 /** Last frame info. */
115 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
117 int last_superframe_len;
118 float noise_table[NOISE_TAB_SIZE];
120 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
121 /* lsp_to_curve tables */
122 float lsp_cos_table[BLOCK_MAX_SIZE];
123 float lsp_pow_e_table[256];
124 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
125 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
129 #define HGAINVLCBITS 9
132 /** \cond sine_winows */
134 #define SINE_WINDOW(x) static float sine_ ## x[x] __a_aligned(16)
143 static float *sine_windows[6] = {
144 sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
146 /** \endcond sine_windows */
148 /* Generate a sine window. */
149 static void sine_window_init(float *window, int n)
153 for (i = 0; i < n; i++)
154 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
157 static void init_coef_vlc(struct private_wmadec_data *pwd, int sidx, int didx)
159 const struct coef_vlc_table *src = coef_vlcs + sidx;
160 struct vlc *dst = pwd->coef_vlc + didx;
161 int i, l, j, k, level, n = src->n;
163 init_vlc(dst, VLCBITS, n, src->huffbits, src->huffcodes, 4);
164 pwd->run_table[didx] = para_malloc(n * sizeof(uint16_t));
165 pwd->level_table[didx] = para_malloc(n * sizeof(uint16_t));
170 l = src->levels[k++];
171 for (j = 0; j < l; j++) {
172 pwd->run_table[didx][i] = j;
173 pwd->level_table[didx][i] = level;
180 /* compute the scale factor band sizes for each MDCT block size */
181 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
184 struct asf_header_info *ahi = &pwd->ahi;
185 int a, b, pos, lpos, k, block_len, i, j, n;
186 const uint8_t *table;
188 for (k = 0; k < pwd->nb_block_sizes; k++) {
191 block_len = pwd->frame_len >> k;
193 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
195 if (ahi->sample_rate >= 44100)
196 table = exponent_band_44100[a];
197 else if (ahi->sample_rate >= 32000)
198 table = exponent_band_32000[a];
199 else if (ahi->sample_rate >= 22050)
200 table = exponent_band_22050[a];
204 for (i = 0; i < n; i++)
205 pwd->exponent_bands[k][i] = table[i];
210 for (i = 0; i < 25; i++) {
211 a = wma_critical_freqs[i];
212 b = ahi->sample_rate;
213 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
218 pwd->exponent_bands[k][j++] = pos - lpos;
219 if (pos >= block_len)
226 /* max number of coefs */
227 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
228 /* high freq computation */
229 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
230 / ahi->sample_rate + 0.5);
234 for (i = 0; i < n; i++) {
237 pos += pwd->exponent_bands[k][i];
239 if (start < pwd->high_band_start[k])
240 start = pwd->high_band_start[k];
241 if (end > pwd->coefs_end[k])
242 end = pwd->coefs_end[k];
244 pwd->exponent_high_bands[k][j++] = end - start;
246 pwd->exponent_high_sizes[k] = j;
250 static int wma_init(struct private_wmadec_data *pwd)
253 float bps1, high_freq;
257 struct asf_header_info *ahi = &pwd->ahi;
258 int flags2 = ahi->flags2;
260 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
261 || ahi->channels <= 0 || ahi->channels > 8
262 || ahi->bit_rate <= 0)
263 return -E_WMA_BAD_PARAMS;
265 /* compute MDCT block size */
266 if (ahi->sample_rate <= 16000)
267 pwd->frame_len_bits = 9;
268 else if (ahi->sample_rate <= 22050)
269 pwd->frame_len_bits = 10;
271 pwd->frame_len_bits = 11;
272 pwd->frame_len = 1 << pwd->frame_len_bits;
273 if (pwd->ahi.use_variable_block_len) {
275 nb = ((flags2 >> 3) & 3) + 1;
276 if ((ahi->bit_rate / ahi->channels) >= 32000)
278 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
281 pwd->nb_block_sizes = nb + 1;
283 pwd->nb_block_sizes = 1;
285 /* init rate dependent parameters */
286 pwd->use_noise_coding = 1;
287 high_freq = ahi->sample_rate * 0.5;
289 /* wma2 rates are normalized */
290 sample_rate1 = ahi->sample_rate;
291 if (sample_rate1 >= 44100)
292 sample_rate1 = 44100;
293 else if (sample_rate1 >= 22050)
294 sample_rate1 = 22050;
295 else if (sample_rate1 >= 16000)
296 sample_rate1 = 16000;
297 else if (sample_rate1 >= 11025)
298 sample_rate1 = 11025;
299 else if (sample_rate1 >= 8000)
302 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
303 pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
305 * Compute high frequency value and choose if noise coding should be
309 if (ahi->channels == 2)
311 if (sample_rate1 == 44100) {
313 pwd->use_noise_coding = 0;
315 high_freq = high_freq * 0.4;
316 } else if (sample_rate1 == 22050) {
318 pwd->use_noise_coding = 0;
319 else if (bps1 >= 0.72)
320 high_freq = high_freq * 0.7;
322 high_freq = high_freq * 0.6;
323 } else if (sample_rate1 == 16000) {
325 high_freq = high_freq * 0.5;
327 high_freq = high_freq * 0.3;
328 } else if (sample_rate1 == 11025)
329 high_freq = high_freq * 0.7;
330 else if (sample_rate1 == 8000) {
332 high_freq = high_freq * 0.5;
334 pwd->use_noise_coding = 0;
336 high_freq = high_freq * 0.65;
339 high_freq = high_freq * 0.75;
341 high_freq = high_freq * 0.6;
343 high_freq = high_freq * 0.5;
345 PARA_INFO_LOG("channels=%u sample_rate=%u "
346 "bitrate=%u block_align=%d\n",
347 ahi->channels, ahi->sample_rate,
348 ahi->bit_rate, ahi->block_align);
349 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
350 "high_freq=%f bitoffset=%d\n",
351 pwd->frame_len, bps, bps1,
352 high_freq, pwd->byte_offset_bits);
353 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
354 pwd->use_noise_coding, pwd->ahi.use_exp_vlc, pwd->nb_block_sizes);
356 compute_scale_factor_band_sizes(pwd, high_freq);
357 /* init MDCT windows : simple sinus window */
358 for (i = 0; i < pwd->nb_block_sizes; i++) {
360 n = 1 << (pwd->frame_len_bits - i);
361 sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
362 pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
365 pwd->reset_block_lengths = true;
367 if (pwd->use_noise_coding) {
368 /* init the noise generator */
369 if (pwd->ahi.use_exp_vlc)
370 pwd->noise_mult = 0.02;
372 pwd->noise_mult = 0.04;
378 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
379 for (i = 0; i < NOISE_TAB_SIZE; i++) {
380 seed = seed * 314159 + 1;
381 pwd->noise_table[i] = (float) ((int) seed) * norm;
386 /* choose the VLC tables for the coefficients */
388 if (ahi->sample_rate >= 32000) {
391 else if (bps1 < 1.16)
394 init_coef_vlc(pwd, coef_vlc_table, 0);
395 init_coef_vlc(pwd, coef_vlc_table + 1, 1);
399 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd)
404 wdel = M_PI / pwd->frame_len;
405 for (i = 0; i < pwd->frame_len; i++)
406 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
408 /* tables for x^-0.25 computation */
409 for (i = 0; i < 256; i++) {
411 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
414 /* These two tables are needed to avoid two operations in pow_m1_4. */
416 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
417 m = (1 << LSP_POW_BITS) + i;
418 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
420 pwd->lsp_pow_m_table1[i] = 2 * a - b;
421 pwd->lsp_pow_m_table2[i] = b - a;
426 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
428 struct private_wmadec_data *pwd;
431 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
432 pwd = para_calloc(sizeof(*pwd));
433 ret = read_asf_header(initial_buf, len, &pwd->ahi);
443 for (i = 0; i < pwd->nb_block_sizes; i++) {
444 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
448 if (pwd->use_noise_coding) {
449 PARA_INFO_LOG("using noise coding\n");
450 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
451 sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
452 wma_hgain_huffcodes, 2);
455 if (pwd->ahi.use_exp_vlc) {
456 PARA_INFO_LOG("using exp_vlc\n");
457 init_vlc(&pwd->exp_vlc, EXPVLCBITS, sizeof(wma_scale_huffbits),
458 wma_scale_huffbits, wma_scale_huffcodes, 4);
460 PARA_INFO_LOG("using curve\n");
461 wma_lsp_to_curve_init(pwd);
464 return pwd->ahi.header_len;
468 * compute x^-0.25 with an exponent and mantissa table. We use linear
469 * interpolation to reduce the mantissa table size at a small speed
470 * expense (linear interpolation approximately doubles the number of
471 * bits of precision).
473 static inline float pow_m1_4(struct private_wmadec_data *pwd, float x)
484 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
485 /* build interpolation scale: 1 <= t < 2. */
486 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
487 a = pwd->lsp_pow_m_table1[m];
488 b = pwd->lsp_pow_m_table2[m];
489 return pwd->lsp_pow_e_table[e] * (a + b * t.f);
492 static void wma_lsp_to_curve(struct private_wmadec_data *pwd,
493 float *out, float *val_max_ptr, int n, float *lsp)
496 float p, q, w, v, val_max;
499 for (i = 0; i < n; i++) {
502 w = pwd->lsp_cos_table[i];
503 for (j = 1; j < NB_LSP_COEFS; j += 2) {
510 v = pow_m1_4(pwd, v);
515 *val_max_ptr = val_max;
518 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
519 static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
521 float lsp_coefs[NB_LSP_COEFS];
524 for (i = 0; i < NB_LSP_COEFS; i++) {
525 if (i == 0 || i >= 8)
526 val = get_bits(&pwd->gb, 3);
528 val = get_bits(&pwd->gb, 4);
529 lsp_coefs[i] = wma_lsp_codebook[i][val];
532 wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
533 pwd->block_len, lsp_coefs);
536 /* Decode exponents coded with VLC codes. */
537 static int decode_exp_vlc(struct private_wmadec_data *pwd, int ch)
539 int last_exp, n, code;
540 const uint16_t *ptr, *band_ptr;
541 float v, *q, max_scale, *q_end;
543 band_ptr = pwd->exponent_bands[pwd->frame_len_bits - pwd->block_len_bits];
545 q = pwd->exponents[ch];
546 q_end = q + pwd->block_len;
551 code = get_vlc(&pwd->gb, &pwd->exp_vlc);
554 /* NOTE: this offset is the same as MPEG4 AAC ! */
555 last_exp += code - 60;
556 /* XXX: use a table */
557 v = pow(10, last_exp * (1.0 / 16.0));
565 pwd->max_exponent[ch] = max_scale;
569 /* compute src0 * src1 + src2 */
570 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
571 const float *src2, int len)
575 for (i = 0; i < len; i++)
576 dst[i] = src0[i] * src1[i] + src2[i];
579 static inline void vector_mult_reverse(float *dst, const float *src0,
580 const float *src1, int len)
585 for (i = 0; i < len; i++)
586 dst[i] = src0[i] * src1[-i];
590 * Apply MDCT window and add into output.
592 * We ensure that when the windows overlap their squared sum
593 * is always 1 (MDCT reconstruction rule).
595 static void wma_window(struct private_wmadec_data *pwd, float *out)
597 float *in = pwd->output;
598 int block_len, bsize, n;
601 if (pwd->block_len_bits <= pwd->prev_block_len_bits) {
602 block_len = pwd->block_len;
603 bsize = pwd->frame_len_bits - pwd->block_len_bits;
604 vector_mult_add(out, in, pwd->windows[bsize], out, block_len);
606 block_len = 1 << pwd->prev_block_len_bits;
607 n = (pwd->block_len - block_len) / 2;
608 bsize = pwd->frame_len_bits - pwd->prev_block_len_bits;
609 vector_mult_add(out + n, in + n, pwd->windows[bsize], out + n,
611 memcpy(out + n + block_len, in + n + block_len,
614 out += pwd->block_len;
615 in += pwd->block_len;
617 if (pwd->block_len_bits <= pwd->next_block_len_bits) {
618 block_len = pwd->block_len;
619 bsize = pwd->frame_len_bits - pwd->block_len_bits;
620 vector_mult_reverse(out, in, pwd->windows[bsize], block_len);
622 block_len = 1 << pwd->next_block_len_bits;
623 n = (pwd->block_len - block_len) / 2;
624 bsize = pwd->frame_len_bits - pwd->next_block_len_bits;
625 memcpy(out, in, n * sizeof(float));
626 vector_mult_reverse(out + n, in + n, pwd->windows[bsize],
628 memset(out + n + block_len, 0, n * sizeof(float));
632 static int wma_total_gain_to_bits(int total_gain)
636 else if (total_gain < 32)
638 else if (total_gain < 40)
640 else if (total_gain < 45)
646 static int compute_high_band_values(struct private_wmadec_data *pwd,
647 int bsize, int nb_coefs[MAX_CHANNELS])
651 if (!pwd->use_noise_coding)
653 for (ch = 0; ch < pwd->ahi.channels; ch++) {
655 if (!pwd->channel_coded[ch])
657 m = pwd->exponent_high_sizes[bsize];
658 for (i = 0; i < m; i++) {
659 a = get_bit(&pwd->gb);
660 pwd->high_band_coded[ch][i] = a;
663 nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
666 for (ch = 0; ch < pwd->ahi.channels; ch++) {
668 if (!pwd->channel_coded[ch])
670 n = pwd->exponent_high_sizes[bsize];
671 val = (int)0x80000000;
672 for (i = 0; i < n; i++) {
673 if (!pwd->high_band_coded[ch][i])
675 if (val == (int)0x80000000)
676 val = get_bits(&pwd->gb, 7) - 19;
678 int code = get_vlc(&pwd->gb, &pwd->hgain_vlc);
683 pwd->high_band_values[ch][i] = val;
689 static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
690 int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
693 float mdct_norm = 1.0 / (pwd->block_len / 2);
695 for (ch = 0; ch < pwd->ahi.channels; ch++) {
697 float *coefs, *exponents, mult, mult1, noise;
698 int i, j, n, n1, last_high_band, esize;
699 float exp_power[HIGH_BAND_MAX_SIZE];
701 if (!pwd->channel_coded[ch])
703 coefs1 = pwd->coefs1[ch];
704 exponents = pwd->exponents[ch];
705 esize = pwd->exponents_bsize[ch];
706 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
708 coefs = pwd->coefs[ch];
709 if (!pwd->use_noise_coding) {
710 /* XXX: optimize more */
712 for (i = 0; i < n; i++)
713 *coefs++ = coefs1[i] *
714 exponents[i << bsize >> esize] * mult;
715 n = pwd->block_len - pwd->coefs_end[bsize];
716 for (i = 0; i < n; i++)
720 n1 = pwd->exponent_high_sizes[bsize];
721 /* compute power of high bands */
722 exponents = pwd->exponents[ch] +
723 (pwd->high_band_start[bsize] << bsize);
724 last_high_band = 0; /* avoid warning */
725 for (j = 0; j < n1; j++) {
726 n = pwd->exponent_high_bands[
727 pwd->frame_len_bits - pwd->block_len_bits][j];
728 if (pwd->high_band_coded[ch][j]) {
731 for (i = 0; i < n; i++) {
732 val = exponents[i << bsize >> esize];
735 exp_power[j] = e2 / n;
738 exponents += n << bsize;
740 /* main freqs and high freqs */
741 exponents = pwd->exponents[ch];
742 for (j = -1; j < n1; j++) {
744 n = pwd->high_band_start[bsize];
746 n = pwd->exponent_high_bands[pwd->frame_len_bits
747 - pwd->block_len_bits][j];
748 if (j >= 0 && pwd->high_band_coded[ch][j]) {
749 /* use noise with specified power */
750 mult1 = sqrt(exp_power[j]
751 / exp_power[last_high_band]);
752 /* XXX: use a table */
753 mult1 *= pow(10, pwd->high_band_values[ch][j] * 0.05);
754 mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
756 for (i = 0; i < n; i++) {
757 noise = pwd->noise_table[pwd->noise_index];
758 pwd->noise_index = (pwd->noise_index + 1)
759 & (NOISE_TAB_SIZE - 1);
760 *coefs++ = noise * exponents[
761 i << bsize >> esize] * mult1;
763 exponents += n << bsize;
765 /* coded values + small noise */
766 for (i = 0; i < n; i++) {
767 noise = pwd->noise_table[pwd->noise_index];
768 pwd->noise_index = (pwd->noise_index + 1)
769 & (NOISE_TAB_SIZE - 1);
770 *coefs++ = ((*coefs1++) + noise) *
771 exponents[i << bsize >> esize]
774 exponents += n << bsize;
777 /* very high freqs: noise */
778 n = pwd->block_len - pwd->coefs_end[bsize];
779 mult1 = mult * exponents[(-(1 << bsize)) >> esize];
780 for (i = 0; i < n; i++) {
781 *coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
782 pwd->noise_index = (pwd->noise_index + 1)
783 & (NOISE_TAB_SIZE - 1);
789 * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
792 static int wma_decode_block(struct private_wmadec_data *pwd)
794 int ret, n, v, ch, code, bsize;
795 int coef_nb_bits, total_gain;
796 int nb_coefs[MAX_CHANNELS];
797 bool ms_stereo = false; /* mid/side stereo mode */
799 /* compute current block length */
800 if (pwd->ahi.use_variable_block_len) {
801 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
803 if (pwd->reset_block_lengths) {
804 pwd->reset_block_lengths = false;
805 v = get_bits(&pwd->gb, n);
806 if (v >= pwd->nb_block_sizes)
807 return -E_WMA_BLOCK_SIZE;
808 pwd->prev_block_len_bits = pwd->frame_len_bits - v;
809 v = get_bits(&pwd->gb, n);
810 if (v >= pwd->nb_block_sizes)
811 return -E_WMA_BLOCK_SIZE;
812 pwd->block_len_bits = pwd->frame_len_bits - v;
814 /* update block lengths */
815 pwd->prev_block_len_bits = pwd->block_len_bits;
816 pwd->block_len_bits = pwd->next_block_len_bits;
818 v = get_bits(&pwd->gb, n);
819 if (v >= pwd->nb_block_sizes)
820 return -E_WMA_BLOCK_SIZE;
821 pwd->next_block_len_bits = pwd->frame_len_bits - v;
823 /* fixed block len */
824 pwd->next_block_len_bits = pwd->frame_len_bits;
825 pwd->prev_block_len_bits = pwd->frame_len_bits;
826 pwd->block_len_bits = pwd->frame_len_bits;
829 /* now check if the block length is coherent with the frame length */
830 pwd->block_len = 1 << pwd->block_len_bits;
831 if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
832 return -E_INCOHERENT_BLOCK_LEN;
834 if (pwd->ahi.channels == 2)
835 ms_stereo = get_bit(&pwd->gb);
837 for (ch = 0; ch < pwd->ahi.channels; ch++) {
838 int a = get_bit(&pwd->gb);
839 pwd->channel_coded[ch] = a;
843 bsize = pwd->frame_len_bits - pwd->block_len_bits;
845 /* if no channel coded, no need to go further */
846 /* XXX: fix potential framing problems */
851 * Read total gain and extract corresponding number of bits for coef
856 int a = get_bits(&pwd->gb, 7);
862 coef_nb_bits = wma_total_gain_to_bits(total_gain);
864 /* compute number of coefficients */
865 n = pwd->coefs_end[bsize];
866 for (ch = 0; ch < pwd->ahi.channels; ch++)
869 ret = compute_high_band_values(pwd, bsize, nb_coefs);
873 /* exponents can be reused in short blocks. */
874 if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
875 for (ch = 0; ch < pwd->ahi.channels; ch++) {
876 if (pwd->channel_coded[ch]) {
877 if (pwd->ahi.use_exp_vlc) {
878 ret = decode_exp_vlc(pwd, ch);
882 decode_exp_lsp(pwd, ch);
883 pwd->exponents_bsize[ch] = bsize;
888 /* parse spectral coefficients : just RLE encoding */
889 for (ch = 0; ch < pwd->ahi.channels; ch++) {
890 struct vlc *coef_vlc;
891 int level, run, tindex;
893 const uint16_t *level_table, *run_table;
895 if (!pwd->channel_coded[ch])
898 * special VLC tables are used for ms stereo because there is
899 * potentially less energy there
901 tindex = ch == 1 && ms_stereo;
902 coef_vlc = &pwd->coef_vlc[tindex];
903 run_table = pwd->run_table[tindex];
904 level_table = pwd->level_table[tindex];
906 ptr = &pwd->coefs1[ch][0];
907 eptr = ptr + nb_coefs[ch];
908 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
910 code = get_vlc(&pwd->gb, coef_vlc);
913 if (code == 1) /* EOB */
915 if (code == 0) { /* escape */
916 level = get_bits(&pwd->gb, coef_nb_bits);
917 /* reading block_len_bits would be better */
918 run = get_bits(&pwd->gb, pwd->frame_len_bits);
919 } else { /* normal code */
920 run = run_table[code];
921 level = level_table[code];
923 if (!get_bit(&pwd->gb))
927 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
931 if (ptr >= eptr) /* EOB can be omitted */
935 compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
936 if (ms_stereo && pwd->channel_coded[1]) {
940 * Nominal case for ms stereo: we do it before mdct.
942 * No need to optimize this case because it should almost never
945 if (!pwd->channel_coded[0]) {
946 PARA_NOTICE_LOG("rare ms-stereo\n");
947 memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
948 pwd->channel_coded[0] = 1;
950 for (i = 0; i < pwd->block_len; i++) {
951 a = pwd->coefs[0][i];
952 b = pwd->coefs[1][i];
953 pwd->coefs[0][i] = a + b;
954 pwd->coefs[1][i] = a - b;
958 for (ch = 0; ch < pwd->ahi.channels; ch++) {
961 n4 = pwd->block_len / 2;
962 if (pwd->channel_coded[ch])
963 imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
964 else if (!(ms_stereo && ch == 1))
965 memset(pwd->output, 0, sizeof(pwd->output));
967 /* multiply by the window and add in the frame */
968 idx = (pwd->frame_len / 2) + pwd->block_pos - n4;
969 wma_window(pwd, &pwd->frame_out[ch][idx]);
972 /* update block number */
973 pwd->block_pos += pwd->block_len;
974 if (pwd->block_pos >= pwd->frame_len)
981 * Clip a signed integer value into the -32768,32767 range.
983 * \param a The value to clip.
985 * \return The clipped value.
987 static inline int16_t av_clip_int16(int a)
989 if ((a + 32768) & ~65535)
990 return (a >> 31) ^ 32767;
995 /* Decode a frame of frame_len samples. */
996 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1002 /* read each block */
1005 ret = wma_decode_block(pwd);
1012 /* convert frame to integer */
1013 for (ch = 0; ch < pwd->ahi.channels; ch++) {
1015 iptr = pwd->frame_out[ch];
1017 for (i = 0; i < pwd->frame_len; i++) {
1018 *ptr = av_clip_int16(lrintf(*iptr++));
1019 ptr += pwd->ahi.channels;
1021 /* prepare for next block */
1022 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1023 pwd->frame_len * sizeof(float));
1028 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *out,
1029 int *out_size, const uint8_t *in)
1031 int ret, in_size = pwd->ahi.packet_size - WMA_FRAME_SKIP;
1032 int16_t *samples = out;
1034 init_get_bits(&pwd->gb, in, in_size);
1035 if (pwd->ahi.use_bit_reservoir) {
1036 int i, nb_frames, bit_offset, pos, len;
1039 /* read super frame header */
1040 skip_bits(&pwd->gb, 4); /* super frame index */
1041 nb_frames = get_bits(&pwd->gb, 4) - 1;
1042 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1043 ret = -E_WMA_OUTPUT_SPACE;
1044 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1045 * sizeof(int16_t) > *out_size)
1048 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1050 if (pwd->last_superframe_len > 0) {
1051 /* add bit_offset bits to last frame */
1052 ret = -E_WMA_BAD_SUPERFRAME;
1053 if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1054 MAX_CODED_SUPERFRAME_SIZE)
1056 q = pwd->last_superframe + pwd->last_superframe_len;
1059 *q++ = get_bits(&pwd->gb, 8);
1063 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1065 /* XXX: bit_offset bits into last frame */
1066 init_get_bits(&pwd->gb, pwd->last_superframe,
1067 MAX_CODED_SUPERFRAME_SIZE);
1068 /* skip unused bits */
1069 if (pwd->last_bitoffset > 0)
1070 skip_bits(&pwd->gb, pwd->last_bitoffset);
1072 * This frame is stored in the last superframe and in
1075 ret = wma_decode_frame(pwd, samples);
1078 samples += pwd->ahi.channels * pwd->frame_len;
1081 /* read each frame starting from bit_offset */
1082 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1083 init_get_bits(&pwd->gb, in + (pos >> 3),
1084 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1087 skip_bits(&pwd->gb, len);
1089 pwd->reset_block_lengths = true;
1090 for (i = 0; i < nb_frames; i++) {
1091 ret = wma_decode_frame(pwd, samples);
1094 samples += pwd->ahi.channels * pwd->frame_len;
1097 /* we copy the end of the frame in the last frame buffer */
1098 pos = get_bits_count(&pwd->gb) +
1099 ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1100 pwd->last_bitoffset = pos & 7;
1102 len = in_size - pos;
1103 ret = -E_WMA_BAD_SUPERFRAME;
1104 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1106 pwd->last_superframe_len = len;
1107 memcpy(pwd->last_superframe, in + pos, len);
1109 PARA_DEBUG_LOG("not using bit reservoir\n");
1110 ret = -E_WMA_OUTPUT_SPACE;
1111 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *out_size)
1113 /* single frame decode */
1114 ret = wma_decode_frame(pwd, samples);
1117 samples += pwd->ahi.channels * pwd->frame_len;
1119 PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
1120 pwd->frame_len, pwd->block_len,
1121 (int)((int8_t *)samples - (int8_t *)out), pwd->ahi.block_align);
1122 *out_size = (int8_t *)samples - (int8_t *)out;
1123 return pwd->ahi.block_align;
1125 /* reset the bit reservoir on errors */
1126 pwd->last_superframe_len = 0;
1130 static void wmadec_close(struct filter_node *fn)
1132 struct private_wmadec_data *pwd = fn->private_data;
1137 for (i = 0; i < pwd->nb_block_sizes; i++)
1138 imdct_end(pwd->mdct_ctx[i]);
1139 if (pwd->ahi.use_exp_vlc)
1140 free_vlc(&pwd->exp_vlc);
1141 if (pwd->use_noise_coding)
1142 free_vlc(&pwd->hgain_vlc);
1143 for (i = 0; i < 2; i++) {
1144 free_vlc(&pwd->coef_vlc[i]);
1145 free(pwd->run_table[i]);
1146 free(pwd->level_table[i]);
1148 free(fn->private_data);
1149 fn->private_data = NULL;
1152 static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
1154 struct filter_node *fn = btr_context(btrn);
1155 struct private_wmadec_data *pwd = fn->private_data;
1157 return decoder_execute(cmd, pwd->ahi.sample_rate, pwd->ahi.channels,
1161 #define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
1163 static int wmadec_post_select(__a_unused struct sched *s, void *context)
1165 struct filter_node *fn = context;
1166 int ret, converted, out_size;
1167 struct private_wmadec_data *pwd = fn->private_data;
1168 struct btr_node *btrn = fn->btrn;
1174 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
1179 btr_merge(btrn, fn->min_iqs);
1180 len = btr_next_buffer(btrn, &in);
1181 ret = -E_WMADEC_EOF;
1182 if (len < fn->min_iqs)
1185 ret = wma_decode_init(in, len, &pwd);
1189 fn->min_iqs += 4096;
1192 fn->min_iqs = 2 * pwd->ahi.packet_size;
1193 fn->private_data = pwd;
1194 converted = pwd->ahi.header_len;
1197 fn->min_iqs = pwd->ahi.packet_size;
1198 if (fn->min_iqs > len)
1200 out_size = WMA_OUTPUT_BUFFER_SIZE;
1201 out = para_malloc(out_size);
1202 ret = wma_decode_superframe(pwd, out, &out_size,
1203 (uint8_t *)in + WMA_FRAME_SKIP);
1209 out = para_realloc(out, out_size);
1210 btr_add_output(out, out_size, btrn);
1213 converted += pwd->ahi.packet_size;
1215 btr_consume(btrn, converted);
1219 btr_remove_node(&fn->btrn);
1223 static void wmadec_open(struct filter_node *fn)
1225 fn->private_data = NULL;
1229 const struct filter lsg_filter_cmd_com_wmadec_user_data = {
1230 .open = wmadec_open,
1231 .close = wmadec_close,
1232 .execute = wmadec_execute,
1233 .pre_select = generic_filter_pre_select,
1234 .post_select = wmadec_post_select,