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
35 #include "bitstream.h"
42 #define BLOCK_MIN_BITS 7
43 #define BLOCK_MAX_BITS 11
44 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
46 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
48 /* XXX: find exact max size */
49 #define HIGH_BAND_MAX_SIZE 16
51 /* XXX: is it a suitable value ? */
52 #define MAX_CODED_SUPERFRAME_SIZE 16384
54 #define MAX_CHANNELS 2
56 #define NOISE_TAB_SIZE 8192
58 #define LSP_POW_BITS 7
60 struct private_wmadec_data {
61 struct asf_header_info ahi;
62 struct getbit_context gb;
63 int use_bit_reservoir;
64 int use_variable_block_len;
65 int use_exp_vlc; ///< exponent coding: 0 = lsp, 1 = vlc + delta
66 int use_noise_coding; ///< true if perceptual noise is added
69 int exponent_sizes[BLOCK_NB_SIZES];
70 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
71 int high_band_start[BLOCK_NB_SIZES]; ///< index of first coef in high band
72 int coefs_start; ///< first coded coef
73 int coefs_end[BLOCK_NB_SIZES]; ///< max number of coded coefficients
74 int exponent_high_sizes[BLOCK_NB_SIZES];
75 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
78 /* coded values in high bands */
79 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
80 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
82 /* there are two possible tables for spectral coefficients */
83 struct vlc coef_vlc[2];
84 uint16_t *run_table[2];
85 uint16_t *level_table[2];
86 uint16_t *int_table[2];
87 const struct coef_vlc_table *coef_vlcs[2];
89 int frame_len; ///< frame length in samples
90 int frame_len_bits; ///< frame_len = 1 << frame_len_bits
91 int nb_block_sizes; ///< number of block sizes
93 int reset_block_lengths;
94 int block_len_bits; ///< log2 of current block length
95 int next_block_len_bits; ///< log2 of next block length
96 int prev_block_len_bits; ///< log2 of prev block length
97 int block_len; ///< block length in samples
98 int block_pos; ///< current position in frame
99 uint8_t ms_stereo; ///< true if mid/side stereo mode
100 uint8_t channel_coded[MAX_CHANNELS]; ///< true if channel is coded
101 int exponents_bsize[MAX_CHANNELS]; ///< log2 ratio frame/exp. length
102 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
103 float max_exponent[MAX_CHANNELS];
104 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
105 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
106 float output[BLOCK_MAX_SIZE * 2];
107 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
108 float *windows[BLOCK_NB_SIZES];
109 /* output buffer for one frame and the last for IMDCT windowing */
110 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
111 /* last frame info */
112 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
114 int last_superframe_len;
115 float noise_table[NOISE_TAB_SIZE];
117 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
118 /* lsp_to_curve tables */
119 float lsp_cos_table[BLOCK_MAX_SIZE];
120 float lsp_pow_e_table[256];
121 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
122 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
126 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)
128 #define HGAINVLCBITS 9
129 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
132 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
134 DECLARE_ALIGNED(16, float, ff_sine_128[128]);
135 DECLARE_ALIGNED(16, float, ff_sine_256[256]);
136 DECLARE_ALIGNED(16, float, ff_sine_512[512]);
137 DECLARE_ALIGNED(16, float, ff_sine_1024[1024]);
138 DECLARE_ALIGNED(16, float, ff_sine_2048[2048]);
139 DECLARE_ALIGNED(16, float, ff_sine_4096[4096]);
141 static float *ff_sine_windows[6] = {
142 ff_sine_128, ff_sine_256, ff_sine_512, ff_sine_1024,
143 ff_sine_2048, ff_sine_4096
146 /* Generate a sine window. */
147 static void sine_window_init(float *window, int n)
151 for (i = 0; i < n; i++)
152 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
155 static int wmadec_cleanup(struct private_wmadec_data *s)
159 for (i = 0; i < s->nb_block_sizes; i++)
160 imdct_end(s->mdct_ctx[i]);
163 free_vlc(&s->exp_vlc);
164 if (s->use_noise_coding)
165 free_vlc(&s->hgain_vlc);
166 for (i = 0; i < 2; i++) {
167 free_vlc(&s->coef_vlc[i]);
168 free(s->run_table[i]);
169 free(s->level_table[i]);
170 free(s->int_table[i]);
175 /* XXX: use same run/length optimization as mpeg decoders */
176 //FIXME maybe split decode / encode or pass flag
177 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
178 uint16_t **plevel_table, uint16_t **pint_table,
179 const struct coef_vlc_table *vlc_table)
181 int n = vlc_table->n;
182 const uint8_t *table_bits = vlc_table->huffbits;
183 const uint32_t *table_codes = vlc_table->huffcodes;
184 const uint16_t *levels_table = vlc_table->levels;
185 uint16_t *run_table, *level_table, *int_table;
186 int i, l, j, k, level;
188 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4);
190 run_table = para_malloc(n * sizeof(uint16_t));
191 level_table = para_malloc(n * sizeof(uint16_t));
192 int_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;
208 *pint_table = int_table;
211 /* compute the scale factor band sizes for each MDCT block size */
212 static void compute_scale_factor_band_sizes(struct private_wmadec_data *s,
215 struct asf_header_info *ahi = &s->ahi;
216 int a, b, pos, lpos, k, block_len, i, j, n;
217 const uint8_t *table;
220 for (k = 0; k < s->nb_block_sizes; k++) {
221 block_len = s->frame_len >> k;
224 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
226 if (ahi->sample_rate >= 44100)
227 table = exponent_band_44100[a];
228 else if (ahi->sample_rate >= 32000)
229 table = exponent_band_32000[a];
230 else if (ahi->sample_rate >= 22050)
231 table = exponent_band_22050[a];
235 for (i = 0; i < n; i++)
236 s->exponent_bands[k][i] = table[i];
237 s->exponent_sizes[k] = n;
241 for (i = 0; i < 25; i++) {
242 a = wma_critical_freqs[i];
243 b = ahi->sample_rate;
244 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
249 s->exponent_bands[k][j++] = pos - lpos;
250 if (pos >= block_len)
254 s->exponent_sizes[k] = j;
257 /* max number of coefs */
258 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
259 /* high freq computation */
260 s->high_band_start[k] = (int) ((block_len * 2 * high_freq)
261 / ahi->sample_rate + 0.5);
262 n = s->exponent_sizes[k];
265 for (i = 0; i < n; i++) {
268 pos += s->exponent_bands[k][i];
270 if (start < s->high_band_start[k])
271 start = s->high_band_start[k];
272 if (end > s->coefs_end[k])
273 end = s->coefs_end[k];
275 s->exponent_high_bands[k][j++] = end - start;
277 s->exponent_high_sizes[k] = j;
281 static int wma_init(struct private_wmadec_data *s, int flags2, struct asf_header_info *ahi)
284 float bps1, high_freq;
289 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
290 || ahi->channels <= 0 || ahi->channels > 8
291 || ahi->bit_rate <= 0)
292 return -E_WMA_BAD_PARAMS;
294 /* compute MDCT block size */
295 if (ahi->sample_rate <= 16000) {
296 s->frame_len_bits = 9;
297 } else if (ahi->sample_rate <= 22050) {
298 s->frame_len_bits = 10;
300 s->frame_len_bits = 11;
302 s->frame_len = 1 << s->frame_len_bits;
303 if (s->use_variable_block_len) {
305 nb = ((flags2 >> 3) & 3) + 1;
306 if ((ahi->bit_rate / ahi->channels) >= 32000)
308 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
311 s->nb_block_sizes = nb + 1;
313 s->nb_block_sizes = 1;
316 /* init rate dependent parameters */
317 s->use_noise_coding = 1;
318 high_freq = ahi->sample_rate * 0.5;
320 /* wma2 rates are normalized */
321 sample_rate1 = ahi->sample_rate;
322 if (sample_rate1 >= 44100)
323 sample_rate1 = 44100;
324 else if (sample_rate1 >= 22050)
325 sample_rate1 = 22050;
326 else if (sample_rate1 >= 16000)
327 sample_rate1 = 16000;
328 else if (sample_rate1 >= 11025)
329 sample_rate1 = 11025;
330 else if (sample_rate1 >= 8000)
333 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
334 s->byte_offset_bits = wma_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
336 * Compute high frequency value and choose if noise coding should be
340 if (ahi->channels == 2)
342 if (sample_rate1 == 44100) {
344 s->use_noise_coding = 0;
346 high_freq = high_freq * 0.4;
347 } else if (sample_rate1 == 22050) {
349 s->use_noise_coding = 0;
350 else if (bps1 >= 0.72)
351 high_freq = high_freq * 0.7;
353 high_freq = high_freq * 0.6;
354 } else if (sample_rate1 == 16000) {
356 high_freq = high_freq * 0.5;
358 high_freq = high_freq * 0.3;
359 } else if (sample_rate1 == 11025) {
360 high_freq = high_freq * 0.7;
361 } else if (sample_rate1 == 8000) {
363 high_freq = high_freq * 0.5;
364 } else if (bps > 0.75) {
365 s->use_noise_coding = 0;
367 high_freq = high_freq * 0.65;
371 high_freq = high_freq * 0.75;
372 } else if (bps >= 0.6) {
373 high_freq = high_freq * 0.6;
375 high_freq = high_freq * 0.5;
378 PARA_INFO_LOG("channels=%d sample_rate=%d "
379 "bitrate=%d block_align=%d\n",
380 ahi->channels, ahi->sample_rate,
381 ahi->bit_rate, ahi->block_align);
382 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
383 "high_freq=%f bitoffset=%d\n",
384 s->frame_len, bps, bps1,
385 high_freq, s->byte_offset_bits);
386 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
387 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
389 compute_scale_factor_band_sizes(s, high_freq);
390 /* init MDCT windows : simple sinus window */
391 for (i = 0; i < s->nb_block_sizes; i++) {
393 n = 1 << (s->frame_len_bits - i);
394 sine_window_init(ff_sine_windows[s->frame_len_bits - i - 7], n);
395 s->windows[i] = ff_sine_windows[s->frame_len_bits - i - 7];
398 s->reset_block_lengths = 1;
400 if (s->use_noise_coding) {
401 /* init the noise generator */
403 s->noise_mult = 0.02;
405 s->noise_mult = 0.04;
411 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
412 for (i = 0; i < NOISE_TAB_SIZE; i++) {
413 seed = seed * 314159 + 1;
414 s->noise_table[i] = (float) ((int) seed) * norm;
419 /* choose the VLC tables for the coefficients */
421 if (ahi->sample_rate >= 32000) {
424 else if (bps1 < 1.16)
427 s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
428 s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
429 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
430 &s->int_table[0], s->coef_vlcs[0]);
431 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
432 &s->int_table[1], s->coef_vlcs[1]);
436 static void wma_lsp_to_curve_init(struct private_wmadec_data *s, int frame_len)
441 wdel = M_PI / frame_len;
442 for (i = 0; i < frame_len; i++)
443 s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
445 /* tables for x^-0.25 computation */
446 for (i = 0; i < 256; i++) {
448 s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
451 /* These two tables are needed to avoid two operations in pow_m1_4. */
453 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
454 m = (1 << LSP_POW_BITS) + i;
455 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
457 s->lsp_pow_m_table1[i] = 2 * a - b;
458 s->lsp_pow_m_table2[i] = b - a;
463 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
465 struct private_wmadec_data *s;
468 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
469 s = para_calloc(sizeof(*s));
470 ret = read_asf_header(initial_buf, len, &s->ahi);
476 s->use_exp_vlc = s->ahi.flags2 & 0x0001;
477 s->use_bit_reservoir = s->ahi.flags2 & 0x0002;
478 s->use_variable_block_len = s->ahi.flags2 & 0x0004;
480 ret = wma_init(s, s->ahi.flags2, &s->ahi);
484 for (i = 0; i < s->nb_block_sizes; i++) {
485 ret = imdct_init(s->frame_len_bits - i + 1, &s->mdct_ctx[i]);
489 if (s->use_noise_coding) {
490 PARA_INFO_LOG("using noise coding\n");
491 init_vlc(&s->hgain_vlc, HGAINVLCBITS,
492 sizeof(ff_wma_hgain_huffbits), ff_wma_hgain_huffbits,
493 1, 1, ff_wma_hgain_huffcodes, 2, 2);
496 if (s->use_exp_vlc) {
497 PARA_INFO_LOG("using exp_vlc\n");
498 init_vlc(&s->exp_vlc, EXPVLCBITS,
499 sizeof(ff_wma_scale_huffbits), ff_wma_scale_huffbits,
500 1, 1, ff_wma_scale_huffcodes, 4, 4);
502 PARA_INFO_LOG("using curve\n");
503 wma_lsp_to_curve_init(s, s->frame_len);
506 return s->ahi.header_len;
510 * compute x^-0.25 with an exponent and mantissa table. We use linear
511 * interpolation to reduce the mantissa table size at a small speed
512 * expense (linear interpolation approximately doubles the number of
513 * bits of precision).
515 static inline float pow_m1_4(struct private_wmadec_data *s, float x)
526 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
527 /* build interpolation scale: 1 <= t < 2. */
528 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
529 a = s->lsp_pow_m_table1[m];
530 b = s->lsp_pow_m_table2[m];
531 return s->lsp_pow_e_table[e] * (a + b * t.f);
534 static void wma_lsp_to_curve(struct private_wmadec_data *s,
535 float *out, float *val_max_ptr, int n, float *lsp)
538 float p, q, w, v, val_max;
541 for (i = 0; i < n; i++) {
544 w = s->lsp_cos_table[i];
545 for (j = 1; j < NB_LSP_COEFS; j += 2) {
557 *val_max_ptr = val_max;
560 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
561 static void decode_exp_lsp(struct private_wmadec_data *s, int ch)
563 float lsp_coefs[NB_LSP_COEFS];
566 for (i = 0; i < NB_LSP_COEFS; i++) {
567 if (i == 0 || i >= 8)
568 val = get_bits(&s->gb, 3);
570 val = get_bits(&s->gb, 4);
571 lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
574 wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
575 s->block_len, lsp_coefs);
579 * Parse a vlc code, faster then get_vlc().
581 * \param bits The number of bits which will be read at once, must be
582 * identical to nb_bits in init_vlc()
584 * \param max_depth The number of times bits bits must be read to completely
585 * read the longest vlc code = (max_vlc_length + bits - 1) / bits.
587 static int get_vlc2(struct getbit_context *s, VLC_TYPE(*table)[2],
588 int bits, int max_depth)
594 GET_VLC(code, re, s, table, bits, max_depth)
599 /* Decode exponents coded with VLC codes. */
600 static int decode_exp_vlc(struct private_wmadec_data *s, int ch)
602 int last_exp, n, code;
603 const uint16_t *ptr, *band_ptr;
604 float v, *q, max_scale, *q_end;
606 band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
608 q = s->exponents[ch];
609 q_end = q + s->block_len;
614 code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
617 /* NOTE: this offset is the same as MPEG4 AAC ! */
618 last_exp += code - 60;
619 /* XXX: use a table */
620 v = pow(10, last_exp * (1.0 / 16.0));
628 s->max_exponent[ch] = max_scale;
632 static void vector_fmul_add(float *dst, const float *src0, const float *src1,
633 const float *src2, int src3, int len, int step)
636 for (i = 0; i < len; i++)
637 dst[i * step] = src0[i] * src1[i] + src2[i] + src3;
640 static void vector_fmul_reverse_c(float *dst, const float *src0,
641 const float *src1, int len)
645 for (i = 0; i < len; i++)
646 dst[i] = src0[i] * src1[-i];
650 * Apply MDCT window and add into output.
652 * We ensure that when the windows overlap their squared sum
653 * is always 1 (MDCT reconstruction rule).
655 static void wma_window(struct private_wmadec_data *s, float *out)
657 float *in = s->output;
658 int block_len, bsize, n;
661 if (s->block_len_bits <= s->prev_block_len_bits) {
662 block_len = s->block_len;
663 bsize = s->frame_len_bits - s->block_len_bits;
665 vector_fmul_add(out, in, s->windows[bsize],
666 out, 0, block_len, 1);
669 block_len = 1 << s->prev_block_len_bits;
670 n = (s->block_len - block_len) / 2;
671 bsize = s->frame_len_bits - s->prev_block_len_bits;
673 vector_fmul_add(out + n, in + n, s->windows[bsize],
674 out + n, 0, block_len, 1);
676 memcpy(out + n + block_len, in + n + block_len,
684 if (s->block_len_bits <= s->next_block_len_bits) {
685 block_len = s->block_len;
686 bsize = s->frame_len_bits - s->block_len_bits;
688 vector_fmul_reverse_c(out, in, s->windows[bsize], block_len);
691 block_len = 1 << s->next_block_len_bits;
692 n = (s->block_len - block_len) / 2;
693 bsize = s->frame_len_bits - s->next_block_len_bits;
695 memcpy(out, in, n * sizeof(float));
697 vector_fmul_reverse_c(out + n, in + n, s->windows[bsize],
700 memset(out + n + block_len, 0, n * sizeof(float));
704 static int wma_total_gain_to_bits(int total_gain)
708 else if (total_gain < 32)
710 else if (total_gain < 40)
712 else if (total_gain < 45)
719 * @return 0 if OK. 1 if last block of frame. return -1 if
720 * unrecorrable error.
722 static int wma_decode_block(struct private_wmadec_data *s)
724 int n, v, ch, code, bsize;
725 int coef_nb_bits, total_gain;
726 int nb_coefs[MAX_CHANNELS];
729 /* compute current block length */
730 if (s->use_variable_block_len) {
731 n = wma_log2(s->nb_block_sizes - 1) + 1;
733 if (s->reset_block_lengths) {
734 s->reset_block_lengths = 0;
735 v = get_bits(&s->gb, n);
736 if (v >= s->nb_block_sizes)
738 s->prev_block_len_bits = s->frame_len_bits - v;
739 v = get_bits(&s->gb, n);
740 if (v >= s->nb_block_sizes)
742 s->block_len_bits = s->frame_len_bits - v;
744 /* update block lengths */
745 s->prev_block_len_bits = s->block_len_bits;
746 s->block_len_bits = s->next_block_len_bits;
748 v = get_bits(&s->gb, n);
749 if (v >= s->nb_block_sizes)
751 s->next_block_len_bits = s->frame_len_bits - v;
753 /* fixed block len */
754 s->next_block_len_bits = s->frame_len_bits;
755 s->prev_block_len_bits = s->frame_len_bits;
756 s->block_len_bits = s->frame_len_bits;
759 /* now check if the block length is coherent with the frame length */
760 s->block_len = 1 << s->block_len_bits;
761 if ((s->block_pos + s->block_len) > s->frame_len)
762 return -E_INCOHERENT_BLOCK_LEN;
764 if (s->ahi.channels == 2) {
765 s->ms_stereo = get_bits1(&s->gb);
768 for (ch = 0; ch < s->ahi.channels; ch++) {
769 int a = get_bits1(&s->gb);
770 s->channel_coded[ch] = a;
774 bsize = s->frame_len_bits - s->block_len_bits;
776 /* if no channel coded, no need to go further */
777 /* XXX: fix potential framing problems */
781 /* read total gain and extract corresponding number of bits for
782 coef escape coding */
785 int a = get_bits(&s->gb, 7);
791 coef_nb_bits = wma_total_gain_to_bits(total_gain);
793 /* compute number of coefficients */
794 n = s->coefs_end[bsize] - s->coefs_start;
795 for (ch = 0; ch < s->ahi.channels; ch++)
799 if (s->use_noise_coding) {
800 for (ch = 0; ch < s->ahi.channels; ch++) {
801 if (s->channel_coded[ch]) {
803 m = s->exponent_high_sizes[bsize];
804 for (i = 0; i < m; i++) {
805 a = get_bits1(&s->gb);
806 s->high_band_coded[ch][i] = a;
807 /* if noise coding, the coefficients are not transmitted */
811 exponent_high_bands[bsize]
816 for (ch = 0; ch < s->ahi.channels; ch++) {
817 if (s->channel_coded[ch]) {
820 n = s->exponent_high_sizes[bsize];
821 val = (int) 0x80000000;
822 for (i = 0; i < n; i++) {
823 if (s->high_band_coded[ch][i]) {
824 if (val == (int) 0x80000000) {
840 s->high_band_values[ch][i] =
848 /* exponents can be reused in short blocks. */
849 if ((s->block_len_bits == s->frame_len_bits) || get_bits1(&s->gb)) {
850 for (ch = 0; ch < s->ahi.channels; ch++) {
851 if (s->channel_coded[ch]) {
852 if (s->use_exp_vlc) {
853 if (decode_exp_vlc(s, ch) < 0)
856 decode_exp_lsp(s, ch);
858 s->exponents_bsize[ch] = bsize;
863 /* parse spectral coefficients : just RLE encoding */
864 for (ch = 0; ch < s->ahi.channels; ch++) {
865 if (s->channel_coded[ch]) {
866 struct vlc *coef_vlc;
867 int level, run, sign, tindex;
869 const uint16_t *level_table, *run_table;
871 /* special VLC tables are used for ms stereo because
872 there is potentially less energy there */
873 tindex = (ch == 1 && s->ms_stereo);
874 coef_vlc = &s->coef_vlc[tindex];
875 run_table = s->run_table[tindex];
876 level_table = s->level_table[tindex];
878 ptr = &s->coefs1[ch][0];
879 eptr = ptr + nb_coefs[ch];
880 memset(ptr, 0, s->block_len * sizeof(int16_t));
883 get_vlc2(&s->gb, coef_vlc->table, VLCBITS,
890 } else if (code == 0) {
892 level = get_bits(&s->gb, coef_nb_bits);
893 /* NOTE: this is rather suboptimal. reading
894 block_len_bits would be better */
896 get_bits(&s->gb, s->frame_len_bits);
899 run = run_table[code];
900 level = level_table[code];
902 sign = get_bits1(&s->gb);
907 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
911 /* NOTE: EOB can be omitted */
920 int n4 = s->block_len / 2;
921 mdct_norm = 1.0 / (float) n4;
924 /* finally compute the MDCT coefficients */
925 for (ch = 0; ch < s->ahi.channels; ch++) {
926 if (s->channel_coded[ch]) {
928 float *coefs, *exponents, mult, mult1, noise;
929 int i, j, n1, last_high_band, esize;
930 float exp_power[HIGH_BAND_MAX_SIZE];
932 coefs1 = s->coefs1[ch];
933 exponents = s->exponents[ch];
934 esize = s->exponents_bsize[ch];
935 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
937 coefs = s->coefs[ch];
938 if (s->use_noise_coding) {
940 /* very low freqs : noise */
941 for (i = 0; i < s->coefs_start; i++) {
943 s->noise_table[s->noise_index] *
944 exponents[i << bsize >> esize] *
948 1) & (NOISE_TAB_SIZE - 1);
951 n1 = s->exponent_high_sizes[bsize];
953 /* compute power of high bands */
954 exponents = s->exponents[ch] +
955 (s->high_band_start[bsize] << bsize);
956 last_high_band = 0; /* avoid warning */
957 for (j = 0; j < n1; j++) {
958 n = s->exponent_high_bands[s->
964 if (s->high_band_coded[ch][j]) {
967 for (i = 0; i < n; i++) {
968 val = exponents[i << bsize
972 exp_power[j] = e2 / n;
975 exponents += n << bsize;
978 /* main freqs and high freqs */
981 (s->coefs_start << bsize);
982 for (j = -1; j < n1; j++) {
984 n = s->high_band_start[bsize] -
987 n = s->exponent_high_bands[s->
994 if (j >= 0 && s->high_band_coded[ch][j]) {
995 /* use noise with specified power */
1000 /* XXX: use a table */
1008 (s->max_exponent[ch] *
1011 for (i = 0; i < n; i++) {
1022 exponents[i << bsize
1026 exponents += n << bsize;
1028 /* coded values + small noise */
1029 for (i = 0; i < n; i++) {
1041 exponents[i << bsize
1045 exponents += n << bsize;
1049 /* very high freqs : noise */
1050 n = s->block_len - s->coefs_end[bsize];
1052 mult * exponents[((-1 << bsize)) >> esize];
1053 for (i = 0; i < n; i++) {
1055 s->noise_table[s->noise_index] *
1059 1) & (NOISE_TAB_SIZE - 1);
1062 /* XXX: optimize more */
1063 for (i = 0; i < s->coefs_start; i++)
1066 for (i = 0; i < n; i++) {
1069 exponents[i << bsize >> esize] *
1072 n = s->block_len - s->coefs_end[bsize];
1073 for (i = 0; i < n; i++)
1079 if (s->ms_stereo && s->channel_coded[1]) {
1084 * Nominal case for ms stereo: we do it before mdct.
1086 * No need to optimize this case because it should almost never
1089 if (!s->channel_coded[0]) {
1090 PARA_NOTICE_LOG("rare ms-stereo\n");
1091 memset(s->coefs[0], 0, sizeof(float) * s->block_len);
1092 s->channel_coded[0] = 1;
1094 for (i = 0; i < s->block_len; i++) {
1097 s->coefs[0][i] = a + b;
1098 s->coefs[1][i] = a - b;
1103 for (ch = 0; ch < s->ahi.channels; ch++) {
1107 n4 = s->block_len / 2;
1108 if (s->channel_coded[ch])
1109 imdct(s->mdct_ctx[bsize], s->output, s->coefs[ch]);
1110 else if (!(s->ms_stereo && ch == 1))
1111 memset(s->output, 0, sizeof(s->output));
1113 /* multiply by the window and add in the frame */
1114 index = (s->frame_len / 2) + s->block_pos - n4;
1115 wma_window(s, &s->frame_out[ch][index]);
1118 /* update block number */
1119 s->block_pos += s->block_len;
1120 if (s->block_pos >= s->frame_len)
1127 * Clip a signed integer value into the -32768,32767 range.
1129 * \param a The value to clip.
1131 * \return The clipped value.
1133 static inline int16_t av_clip_int16(int a)
1135 if ((a + 32768) & ~65535)
1136 return (a >> 31) ^ 32767;
1141 /* Decode a frame of frame_len samples. */
1142 static int wma_decode_frame(struct private_wmadec_data *s, int16_t * samples)
1144 int ret, i, n, ch, incr;
1148 /* read each block */
1151 ret = wma_decode_block(s);
1158 /* convert frame to integer */
1160 incr = s->ahi.channels;
1161 for (ch = 0; ch < s->ahi.channels; ch++) {
1163 iptr = s->frame_out[ch];
1165 for (i = 0; i < n; i++) {
1166 *ptr = av_clip_int16(lrintf(*iptr++));
1169 /* prepare for next block */
1170 memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
1171 s->frame_len * sizeof(float));
1176 static int wma_decode_superframe(struct private_wmadec_data *s, void *data,
1177 int *data_size, const uint8_t *buf, int buf_size)
1179 int ret, nb_frames, bit_offset, i, pos, len;
1182 static int frame_count;
1184 if (buf_size == 0) {
1185 s->last_superframe_len = 0;
1188 if (buf_size < s->ahi.block_align)
1190 buf_size = s->ahi.block_align;
1192 init_get_bits(&s->gb, buf, buf_size * 8);
1193 if (s->use_bit_reservoir) {
1194 /* read super frame header */
1195 skip_bits(&s->gb, 4); /* super frame index */
1196 nb_frames = get_bits(&s->gb, 4) - 1;
1197 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1198 ret = -E_WMA_OUTPUT_SPACE;
1199 if ((nb_frames + 1) * s->ahi.channels * s->frame_len
1200 * sizeof(int16_t) > *data_size)
1203 bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
1205 if (s->last_superframe_len > 0) {
1206 /* add bit_offset bits to last frame */
1207 ret = -E_WMA_BAD_SUPERFRAME;
1208 if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
1209 MAX_CODED_SUPERFRAME_SIZE)
1211 q = s->last_superframe + s->last_superframe_len;
1214 *q++ = get_bits(&s->gb, 8);
1218 *q++ = get_bits(&s->gb, len) << (8 - len);
1221 /* XXX: bit_offset bits into last frame */
1222 init_get_bits(&s->gb, s->last_superframe,
1223 MAX_CODED_SUPERFRAME_SIZE * 8);
1224 /* skip unused bits */
1225 if (s->last_bitoffset > 0)
1226 skip_bits(&s->gb, s->last_bitoffset);
1228 * This frame is stored in the last superframe and in
1231 ret = -E_WMA_DECODE;
1232 if (wma_decode_frame(s, samples) < 0)
1235 samples += s->ahi.channels * s->frame_len;
1238 /* read each frame starting from bit_offset */
1239 pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
1240 init_get_bits(&s->gb, buf + (pos >> 3),
1241 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)) * 8);
1244 skip_bits(&s->gb, len);
1246 s->reset_block_lengths = 1;
1247 for (i = 0; i < nb_frames; i++) {
1248 ret = -E_WMA_DECODE;
1249 if (wma_decode_frame(s, samples) < 0)
1252 samples += s->ahi.channels * s->frame_len;
1255 /* we copy the end of the frame in the last frame buffer */
1256 pos = get_bits_count(&s->gb) +
1257 ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
1258 s->last_bitoffset = pos & 7;
1260 len = buf_size - pos;
1261 ret = -E_WMA_BAD_SUPERFRAME;
1262 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
1265 s->last_superframe_len = len;
1266 memcpy(s->last_superframe, buf + pos, len);
1268 PARA_DEBUG_LOG("not using bit reservoir\n");
1269 ret = -E_WMA_OUTPUT_SPACE;
1270 if (s->ahi.channels * s->frame_len * sizeof(int16_t) > *data_size)
1272 /* single frame decode */
1273 ret = -E_WMA_DECODE;
1274 if (wma_decode_frame(s, samples) < 0)
1277 samples += s->ahi.channels * s->frame_len;
1279 PARA_DEBUG_LOG("frame_count: %d frame_len: %d, block_len: %d, "
1280 "outbytes: %d, eaten: %d\n",
1281 frame_count, s->frame_len, s->block_len,
1282 (int8_t *) samples - (int8_t *) data, s->ahi.block_align);
1283 *data_size = (int8_t *)samples - (int8_t *)data;
1284 return s->ahi.block_align;
1286 /* reset the bit reservoir on errors */
1287 s->last_superframe_len = 0;
1291 static ssize_t wmadec_convert(char *inbuffer, size_t len,
1292 struct filter_node *fn)
1294 int ret, out_size = fn->bufsize - fn->loaded;
1295 struct private_wmadec_data *pwd = fn->private_data;
1297 if (out_size < 128 * 1024)
1300 ret = wma_decode_init(inbuffer, len, &pwd);
1303 fn->private_data = pwd;
1304 fn->fc->channels = pwd->ahi.channels;
1305 fn->fc->samplerate = pwd->ahi.sample_rate;
1306 return pwd->ahi.header_len;
1309 if (len <= WMA_FRAME_SKIP + pwd->ahi.block_align)
1311 ret = wma_decode_superframe(pwd, fn->buf + fn->loaded,
1312 &out_size, (uint8_t *)inbuffer + WMA_FRAME_SKIP,
1313 len - WMA_FRAME_SKIP);
1316 fn->loaded += out_size;
1317 return ret + WMA_FRAME_SKIP;
1320 static void wmadec_close(struct filter_node *fn)
1322 struct private_wmadec_data *pwd = fn->private_data;
1325 wmadec_cleanup(pwd);
1328 free(fn->private_data);
1329 fn->private_data = NULL;
1332 static void wmadec_open(struct filter_node *fn)
1334 fn->bufsize = 1024 * 1024;
1335 fn->buf = para_malloc(fn->bufsize);
1336 fn->private_data = NULL;
1341 * The init function of the wma decoder.
1343 * \param f Its fields are filled in by the function.
1345 void wmadec_filter_init(struct filter *f)
1347 f->open = wmadec_open;
1348 f->close = wmadec_close;
1349 f->convert = wmadec_convert;