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
36 #include "bitstream.h"
43 #define BLOCK_MIN_BITS 7
44 #define BLOCK_MAX_BITS 11
45 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
47 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
49 /* XXX: find exact max size */
50 #define HIGH_BAND_MAX_SIZE 16
52 /* XXX: is it a suitable value ? */
53 #define MAX_CODED_SUPERFRAME_SIZE 16384
55 #define MAX_CHANNELS 2
57 #define NOISE_TAB_SIZE 8192
59 #define LSP_POW_BITS 7
61 struct private_wmadec_data {
62 struct asf_header_info ahi;
63 struct getbit_context gb;
64 int use_bit_reservoir;
65 int use_variable_block_len;
66 int use_exp_vlc; ///< exponent coding: 0 = lsp, 1 = vlc + delta
67 int use_noise_coding; ///< true if perceptual noise is added
70 int exponent_sizes[BLOCK_NB_SIZES];
71 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
72 int high_band_start[BLOCK_NB_SIZES]; ///< index of first coef in high band
73 int coefs_start; ///< first coded coef
74 int coefs_end[BLOCK_NB_SIZES]; ///< max number of coded coefficients
75 int exponent_high_sizes[BLOCK_NB_SIZES];
76 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
79 /* coded values in high bands */
80 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
81 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
83 /* there are two possible tables for spectral coefficients */
84 struct vlc coef_vlc[2];
85 uint16_t *run_table[2];
86 uint16_t *level_table[2];
87 uint16_t *int_table[2];
88 const struct coef_vlc_table *coef_vlcs[2];
90 int frame_len; ///< frame length in samples
91 int frame_len_bits; ///< frame_len = 1 << frame_len_bits
92 int nb_block_sizes; ///< number of block sizes
94 int reset_block_lengths;
95 int block_len_bits; ///< log2 of current block length
96 int next_block_len_bits; ///< log2 of next block length
97 int prev_block_len_bits; ///< log2 of prev block length
98 int block_len; ///< block length in samples
99 int block_pos; ///< current position in frame
100 uint8_t ms_stereo; ///< true if mid/side stereo mode
101 uint8_t channel_coded[MAX_CHANNELS]; ///< true if channel is coded
102 int exponents_bsize[MAX_CHANNELS]; ///< log2 ratio frame/exp. length
103 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
104 float max_exponent[MAX_CHANNELS];
105 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
106 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
107 float output[BLOCK_MAX_SIZE * 2];
108 struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
109 float *windows[BLOCK_NB_SIZES];
110 /* output buffer for one frame and the last for IMDCT windowing */
111 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
112 /* last frame info */
113 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
115 int last_superframe_len;
116 float noise_table[NOISE_TAB_SIZE];
118 float noise_mult; /* XXX: suppress that and integrate it in the noise array */
119 /* lsp_to_curve tables */
120 float lsp_cos_table[BLOCK_MAX_SIZE];
121 float lsp_pow_e_table[256];
122 float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
123 float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
127 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)
129 #define HGAINVLCBITS 9
130 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
133 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
135 static int wmadec_cleanup(struct private_wmadec_data *s)
139 for (i = 0; i < s->nb_block_sizes; i++)
140 imdct_end(s->mdct_ctx[i]);
143 free_vlc(&s->exp_vlc);
144 if (s->use_noise_coding)
145 free_vlc(&s->hgain_vlc);
146 for (i = 0; i < 2; i++) {
147 free_vlc(&s->coef_vlc[i]);
148 free(s->run_table[i]);
149 free(s->level_table[i]);
150 free(s->int_table[i]);
155 /* XXX: use same run/length optimization as mpeg decoders */
156 //FIXME maybe split decode / encode or pass flag
157 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
158 uint16_t **plevel_table, uint16_t **pint_table,
159 const struct coef_vlc_table *vlc_table)
161 int n = vlc_table->n;
162 const uint8_t *table_bits = vlc_table->huffbits;
163 const uint32_t *table_codes = vlc_table->huffcodes;
164 const uint16_t *levels_table = vlc_table->levels;
165 uint16_t *run_table, *level_table, *int_table;
166 int i, l, j, k, level;
168 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4);
170 run_table = para_malloc(n * sizeof(uint16_t));
171 level_table = para_malloc(n * sizeof(uint16_t));
172 int_table = para_malloc(n * sizeof(uint16_t));
178 l = levels_table[k++];
179 for (j = 0; j < l; j++) {
181 level_table[i] = level;
186 *prun_table = run_table;
187 *plevel_table = level_table;
188 *pint_table = int_table;
191 /* compute the scale factor band sizes for each MDCT block size */
192 static void compute_scale_factor_band_sizes(struct private_wmadec_data *s,
195 struct asf_header_info *ahi = &s->ahi;
196 int a, b, pos, lpos, k, block_len, i, j, n;
197 const uint8_t *table;
200 for (k = 0; k < s->nb_block_sizes; k++) {
201 block_len = s->frame_len >> k;
204 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
206 if (ahi->sample_rate >= 44100)
207 table = exponent_band_44100[a];
208 else if (ahi->sample_rate >= 32000)
209 table = exponent_band_32000[a];
210 else if (ahi->sample_rate >= 22050)
211 table = exponent_band_22050[a];
215 for (i = 0; i < n; i++)
216 s->exponent_bands[k][i] = table[i];
217 s->exponent_sizes[k] = n;
221 for (i = 0; i < 25; i++) {
222 a = wma_critical_freqs[i];
223 b = ahi->sample_rate;
224 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
229 s->exponent_bands[k][j++] = pos - lpos;
230 if (pos >= block_len)
234 s->exponent_sizes[k] = j;
237 /* max number of coefs */
238 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
239 /* high freq computation */
240 s->high_band_start[k] = (int) ((block_len * 2 * high_freq)
241 / ahi->sample_rate + 0.5);
242 n = s->exponent_sizes[k];
245 for (i = 0; i < n; i++) {
248 pos += s->exponent_bands[k][i];
250 if (start < s->high_band_start[k])
251 start = s->high_band_start[k];
252 if (end > s->coefs_end[k])
253 end = s->coefs_end[k];
255 s->exponent_high_bands[k][j++] = end - start;
257 s->exponent_high_sizes[k] = j;
261 static int wma_init(struct private_wmadec_data *s, int flags2, struct asf_header_info *ahi)
264 float bps1, high_freq;
269 if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
270 || ahi->channels <= 0 || ahi->channels > 8
271 || ahi->bit_rate <= 0)
272 return -E_WMA_BAD_PARAMS;
274 /* compute MDCT block size */
275 if (ahi->sample_rate <= 16000) {
276 s->frame_len_bits = 9;
277 } else if (ahi->sample_rate <= 22050) {
278 s->frame_len_bits = 10;
280 s->frame_len_bits = 11;
282 s->frame_len = 1 << s->frame_len_bits;
283 if (s->use_variable_block_len) {
285 nb = ((flags2 >> 3) & 3) + 1;
286 if ((ahi->bit_rate / ahi->channels) >= 32000)
288 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
291 s->nb_block_sizes = nb + 1;
293 s->nb_block_sizes = 1;
296 /* init rate dependent parameters */
297 s->use_noise_coding = 1;
298 high_freq = ahi->sample_rate * 0.5;
300 /* wma2 rates are normalized */
301 sample_rate1 = ahi->sample_rate;
302 if (sample_rate1 >= 44100)
303 sample_rate1 = 44100;
304 else if (sample_rate1 >= 22050)
305 sample_rate1 = 22050;
306 else if (sample_rate1 >= 16000)
307 sample_rate1 = 16000;
308 else if (sample_rate1 >= 11025)
309 sample_rate1 = 11025;
310 else if (sample_rate1 >= 8000)
313 bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
314 s->byte_offset_bits = wma_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
316 * Compute high frequency value and choose if noise coding should be
320 if (ahi->channels == 2)
322 if (sample_rate1 == 44100) {
324 s->use_noise_coding = 0;
326 high_freq = high_freq * 0.4;
327 } else if (sample_rate1 == 22050) {
329 s->use_noise_coding = 0;
330 else if (bps1 >= 0.72)
331 high_freq = high_freq * 0.7;
333 high_freq = high_freq * 0.6;
334 } else if (sample_rate1 == 16000) {
336 high_freq = high_freq * 0.5;
338 high_freq = high_freq * 0.3;
339 } else if (sample_rate1 == 11025) {
340 high_freq = high_freq * 0.7;
341 } else if (sample_rate1 == 8000) {
343 high_freq = high_freq * 0.5;
344 } else if (bps > 0.75) {
345 s->use_noise_coding = 0;
347 high_freq = high_freq * 0.65;
351 high_freq = high_freq * 0.75;
352 } else if (bps >= 0.6) {
353 high_freq = high_freq * 0.6;
355 high_freq = high_freq * 0.5;
358 PARA_INFO_LOG("channels=%d sample_rate=%d "
359 "bitrate=%d block_align=%d\n",
360 ahi->channels, ahi->sample_rate,
361 ahi->bit_rate, ahi->block_align);
362 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
363 "high_freq=%f bitoffset=%d\n",
364 s->frame_len, bps, bps1,
365 high_freq, s->byte_offset_bits);
366 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
367 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
369 compute_scale_factor_band_sizes(s, high_freq);
370 /* init MDCT windows : simple sinus window */
371 for (i = 0; i < s->nb_block_sizes; i++) {
373 n = 1 << (s->frame_len_bits - i);
374 sine_window_init(ff_sine_windows[s->frame_len_bits - i - 7], n);
375 s->windows[i] = ff_sine_windows[s->frame_len_bits - i - 7];
378 s->reset_block_lengths = 1;
380 if (s->use_noise_coding) {
381 /* init the noise generator */
383 s->noise_mult = 0.02;
385 s->noise_mult = 0.04;
391 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
392 for (i = 0; i < NOISE_TAB_SIZE; i++) {
393 seed = seed * 314159 + 1;
394 s->noise_table[i] = (float) ((int) seed) * norm;
399 /* choose the VLC tables for the coefficients */
401 if (ahi->sample_rate >= 32000) {
404 else if (bps1 < 1.16)
407 s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
408 s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
409 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
410 &s->int_table[0], s->coef_vlcs[0]);
411 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
412 &s->int_table[1], s->coef_vlcs[1]);
416 static void wma_lsp_to_curve_init(struct private_wmadec_data *s, int frame_len)
421 wdel = M_PI / frame_len;
422 for (i = 0; i < frame_len; i++)
423 s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
425 /* tables for x^-0.25 computation */
426 for (i = 0; i < 256; i++) {
428 s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
431 /* These two tables are needed to avoid two operations in pow_m1_4. */
433 for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
434 m = (1 << LSP_POW_BITS) + i;
435 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
437 s->lsp_pow_m_table1[i] = 2 * a - b;
438 s->lsp_pow_m_table2[i] = b - a;
443 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
445 struct private_wmadec_data *s;
448 PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
449 s = para_calloc(sizeof(*s));
450 ret = read_asf_header(initial_buf, len, &s->ahi);
456 s->use_exp_vlc = s->ahi.flags2 & 0x0001;
457 s->use_bit_reservoir = s->ahi.flags2 & 0x0002;
458 s->use_variable_block_len = s->ahi.flags2 & 0x0004;
460 ret = wma_init(s, s->ahi.flags2, &s->ahi);
464 for (i = 0; i < s->nb_block_sizes; i++) {
465 ret = imdct_init(s->frame_len_bits - i + 1, 1, &s->mdct_ctx[i]);
469 if (s->use_noise_coding) {
470 PARA_INFO_LOG("using noise coding\n");
471 init_vlc(&s->hgain_vlc, HGAINVLCBITS,
472 sizeof(ff_wma_hgain_huffbits), ff_wma_hgain_huffbits,
473 1, 1, ff_wma_hgain_huffcodes, 2, 2);
476 if (s->use_exp_vlc) {
477 PARA_INFO_LOG("using exp_vlc\n");
478 init_vlc(&s->exp_vlc, EXPVLCBITS,
479 sizeof(ff_wma_scale_huffbits), ff_wma_scale_huffbits,
480 1, 1, ff_wma_scale_huffcodes, 4, 4);
482 PARA_INFO_LOG("using curve\n");
483 wma_lsp_to_curve_init(s, s->frame_len);
486 return s->ahi.header_len;
490 * compute x^-0.25 with an exponent and mantissa table. We use linear
491 * interpolation to reduce the mantissa table size at a small speed
492 * expense (linear interpolation approximately doubles the number of
493 * bits of precision).
495 static inline float pow_m1_4(struct private_wmadec_data *s, float x)
506 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
507 /* build interpolation scale: 1 <= t < 2. */
508 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
509 a = s->lsp_pow_m_table1[m];
510 b = s->lsp_pow_m_table2[m];
511 return s->lsp_pow_e_table[e] * (a + b * t.f);
514 static void wma_lsp_to_curve(struct private_wmadec_data *s,
515 float *out, float *val_max_ptr, int n, float *lsp)
518 float p, q, w, v, val_max;
521 for (i = 0; i < n; i++) {
524 w = s->lsp_cos_table[i];
525 for (j = 1; j < NB_LSP_COEFS; j += 2) {
537 *val_max_ptr = val_max;
540 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
541 static void decode_exp_lsp(struct private_wmadec_data *s, int ch)
543 float lsp_coefs[NB_LSP_COEFS];
546 for (i = 0; i < NB_LSP_COEFS; i++) {
547 if (i == 0 || i >= 8)
548 val = get_bits(&s->gb, 3);
550 val = get_bits(&s->gb, 4);
551 lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
554 wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
555 s->block_len, lsp_coefs);
559 * Parse a vlc code, faster then get_vlc().
561 * \param bits The number of bits which will be read at once, must be
562 * identical to nb_bits in init_vlc()
564 * \param max_depth The number of times bits bits must be read to completely
565 * read the longest vlc code = (max_vlc_length + bits - 1) / bits.
567 static int get_vlc2(struct getbit_context *s, VLC_TYPE(*table)[2],
568 int bits, int max_depth)
574 GET_VLC(code, re, s, table, bits, max_depth)
579 /* Decode exponents coded with VLC codes. */
580 static int decode_exp_vlc(struct private_wmadec_data *s, int ch)
582 int last_exp, n, code;
583 const uint16_t *ptr, *band_ptr;
584 float v, *q, max_scale, *q_end;
586 band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
588 q = s->exponents[ch];
589 q_end = q + s->block_len;
594 code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
597 /* NOTE: this offset is the same as MPEG4 AAC ! */
598 last_exp += code - 60;
599 /* XXX: use a table */
600 v = pow(10, last_exp * (1.0 / 16.0));
608 s->max_exponent[ch] = max_scale;
612 static void vector_fmul_add(float *dst, const float *src0, const float *src1,
613 const float *src2, int src3, int len, int step)
616 for (i = 0; i < len; i++)
617 dst[i * step] = src0[i] * src1[i] + src2[i] + src3;
620 static void vector_fmul_reverse_c(float *dst, const float *src0,
621 const float *src1, int len)
625 for (i = 0; i < len; i++)
626 dst[i] = src0[i] * src1[-i];
630 * Apply MDCT window and add into output.
632 * We ensure that when the windows overlap their squared sum
633 * is always 1 (MDCT reconstruction rule).
635 static void wma_window(struct private_wmadec_data *s, float *out)
637 float *in = s->output;
638 int block_len, bsize, n;
641 if (s->block_len_bits <= s->prev_block_len_bits) {
642 block_len = s->block_len;
643 bsize = s->frame_len_bits - s->block_len_bits;
645 vector_fmul_add(out, in, s->windows[bsize],
646 out, 0, block_len, 1);
649 block_len = 1 << s->prev_block_len_bits;
650 n = (s->block_len - block_len) / 2;
651 bsize = s->frame_len_bits - s->prev_block_len_bits;
653 vector_fmul_add(out + n, in + n, s->windows[bsize],
654 out + n, 0, block_len, 1);
656 memcpy(out + n + block_len, in + n + block_len,
664 if (s->block_len_bits <= s->next_block_len_bits) {
665 block_len = s->block_len;
666 bsize = s->frame_len_bits - s->block_len_bits;
668 vector_fmul_reverse_c(out, in, s->windows[bsize], block_len);
671 block_len = 1 << s->next_block_len_bits;
672 n = (s->block_len - block_len) / 2;
673 bsize = s->frame_len_bits - s->next_block_len_bits;
675 memcpy(out, in, n * sizeof(float));
677 vector_fmul_reverse_c(out + n, in + n, s->windows[bsize],
680 memset(out + n + block_len, 0, n * sizeof(float));
684 static int wma_total_gain_to_bits(int total_gain)
688 else if (total_gain < 32)
690 else if (total_gain < 40)
692 else if (total_gain < 45)
699 * @return 0 if OK. 1 if last block of frame. return -1 if
700 * unrecorrable error.
702 static int wma_decode_block(struct private_wmadec_data *s)
704 int n, v, ch, code, bsize;
705 int coef_nb_bits, total_gain;
706 int nb_coefs[MAX_CHANNELS];
709 /* compute current block length */
710 if (s->use_variable_block_len) {
711 n = wma_log2(s->nb_block_sizes - 1) + 1;
713 if (s->reset_block_lengths) {
714 s->reset_block_lengths = 0;
715 v = get_bits(&s->gb, n);
716 if (v >= s->nb_block_sizes)
718 s->prev_block_len_bits = s->frame_len_bits - v;
719 v = get_bits(&s->gb, n);
720 if (v >= s->nb_block_sizes)
722 s->block_len_bits = s->frame_len_bits - v;
724 /* update block lengths */
725 s->prev_block_len_bits = s->block_len_bits;
726 s->block_len_bits = s->next_block_len_bits;
728 v = get_bits(&s->gb, n);
729 if (v >= s->nb_block_sizes)
731 s->next_block_len_bits = s->frame_len_bits - v;
733 /* fixed block len */
734 s->next_block_len_bits = s->frame_len_bits;
735 s->prev_block_len_bits = s->frame_len_bits;
736 s->block_len_bits = s->frame_len_bits;
739 /* now check if the block length is coherent with the frame length */
740 s->block_len = 1 << s->block_len_bits;
741 if ((s->block_pos + s->block_len) > s->frame_len)
742 return -E_INCOHERENT_BLOCK_LEN;
744 if (s->ahi.channels == 2) {
745 s->ms_stereo = get_bits1(&s->gb);
748 for (ch = 0; ch < s->ahi.channels; ch++) {
749 int a = get_bits1(&s->gb);
750 s->channel_coded[ch] = a;
754 bsize = s->frame_len_bits - s->block_len_bits;
756 /* if no channel coded, no need to go further */
757 /* XXX: fix potential framing problems */
761 /* read total gain and extract corresponding number of bits for
762 coef escape coding */
765 int a = get_bits(&s->gb, 7);
771 coef_nb_bits = wma_total_gain_to_bits(total_gain);
773 /* compute number of coefficients */
774 n = s->coefs_end[bsize] - s->coefs_start;
775 for (ch = 0; ch < s->ahi.channels; ch++)
779 if (s->use_noise_coding) {
781 for (ch = 0; ch < s->ahi.channels; ch++) {
782 if (s->channel_coded[ch]) {
784 m = s->exponent_high_sizes[bsize];
785 for (i = 0; i < m; i++) {
786 a = get_bits1(&s->gb);
787 s->high_band_coded[ch][i] = a;
788 /* if noise coding, the coefficients are not transmitted */
792 exponent_high_bands[bsize]
797 for (ch = 0; ch < s->ahi.channels; ch++) {
798 if (s->channel_coded[ch]) {
801 n = s->exponent_high_sizes[bsize];
802 val = (int) 0x80000000;
803 for (i = 0; i < n; i++) {
804 if (s->high_band_coded[ch][i]) {
805 if (val == (int) 0x80000000) {
821 s->high_band_values[ch][i] =
829 /* exponents can be reused in short blocks. */
830 if ((s->block_len_bits == s->frame_len_bits) || get_bits1(&s->gb)) {
831 for (ch = 0; ch < s->ahi.channels; ch++) {
832 if (s->channel_coded[ch]) {
833 if (s->use_exp_vlc) {
834 if (decode_exp_vlc(s, ch) < 0)
837 decode_exp_lsp(s, ch);
839 s->exponents_bsize[ch] = bsize;
844 /* parse spectral coefficients : just RLE encoding */
845 for (ch = 0; ch < s->ahi.channels; ch++) {
846 if (s->channel_coded[ch]) {
847 struct vlc *coef_vlc;
848 int level, run, sign, tindex;
850 const uint16_t *level_table, *run_table;
852 /* special VLC tables are used for ms stereo because
853 there is potentially less energy there */
854 tindex = (ch == 1 && s->ms_stereo);
855 coef_vlc = &s->coef_vlc[tindex];
856 run_table = s->run_table[tindex];
857 level_table = s->level_table[tindex];
859 ptr = &s->coefs1[ch][0];
860 eptr = ptr + nb_coefs[ch];
861 memset(ptr, 0, s->block_len * sizeof(int16_t));
864 get_vlc2(&s->gb, coef_vlc->table, VLCBITS,
871 } else if (code == 0) {
873 level = get_bits(&s->gb, coef_nb_bits);
874 /* NOTE: this is rather suboptimal. reading
875 block_len_bits would be better */
877 get_bits(&s->gb, s->frame_len_bits);
880 run = run_table[code];
881 level = level_table[code];
883 sign = get_bits1(&s->gb);
888 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
892 /* NOTE: EOB can be omitted */
901 int n4 = s->block_len / 2;
902 mdct_norm = 1.0 / (float) n4;
905 /* finally compute the MDCT coefficients */
906 for (ch = 0; ch < s->ahi.channels; ch++) {
907 if (s->channel_coded[ch]) {
909 float *coefs, *exponents, mult, mult1, noise;
910 int i, j, n1, last_high_band, esize;
911 float exp_power[HIGH_BAND_MAX_SIZE];
913 coefs1 = s->coefs1[ch];
914 exponents = s->exponents[ch];
915 esize = s->exponents_bsize[ch];
916 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
918 coefs = s->coefs[ch];
919 if (s->use_noise_coding) {
921 /* very low freqs : noise */
922 for (i = 0; i < s->coefs_start; i++) {
924 s->noise_table[s->noise_index] *
925 exponents[i << bsize >> esize] *
929 1) & (NOISE_TAB_SIZE - 1);
932 n1 = s->exponent_high_sizes[bsize];
934 /* compute power of high bands */
935 exponents = s->exponents[ch] +
936 (s->high_band_start[bsize] << bsize);
937 last_high_band = 0; /* avoid warning */
938 for (j = 0; j < n1; j++) {
939 n = s->exponent_high_bands[s->
945 if (s->high_band_coded[ch][j]) {
948 for (i = 0; i < n; i++) {
949 val = exponents[i << bsize
953 exp_power[j] = e2 / n;
956 exponents += n << bsize;
959 /* main freqs and high freqs */
962 (s->coefs_start << bsize);
963 for (j = -1; j < n1; j++) {
965 n = s->high_band_start[bsize] -
968 n = s->exponent_high_bands[s->
975 if (j >= 0 && s->high_band_coded[ch][j]) {
976 /* use noise with specified power */
981 /* XXX: use a table */
989 (s->max_exponent[ch] *
992 for (i = 0; i < n; i++) {
1003 exponents[i << bsize
1007 exponents += n << bsize;
1009 /* coded values + small noise */
1010 for (i = 0; i < n; i++) {
1022 exponents[i << bsize
1026 exponents += n << bsize;
1030 /* very high freqs : noise */
1031 n = s->block_len - s->coefs_end[bsize];
1033 mult * exponents[((-1 << bsize)) >> esize];
1034 for (i = 0; i < n; i++) {
1036 s->noise_table[s->noise_index] *
1040 1) & (NOISE_TAB_SIZE - 1);
1043 /* XXX: optimize more */
1044 for (i = 0; i < s->coefs_start; i++)
1047 for (i = 0; i < n; i++) {
1050 exponents[i << bsize >> esize] *
1053 n = s->block_len - s->coefs_end[bsize];
1054 for (i = 0; i < n; i++)
1060 if (s->ms_stereo && s->channel_coded[1]) {
1065 * Nominal case for ms stereo: we do it before mdct.
1067 * No need to optimize this case because it should almost never
1070 if (!s->channel_coded[0]) {
1071 PARA_NOTICE_LOG("rare ms-stereo\n");
1072 memset(s->coefs[0], 0, sizeof(float) * s->block_len);
1073 s->channel_coded[0] = 1;
1075 for (i = 0; i < s->block_len; i++) {
1078 s->coefs[0][i] = a + b;
1079 s->coefs[1][i] = a - b;
1084 for (ch = 0; ch < s->ahi.channels; ch++) {
1088 n4 = s->block_len / 2;
1089 if (s->channel_coded[ch])
1090 imdct(s->mdct_ctx[bsize], s->output, s->coefs[ch]);
1091 else if (!(s->ms_stereo && ch == 1))
1092 memset(s->output, 0, sizeof(s->output));
1094 /* multiply by the window and add in the frame */
1095 index = (s->frame_len / 2) + s->block_pos - n4;
1096 wma_window(s, &s->frame_out[ch][index]);
1099 /* update block number */
1100 s->block_pos += s->block_len;
1101 if (s->block_pos >= s->frame_len)
1108 * Clip a signed integer value into the -32768,32767 range.
1110 * \param a The value to clip.
1112 * \return The clipped value.
1114 static inline int16_t av_clip_int16(int a)
1116 if ((a + 32768) & ~65535)
1117 return (a >> 31) ^ 32767;
1122 /* Decode a frame of frame_len samples. */
1123 static int wma_decode_frame(struct private_wmadec_data *s, int16_t * samples)
1125 int ret, i, n, ch, incr;
1129 /* read each block */
1132 ret = wma_decode_block(s);
1139 /* convert frame to integer */
1141 incr = s->ahi.channels;
1142 for (ch = 0; ch < s->ahi.channels; ch++) {
1144 iptr = s->frame_out[ch];
1146 for (i = 0; i < n; i++) {
1147 *ptr = av_clip_int16(lrintf(*iptr++));
1150 /* prepare for next block */
1151 memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
1152 s->frame_len * sizeof(float));
1157 static int wma_decode_superframe(struct private_wmadec_data *s, void *data,
1158 int *data_size, const uint8_t *buf, int buf_size)
1160 int ret, nb_frames, bit_offset, i, pos, len;
1163 static int frame_count;
1165 if (buf_size == 0) {
1166 s->last_superframe_len = 0;
1169 if (buf_size < s->ahi.block_align)
1171 buf_size = s->ahi.block_align;
1173 init_get_bits(&s->gb, buf, buf_size * 8);
1174 if (s->use_bit_reservoir) {
1175 /* read super frame header */
1176 skip_bits(&s->gb, 4); /* super frame index */
1177 nb_frames = get_bits(&s->gb, 4) - 1;
1178 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1179 ret = -E_WMA_OUTPUT_SPACE;
1180 if ((nb_frames + 1) * s->ahi.channels * s->frame_len
1181 * sizeof(int16_t) > *data_size)
1184 bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
1186 if (s->last_superframe_len > 0) {
1187 /* add bit_offset bits to last frame */
1188 ret = -E_WMA_BAD_SUPERFRAME;
1189 if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
1190 MAX_CODED_SUPERFRAME_SIZE)
1192 q = s->last_superframe + s->last_superframe_len;
1195 *q++ = get_bits(&s->gb, 8);
1199 *q++ = get_bits(&s->gb, len) << (8 - len);
1202 /* XXX: bit_offset bits into last frame */
1203 init_get_bits(&s->gb, s->last_superframe,
1204 MAX_CODED_SUPERFRAME_SIZE * 8);
1205 /* skip unused bits */
1206 if (s->last_bitoffset > 0)
1207 skip_bits(&s->gb, s->last_bitoffset);
1209 * This frame is stored in the last superframe and in
1212 ret = -E_WMA_DECODE;
1213 if (wma_decode_frame(s, samples) < 0)
1216 samples += s->ahi.channels * s->frame_len;
1219 /* read each frame starting from bit_offset */
1220 pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
1221 init_get_bits(&s->gb, buf + (pos >> 3),
1222 (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)) * 8);
1225 skip_bits(&s->gb, len);
1227 s->reset_block_lengths = 1;
1228 for (i = 0; i < nb_frames; i++) {
1229 ret = -E_WMA_DECODE;
1230 if (wma_decode_frame(s, samples) < 0)
1233 samples += s->ahi.channels * s->frame_len;
1236 /* we copy the end of the frame in the last frame buffer */
1237 pos = get_bits_count(&s->gb) +
1238 ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
1239 s->last_bitoffset = pos & 7;
1241 len = buf_size - pos;
1242 ret = -E_WMA_BAD_SUPERFRAME;
1243 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
1246 s->last_superframe_len = len;
1247 memcpy(s->last_superframe, buf + pos, len);
1249 PARA_DEBUG_LOG("not using bit reservoir\n");
1250 ret = -E_WMA_OUTPUT_SPACE;
1251 if (s->ahi.channels * s->frame_len * sizeof(int16_t) > *data_size)
1253 /* single frame decode */
1254 ret = -E_WMA_DECODE;
1255 if (wma_decode_frame(s, samples) < 0)
1258 samples += s->ahi.channels * s->frame_len;
1260 PARA_DEBUG_LOG("frame_count: %d frame_len: %d, block_len: %d, "
1261 "outbytes: %d, eaten: %d\n",
1262 frame_count, s->frame_len, s->block_len,
1263 (int8_t *) samples - (int8_t *) data, s->ahi.block_align);
1264 *data_size = (int8_t *)samples - (int8_t *)data;
1265 return s->ahi.block_align;
1267 /* reset the bit reservoir on errors */
1268 s->last_superframe_len = 0;
1272 static ssize_t wmadec_convert(char *inbuffer, size_t len,
1273 struct filter_node *fn)
1275 int ret, out_size = fn->bufsize - fn->loaded;
1276 struct private_wmadec_data *pwd = fn->private_data;
1278 if (out_size < 128 * 1024)
1281 ret = wma_decode_init(inbuffer, len, &pwd);
1284 fn->private_data = pwd;
1285 fn->fc->channels = pwd->ahi.channels;
1286 fn->fc->samplerate = pwd->ahi.sample_rate;
1287 return pwd->ahi.header_len;
1290 if (len <= WMA_FRAME_SKIP + pwd->ahi.block_align)
1292 ret = wma_decode_superframe(pwd, fn->buf + fn->loaded,
1293 &out_size, (uint8_t *)inbuffer + WMA_FRAME_SKIP,
1294 len - WMA_FRAME_SKIP);
1297 fn->loaded += out_size;
1298 return ret + WMA_FRAME_SKIP;
1301 static void wmadec_close(struct filter_node *fn)
1303 struct private_wmadec_data *pwd = fn->private_data;
1306 wmadec_cleanup(pwd);
1309 free(fn->private_data);
1310 fn->private_data = NULL;
1313 static void wmadec_open(struct filter_node *fn)
1315 fn->bufsize = 1024 * 1024;
1316 fn->buf = para_malloc(fn->bufsize);
1317 fn->private_data = NULL;
1322 * The init function of the wma decoder.
1324 * \param f Its fields are filled in by the function.
1326 void wmadec_filter_init(struct filter *f)
1328 f->open = wmadec_open;
1329 f->close = wmadec_close;
1330 f->convert = wmadec_convert;