2 * WMA compatible decoder
3 * Copyright (c) 2002 The FFmpeg Project.
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * WMA compatible decoder.
23 * This decoder handles Microsoft Windows Media Audio data, versions 1 & 2.
24 * WMA v1 is identified by audio format 0x160 in Microsoft media files
25 * (ASF/AVI/WAV). WMA v2 is identified by audio format 0x161.
27 * To use this decoder, a calling application must supply the extra data
28 * bytes provided with the WMA data. These are the extra, codec-specific
29 * bytes at the end of a WAVEFORMATEX data structure. Transmit these bytes
30 * to the decoder using the extradata[_size] fields in AVCodecContext. There
31 * should be 4 extra bytes for v1 data and 6 extra bytes for v2 data.
38 #define BLOCK_MIN_BITS 7
39 #define BLOCK_MAX_BITS 11
40 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
42 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
44 /* XXX: find exact max size */
45 #define HIGH_BAND_MAX_SIZE 16
47 #define NB_LSP_COEFS 10
49 /* XXX: is it a suitable value ? */
50 #define MAX_CODED_SUPERFRAME_SIZE 4096
52 #define MAX_CHANNELS 2
54 #define NOISE_TAB_SIZE 8192
56 #define LSP_POW_BITS 7
58 typedef struct WMADecodeContext {
63 int version; /* 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2) */
65 int use_bit_reservoir;
66 int use_variable_block_len;
67 int use_exp_vlc; /* exponent coding: 0 = lsp, 1 = vlc + delta */
68 int use_noise_coding; /* true if perceptual noise is added */
71 int exponent_sizes[BLOCK_NB_SIZES];
72 uint16_t exponent_bands[BLOCK_NB_SIZES][25];
73 int high_band_start[BLOCK_NB_SIZES]; /* index of first coef in high band */
74 int coefs_start; /* first coded coef */
75 int coefs_end[BLOCK_NB_SIZES]; /* max number of coded coefficients */
76 int exponent_high_sizes[BLOCK_NB_SIZES];
77 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
80 /* coded values in high bands */
81 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
82 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
84 /* there are two possible tables for spectral coefficients */
86 uint16_t *run_table[2];
87 uint16_t *level_table[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_num; /* block number in current frame */
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 float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE] __attribute__((aligned(16)));
103 float max_exponent[MAX_CHANNELS];
104 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
105 float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE] __attribute__((aligned(16)));
106 MDCTContext mdct_ctx[BLOCK_NB_SIZES];
107 float *windows[BLOCK_NB_SIZES];
108 FFTSample mdct_tmp[BLOCK_MAX_SIZE] __attribute__((aligned(16))); /* temporary storage for imdct */
109 /* output buffer for one frame and the last for IMDCT windowing */
110 float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2] __attribute__((aligned(16)));
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)];
129 typedef struct CoefVLCTable {
130 int n; /* total number of codes */
131 const uint32_t *huffcodes; /* VLC bit values */
132 const uint8_t *huffbits; /* VLC bit size */
133 const uint16_t *levels; /* table to build run/level tables */
136 static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len);
141 static void dump_shorts(const char *name, const short *tab, int n)
145 tprintf("%s[%d]:\n", name, n);
149 tprintf(" %5d.0", tab[i]);
155 static void dump_floats(const char *name, int prec, const float *tab, int n)
159 tprintf("%s[%d]:\n", name, n);
163 tprintf(" %8.*f", prec, tab[i]);
172 /* XXX: use same run/length optimization as mpeg decoders */
173 static void init_coef_vlc(VLC *vlc,
174 uint16_t **prun_table, uint16_t **plevel_table,
175 const CoefVLCTable *vlc_table)
177 int n = vlc_table->n;
178 const uint8_t *table_bits = vlc_table->huffbits;
179 const uint32_t *table_codes = vlc_table->huffcodes;
180 const uint16_t *levels_table = vlc_table->levels;
181 uint16_t *run_table, *level_table;
185 init_vlc(vlc, 9, n, table_bits, 1, 1, table_codes, 4, 4);
187 run_table = av_malloc(n * sizeof(uint16_t));
188 level_table = av_malloc(n * sizeof(uint16_t));
196 level_table[i] = level;
201 *prun_table = run_table;
202 *plevel_table = level_table;
205 static int wma_decode_init(AVCodecContext * avctx)
207 WMADecodeContext *s = avctx->priv_data;
208 int i, flags1, flags2;
211 float bps1, high_freq, bps;
215 s->sample_rate = avctx->sample_rate;
216 s->nb_channels = avctx->channels;
217 s->bit_rate = avctx->bit_rate;
218 s->block_align = avctx->block_align;
220 if (avctx->codec->id == CODEC_ID_WMAV1) {
226 /* extract flag infos */
229 extradata = avctx->extradata;
230 if (s->version == 1 && avctx->extradata_size >= 4) {
231 flags1 = extradata[0] | (extradata[1] << 8);
232 flags2 = extradata[2] | (extradata[3] << 8);
233 } else if (s->version == 2 && avctx->extradata_size >= 6) {
234 flags1 = extradata[0] | (extradata[1] << 8) |
235 (extradata[2] << 16) | (extradata[3] << 24);
236 flags2 = extradata[4] | (extradata[5] << 8);
238 s->use_exp_vlc = flags2 & 0x0001;
239 s->use_bit_reservoir = flags2 & 0x0002;
240 s->use_variable_block_len = flags2 & 0x0004;
242 /* compute MDCT block size */
243 if (s->sample_rate <= 16000) {
244 s->frame_len_bits = 9;
245 } else if (s->sample_rate <= 22050 ||
246 (s->sample_rate <= 32000 && s->version == 1)) {
247 s->frame_len_bits = 10;
249 s->frame_len_bits = 11;
251 s->frame_len = 1 << s->frame_len_bits;
252 if (s->use_variable_block_len) {
254 nb = ((flags2 >> 3) & 3) + 1;
255 if ((s->bit_rate / s->nb_channels) >= 32000)
257 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
260 s->nb_block_sizes = nb + 1;
262 s->nb_block_sizes = 1;
265 /* init rate dependant parameters */
266 s->use_noise_coding = 1;
267 high_freq = s->sample_rate * 0.5;
269 /* if version 2, then the rates are normalized */
270 sample_rate1 = s->sample_rate;
271 if (s->version == 2) {
272 if (sample_rate1 >= 44100)
273 sample_rate1 = 44100;
274 else if (sample_rate1 >= 22050)
275 sample_rate1 = 22050;
276 else if (sample_rate1 >= 16000)
277 sample_rate1 = 16000;
278 else if (sample_rate1 >= 11025)
279 sample_rate1 = 11025;
280 else if (sample_rate1 >= 8000)
284 bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
285 s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0)) + 2;
287 /* compute high frequency value and choose if noise coding should
290 if (s->nb_channels == 2)
292 if (sample_rate1 == 44100) {
294 s->use_noise_coding = 0;
296 high_freq = high_freq * 0.4;
297 } else if (sample_rate1 == 22050) {
299 s->use_noise_coding = 0;
300 else if (bps1 >= 0.72)
301 high_freq = high_freq * 0.7;
303 high_freq = high_freq * 0.6;
304 } else if (sample_rate1 == 16000) {
306 high_freq = high_freq * 0.5;
308 high_freq = high_freq * 0.3;
309 } else if (sample_rate1 == 11025) {
310 high_freq = high_freq * 0.7;
311 } else if (sample_rate1 == 8000) {
313 high_freq = high_freq * 0.5;
314 } else if (bps > 0.75) {
315 s->use_noise_coding = 0;
317 high_freq = high_freq * 0.65;
321 high_freq = high_freq * 0.75;
322 } else if (bps >= 0.6) {
323 high_freq = high_freq * 0.6;
325 high_freq = high_freq * 0.5;
328 dprintf("flags1=0x%x flags2=0x%x\n", flags1, flags2);
329 dprintf("version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
330 s->version, s->nb_channels, s->sample_rate, s->bit_rate,
332 dprintf("bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
333 bps, bps1, high_freq, s->byte_offset_bits);
334 dprintf("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
335 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
337 /* compute the scale factor band sizes for each MDCT block size */
339 int a, b, pos, lpos, k, block_len, i, j, n;
340 const uint8_t *table;
342 if (s->version == 1) {
347 for(k = 0; k < s->nb_block_sizes; k++) {
348 block_len = s->frame_len >> k;
350 if (s->version == 1) {
353 a = wma_critical_freqs[i];
355 pos = ((block_len * 2 * a) + (b >> 1)) / b;
358 s->exponent_bands[0][i] = pos - lpos;
359 if (pos >= block_len) {
365 s->exponent_sizes[0] = i;
367 /* hardcoded tables */
369 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
371 if (s->sample_rate >= 44100)
372 table = exponent_band_44100[a];
373 else if (s->sample_rate >= 32000)
374 table = exponent_band_32000[a];
375 else if (s->sample_rate >= 22050)
376 table = exponent_band_22050[a];
381 s->exponent_bands[k][i] = table[i];
382 s->exponent_sizes[k] = n;
387 a = wma_critical_freqs[i];
389 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
394 s->exponent_bands[k][j++] = pos - lpos;
395 if (pos >= block_len)
399 s->exponent_sizes[k] = j;
403 /* max number of coefs */
404 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
405 /* high freq computation */
406 s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
407 s->sample_rate + 0.5);
408 n = s->exponent_sizes[k];
414 pos += s->exponent_bands[k][i];
416 if (start < s->high_band_start[k])
417 start = s->high_band_start[k];
418 if (end > s->coefs_end[k])
419 end = s->coefs_end[k];
421 s->exponent_high_bands[k][j++] = end - start;
423 s->exponent_high_sizes[k] = j;
425 tprintf("%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
428 s->high_band_start[k],
429 s->exponent_high_sizes[k]);
430 for(j=0;j<s->exponent_high_sizes[k];j++)
431 tprintf(" %d", s->exponent_high_bands[k][j]);
440 for(i = 0; i < s->nb_block_sizes; i++) {
441 tprintf("%5d: n=%2d:",
443 s->exponent_sizes[i]);
444 for(j=0;j<s->exponent_sizes[i];j++)
445 tprintf(" %d", s->exponent_bands[i][j]);
452 for(i = 0; i < s->nb_block_sizes; i++)
453 ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1);
455 /* init MDCT windows : simple sinus window */
456 for(i = 0; i < s->nb_block_sizes; i++) {
459 n = 1 << (s->frame_len_bits - i);
460 window = av_malloc(sizeof(float) * n);
461 alpha = M_PI / (2.0 * n);
463 window[n - j - 1] = sin((j + 0.5) * alpha);
465 s->windows[i] = window;
468 s->reset_block_lengths = 1;
470 if (s->use_noise_coding) {
472 /* init the noise generator */
474 s->noise_mult = 0.02;
476 s->noise_mult = 0.04;
479 for(i=0;i<NOISE_TAB_SIZE;i++)
480 s->noise_table[i] = 1.0 * s->noise_mult;
486 norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
487 for(i=0;i<NOISE_TAB_SIZE;i++) {
488 seed = seed * 314159 + 1;
489 s->noise_table[i] = (float)((int)seed) * norm;
493 init_vlc(&s->hgain_vlc, 9, sizeof(hgain_huffbits),
494 hgain_huffbits, 1, 1,
495 hgain_huffcodes, 2, 2);
498 if (s->use_exp_vlc) {
499 init_vlc(&s->exp_vlc, 9, sizeof(scale_huffbits),
500 scale_huffbits, 1, 1,
501 scale_huffcodes, 4, 4);
503 wma_lsp_to_curve_init(s, s->frame_len);
506 /* choose the VLC tables for the coefficients */
508 if (s->sample_rate >= 32000) {
511 else if (bps1 < 1.16)
515 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
516 &coef_vlcs[coef_vlc_table * 2]);
517 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
518 &coef_vlcs[coef_vlc_table * 2 + 1]);
522 /* interpolate values for a bigger or smaller block. The block must
523 have multiple sizes */
524 static void interpolate_array(float *scale, int old_size, int new_size)
529 if (new_size > old_size) {
530 jincr = new_size / old_size;
532 for(i = old_size - 1; i >=0; i--) {
539 } else if (new_size < old_size) {
541 jincr = old_size / new_size;
542 for(i = 0; i < new_size; i++) {
549 /* compute x^-0.25 with an exponent and mantissa table. We use linear
550 interpolation to reduce the mantissa table size at a small speed
551 expense (linear interpolation approximately doubles the number of
552 bits of precision). */
553 static inline float pow_m1_4(WMADecodeContext *s, float x)
564 m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
565 /* build interpolation scale: 1 <= t < 2. */
566 t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
567 a = s->lsp_pow_m_table1[m];
568 b = s->lsp_pow_m_table2[m];
569 return s->lsp_pow_e_table[e] * (a + b * t.f);
572 static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len)
577 wdel = M_PI / frame_len;
578 for(i=0;i<frame_len;i++)
579 s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
581 /* tables for x^-0.25 computation */
584 s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
587 /* NOTE: these two tables are needed to avoid two operations in
590 for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
591 m = (1 << LSP_POW_BITS) + i;
592 a = (float)m * (0.5 / (1 << LSP_POW_BITS));
594 s->lsp_pow_m_table1[i] = 2 * a - b;
595 s->lsp_pow_m_table2[i] = b - a;
604 printf("%f^-0.25=%f e=%f\n", v, r1, r2 - r1);
609 /* NOTE: We use the same code as Vorbis here */
610 /* XXX: optimize it further with SSE/3Dnow */
611 static void wma_lsp_to_curve(WMADecodeContext *s,
612 float *out, float *val_max_ptr,
616 float p, q, w, v, val_max;
622 w = s->lsp_cos_table[i];
623 for(j=1;j<NB_LSP_COEFS;j+=2){
635 *val_max_ptr = val_max;
638 /* decode exponents coded with LSP coefficients (same idea as Vorbis) */
639 static void decode_exp_lsp(WMADecodeContext *s, int ch)
641 float lsp_coefs[NB_LSP_COEFS];
644 for(i = 0; i < NB_LSP_COEFS; i++) {
645 if (i == 0 || i >= 8)
646 val = get_bits(&s->gb, 3);
648 val = get_bits(&s->gb, 4);
649 lsp_coefs[i] = lsp_codebook[i][val];
652 wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
653 s->block_len, lsp_coefs);
656 /* decode exponents coded with VLC codes */
657 static int decode_exp_vlc(WMADecodeContext *s, int ch)
659 int last_exp, n, code;
660 const uint16_t *ptr, *band_ptr;
661 float v, *q, max_scale, *q_end;
663 band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
665 q = s->exponents[ch];
666 q_end = q + s->block_len;
668 if (s->version == 1) {
669 last_exp = get_bits(&s->gb, 5) + 10;
670 /* XXX: use a table */
671 v = pow(10, last_exp * (1.0 / 16.0));
680 code = get_vlc(&s->gb, &s->exp_vlc);
683 /* NOTE: this offset is the same as MPEG4 AAC ! */
684 last_exp += code - 60;
685 /* XXX: use a table */
686 v = pow(10, last_exp * (1.0 / 16.0));
694 s->max_exponent[ch] = max_scale;
698 /* return 0 if OK. return 1 if last block of frame. return -1 if
699 unrecorrable error. */
700 static int wma_decode_block(WMADecodeContext *s)
702 int n, v, a, ch, code, bsize;
703 int coef_nb_bits, total_gain, parse_exponents;
704 float window[BLOCK_MAX_SIZE * 2];
705 int nb_coefs[MAX_CHANNELS];
709 tprintf("***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
712 /* compute current block length */
713 if (s->use_variable_block_len) {
714 n = av_log2(s->nb_block_sizes - 1) + 1;
716 if (s->reset_block_lengths) {
717 s->reset_block_lengths = 0;
718 v = get_bits(&s->gb, n);
719 if (v >= s->nb_block_sizes)
721 s->prev_block_len_bits = s->frame_len_bits - v;
722 v = get_bits(&s->gb, n);
723 if (v >= s->nb_block_sizes)
725 s->block_len_bits = s->frame_len_bits - v;
727 /* update block lengths */
728 s->prev_block_len_bits = s->block_len_bits;
729 s->block_len_bits = s->next_block_len_bits;
731 v = get_bits(&s->gb, n);
732 if (v >= s->nb_block_sizes)
734 s->next_block_len_bits = s->frame_len_bits - v;
736 /* fixed block len */
737 s->next_block_len_bits = s->frame_len_bits;
738 s->prev_block_len_bits = s->frame_len_bits;
739 s->block_len_bits = s->frame_len_bits;
742 /* now check if the block length is coherent with the frame length */
743 s->block_len = 1 << s->block_len_bits;
744 if ((s->block_pos + s->block_len) > s->frame_len)
747 if (s->nb_channels == 2) {
748 s->ms_stereo = get_bits(&s->gb, 1);
751 for(ch = 0; ch < s->nb_channels; ch++) {
752 a = get_bits(&s->gb, 1);
753 s->channel_coded[ch] = a;
756 /* if no channel coded, no need to go further */
757 /* XXX: fix potential framing problems */
761 bsize = s->frame_len_bits - s->block_len_bits;
763 /* read total gain and extract corresponding number of bits for
764 coef escape coding */
767 a = get_bits(&s->gb, 7);
775 else if (total_gain < 32)
777 else if (total_gain < 40)
779 else if (total_gain < 45)
784 /* compute number of coefficients */
785 n = s->coefs_end[bsize] - s->coefs_start;
786 for(ch = 0; ch < s->nb_channels; ch++)
790 if (s->use_noise_coding) {
792 for(ch = 0; ch < s->nb_channels; ch++) {
793 if (s->channel_coded[ch]) {
795 n = s->exponent_high_sizes[bsize];
797 a = get_bits(&s->gb, 1);
798 s->high_band_coded[ch][i] = a;
799 /* if noise coding, the coefficients are not transmitted */
801 nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
805 for(ch = 0; ch < s->nb_channels; ch++) {
806 if (s->channel_coded[ch]) {
809 n = s->exponent_high_sizes[bsize];
810 val = (int)0x80000000;
812 if (s->high_band_coded[ch][i]) {
813 if (val == (int)0x80000000) {
814 val = get_bits(&s->gb, 7) - 19;
816 code = get_vlc(&s->gb, &s->hgain_vlc);
821 s->high_band_values[ch][i] = val;
828 /* exposant can be interpolated in short blocks. */
830 if (s->block_len_bits != s->frame_len_bits) {
831 parse_exponents = get_bits(&s->gb, 1);
834 if (parse_exponents) {
835 for(ch = 0; ch < s->nb_channels; ch++) {
836 if (s->channel_coded[ch]) {
837 if (s->use_exp_vlc) {
838 if (decode_exp_vlc(s, ch) < 0)
841 decode_exp_lsp(s, ch);
846 for(ch = 0; ch < s->nb_channels; ch++) {
847 if (s->channel_coded[ch]) {
848 interpolate_array(s->exponents[ch], 1 << s->prev_block_len_bits,
854 /* parse spectral coefficients : just RLE encoding */
855 for(ch = 0; ch < s->nb_channels; ch++) {
856 if (s->channel_coded[ch]) {
858 int level, run, sign, tindex;
860 const int16_t *level_table, *run_table;
862 /* special VLC tables are used for ms stereo because
863 there is potentially less energy there */
864 tindex = (ch == 1 && s->ms_stereo);
865 coef_vlc = &s->coef_vlc[tindex];
866 run_table = s->run_table[tindex];
867 level_table = s->level_table[tindex];
869 ptr = &s->coefs1[ch][0];
870 eptr = ptr + nb_coefs[ch];
871 memset(ptr, 0, s->block_len * sizeof(int16_t));
873 code = get_vlc(&s->gb, coef_vlc);
879 } else if (code == 0) {
881 level = get_bits(&s->gb, coef_nb_bits);
882 /* NOTE: this is rather suboptimal. reading
883 block_len_bits would be better */
884 run = get_bits(&s->gb, s->frame_len_bits);
887 run = run_table[code];
888 level = level_table[code];
890 sign = get_bits(&s->gb, 1);
897 /* NOTE: EOB can be omitted */
902 if (s->version == 1 && s->nb_channels >= 2) {
903 align_get_bits(&s->gb);
909 int n4 = s->block_len / 2;
910 mdct_norm = 1.0 / (float)n4;
911 if (s->version == 1) {
912 mdct_norm *= sqrt(n4);
916 /* finally compute the MDCT coefficients */
917 for(ch = 0; ch < s->nb_channels; ch++) {
918 if (s->channel_coded[ch]) {
920 float *coefs, *exponents, mult, mult1, noise, *exp_ptr;
921 int i, j, n, n1, last_high_band;
922 float exp_power[HIGH_BAND_MAX_SIZE];
924 coefs1 = s->coefs1[ch];
925 exponents = s->exponents[ch];
926 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
928 coefs = s->coefs[ch];
929 if (s->use_noise_coding) {
931 /* very low freqs : noise */
932 for(i = 0;i < s->coefs_start; i++) {
933 *coefs++ = s->noise_table[s->noise_index] * (*exponents++) * mult1;
934 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
937 n1 = s->exponent_high_sizes[bsize];
939 /* compute power of high bands */
940 exp_ptr = exponents +
941 s->high_band_start[bsize] -
943 last_high_band = 0; /* avoid warning */
945 n = s->exponent_high_bands[s->frame_len_bits -
946 s->block_len_bits][j];
947 if (s->high_band_coded[ch][j]) {
950 for(i = 0;i < n; i++) {
954 exp_power[j] = e2 / n;
956 tprintf("%d: power=%f (%d)\n", j, exp_power[j], n);
961 /* main freqs and high freqs */
964 n = s->high_band_start[bsize] -
967 n = s->exponent_high_bands[s->frame_len_bits -
968 s->block_len_bits][j];
970 if (j >= 0 && s->high_band_coded[ch][j]) {
971 /* use noise with specified power */
972 mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
973 /* XXX: use a table */
974 mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
975 mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
977 for(i = 0;i < n; i++) {
978 noise = s->noise_table[s->noise_index];
979 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
980 *coefs++ = (*exponents++) * noise * mult1;
983 /* coded values + small noise */
984 for(i = 0;i < n; i++) {
985 noise = s->noise_table[s->noise_index];
986 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
987 *coefs++ = ((*coefs1++) + noise) * (*exponents++) * mult;
992 /* very high freqs : noise */
993 n = s->block_len - s->coefs_end[bsize];
994 mult1 = mult * exponents[-1];
995 for(i = 0; i < n; i++) {
996 *coefs++ = s->noise_table[s->noise_index] * mult1;
997 s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
1000 /* XXX: optimize more */
1001 for(i = 0;i < s->coefs_start; i++)
1004 for(i = 0;i < n; i++) {
1005 *coefs++ = coefs1[i] * exponents[i] * mult;
1007 n = s->block_len - s->coefs_end[bsize];
1008 for(i = 0;i < n; i++)
1015 for(ch = 0; ch < s->nb_channels; ch++) {
1016 if (s->channel_coded[ch]) {
1017 dump_floats("exponents", 3, s->exponents[ch], s->block_len);
1018 dump_floats("coefs", 1, s->coefs[ch], s->block_len);
1023 if (s->ms_stereo && s->channel_coded[1]) {
1027 /* nominal case for ms stereo: we do it before mdct */
1028 /* no need to optimize this case because it should almost
1030 if (!s->channel_coded[0]) {
1031 tprintf("rare ms-stereo case happened\n");
1032 memset(s->coefs[0], 0, sizeof(float) * s->block_len);
1033 s->channel_coded[0] = 1;
1036 for(i = 0; i < s->block_len; i++) {
1039 s->coefs[0][i] = a + b;
1040 s->coefs[1][i] = a - b;
1044 /* build the window : we ensure that when the windows overlap
1045 their squared sum is always 1 (MDCT reconstruction rule) */
1046 /* XXX: merge with output */
1048 int i, next_block_len, block_len, prev_block_len, n;
1051 block_len = s->block_len;
1052 prev_block_len = 1 << s->prev_block_len_bits;
1053 next_block_len = 1 << s->next_block_len_bits;
1056 wptr = window + block_len;
1057 if (block_len <= next_block_len) {
1058 for(i=0;i<block_len;i++)
1059 *wptr++ = s->windows[bsize][i];
1062 n = (block_len / 2) - (next_block_len / 2);
1065 for(i=0;i<next_block_len;i++)
1066 *wptr++ = s->windows[s->frame_len_bits - s->next_block_len_bits][i];
1072 wptr = window + block_len;
1073 if (block_len <= prev_block_len) {
1074 for(i=0;i<block_len;i++)
1075 *--wptr = s->windows[bsize][i];
1078 n = (block_len / 2) - (prev_block_len / 2);
1081 for(i=0;i<prev_block_len;i++)
1082 *--wptr = s->windows[s->frame_len_bits - s->prev_block_len_bits][i];
1089 for(ch = 0; ch < s->nb_channels; ch++) {
1090 if (s->channel_coded[ch]) {
1091 FFTSample output[BLOCK_MAX_SIZE * 2] __attribute__((aligned(16)));
1093 int i, n4, index, n;
1096 n4 = s->block_len / 2;
1097 ff_imdct_calc(&s->mdct_ctx[bsize],
1098 output, s->coefs[ch], s->mdct_tmp);
1100 /* XXX: optimize all that by build the window and
1101 multipying/adding at the same time */
1102 /* multiply by the window */
1103 for(i=0;i<n * 2;i++) {
1104 output[i] *= window[i];
1107 /* add in the frame */
1108 index = (s->frame_len / 2) + s->block_pos - n4;
1109 ptr = &s->frame_out[ch][index];
1110 for(i=0;i<n * 2;i++) {
1115 /* specific fast case for ms-stereo : add to second
1116 channel if it is not coded */
1117 if (s->ms_stereo && !s->channel_coded[1]) {
1118 ptr = &s->frame_out[1][index];
1119 for(i=0;i<n * 2;i++) {
1127 /* update block number */
1129 s->block_pos += s->block_len;
1130 if (s->block_pos >= s->frame_len)
1136 /* decode a frame of frame_len samples */
1137 static int wma_decode_frame(WMADecodeContext *s, int16_t *samples)
1139 int ret, i, n, a, ch, incr;
1144 tprintf("***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
1147 /* read each block */
1151 ret = wma_decode_block(s);
1158 /* convert frame to integer */
1160 incr = s->nb_channels;
1161 for(ch = 0; ch < s->nb_channels; ch++) {
1163 iptr = s->frame_out[ch];
1166 a = lrintf(*iptr++);
1169 else if (a < -32768)
1174 /* prepare for next block */
1175 memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
1176 s->frame_len * sizeof(float));
1177 /* XXX: suppress this */
1178 memset(&s->frame_out[ch][s->frame_len], 0,
1179 s->frame_len * sizeof(float));
1183 dump_shorts("samples", samples, n * s->nb_channels);
1188 static int wma_decode_superframe(AVCodecContext *avctx,
1189 void *data, int *data_size,
1190 uint8_t *buf, int buf_size)
1192 WMADecodeContext *s = avctx->priv_data;
1193 int nb_frames, bit_offset, i, pos, len;
1197 tprintf("***decode_superframe:\n");
1200 s->last_superframe_len = 0;
1206 init_get_bits(&s->gb, buf, buf_size*8);
1208 if (s->use_bit_reservoir) {
1209 /* read super frame header */
1210 get_bits(&s->gb, 4); /* super frame index */
1211 nb_frames = get_bits(&s->gb, 4) - 1;
1213 bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
1215 if (s->last_superframe_len > 0) {
1216 // printf("skip=%d\n", s->last_bitoffset);
1217 /* add bit_offset bits to last frame */
1218 if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
1219 MAX_CODED_SUPERFRAME_SIZE)
1221 q = s->last_superframe + s->last_superframe_len;
1224 *q++ = (get_bits)(&s->gb, 8);
1228 *q++ = (get_bits)(&s->gb, len) << (8 - len);
1231 /* XXX: bit_offset bits into last frame */
1232 init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8);
1233 /* skip unused bits */
1234 if (s->last_bitoffset > 0)
1235 skip_bits(&s->gb, s->last_bitoffset);
1236 /* this frame is stored in the last superframe and in the
1238 if (wma_decode_frame(s, samples) < 0)
1240 samples += s->nb_channels * s->frame_len;
1243 /* read each frame starting from bit_offset */
1244 pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
1245 init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8);
1248 skip_bits(&s->gb, len);
1250 s->reset_block_lengths = 1;
1251 for(i=0;i<nb_frames;i++) {
1252 if (wma_decode_frame(s, samples) < 0)
1254 samples += s->nb_channels * s->frame_len;
1257 /* we copy the end of the frame in the last frame buffer */
1258 pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
1259 s->last_bitoffset = pos & 7;
1261 len = buf_size - pos;
1262 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
1265 s->last_superframe_len = len;
1266 memcpy(s->last_superframe, buf + pos, len);
1268 /* single frame decode */
1269 if (wma_decode_frame(s, samples) < 0)
1271 samples += s->nb_channels * s->frame_len;
1273 *data_size = (int8_t *)samples - (int8_t *)data;
1274 return s->block_align;
1276 /* when error, we reset the bit reservoir */
1277 s->last_superframe_len = 0;
1281 static int wma_decode_end(AVCodecContext *avctx)
1283 WMADecodeContext *s = avctx->priv_data;
1286 for(i = 0; i < s->nb_block_sizes; i++)
1287 ff_mdct_end(&s->mdct_ctx[i]);
1288 for(i = 0; i < s->nb_block_sizes; i++)
1289 av_free(s->windows[i]);
1291 if (s->use_exp_vlc) {
1292 free_vlc(&s->exp_vlc);
1294 if (s->use_noise_coding) {
1295 free_vlc(&s->hgain_vlc);
1297 for(i = 0;i < 2; i++) {
1298 free_vlc(&s->coef_vlc[i]);
1299 av_free(s->run_table[i]);
1300 av_free(s->level_table[i]);
1306 AVCodec wmav1_decoder =
1311 sizeof(WMADecodeContext),
1315 wma_decode_superframe,
1318 AVCodec wmav2_decoder =
1323 sizeof(WMADecodeContext),
1327 wma_decode_superframe,