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1
/*
2
 * WMA compatible decoder
3
 * Copyright (c) 2002 The FFmpeg Project.
4
 *
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
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * 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.
14
 *
15
 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 */
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#include "avcodec.h"
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#include "dsputil.h"
21

    
22
//#define DEBUG_PARAMS
23
//#define DEBUG_TRACE
24

    
25
/* size of blocks */
26
#define BLOCK_MIN_BITS 7
27
#define BLOCK_MAX_BITS 11
28
#define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
29

    
30
#define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
31

    
32
/* XXX: find exact max size */
33
#define HIGH_BAND_MAX_SIZE 16
34

    
35
#define NB_LSP_COEFS 10
36

    
37
/* XXX: is it a suitable value ? */
38
#define MAX_CODED_SUPERFRAME_SIZE 4096
39

    
40
#define MAX_CHANNELS 2
41

    
42
#define NOISE_TAB_SIZE 8192
43

    
44
#define LSP_POW_BITS 7
45

    
46
typedef struct WMADecodeContext {
47
    GetBitContext gb;
48
    int sample_rate;
49
    int nb_channels;
50
    int bit_rate;
51
    int version; /* 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2) */
52
    int block_align;
53
    int use_bit_reservoir;
54
    int use_variable_block_len;
55
    int use_exp_vlc;  /* exponent coding: 0 = lsp, 1 = vlc + delta */
56
    int use_noise_coding; /* true if perceptual noise is added */
57
    int byte_offset_bits;
58
    VLC exp_vlc;
59
    int exponent_sizes[BLOCK_NB_SIZES];
60
    uint16_t exponent_bands[BLOCK_NB_SIZES][25];
61
    int high_band_start[BLOCK_NB_SIZES]; /* index of first coef in high band */
62
    int coefs_start;               /* first coded coef */
63
    int coefs_end[BLOCK_NB_SIZES]; /* max number of coded coefficients */
64
    int exponent_high_sizes[BLOCK_NB_SIZES];
65
    int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE]; 
66
    VLC hgain_vlc;
67
    
68
    /* coded values in high bands */
69
    int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
70
    int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
71

    
72
    /* there are two possible tables for spectral coefficients */
73
    VLC coef_vlc[2];
74
    uint16_t *run_table[2];
75
    uint16_t *level_table[2];
76
    /* frame info */
77
    int frame_len;       /* frame length in samples */
78
    int frame_len_bits;  /* frame_len = 1 << frame_len_bits */
79
    int nb_block_sizes;  /* number of block sizes */
80
    /* block info */
81
    int reset_block_lengths;
82
    int block_len_bits; /* log2 of current block length */
83
    int next_block_len_bits; /* log2 of next block length */
84
    int prev_block_len_bits; /* log2 of prev block length */
85
    int block_len; /* block length in samples */
86
    int block_num; /* block number in current frame */
87
    int block_pos; /* current position in frame */
88
    uint8_t ms_stereo; /* true if mid/side stereo mode */
89
    uint8_t channel_coded[MAX_CHANNELS]; /* true if channel is coded */
90
    float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
91
    float max_exponent[MAX_CHANNELS];
92
    int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
93
    float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
94
    MDCTContext mdct_ctx[BLOCK_NB_SIZES];
95
    float *windows[BLOCK_NB_SIZES];
96
    FFTSample mdct_tmp[BLOCK_MAX_SIZE]; /* temporary storage for imdct */
97
    /* output buffer for one frame and the last for IMDCT windowing */
98
    float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
99
    /* last frame info */
100
    uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
101
    int last_bitoffset;
102
    int last_superframe_len;
103
    float noise_table[NOISE_TAB_SIZE];
104
    int noise_index;
105
    float noise_mult; /* XXX: suppress that and integrate it in the noise array */
106
    /* lsp_to_curve tables */
107
    float lsp_cos_table[BLOCK_MAX_SIZE];
108
    float lsp_pow_e_table[256];
109
    float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
110
    float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
111
} WMADecodeContext;
112

    
113
typedef struct CoefVLCTable {
114
    int n; /* total number of codes */
115
    const uint32_t *huffcodes; /* VLC bit values */
116
    const uint8_t *huffbits;   /* VLC bit size */
117
    const uint16_t *levels; /* table to build run/level tables */
118
} CoefVLCTable;
119

    
120
static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len);
121

    
122
#include "wmadata.h"
123

    
124
#ifdef DEBUG_TRACE
125
#include <stdarg.h>
126
int frame_count;
127

    
128
static FILE *flog;
129

    
130
void trace(const char *fmt, ...)
131
{
132
    va_list ap;
133
    
134

    
135
    if (!flog) {
136
        flog = fopen("/tmp/out.log", "w");
137
        setlinebuf(flog);
138
    }
139

    
140
    va_start(ap, fmt);
141
    vfprintf(flog, fmt, ap);
142
    va_end(ap);
143
}
144

    
145
#define get_bits(s, n) get_bits_trace(s, n)
146
#define get_vlc(s, vlc) get_vlc_trace(s, vlc)
147

    
148
unsigned int get_bits_trace(GetBitContext *s, int n)
149
{
150
    unsigned int val;
151
    val = (get_bits)(s, n);
152
    trace("get_bits(%d) : 0x%x\n", n, val);
153
    return val;
154
}
155

    
156
static int get_vlc_trace(GetBitContext *s, VLC *vlc)
157
{
158
    int code;
159
    code = (get_vlc)(s, vlc);
160
    trace("get_vlc() : %d\n", code);
161
    return code;
162
}
163

    
164
static void dump_shorts(const char *name, const short *tab, int n)
165
{
166
    int i;
167

    
168
    trace("%s[%d]:\n", name, n);
169
    for(i=0;i<n;i++) {
170
        if ((i & 7) == 0)
171
            trace("%4d: ", i);
172
        trace(" %5d.0", tab[i]);
173
        if ((i & 7) == 7)
174
            trace("\n");
175
    }
176
}
177

    
178
static void dump_floats(const char *name, int prec, const float *tab, int n)
179
{
180
    int i;
181

    
182
    trace("%s[%d]:\n", name, n);
183
    for(i=0;i<n;i++) {
184
        if ((i & 7) == 0)
185
            trace("%4d: ", i);
186
        trace(" %8.*f", prec, tab[i]);
187
        if ((i & 7) == 7)
188
            trace("\n");
189
    }
190
    if ((i & 7) != 0)
191
        trace("\n");
192
}
193

    
194
#else
195

    
196
#define trace(fmt, ...)
197

    
198
#endif
199

    
200
/* XXX: use same run/length optimization as mpeg decoders */
201
static void init_coef_vlc(VLC *vlc, 
202
                          uint16_t **prun_table, uint16_t **plevel_table,
203
                          const CoefVLCTable *vlc_table)
204
{
205
    int n = vlc_table->n;
206
    const uint8_t *table_bits = vlc_table->huffbits;
207
    const uint32_t *table_codes = vlc_table->huffcodes;
208
    const uint16_t *levels_table = vlc_table->levels;
209
    uint16_t *run_table, *level_table;
210
    const uint16_t *p;
211
    int i, l, j, level;
212

    
213
    init_vlc(vlc, 9, n, table_bits, 1, 1, table_codes, 4, 4);
214

    
215
    run_table = malloc(n * sizeof(uint16_t));
216
    level_table = malloc(n * sizeof(uint16_t));
217
    p = levels_table;
218
    i = 2;
219
    level = 1;
220
    while (i < n) {
221
        l = *p++;
222
        for(j=0;j<l;j++) {
223
            run_table[i] = j;
224
            level_table[i] = level;
225
            i++;
226
        }
227
        level++;
228
    }
229
    *prun_table = run_table;
230
    *plevel_table = level_table;
231
}
232

    
233
static int wma_decode_init(AVCodecContext * avctx)
234
{
235
    WMADecodeContext *s = avctx->priv_data;
236
    int i, flags1, flags2;
237
    float *window;
238
    uint8_t *extradata;
239
    float bps1, high_freq, bps;
240
    int sample_rate1;
241
    int coef_vlc_table;
242
    
243
    s->sample_rate = avctx->sample_rate;
244
    s->nb_channels = avctx->channels;
245
    s->bit_rate = avctx->bit_rate;
246
    s->block_align = avctx->block_align;
247

    
248
    if (avctx->codec->id == CODEC_ID_WMAV1) {
249
        s->version = 1;
250
    } else {
251
        s->version = 2;
252
    }
253
    
254
    /* extract flag infos */
255
    flags1 = 0;
256
    flags2 = 0;
257
    extradata = avctx->extradata;
258
    if (s->version == 1 && avctx->extradata_size >= 4) {
259
        flags1 = extradata[0] | (extradata[1] << 8);
260
        flags2 = extradata[2] | (extradata[3] << 8);
261
    } else if (s->version == 2 && avctx->extradata_size >= 6) {
262
        flags1 = extradata[0] | (extradata[1] << 8) | 
263
            (extradata[2] << 16) | (extradata[3] << 24);
264
        flags2 = extradata[4] | (extradata[5] << 8);
265
    }
266
    s->use_exp_vlc = flags2 & 0x0001;
267
    s->use_bit_reservoir = flags2 & 0x0002;
268
    s->use_variable_block_len = flags2 & 0x0004;
269

    
270
    /* compute MDCT block size */
271
    if (s->sample_rate <= 16000) {
272
        s->frame_len_bits = 9;
273
    } else if (s->sample_rate <= 22050 || 
274
               (s->sample_rate <= 32000 && s->version == 1)) {
275
        s->frame_len_bits = 10;
276
    } else {
277
        s->frame_len_bits = 11;
278
    }
279
    s->frame_len = 1 << s->frame_len_bits;
280
    if (s->use_variable_block_len) {
281
        int nb_max, nb;
282
        nb = ((flags2 >> 3) & 3) + 1;
283
        if ((s->bit_rate / s->nb_channels) >= 32000)
284
            nb += 2;
285
        nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
286
        if (nb > nb_max)
287
            nb = nb_max;
288
        s->nb_block_sizes = nb + 1;
289
    } else {
290
        s->nb_block_sizes = 1;
291
    }
292

    
293
    /* init rate dependant parameters */
294
    s->use_noise_coding = 1;
295
    high_freq = s->sample_rate * 0.5;
296

    
297
    /* if version 2, then the rates are normalized */
298
    sample_rate1 = s->sample_rate;
299
    if (s->version == 2) {
300
        if (sample_rate1 >= 44100) 
301
            sample_rate1 = 44100;
302
        else if (sample_rate1 >= 22050) 
303
            sample_rate1 = 22050;
304
        else if (sample_rate1 >= 16000) 
305
            sample_rate1 = 16000;
306
        else if (sample_rate1 >= 11025) 
307
            sample_rate1 = 11025;
308
        else if (sample_rate1 >= 8000) 
309
            sample_rate1 = 8000;
310
    }
311

    
312
    bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
313
    s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0)) + 2;
314

    
315
    /* compute high frequency value and choose if noise coding should
316
       be activated */
317
    bps1 = bps;
318
    if (s->nb_channels == 2)
319
        bps1 = bps * 1.6;
320
    if (sample_rate1 == 44100) {
321
        if (bps1 >= 0.61)
322
            s->use_noise_coding = 0;
323
        else
324
            high_freq = high_freq * 0.4;
325
    } else if (sample_rate1 == 22050) {
326
        if (bps1 >= 1.16)
327
            s->use_noise_coding = 0;
328
        else if (bps1 >= 0.72) 
329
            high_freq = high_freq * 0.7;
330
        else
331
            high_freq = high_freq * 0.6;
332
    } else if (sample_rate1 == 16000) {
333
        if (bps > 0.5)
334
            high_freq = high_freq * 0.5;
335
        else
336
            high_freq = high_freq * 0.3;
337
    } else if (sample_rate1 == 11025) {
338
        high_freq = high_freq * 0.7;
339
    } else if (sample_rate1 == 8000) {
340
        if (bps <= 0.625) {
341
            high_freq = high_freq * 0.5;
342
        } else if (bps > 0.75) {
343
            s->use_noise_coding = 0;
344
        } else {
345
            high_freq = high_freq * 0.65;
346
        }
347
    } else {
348
        if (bps >= 0.8) {
349
            high_freq = high_freq * 0.75;
350
        } else if (bps >= 0.6) {
351
            high_freq = high_freq * 0.6;
352
        } else {
353
            high_freq = high_freq * 0.5;
354
        }
355
    }
356
#ifdef DEBUG_PARAMS
357
    printf("flags1=0x%x flags2=0x%x\n", flags1, flags2);
358
    printf("version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
359
           s->version, s->nb_channels, s->sample_rate, s->bit_rate, 
360
           s->block_align);
361
    printf("bps=%f bps1=%f high_freq=%f bitoffset=%d\n", 
362
           bps, bps1, high_freq, s->byte_offset_bits);
363
    printf("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
364
           s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
365
#endif
366

    
367
    /* compute the scale factor band sizes for each MDCT block size */
368
    {
369
        int a, b, pos, lpos, k, block_len, i, j, n;
370
        const uint8_t *table;
371
        
372
        if (s->version == 1) {
373
            s->coefs_start = 3;
374
        } else {
375
            s->coefs_start = 0;
376
        }
377
        for(k = 0; k < s->nb_block_sizes; k++) {
378
            block_len = s->frame_len >> k;
379

    
380
            if (s->version == 1) {
381
                lpos = 0;
382
                for(i=0;i<25;i++) {
383
                    a = wma_critical_freqs[i];
384
                    b = s->sample_rate;
385
                    pos = ((block_len * 2 * a)  + (b >> 1)) / b;
386
                    if (pos > block_len) 
387
                        pos = block_len;
388
                    s->exponent_bands[0][i] = pos - lpos;
389
                    if (pos >= block_len) {
390
                        i++;
391
                        break;
392
                    }
393
                    lpos = pos;
394
                }
395
                s->exponent_sizes[0] = i;
396
            } else {
397
                /* hardcoded tables */
398
                table = NULL;
399
                a = s->frame_len_bits - BLOCK_MIN_BITS - k;
400
                if (a < 3) {
401
                    if (s->sample_rate >= 44100)
402
                        table = exponent_band_44100[a];
403
                    else if (s->sample_rate >= 32000)
404
                        table = exponent_band_32000[a];
405
                    else if (s->sample_rate >= 22050)
406
                        table = exponent_band_22050[a];
407
                }
408
                if (table) {
409
                    n = *table++;
410
                    for(i=0;i<n;i++)
411
                        s->exponent_bands[k][i] = table[i];
412
                    s->exponent_sizes[k] = n;
413
                } else {
414
                    j = 0;
415
                    lpos = 0;
416
                    for(i=0;i<25;i++) {
417
                        a = wma_critical_freqs[i];
418
                        b = s->sample_rate;
419
                        pos = ((block_len * 2 * a)  + (b << 1)) / (4 * b);
420
                        pos <<= 2;
421
                        if (pos > block_len) 
422
                            pos = block_len;
423
                        if (pos > lpos)
424
                            s->exponent_bands[k][j++] = pos - lpos;
425
                        if (pos >= block_len)
426
                            break;
427
                        lpos = pos;
428
                    }
429
                    s->exponent_sizes[k] = j;
430
                }
431
            }
432

    
433
            /* max number of coefs */
434
            s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
435
            /* high freq computation */
436
            s->high_band_start[k] = (int)((block_len * 2 * high_freq) / 
437
                                          s->sample_rate + 0.5);
438
            n = s->exponent_sizes[k];
439
            j = 0;
440
            pos = 0;
441
            for(i=0;i<n;i++) {
442
                int start, end;
443
                start = pos;
444
                pos += s->exponent_bands[k][i];
445
                end = pos;
446
                if (start < s->high_band_start[k])
447
                    start = s->high_band_start[k];
448
                if (end > s->coefs_end[k])
449
                    end = s->coefs_end[k];
450
                if (end > start)
451
                    s->exponent_high_bands[k][j++] = end - start;
452
            }
453
            s->exponent_high_sizes[k] = j;
454
#if 0
455
            trace("%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
456
                  s->frame_len >> k, 
457
                  s->coefs_end[k],
458
                  s->high_band_start[k],
459
                  s->exponent_high_sizes[k]);
460
            for(j=0;j<s->exponent_high_sizes[k];j++)
461
                trace(" %d", s->exponent_high_bands[k][j]);
462
            trace("\n");
463
#endif
464
        }
465
    }
466

    
467
#ifdef DEBUG_TRACE
468
    {
469
        int i, j;
470
        for(i = 0; i < s->nb_block_sizes; i++) {
471
            trace("%5d: n=%2d:", 
472
                   s->frame_len >> i, 
473
                   s->exponent_sizes[i]);
474
            for(j=0;j<s->exponent_sizes[i];j++)
475
                trace(" %d", s->exponent_bands[i][j]);
476
            trace("\n");
477
        }
478
    }
479
#endif
480

    
481
    /* init MDCT */
482
    for(i = 0; i < s->nb_block_sizes; i++)
483
        ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1);
484
    
485
    /* init MDCT windows : simple sinus window */
486
    for(i = 0; i < s->nb_block_sizes; i++) {
487
        int n, j;
488
        float alpha;
489
        n = 1 << (s->frame_len_bits - i);
490
        window = av_malloc(sizeof(float) * n);
491
        alpha = M_PI / (2.0 * n);
492
        for(j=0;j<n;j++) {
493
            window[n - j - 1] = sin((j + 0.5) * alpha);
494
        }
495
        s->windows[i] = window;
496
    }
497

    
498
    s->reset_block_lengths = 1;
499
    
500
    if (s->use_noise_coding) {
501

    
502
        /* init the noise generator */
503
        if (s->use_exp_vlc)
504
            s->noise_mult = 0.02;
505
        else
506
            s->noise_mult = 0.04;
507
               
508
#if defined(DEBUG_TRACE)
509
        for(i=0;i<NOISE_TAB_SIZE;i++)
510
            s->noise_table[i] = 1.0 * s->noise_mult;
511
#else
512
        {
513
            unsigned int seed;
514
            float norm;
515
            seed = 1;
516
            norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
517
            for(i=0;i<NOISE_TAB_SIZE;i++) {
518
                seed = seed * 314159 + 1;
519
                s->noise_table[i] = (float)((int)seed) * norm;
520
            }
521
        }
522
#endif
523
        init_vlc(&s->hgain_vlc, 9, sizeof(hgain_huffbits), 
524
                 hgain_huffbits, 1, 1,
525
                 hgain_huffcodes, 2, 2);
526
    }
527

    
528
    if (s->use_exp_vlc) {
529
        init_vlc(&s->exp_vlc, 9, sizeof(scale_huffbits), 
530
                 scale_huffbits, 1, 1,
531
                 scale_huffcodes, 4, 4);
532
    } else {
533
        wma_lsp_to_curve_init(s, s->frame_len);
534
    }
535

    
536
    /* choose the VLC tables for the coefficients */
537
    coef_vlc_table = 2;
538
    if (s->sample_rate >= 32000) {
539
        if (bps1 < 0.72)
540
            coef_vlc_table = 0;
541
        else if (bps1 < 1.16)
542
            coef_vlc_table = 1;
543
    }
544

    
545
    init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
546
                  &coef_vlcs[coef_vlc_table * 2]);
547
    init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
548
                  &coef_vlcs[coef_vlc_table * 2 + 1]);
549
    return 0;
550
}
551

    
552
/* interpolate values for a bigger or smaller block. The block must
553
   have multiple sizes */
554
static void interpolate_array(float *scale, int old_size, int new_size)
555
{
556
    int i, j, jincr, k;
557
    float v;
558

    
559
    if (new_size > old_size) {
560
        jincr = new_size / old_size;
561
        j = new_size;
562
        for(i = old_size - 1; i >=0; i--) {
563
            v = scale[i];
564
            k = jincr;
565
            do {
566
                scale[--j] = v;
567
            } while (--k);
568
        }
569
    } else if (new_size < old_size) {
570
        j = 0;
571
        jincr = old_size / new_size;
572
        for(i = 0; i < new_size; i++) {
573
            scale[i] = scale[j];
574
            j += jincr;
575
        }
576
    }
577
}
578

    
579
/* compute x^-0.25 with an exponent and mantissa table. We use linear
580
   interpolation to reduce the mantissa table size at a small speed
581
   expense (linear interpolation approximately doubles the number of
582
   bits of precision). */
583
static inline float pow_m1_4(WMADecodeContext *s, float x)
584
{
585
    union {
586
        float f;
587
        unsigned int v;
588
    } u, t;
589
    unsigned int e, m;
590
    float a, b;
591

    
592
    u.f = x;
593
    e = u.v >> 23;
594
    m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
595
    /* build interpolation scale: 1 <= t < 2. */
596
    t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
597
    a = s->lsp_pow_m_table1[m];
598
    b = s->lsp_pow_m_table2[m];
599
    return s->lsp_pow_e_table[e] * (a + b * t.f);
600
}
601

    
602
static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len)
603
{  
604
    float wdel, a, b;
605
    int i, e, m;
606

    
607
    wdel = M_PI / frame_len;
608
    for(i=0;i<frame_len;i++)
609
        s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
610

    
611
    /* tables for x^-0.25 computation */
612
    for(i=0;i<256;i++) {
613
        e = i - 126;
614
        s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
615
    }
616

    
617
    /* NOTE: these two tables are needed to avoid two operations in
618
       pow_m1_4 */
619
    b = 1.0;
620
    for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
621
        m = (1 << LSP_POW_BITS) + i;
622
        a = (float)m * (0.5 / (1 << LSP_POW_BITS));
623
        a = pow(a, -0.25);
624
        s->lsp_pow_m_table1[i] = 2 * a - b;
625
        s->lsp_pow_m_table2[i] = b - a;
626
        b = a;
627
    }
628
#if 0
629
    for(i=1;i<20;i++) {
630
        float v, r1, r2;
631
        v = 5.0 / i;
632
        r1 = pow_m1_4(s, v);
633
        r2 = pow(v,-0.25);
634
        printf("%f^-0.25=%f e=%f\n", v, r1, r2 - r1);
635
    }
636
#endif
637
}
638

    
639
/* NOTE: We use the same code as Vorbis here */
640
/* XXX: optimize it further with SSE/3Dnow */
641
static void wma_lsp_to_curve(WMADecodeContext *s, 
642
                             float *out, float *val_max_ptr, 
643
                             int n, float *lsp)
644
{
645
    int i, j;
646
    float p, q, w, v, val_max;
647

    
648
    val_max = 0;
649
    for(i=0;i<n;i++) {
650
        p = 0.5f;
651
        q = 0.5f;
652
        w = s->lsp_cos_table[i];
653
        for(j=1;j<NB_LSP_COEFS;j+=2){
654
            q *= w - lsp[j - 1];
655
            p *= w - lsp[j];
656
        }
657
        p *= p * (2.0f - w);
658
        q *= q * (2.0f + w);
659
        v = p + q;
660
        v = pow_m1_4(s, v);
661
        if (v > val_max)
662
            val_max = v;
663
        out[i] = v;
664
    }
665
    *val_max_ptr = val_max;
666
}
667

    
668
/* decode exponents coded with LSP coefficients (same idea as Vorbis) */
669
static void decode_exp_lsp(WMADecodeContext *s, int ch)
670
{
671
    float lsp_coefs[NB_LSP_COEFS];
672
    int val, i;
673

    
674
    for(i = 0; i < NB_LSP_COEFS; i++) {
675
        if (i == 0 || i >= 8)
676
            val = get_bits(&s->gb, 3);
677
        else
678
            val = get_bits(&s->gb, 4);
679
        lsp_coefs[i] = lsp_codebook[i][val];
680
    }
681

    
682
    wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
683
                     s->block_len, lsp_coefs);
684
}
685

    
686
/* decode exponents coded with VLC codes */
687
static int decode_exp_vlc(WMADecodeContext *s, int ch)
688
{
689
    int last_exp, n, code;
690
    const uint16_t *ptr, *band_ptr;
691
    float v, *q, max_scale, *q_end;
692
    
693
    band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
694
    ptr = band_ptr;
695
    q = s->exponents[ch];
696
    q_end = q + s->block_len;
697
    max_scale = 0;
698
    if (s->version == 1) {
699
        last_exp = get_bits(&s->gb, 5) + 10;
700
        /* XXX: use a table */
701
        v = pow(10, last_exp * (1.0 / 16.0));
702
        max_scale = v;
703
        n = *ptr++;
704
        do {
705
            *q++ = v;
706
        } while (--n);
707
    }
708
    last_exp = 36;
709
    while (q < q_end) {
710
        code = get_vlc(&s->gb, &s->exp_vlc);
711
        if (code < 0)
712
            return -1;
713
        /* NOTE: this offset is the same as MPEG4 AAC ! */
714
        last_exp += code - 60;
715
        /* XXX: use a table */
716
        v = pow(10, last_exp * (1.0 / 16.0));
717
        if (v > max_scale)
718
            max_scale = v;
719
        n = *ptr++;
720
        do {
721
            *q++ = v;
722
        } while (--n);
723
    }
724
    s->max_exponent[ch] = max_scale;
725
    return 0;
726
}
727

    
728
/* return 0 if OK. return 1 if last block of frame. return -1 if
729
   unrecorrable error. */
730
static int wma_decode_block(WMADecodeContext *s)
731
{
732
    int n, v, a, ch, code, bsize;
733
    int coef_nb_bits, total_gain, parse_exponents;
734
    float window[BLOCK_MAX_SIZE * 2];
735
    int nb_coefs[MAX_CHANNELS];
736
    float mdct_norm;
737

    
738
    trace("***decode_block: %d:%d\n", frame_count - 1, s->block_num);
739

    
740
    /* compute current block length */
741
    if (s->use_variable_block_len) {
742
        n = av_log2(s->nb_block_sizes - 1) + 1;
743
    
744
        if (s->reset_block_lengths) {
745
            s->reset_block_lengths = 0;
746
            v = get_bits(&s->gb, n);
747
            if (v >= s->nb_block_sizes)
748
                return -1;
749
            s->prev_block_len_bits = s->frame_len_bits - v;
750
            v = get_bits(&s->gb, n);
751
            if (v >= s->nb_block_sizes)
752
                return -1;
753
            s->block_len_bits = s->frame_len_bits - v;
754
        } else {
755
            /* update block lengths */
756
            s->prev_block_len_bits = s->block_len_bits;
757
            s->block_len_bits = s->next_block_len_bits;
758
        }
759
        v = get_bits(&s->gb, n);
760
        if (v >= s->nb_block_sizes)
761
            return -1;
762
        s->next_block_len_bits = s->frame_len_bits - v;
763
    } else {
764
        /* fixed block len */
765
        s->next_block_len_bits = s->frame_len_bits;
766
        s->prev_block_len_bits = s->frame_len_bits;
767
        s->block_len_bits = s->frame_len_bits;
768
    }
769

    
770
    /* now check if the block length is coherent with the frame length */
771
    s->block_len = 1 << s->block_len_bits;
772
    if ((s->block_pos + s->block_len) > s->frame_len)
773
        return -1;
774

    
775
    if (s->nb_channels == 2) {
776
        s->ms_stereo = get_bits(&s->gb, 1);
777
    }
778
    v = 0;
779
    for(ch = 0; ch < s->nb_channels; ch++) {
780
        a = get_bits(&s->gb, 1);
781
        s->channel_coded[ch] = a;
782
        v |= a;
783
    }
784
    /* if no channel coded, no need to go further */
785
    /* XXX: fix potential framing problems */
786
    if (!v)
787
        goto next;
788

    
789
    bsize = s->frame_len_bits - s->block_len_bits;
790

    
791
    /* read total gain and extract corresponding number of bits for
792
       coef escape coding */
793
    total_gain = 1;
794
    for(;;) {
795
        a = get_bits(&s->gb, 7);
796
        total_gain += a;
797
        if (a != 127)
798
            break;
799
    }
800
    
801
    if (total_gain < 15)
802
        coef_nb_bits = 13;
803
    else if (total_gain < 32)
804
        coef_nb_bits = 12;
805
    else if (total_gain < 40)
806
        coef_nb_bits = 11;
807
    else if (total_gain < 45)
808
        coef_nb_bits = 10;
809
    else
810
        coef_nb_bits = 9;
811

    
812
    /* compute number of coefficients */
813
    n = s->coefs_end[bsize] - s->coefs_start;
814
    for(ch = 0; ch < s->nb_channels; ch++)
815
        nb_coefs[ch] = n;
816

    
817
    /* complex coding */
818
    if (s->use_noise_coding) {
819

    
820
        for(ch = 0; ch < s->nb_channels; ch++) {
821
            if (s->channel_coded[ch]) {
822
                int i, n, a;
823
                n = s->exponent_high_sizes[bsize];
824
                for(i=0;i<n;i++) {
825
                    a = get_bits(&s->gb, 1);
826
                    s->high_band_coded[ch][i] = a;
827
                    /* if noise coding, the coefficients are not transmitted */
828
                    if (a)
829
                        nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
830
                }
831
            }
832
        }
833
        for(ch = 0; ch < s->nb_channels; ch++) {
834
            if (s->channel_coded[ch]) {
835
                int i, n, val, code;
836

    
837
                n = s->exponent_high_sizes[bsize];
838
                val = (int)0x80000000;
839
                for(i=0;i<n;i++) {
840
                    if (s->high_band_coded[ch][i]) {
841
                        if (val == (int)0x80000000) {
842
                            val = get_bits(&s->gb, 7) - 19;
843
                        } else {
844
                            code = get_vlc(&s->gb, &s->hgain_vlc);
845
                            if (code < 0)
846
                                return -1;
847
                            val += code - 18;
848
                        }
849
                        s->high_band_values[ch][i] = val;
850
                    }
851
                }
852
            }
853
        }
854
    }
855
           
856
    /* exposant can be interpolated in short blocks. */
857
    parse_exponents = 1;
858
    if (s->block_len_bits != s->frame_len_bits) {
859
        parse_exponents = get_bits(&s->gb, 1);
860
    }
861
    
862
    if (parse_exponents) {
863
        for(ch = 0; ch < s->nb_channels; ch++) {
864
            if (s->channel_coded[ch]) {
865
                if (s->use_exp_vlc) {
866
                    if (decode_exp_vlc(s, ch) < 0)
867
                        return -1;
868
                } else {
869
                    decode_exp_lsp(s, ch);
870
                }
871
            }
872
        }
873
    } else {
874
        for(ch = 0; ch < s->nb_channels; ch++) {
875
            if (s->channel_coded[ch]) {
876
                interpolate_array(s->exponents[ch], 1 << s->prev_block_len_bits, 
877
                                  s->block_len);
878
            }
879
        }
880
    }
881

    
882
    /* parse spectral coefficients : just RLE encoding */
883
    for(ch = 0; ch < s->nb_channels; ch++) {
884
        if (s->channel_coded[ch]) {
885
            VLC *coef_vlc;
886
            int level, run, sign, tindex;
887
            int16_t *ptr, *eptr;
888
            const int16_t *level_table, *run_table;
889

    
890
            /* special VLC tables are used for ms stereo because
891
               there is potentially less energy there */
892
            tindex = (ch == 1 && s->ms_stereo);
893
            coef_vlc = &s->coef_vlc[tindex];
894
            run_table = s->run_table[tindex];
895
            level_table = s->level_table[tindex];
896
            /* XXX: optimize */
897
            ptr = &s->coefs1[ch][0];
898
            eptr = ptr + nb_coefs[ch];
899
            memset(ptr, 0, s->block_len * sizeof(int16_t));
900
            for(;;) {
901
                code = get_vlc(&s->gb, coef_vlc);
902
                if (code < 0)
903
                    return -1;
904
                if (code == 1) {
905
                    /* EOB */
906
                    break;
907
                } else if (code == 0) {
908
                    /* escape */
909
                    level = get_bits(&s->gb, coef_nb_bits);
910
                    /* NOTE: this is rather suboptimal. reading
911
                       block_len_bits would be better */
912
                    run = get_bits(&s->gb, s->frame_len_bits);
913
                } else {
914
                    /* normal code */
915
                    run = run_table[code];
916
                    level = level_table[code];
917
                }
918
                sign = get_bits(&s->gb, 1);
919
                if (!sign)
920
                    level = -level;
921
                ptr += run;
922
                if (ptr >= eptr)
923
                    return -1;
924
                *ptr++ = level;
925
                /* NOTE: EOB can be omitted */
926
                if (ptr >= eptr)
927
                    break;
928
            }
929
        }
930
        if (s->version == 1 && s->nb_channels >= 2) {
931
            align_get_bits(&s->gb);
932
        }
933
    }
934
     
935
    /* normalize */
936
    {
937
        int n4 = s->block_len / 2;
938
        mdct_norm = 1.0 / (float)n4;
939
        if (s->version == 1) {
940
            mdct_norm *= sqrt(n4);
941
        }
942
    }
943

    
944
    /* finally compute the MDCT coefficients */
945
    for(ch = 0; ch < s->nb_channels; ch++) {
946
        if (s->channel_coded[ch]) {
947
            int16_t *coefs1;
948
            float *coefs, *exponents, mult, mult1, noise, *exp_ptr;
949
            int i, j, n, n1, last_high_band;
950
            float exp_power[HIGH_BAND_MAX_SIZE];
951

    
952
            coefs1 = s->coefs1[ch];
953
            exponents = s->exponents[ch];
954
            mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
955
            mult *= mdct_norm;
956
            coefs = s->coefs[ch];
957
            if (s->use_noise_coding) {
958
                mult1 = mult;
959
                /* very low freqs : noise */
960
                for(i = 0;i < s->coefs_start; i++) {
961
                    *coefs++ = s->noise_table[s->noise_index] * (*exponents++) * mult1;
962
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
963
                }
964
                
965
                n1 = s->exponent_high_sizes[bsize];
966

    
967
                /* compute power of high bands */
968
                exp_ptr = exponents + 
969
                    s->high_band_start[bsize] - 
970
                    s->coefs_start;
971
                last_high_band = 0; /* avoid warning */
972
                for(j=0;j<n1;j++) {
973
                    n = s->exponent_high_bands[s->frame_len_bits - 
974
                                              s->block_len_bits][j];
975
                    if (s->high_band_coded[ch][j]) {
976
                        float e2, v;
977
                        e2 = 0;
978
                        for(i = 0;i < n; i++) {
979
                            v = exp_ptr[i];
980
                            e2 += v * v;
981
                        }
982
                        exp_power[j] = e2 / n;
983
                        last_high_band = j;
984
                        trace("%d: power=%f (%d)\n", j, exp_power[j], n);
985
                    }
986
                    exp_ptr += n;
987
                }
988

    
989
                /* main freqs and high freqs */
990
                for(j=-1;j<n1;j++) {
991
                    if (j < 0) {
992
                        n = s->high_band_start[bsize] - 
993
                            s->coefs_start;
994
                    } else {
995
                        n = s->exponent_high_bands[s->frame_len_bits - 
996
                                                  s->block_len_bits][j];
997
                    }
998
                    if (j >= 0 && s->high_band_coded[ch][j]) {
999
                        /* use noise with specified power */
1000
                        mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
1001
                        /* XXX: use a table */
1002
                        mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
1003
                        mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
1004
                        mult1 *= mdct_norm;
1005
                        for(i = 0;i < n; i++) {
1006
                            noise = s->noise_table[s->noise_index];
1007
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
1008
                            *coefs++ = (*exponents++) * noise * mult1;
1009
                        }
1010
                    } else {
1011
                        /* coded values + small noise */
1012
                        for(i = 0;i < n; i++) {
1013
                            noise = s->noise_table[s->noise_index];
1014
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
1015
                            *coefs++ = ((*coefs1++) + noise) * (*exponents++) * mult;
1016
                        }
1017
                    }
1018
                }
1019

    
1020
                /* very high freqs : noise */
1021
                n = s->block_len - s->coefs_end[bsize];
1022
                mult1 = mult * exponents[-1];
1023
                for(i = 0; i < n; i++) {
1024
                    *coefs++ = s->noise_table[s->noise_index] * mult1;
1025
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
1026
                }
1027
            } else {
1028
                /* XXX: optimize more */
1029
                for(i = 0;i < s->coefs_start; i++)
1030
                    *coefs++ = 0.0;
1031
                n = nb_coefs[ch];
1032
                for(i = 0;i < n; i++) {
1033
                    *coefs++ = coefs1[i] * exponents[i] * mult;
1034
                }
1035
                n = s->block_len - s->coefs_end[bsize];
1036
                for(i = 0;i < n; i++)
1037
                    *coefs++ = 0.0;
1038
            }
1039
        }
1040
    }
1041

    
1042
#ifdef DEBUG_TRACE
1043
    for(ch = 0; ch < s->nb_channels; ch++) {
1044
        if (s->channel_coded[ch]) {
1045
            dump_floats("exponents", 3, s->exponents[ch], s->block_len);
1046
            dump_floats("coefs", 1, s->coefs[ch], s->block_len);
1047
        }
1048
    }
1049
#endif
1050
    
1051
    if (s->ms_stereo && s->channel_coded[1]) {
1052
        float a, b;
1053
        int i;
1054

    
1055
        /* nominal case for ms stereo: we do it before mdct */
1056
        /* no need to optimize this case because it should almost
1057
           never happen */
1058
        if (!s->channel_coded[0]) {
1059
#ifdef DEBUG_TRACE
1060
            trace("rare ms-stereo case happened\n");
1061
#endif
1062
            memset(s->coefs[0], 0, sizeof(float) * s->block_len);
1063
            s->channel_coded[0] = 1;
1064
        }
1065
        
1066
        for(i = 0; i < s->block_len; i++) {
1067
            a = s->coefs[0][i];
1068
            b = s->coefs[1][i];
1069
            s->coefs[0][i] = a + b;
1070
            s->coefs[1][i] = a - b;
1071
        }
1072
    }
1073

    
1074
    /* build the window : we ensure that when the windows overlap
1075
       their squared sum is always 1 (MDCT reconstruction rule) */
1076
    /* XXX: merge with output */
1077
    {
1078
        int i, next_block_len, block_len, prev_block_len, n;
1079
        float *wptr;
1080

    
1081
        block_len = s->block_len;
1082
        prev_block_len = 1 << s->prev_block_len_bits;
1083
        next_block_len = 1 << s->next_block_len_bits;
1084

    
1085
        /* right part */
1086
        wptr = window + block_len;
1087
        if (block_len <= next_block_len) {
1088
            for(i=0;i<block_len;i++)
1089
                *wptr++ = s->windows[bsize][i];
1090
        } else {
1091
            /* overlap */
1092
            n = (block_len / 2) - (next_block_len / 2);
1093
            for(i=0;i<n;i++)
1094
                *wptr++ = 1.0;
1095
            for(i=0;i<next_block_len;i++)
1096
                *wptr++ = s->windows[s->frame_len_bits - s->next_block_len_bits][i];
1097
            for(i=0;i<n;i++)
1098
                *wptr++ = 0.0;
1099
        }
1100

    
1101
        /* left part */
1102
        wptr = window + block_len;
1103
        if (block_len <= prev_block_len) {
1104
            for(i=0;i<block_len;i++)
1105
                *--wptr = s->windows[bsize][i];
1106
        } else {
1107
            /* overlap */
1108
            n = (block_len / 2) - (prev_block_len / 2);
1109
            for(i=0;i<n;i++)
1110
                *--wptr = 1.0;
1111
            for(i=0;i<prev_block_len;i++)
1112
                *--wptr = s->windows[s->frame_len_bits - s->prev_block_len_bits][i];
1113
            for(i=0;i<n;i++)
1114
                *--wptr = 0.0;
1115
        }
1116
    }
1117

    
1118
    
1119
    for(ch = 0; ch < s->nb_channels; ch++) {
1120
        if (s->channel_coded[ch]) {
1121
            FFTSample output[BLOCK_MAX_SIZE * 2];
1122
            float *ptr;
1123
            int i, n4, index, n;
1124

    
1125
            n = s->block_len;
1126
            n4 = s->block_len / 2;
1127
            ff_imdct_calc(&s->mdct_ctx[bsize], 
1128
                          output, s->coefs[ch], s->mdct_tmp);
1129

    
1130
            /* XXX: optimize all that by build the window and
1131
               multipying/adding at the same time */
1132
            /* multiply by the window */
1133
            for(i=0;i<n * 2;i++) {
1134
                output[i] *= window[i];
1135
            }
1136

    
1137
            /* add in the frame */
1138
            index = (s->frame_len / 2) + s->block_pos - n4;
1139
            ptr = &s->frame_out[ch][index];
1140
            for(i=0;i<n * 2;i++) {
1141
                *ptr += output[i];
1142
                ptr++;
1143
            }
1144

    
1145
            /* specific fast case for ms-stereo : add to second
1146
               channel if it is not coded */
1147
            if (s->ms_stereo && !s->channel_coded[1]) {
1148
                ptr = &s->frame_out[1][index];
1149
                for(i=0;i<n * 2;i++) {
1150
                    *ptr += output[i];
1151
                    ptr++;
1152
                }
1153
            }
1154
        }
1155
    }
1156
 next:
1157
    /* update block number */
1158
    s->block_num++;
1159
    s->block_pos += s->block_len;
1160
    if (s->block_pos >= s->frame_len)
1161
        return 1;
1162
    else
1163
        return 0;
1164
}
1165

    
1166
/* decode a frame of frame_len samples */
1167
static int wma_decode_frame(WMADecodeContext *s, int16_t *samples)
1168
{
1169
    int ret, i, n, a, ch, incr;
1170
    int16_t *ptr;
1171
    float *iptr;
1172

    
1173
    trace("***decode_frame: %d size=%d\n", frame_count++, s->frame_len);
1174

    
1175
    /* read each block */
1176
    s->block_num = 0;
1177
    s->block_pos = 0;
1178
    for(;;) {
1179
        ret = wma_decode_block(s);
1180
        if (ret < 0) 
1181
            return -1;
1182
        if (ret)
1183
            break;
1184
    }
1185

    
1186
    /* convert frame to integer */
1187
    n = s->frame_len;
1188
    incr = s->nb_channels;
1189
    for(ch = 0; ch < s->nb_channels; ch++) {
1190
        ptr = samples + ch;
1191
        iptr = s->frame_out[ch];
1192

    
1193
        for(i=0;i<n;i++) {
1194
            a = lrintf(*iptr++);
1195
            if (a > 32767)
1196
                a = 32767;
1197
            else if (a < -32768)
1198
                a = -32768;
1199
            *ptr = a;
1200
            ptr += incr;
1201
        }
1202
        /* prepare for next block */
1203
        memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
1204
                s->frame_len * sizeof(float));
1205
        /* XXX: suppress this */
1206
        memset(&s->frame_out[ch][s->frame_len], 0, 
1207
               s->frame_len * sizeof(float));
1208
    }
1209

    
1210
#ifdef DEBUG_TRACE
1211
    dump_shorts("samples", samples, n * s->nb_channels);
1212
#endif
1213
    return 0;
1214
}
1215

    
1216
static int wma_decode_superframe(AVCodecContext *avctx, 
1217
                                 void *data, int *data_size,
1218
                                 UINT8 *buf, int buf_size)
1219
{
1220
    WMADecodeContext *s = avctx->priv_data;
1221
    int nb_frames, bit_offset, i, pos, len;
1222
    uint8_t *q;
1223
    int16_t *samples;
1224
    
1225
    trace("***decode_superframe:\n");
1226

    
1227
    samples = data;
1228

    
1229
    init_get_bits(&s->gb, buf, buf_size);
1230
    
1231
    if (s->use_bit_reservoir) {
1232
        /* read super frame header */
1233
        get_bits(&s->gb, 4); /* super frame index */
1234
        nb_frames = get_bits(&s->gb, 4) - 1;
1235

    
1236
        bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
1237

    
1238
        if (s->last_superframe_len > 0) {
1239
            //        printf("skip=%d\n", s->last_bitoffset);
1240
            /* add bit_offset bits to last frame */
1241
            if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) > 
1242
                MAX_CODED_SUPERFRAME_SIZE)
1243
                goto fail;
1244
            q = s->last_superframe + s->last_superframe_len;
1245
            len = bit_offset;
1246
            while (len > 0) {
1247
                *q++ = (get_bits)(&s->gb, 8);
1248
                len -= 8;
1249
            }
1250
            if (len > 0) {
1251
                *q++ = (get_bits)(&s->gb, len) << (8 - len);
1252
            }
1253
            
1254
            /* XXX: bit_offset bits into last frame */
1255
            init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE);
1256
            /* skip unused bits */
1257
            if (s->last_bitoffset > 0)
1258
                skip_bits(&s->gb, s->last_bitoffset);
1259
            /* this frame is stored in the last superframe and in the
1260
               current one */
1261
            if (wma_decode_frame(s, samples) < 0)
1262
                goto fail;
1263
            samples += s->nb_channels * s->frame_len;
1264
        }
1265

    
1266
        /* read each frame starting from bit_offset */
1267
        pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
1268
        init_get_bits(&s->gb, buf + (pos >> 3), MAX_CODED_SUPERFRAME_SIZE - (pos >> 3));
1269
        len = pos & 7;
1270
        if (len > 0)
1271
            skip_bits(&s->gb, len);
1272
    
1273
        s->reset_block_lengths = 1;
1274
        for(i=0;i<nb_frames;i++) {
1275
            if (wma_decode_frame(s, samples) < 0)
1276
                goto fail;
1277
            samples += s->nb_channels * s->frame_len;
1278
        }
1279

    
1280
        /* we copy the end of the frame in the last frame buffer */
1281
        pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
1282
        s->last_bitoffset = pos & 7;
1283
        pos >>= 3;
1284
        len = buf_size - pos;
1285
        if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
1286
            goto fail;
1287
        }
1288
        s->last_superframe_len = len;
1289
        memcpy(s->last_superframe, buf + pos, len);
1290
    } else {
1291
        /* single frame decode */
1292
        if (wma_decode_frame(s, samples) < 0)
1293
            goto fail;
1294
        samples += s->nb_channels * s->frame_len;
1295
    }
1296
    *data_size = (int8_t *)samples - (int8_t *)data;
1297
    return s->block_align;
1298
 fail:
1299
    /* when error, we reset the bit reservoir */
1300
    s->last_superframe_len = 0;
1301
    return -1;
1302
}
1303

    
1304
static int wma_decode_end(AVCodecContext *avctx)
1305
{
1306
    WMADecodeContext *s = avctx->priv_data;
1307
    int i;
1308

    
1309
    for(i = 0; i < s->nb_block_sizes; i++)
1310
        ff_mdct_end(&s->mdct_ctx[i]);
1311
    for(i = 0; i < s->nb_block_sizes; i++)
1312
        av_free(s->windows[i]);
1313

    
1314
    if (s->use_exp_vlc) {
1315
        free_vlc(&s->exp_vlc);
1316
    }
1317
    if (s->use_noise_coding) {
1318
        free_vlc(&s->hgain_vlc);
1319
    }
1320
    for(i = 0;i < 2; i++) {
1321
        free_vlc(&s->coef_vlc[i]);
1322
        av_free(s->run_table[i]);
1323
        av_free(s->level_table[i]);
1324
    }
1325
    
1326
    return 0;
1327
}
1328

    
1329
AVCodec wmav1_decoder =
1330
{
1331
    "wmav1",
1332
    CODEC_TYPE_AUDIO,
1333
    CODEC_ID_WMAV1,
1334
    sizeof(WMADecodeContext),
1335
    wma_decode_init,
1336
    NULL,
1337
    wma_decode_end,
1338
    wma_decode_superframe,
1339
};
1340

    
1341
AVCodec wmav2_decoder =
1342
{
1343
    "wmav2",
1344
    CODEC_TYPE_AUDIO,
1345
    CODEC_ID_WMAV2,
1346
    sizeof(WMADecodeContext),
1347
    wma_decode_init,
1348
    NULL,
1349
    wma_decode_end,
1350
    wma_decode_superframe,
1351
};