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1
/*
2
 * WMA compatible decoder
3
 * Copyright (c) 2002 The FFmpeg Project
4
 *
5
 * This file is part of FFmpeg.
6
 *
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 * FFmpeg is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
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 * FFmpeg is distributed in the hope that it will be useful,
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
16
 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
21

    
22
/**
23
 * @file libavcodec/wmadec.c
24
 * WMA compatible decoder.
25
 * This decoder handles Microsoft Windows Media Audio data, versions 1 & 2.
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 * WMA v1 is identified by audio format 0x160 in Microsoft media files
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 * (ASF/AVI/WAV). WMA v2 is identified by audio format 0x161.
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 *
29
 * To use this decoder, a calling application must supply the extra data
30
 * bytes provided with the WMA data. These are the extra, codec-specific
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 * bytes at the end of a WAVEFORMATEX data structure. Transmit these bytes
32
 * to the decoder using the extradata[_size] fields in AVCodecContext. There
33
 * should be 4 extra bytes for v1 data and 6 extra bytes for v2 data.
34
 */
35

    
36
#include "avcodec.h"
37
#include "wma.h"
38

    
39
#undef NDEBUG
40
#include <assert.h>
41

    
42
#define EXPVLCBITS 8
43
#define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)
44

    
45
#define HGAINVLCBITS 9
46
#define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
47

    
48
static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len);
49

    
50
#ifdef TRACE
51
static void dump_shorts(WMACodecContext *s, const char *name, const short *tab, int n)
52
{
53
    int i;
54

    
55
    tprintf(s->avctx, "%s[%d]:\n", name, n);
56
    for(i=0;i<n;i++) {
57
        if ((i & 7) == 0)
58
            tprintf(s->avctx, "%4d: ", i);
59
        tprintf(s->avctx, " %5d.0", tab[i]);
60
        if ((i & 7) == 7)
61
            tprintf(s->avctx, "\n");
62
    }
63
}
64

    
65
static void dump_floats(WMACodecContext *s, const char *name, int prec, const float *tab, int n)
66
{
67
    int i;
68

    
69
    tprintf(s->avctx, "%s[%d]:\n", name, n);
70
    for(i=0;i<n;i++) {
71
        if ((i & 7) == 0)
72
            tprintf(s->avctx, "%4d: ", i);
73
        tprintf(s->avctx, " %8.*f", prec, tab[i]);
74
        if ((i & 7) == 7)
75
            tprintf(s->avctx, "\n");
76
    }
77
    if ((i & 7) != 0)
78
        tprintf(s->avctx, "\n");
79
}
80
#endif
81

    
82
static int wma_decode_init(AVCodecContext * avctx)
83
{
84
    WMACodecContext *s = avctx->priv_data;
85
    int i, flags2;
86
    uint8_t *extradata;
87

    
88
    s->avctx = avctx;
89

    
90
    /* extract flag infos */
91
    flags2 = 0;
92
    extradata = avctx->extradata;
93
    if (avctx->codec->id == CODEC_ID_WMAV1 && avctx->extradata_size >= 4) {
94
        flags2 = AV_RL16(extradata+2);
95
    } else if (avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 6) {
96
        flags2 = AV_RL16(extradata+4);
97
    }
98
// for(i=0; i<avctx->extradata_size; i++)
99
//     av_log(NULL, AV_LOG_ERROR, "%02X ", extradata[i]);
100

    
101
    s->use_exp_vlc = flags2 & 0x0001;
102
    s->use_bit_reservoir = flags2 & 0x0002;
103
    s->use_variable_block_len = flags2 & 0x0004;
104

    
105
    if(ff_wma_init(avctx, flags2)<0)
106
        return -1;
107

    
108
    /* init MDCT */
109
    for(i = 0; i < s->nb_block_sizes; i++)
110
        ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1, 1.0);
111

    
112
    if (s->use_noise_coding) {
113
        init_vlc(&s->hgain_vlc, HGAINVLCBITS, sizeof(ff_wma_hgain_huffbits),
114
                 ff_wma_hgain_huffbits, 1, 1,
115
                 ff_wma_hgain_huffcodes, 2, 2, 0);
116
    }
117

    
118
    if (s->use_exp_vlc) {
119
        init_vlc(&s->exp_vlc, EXPVLCBITS, sizeof(ff_wma_scale_huffbits), //FIXME move out of context
120
                 ff_wma_scale_huffbits, 1, 1,
121
                 ff_wma_scale_huffcodes, 4, 4, 0);
122
    } else {
123
        wma_lsp_to_curve_init(s, s->frame_len);
124
    }
125

    
126
    avctx->sample_fmt = SAMPLE_FMT_S16;
127
    return 0;
128
}
129

    
130
/**
131
 * compute x^-0.25 with an exponent and mantissa table. We use linear
132
 * interpolation to reduce the mantissa table size at a small speed
133
 * expense (linear interpolation approximately doubles the number of
134
 * bits of precision).
135
 */
136
static inline float pow_m1_4(WMACodecContext *s, float x)
137
{
138
    union {
139
        float f;
140
        unsigned int v;
141
    } u, t;
142
    unsigned int e, m;
143
    float a, b;
144

    
145
    u.f = x;
146
    e = u.v >> 23;
147
    m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
148
    /* build interpolation scale: 1 <= t < 2. */
149
    t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
150
    a = s->lsp_pow_m_table1[m];
151
    b = s->lsp_pow_m_table2[m];
152
    return s->lsp_pow_e_table[e] * (a + b * t.f);
153
}
154

    
155
static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len)
156
{
157
    float wdel, a, b;
158
    int i, e, m;
159

    
160
    wdel = M_PI / frame_len;
161
    for(i=0;i<frame_len;i++)
162
        s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
163

    
164
    /* tables for x^-0.25 computation */
165
    for(i=0;i<256;i++) {
166
        e = i - 126;
167
        s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
168
    }
169

    
170
    /* NOTE: these two tables are needed to avoid two operations in
171
       pow_m1_4 */
172
    b = 1.0;
173
    for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
174
        m = (1 << LSP_POW_BITS) + i;
175
        a = (float)m * (0.5 / (1 << LSP_POW_BITS));
176
        a = pow(a, -0.25);
177
        s->lsp_pow_m_table1[i] = 2 * a - b;
178
        s->lsp_pow_m_table2[i] = b - a;
179
        b = a;
180
    }
181
#if 0
182
    for(i=1;i<20;i++) {
183
        float v, r1, r2;
184
        v = 5.0 / i;
185
        r1 = pow_m1_4(s, v);
186
        r2 = pow(v,-0.25);
187
        printf("%f^-0.25=%f e=%f\n", v, r1, r2 - r1);
188
    }
189
#endif
190
}
191

    
192
/**
193
 * NOTE: We use the same code as Vorbis here
194
 * @todo optimize it further with SSE/3Dnow
195
 */
196
static void wma_lsp_to_curve(WMACodecContext *s,
197
                             float *out, float *val_max_ptr,
198
                             int n, float *lsp)
199
{
200
    int i, j;
201
    float p, q, w, v, val_max;
202

    
203
    val_max = 0;
204
    for(i=0;i<n;i++) {
205
        p = 0.5f;
206
        q = 0.5f;
207
        w = s->lsp_cos_table[i];
208
        for(j=1;j<NB_LSP_COEFS;j+=2){
209
            q *= w - lsp[j - 1];
210
            p *= w - lsp[j];
211
        }
212
        p *= p * (2.0f - w);
213
        q *= q * (2.0f + w);
214
        v = p + q;
215
        v = pow_m1_4(s, v);
216
        if (v > val_max)
217
            val_max = v;
218
        out[i] = v;
219
    }
220
    *val_max_ptr = val_max;
221
}
222

    
223
/**
224
 * decode exponents coded with LSP coefficients (same idea as Vorbis)
225
 */
226
static void decode_exp_lsp(WMACodecContext *s, int ch)
227
{
228
    float lsp_coefs[NB_LSP_COEFS];
229
    int val, i;
230

    
231
    for(i = 0; i < NB_LSP_COEFS; i++) {
232
        if (i == 0 || i >= 8)
233
            val = get_bits(&s->gb, 3);
234
        else
235
            val = get_bits(&s->gb, 4);
236
        lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
237
    }
238

    
239
    wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
240
                     s->block_len, lsp_coefs);
241
}
242

    
243
/** pow(10, i / 16.0) for i in -60..67 */
244
static const float pow_tab[128] = {
245
    1.7782794100389e-04, 2.0535250264571e-04,
246
    2.3713737056617e-04, 2.7384196342644e-04,
247
    3.1622776601684e-04, 3.6517412725484e-04,
248
    4.2169650342858e-04, 4.8696752516586e-04,
249
    5.6234132519035e-04, 6.4938163157621e-04,
250
    7.4989420933246e-04, 8.6596432336006e-04,
251
    1.0000000000000e-03, 1.1547819846895e-03,
252
    1.3335214321633e-03, 1.5399265260595e-03,
253
    1.7782794100389e-03, 2.0535250264571e-03,
254
    2.3713737056617e-03, 2.7384196342644e-03,
255
    3.1622776601684e-03, 3.6517412725484e-03,
256
    4.2169650342858e-03, 4.8696752516586e-03,
257
    5.6234132519035e-03, 6.4938163157621e-03,
258
    7.4989420933246e-03, 8.6596432336006e-03,
259
    1.0000000000000e-02, 1.1547819846895e-02,
260
    1.3335214321633e-02, 1.5399265260595e-02,
261
    1.7782794100389e-02, 2.0535250264571e-02,
262
    2.3713737056617e-02, 2.7384196342644e-02,
263
    3.1622776601684e-02, 3.6517412725484e-02,
264
    4.2169650342858e-02, 4.8696752516586e-02,
265
    5.6234132519035e-02, 6.4938163157621e-02,
266
    7.4989420933246e-02, 8.6596432336007e-02,
267
    1.0000000000000e-01, 1.1547819846895e-01,
268
    1.3335214321633e-01, 1.5399265260595e-01,
269
    1.7782794100389e-01, 2.0535250264571e-01,
270
    2.3713737056617e-01, 2.7384196342644e-01,
271
    3.1622776601684e-01, 3.6517412725484e-01,
272
    4.2169650342858e-01, 4.8696752516586e-01,
273
    5.6234132519035e-01, 6.4938163157621e-01,
274
    7.4989420933246e-01, 8.6596432336007e-01,
275
    1.0000000000000e+00, 1.1547819846895e+00,
276
    1.3335214321633e+00, 1.5399265260595e+00,
277
    1.7782794100389e+00, 2.0535250264571e+00,
278
    2.3713737056617e+00, 2.7384196342644e+00,
279
    3.1622776601684e+00, 3.6517412725484e+00,
280
    4.2169650342858e+00, 4.8696752516586e+00,
281
    5.6234132519035e+00, 6.4938163157621e+00,
282
    7.4989420933246e+00, 8.6596432336007e+00,
283
    1.0000000000000e+01, 1.1547819846895e+01,
284
    1.3335214321633e+01, 1.5399265260595e+01,
285
    1.7782794100389e+01, 2.0535250264571e+01,
286
    2.3713737056617e+01, 2.7384196342644e+01,
287
    3.1622776601684e+01, 3.6517412725484e+01,
288
    4.2169650342858e+01, 4.8696752516586e+01,
289
    5.6234132519035e+01, 6.4938163157621e+01,
290
    7.4989420933246e+01, 8.6596432336007e+01,
291
    1.0000000000000e+02, 1.1547819846895e+02,
292
    1.3335214321633e+02, 1.5399265260595e+02,
293
    1.7782794100389e+02, 2.0535250264571e+02,
294
    2.3713737056617e+02, 2.7384196342644e+02,
295
    3.1622776601684e+02, 3.6517412725484e+02,
296
    4.2169650342858e+02, 4.8696752516586e+02,
297
    5.6234132519035e+02, 6.4938163157621e+02,
298
    7.4989420933246e+02, 8.6596432336007e+02,
299
    1.0000000000000e+03, 1.1547819846895e+03,
300
    1.3335214321633e+03, 1.5399265260595e+03,
301
    1.7782794100389e+03, 2.0535250264571e+03,
302
    2.3713737056617e+03, 2.7384196342644e+03,
303
    3.1622776601684e+03, 3.6517412725484e+03,
304
    4.2169650342858e+03, 4.8696752516586e+03,
305
    5.6234132519035e+03, 6.4938163157621e+03,
306
    7.4989420933246e+03, 8.6596432336007e+03,
307
    1.0000000000000e+04, 1.1547819846895e+04,
308
    1.3335214321633e+04, 1.5399265260595e+04,
309
};
310

    
311
/**
312
 * decode exponents coded with VLC codes
313
 */
314
static int decode_exp_vlc(WMACodecContext *s, int ch)
315
{
316
    int last_exp, n, code;
317
    const uint16_t *ptr;
318
    float v, max_scale;
319
    uint32_t *q, *q_end, iv;
320
    const float *ptab = pow_tab + 60;
321
    const uint32_t *iptab = (const uint32_t*)ptab;
322

    
323
    ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
324
    q = (uint32_t *)s->exponents[ch];
325
    q_end = q + s->block_len;
326
    max_scale = 0;
327
    if (s->version == 1) {
328
        last_exp = get_bits(&s->gb, 5) + 10;
329
        v = ptab[last_exp];
330
        iv = iptab[last_exp];
331
        max_scale = v;
332
        n = *ptr++;
333
        do {
334
            *q++ = iv;
335
            *q++ = iv;
336
            *q++ = iv;
337
            *q++ = iv;
338
        } while (n -= 4);
339
    }else
340
        last_exp = 36;
341

    
342
    while (q < q_end) {
343
        code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
344
        if (code < 0)
345
            return -1;
346
        /* NOTE: this offset is the same as MPEG4 AAC ! */
347
        last_exp += code - 60;
348
        if ((unsigned)last_exp + 60 > FF_ARRAY_ELEMS(pow_tab))
349
            return -1;
350
        v = ptab[last_exp];
351
        iv = iptab[last_exp];
352
        if (v > max_scale)
353
            max_scale = v;
354
        n = *ptr++;
355
        do {
356
            *q++ = iv;
357
            *q++ = iv;
358
            *q++ = iv;
359
            *q++ = iv;
360
        } while (n -= 4);
361
    }
362
    s->max_exponent[ch] = max_scale;
363
    return 0;
364
}
365

    
366

    
367
/**
368
 * Apply MDCT window and add into output.
369
 *
370
 * We ensure that when the windows overlap their squared sum
371
 * is always 1 (MDCT reconstruction rule).
372
 */
373
static void wma_window(WMACodecContext *s, float *out)
374
{
375
    float *in = s->output;
376
    int block_len, bsize, n;
377

    
378
    /* left part */
379
    if (s->block_len_bits <= s->prev_block_len_bits) {
380
        block_len = s->block_len;
381
        bsize = s->frame_len_bits - s->block_len_bits;
382

    
383
        s->dsp.vector_fmul_add(out, in, s->windows[bsize],
384
                               out, block_len);
385

    
386
    } else {
387
        block_len = 1 << s->prev_block_len_bits;
388
        n = (s->block_len - block_len) / 2;
389
        bsize = s->frame_len_bits - s->prev_block_len_bits;
390

    
391
        s->dsp.vector_fmul_add(out+n, in+n, s->windows[bsize],
392
                               out+n, block_len);
393

    
394
        memcpy(out+n+block_len, in+n+block_len, n*sizeof(float));
395
    }
396

    
397
    out += s->block_len;
398
    in += s->block_len;
399

    
400
    /* right part */
401
    if (s->block_len_bits <= s->next_block_len_bits) {
402
        block_len = s->block_len;
403
        bsize = s->frame_len_bits - s->block_len_bits;
404

    
405
        s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len);
406

    
407
    } else {
408
        block_len = 1 << s->next_block_len_bits;
409
        n = (s->block_len - block_len) / 2;
410
        bsize = s->frame_len_bits - s->next_block_len_bits;
411

    
412
        memcpy(out, in, n*sizeof(float));
413

    
414
        s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len);
415

    
416
        memset(out+n+block_len, 0, n*sizeof(float));
417
    }
418
}
419

    
420

    
421
/**
422
 * @return 0 if OK. 1 if last block of frame. return -1 if
423
 * unrecorrable error.
424
 */
425
static int wma_decode_block(WMACodecContext *s)
426
{
427
    int n, v, a, ch, bsize;
428
    int coef_nb_bits, total_gain;
429
    int nb_coefs[MAX_CHANNELS];
430
    float mdct_norm;
431

    
432
#ifdef TRACE
433
    tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
434
#endif
435

    
436
    /* compute current block length */
437
    if (s->use_variable_block_len) {
438
        n = av_log2(s->nb_block_sizes - 1) + 1;
439

    
440
        if (s->reset_block_lengths) {
441
            s->reset_block_lengths = 0;
442
            v = get_bits(&s->gb, n);
443
            if (v >= s->nb_block_sizes)
444
                return -1;
445
            s->prev_block_len_bits = s->frame_len_bits - v;
446
            v = get_bits(&s->gb, n);
447
            if (v >= s->nb_block_sizes)
448
                return -1;
449
            s->block_len_bits = s->frame_len_bits - v;
450
        } else {
451
            /* update block lengths */
452
            s->prev_block_len_bits = s->block_len_bits;
453
            s->block_len_bits = s->next_block_len_bits;
454
        }
455
        v = get_bits(&s->gb, n);
456
        if (v >= s->nb_block_sizes)
457
            return -1;
458
        s->next_block_len_bits = s->frame_len_bits - v;
459
    } else {
460
        /* fixed block len */
461
        s->next_block_len_bits = s->frame_len_bits;
462
        s->prev_block_len_bits = s->frame_len_bits;
463
        s->block_len_bits = s->frame_len_bits;
464
    }
465

    
466
    /* now check if the block length is coherent with the frame length */
467
    s->block_len = 1 << s->block_len_bits;
468
    if ((s->block_pos + s->block_len) > s->frame_len)
469
        return -1;
470

    
471
    if (s->nb_channels == 2) {
472
        s->ms_stereo = get_bits1(&s->gb);
473
    }
474
    v = 0;
475
    for(ch = 0; ch < s->nb_channels; ch++) {
476
        a = get_bits1(&s->gb);
477
        s->channel_coded[ch] = a;
478
        v |= a;
479
    }
480

    
481
    bsize = s->frame_len_bits - s->block_len_bits;
482

    
483
    /* if no channel coded, no need to go further */
484
    /* XXX: fix potential framing problems */
485
    if (!v)
486
        goto next;
487

    
488
    /* read total gain and extract corresponding number of bits for
489
       coef escape coding */
490
    total_gain = 1;
491
    for(;;) {
492
        a = get_bits(&s->gb, 7);
493
        total_gain += a;
494
        if (a != 127)
495
            break;
496
    }
497

    
498
    coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
499

    
500
    /* compute number of coefficients */
501
    n = s->coefs_end[bsize] - s->coefs_start;
502
    for(ch = 0; ch < s->nb_channels; ch++)
503
        nb_coefs[ch] = n;
504

    
505
    /* complex coding */
506
    if (s->use_noise_coding) {
507

    
508
        for(ch = 0; ch < s->nb_channels; ch++) {
509
            if (s->channel_coded[ch]) {
510
                int i, n, a;
511
                n = s->exponent_high_sizes[bsize];
512
                for(i=0;i<n;i++) {
513
                    a = get_bits1(&s->gb);
514
                    s->high_band_coded[ch][i] = a;
515
                    /* if noise coding, the coefficients are not transmitted */
516
                    if (a)
517
                        nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
518
                }
519
            }
520
        }
521
        for(ch = 0; ch < s->nb_channels; ch++) {
522
            if (s->channel_coded[ch]) {
523
                int i, n, val, code;
524

    
525
                n = s->exponent_high_sizes[bsize];
526
                val = (int)0x80000000;
527
                for(i=0;i<n;i++) {
528
                    if (s->high_band_coded[ch][i]) {
529
                        if (val == (int)0x80000000) {
530
                            val = get_bits(&s->gb, 7) - 19;
531
                        } else {
532
                            code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX);
533
                            if (code < 0)
534
                                return -1;
535
                            val += code - 18;
536
                        }
537
                        s->high_band_values[ch][i] = val;
538
                    }
539
                }
540
            }
541
        }
542
    }
543

    
544
    /* exponents can be reused in short blocks. */
545
    if ((s->block_len_bits == s->frame_len_bits) ||
546
        get_bits1(&s->gb)) {
547
        for(ch = 0; ch < s->nb_channels; ch++) {
548
            if (s->channel_coded[ch]) {
549
                if (s->use_exp_vlc) {
550
                    if (decode_exp_vlc(s, ch) < 0)
551
                        return -1;
552
                } else {
553
                    decode_exp_lsp(s, ch);
554
                }
555
                s->exponents_bsize[ch] = bsize;
556
            }
557
        }
558
    }
559

    
560
    /* parse spectral coefficients : just RLE encoding */
561
    for(ch = 0; ch < s->nb_channels; ch++) {
562
        if (s->channel_coded[ch]) {
563
            int tindex;
564
            WMACoef* ptr = &s->coefs1[ch][0];
565

    
566
            /* special VLC tables are used for ms stereo because
567
               there is potentially less energy there */
568
            tindex = (ch == 1 && s->ms_stereo);
569
            memset(ptr, 0, s->block_len * sizeof(WMACoef));
570
            ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex],
571
                  s->level_table[tindex], s->run_table[tindex],
572
                  0, ptr, 0, nb_coefs[ch],
573
                  s->block_len, s->frame_len_bits, coef_nb_bits);
574
        }
575
        if (s->version == 1 && s->nb_channels >= 2) {
576
            align_get_bits(&s->gb);
577
        }
578
    }
579

    
580
    /* normalize */
581
    {
582
        int n4 = s->block_len / 2;
583
        mdct_norm = 1.0 / (float)n4;
584
        if (s->version == 1) {
585
            mdct_norm *= sqrt(n4);
586
        }
587
    }
588

    
589
    /* finally compute the MDCT coefficients */
590
    for(ch = 0; ch < s->nb_channels; ch++) {
591
        if (s->channel_coded[ch]) {
592
            WMACoef *coefs1;
593
            float *coefs, *exponents, mult, mult1, noise;
594
            int i, j, n, n1, last_high_band, esize;
595
            float exp_power[HIGH_BAND_MAX_SIZE];
596

    
597
            coefs1 = s->coefs1[ch];
598
            exponents = s->exponents[ch];
599
            esize = s->exponents_bsize[ch];
600
            mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
601
            mult *= mdct_norm;
602
            coefs = s->coefs[ch];
603
            if (s->use_noise_coding) {
604
                mult1 = mult;
605
                /* very low freqs : noise */
606
                for(i = 0;i < s->coefs_start; i++) {
607
                    *coefs++ = s->noise_table[s->noise_index] *
608
                      exponents[i<<bsize>>esize] * mult1;
609
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
610
                }
611

    
612
                n1 = s->exponent_high_sizes[bsize];
613

    
614
                /* compute power of high bands */
615
                exponents = s->exponents[ch] +
616
                    (s->high_band_start[bsize]<<bsize);
617
                last_high_band = 0; /* avoid warning */
618
                for(j=0;j<n1;j++) {
619
                    n = s->exponent_high_bands[s->frame_len_bits -
620
                                              s->block_len_bits][j];
621
                    if (s->high_band_coded[ch][j]) {
622
                        float e2, v;
623
                        e2 = 0;
624
                        for(i = 0;i < n; i++) {
625
                            v = exponents[i<<bsize>>esize];
626
                            e2 += v * v;
627
                        }
628
                        exp_power[j] = e2 / n;
629
                        last_high_band = j;
630
                        tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n);
631
                    }
632
                    exponents += n<<bsize;
633
                }
634

    
635
                /* main freqs and high freqs */
636
                exponents = s->exponents[ch] + (s->coefs_start<<bsize);
637
                for(j=-1;j<n1;j++) {
638
                    if (j < 0) {
639
                        n = s->high_band_start[bsize] -
640
                            s->coefs_start;
641
                    } else {
642
                        n = s->exponent_high_bands[s->frame_len_bits -
643
                                                  s->block_len_bits][j];
644
                    }
645
                    if (j >= 0 && s->high_band_coded[ch][j]) {
646
                        /* use noise with specified power */
647
                        mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
648
                        /* XXX: use a table */
649
                        mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
650
                        mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
651
                        mult1 *= mdct_norm;
652
                        for(i = 0;i < n; i++) {
653
                            noise = s->noise_table[s->noise_index];
654
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
655
                            *coefs++ =  noise *
656
                                exponents[i<<bsize>>esize] * mult1;
657
                        }
658
                        exponents += n<<bsize;
659
                    } else {
660
                        /* coded values + small noise */
661
                        for(i = 0;i < n; i++) {
662
                            noise = s->noise_table[s->noise_index];
663
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
664
                            *coefs++ = ((*coefs1++) + noise) *
665
                                exponents[i<<bsize>>esize] * mult;
666
                        }
667
                        exponents += n<<bsize;
668
                    }
669
                }
670

    
671
                /* very high freqs : noise */
672
                n = s->block_len - s->coefs_end[bsize];
673
                mult1 = mult * exponents[((-1<<bsize))>>esize];
674
                for(i = 0; i < n; i++) {
675
                    *coefs++ = s->noise_table[s->noise_index] * mult1;
676
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
677
                }
678
            } else {
679
                /* XXX: optimize more */
680
                for(i = 0;i < s->coefs_start; i++)
681
                    *coefs++ = 0.0;
682
                n = nb_coefs[ch];
683
                for(i = 0;i < n; i++) {
684
                    *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult;
685
                }
686
                n = s->block_len - s->coefs_end[bsize];
687
                for(i = 0;i < n; i++)
688
                    *coefs++ = 0.0;
689
            }
690
        }
691
    }
692

    
693
#ifdef TRACE
694
    for(ch = 0; ch < s->nb_channels; ch++) {
695
        if (s->channel_coded[ch]) {
696
            dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len);
697
            dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len);
698
        }
699
    }
700
#endif
701

    
702
    if (s->ms_stereo && s->channel_coded[1]) {
703
        /* nominal case for ms stereo: we do it before mdct */
704
        /* no need to optimize this case because it should almost
705
           never happen */
706
        if (!s->channel_coded[0]) {
707
            tprintf(s->avctx, "rare ms-stereo case happened\n");
708
            memset(s->coefs[0], 0, sizeof(float) * s->block_len);
709
            s->channel_coded[0] = 1;
710
        }
711

    
712
        s->dsp.butterflies_float(s->coefs[0], s->coefs[1], s->block_len);
713
    }
714

    
715
next:
716
    for(ch = 0; ch < s->nb_channels; ch++) {
717
        int n4, index;
718

    
719
        n4 = s->block_len / 2;
720
        if(s->channel_coded[ch]){
721
            ff_imdct_calc(&s->mdct_ctx[bsize], s->output, s->coefs[ch]);
722
        }else if(!(s->ms_stereo && ch==1))
723
            memset(s->output, 0, sizeof(s->output));
724

    
725
        /* multiply by the window and add in the frame */
726
        index = (s->frame_len / 2) + s->block_pos - n4;
727
        wma_window(s, &s->frame_out[ch][index]);
728
    }
729

    
730
    /* update block number */
731
    s->block_num++;
732
    s->block_pos += s->block_len;
733
    if (s->block_pos >= s->frame_len)
734
        return 1;
735
    else
736
        return 0;
737
}
738

    
739
/* decode a frame of frame_len samples */
740
static int wma_decode_frame(WMACodecContext *s, int16_t *samples)
741
{
742
    int ret, i, n, ch, incr;
743
    int16_t *ptr;
744
    float *iptr;
745

    
746
#ifdef TRACE
747
    tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
748
#endif
749

    
750
    /* read each block */
751
    s->block_num = 0;
752
    s->block_pos = 0;
753
    for(;;) {
754
        ret = wma_decode_block(s);
755
        if (ret < 0)
756
            return -1;
757
        if (ret)
758
            break;
759
    }
760

    
761
    /* convert frame to integer */
762
    n = s->frame_len;
763
    incr = s->nb_channels;
764
    for(ch = 0; ch < s->nb_channels; ch++) {
765
        ptr = samples + ch;
766
        iptr = s->frame_out[ch];
767

    
768
        for(i=0;i<n;i++) {
769
            *ptr = av_clip_int16(lrintf(*iptr++));
770
            ptr += incr;
771
        }
772
        /* prepare for next block */
773
        memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
774
                s->frame_len * sizeof(float));
775
    }
776

    
777
#ifdef TRACE
778
    dump_shorts(s, "samples", samples, n * s->nb_channels);
779
#endif
780
    return 0;
781
}
782

    
783
static int wma_decode_superframe(AVCodecContext *avctx,
784
                                 void *data, int *data_size,
785
                                 AVPacket *avpkt)
786
{
787
    const uint8_t *buf = avpkt->data;
788
    int buf_size = avpkt->size;
789
    WMACodecContext *s = avctx->priv_data;
790
    int nb_frames, bit_offset, i, pos, len;
791
    uint8_t *q;
792
    int16_t *samples;
793

    
794
    tprintf(avctx, "***decode_superframe:\n");
795

    
796
    if(buf_size==0){
797
        s->last_superframe_len = 0;
798
        return 0;
799
    }
800
    if (buf_size < s->block_align)
801
        return 0;
802
    buf_size = s->block_align;
803

    
804
    samples = data;
805

    
806
    init_get_bits(&s->gb, buf, buf_size*8);
807

    
808
    if (s->use_bit_reservoir) {
809
        /* read super frame header */
810
        skip_bits(&s->gb, 4); /* super frame index */
811
        nb_frames = get_bits(&s->gb, 4) - 1;
812

    
813
        if((nb_frames+1) * s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
814
            av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
815
            goto fail;
816
        }
817

    
818
        bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
819

    
820
        if (s->last_superframe_len > 0) {
821
            //        printf("skip=%d\n", s->last_bitoffset);
822
            /* add bit_offset bits to last frame */
823
            if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
824
                MAX_CODED_SUPERFRAME_SIZE)
825
                goto fail;
826
            q = s->last_superframe + s->last_superframe_len;
827
            len = bit_offset;
828
            while (len > 7) {
829
                *q++ = (get_bits)(&s->gb, 8);
830
                len -= 8;
831
            }
832
            if (len > 0) {
833
                *q++ = (get_bits)(&s->gb, len) << (8 - len);
834
            }
835

    
836
            /* XXX: bit_offset bits into last frame */
837
            init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8);
838
            /* skip unused bits */
839
            if (s->last_bitoffset > 0)
840
                skip_bits(&s->gb, s->last_bitoffset);
841
            /* this frame is stored in the last superframe and in the
842
               current one */
843
            if (wma_decode_frame(s, samples) < 0)
844
                goto fail;
845
            samples += s->nb_channels * s->frame_len;
846
        }
847

    
848
        /* read each frame starting from bit_offset */
849
        pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
850
        init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8);
851
        len = pos & 7;
852
        if (len > 0)
853
            skip_bits(&s->gb, len);
854

    
855
        s->reset_block_lengths = 1;
856
        for(i=0;i<nb_frames;i++) {
857
            if (wma_decode_frame(s, samples) < 0)
858
                goto fail;
859
            samples += s->nb_channels * s->frame_len;
860
        }
861

    
862
        /* we copy the end of the frame in the last frame buffer */
863
        pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
864
        s->last_bitoffset = pos & 7;
865
        pos >>= 3;
866
        len = buf_size - pos;
867
        if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
868
            goto fail;
869
        }
870
        s->last_superframe_len = len;
871
        memcpy(s->last_superframe, buf + pos, len);
872
    } else {
873
        if(s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
874
            av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
875
            goto fail;
876
        }
877
        /* single frame decode */
878
        if (wma_decode_frame(s, samples) < 0)
879
            goto fail;
880
        samples += s->nb_channels * s->frame_len;
881
    }
882

    
883
//av_log(NULL, AV_LOG_ERROR, "%d %d %d %d outbytes:%d eaten:%d\n", s->frame_len_bits, s->block_len_bits, s->frame_len, s->block_len,        (int8_t *)samples - (int8_t *)data, s->block_align);
884

    
885
    *data_size = (int8_t *)samples - (int8_t *)data;
886
    return s->block_align;
887
 fail:
888
    /* when error, we reset the bit reservoir */
889
    s->last_superframe_len = 0;
890
    return -1;
891
}
892

    
893
AVCodec wmav1_decoder =
894
{
895
    "wmav1",
896
    CODEC_TYPE_AUDIO,
897
    CODEC_ID_WMAV1,
898
    sizeof(WMACodecContext),
899
    wma_decode_init,
900
    NULL,
901
    ff_wma_end,
902
    wma_decode_superframe,
903
    .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
904
};
905

    
906
AVCodec wmav2_decoder =
907
{
908
    "wmav2",
909
    CODEC_TYPE_AUDIO,
910
    CODEC_ID_WMAV2,
911
    sizeof(WMACodecContext),
912
    wma_decode_init,
913
    NULL,
914
    ff_wma_end,
915
    wma_decode_superframe,
916
    .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
917
};