Statistics
| Branch: | Revision:

ffmpeg / libavcodec / wmadec.c @ 8b4a6d47

History | View | Annotate | Download (30 KB)

1
/*
2
 * WMA compatible decoder
3
 * Copyright (c) 2002 The FFmpeg Project
4
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * 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
 *
12
 * 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
 *
17
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21

    
22
/**
23
 * @file libavcodec/wmadec.c
24
 * WMA compatible decoder.
25
 * This decoder handles Microsoft Windows Media Audio data, versions 1 & 2.
26
 * WMA v1 is identified by audio format 0x160 in Microsoft media files
27
 * (ASF/AVI/WAV). WMA v2 is identified by audio format 0x161.
28
 *
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
31
 * 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..95 */
244
static const float pow_tab[] = {
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
    1.7782794100389e+04, 2.0535250264571e+04,
310
    2.3713737056617e+04, 2.7384196342644e+04,
311
    3.1622776601684e+04, 3.6517412725484e+04,
312
    4.2169650342858e+04, 4.8696752516586e+04,
313
    5.6234132519035e+04, 6.4938163157621e+04,
314
    7.4989420933246e+04, 8.6596432336007e+04,
315
    1.0000000000000e+05, 1.1547819846895e+05,
316
    1.3335214321633e+05, 1.5399265260595e+05,
317
    1.7782794100389e+05, 2.0535250264571e+05,
318
    2.3713737056617e+05, 2.7384196342644e+05,
319
    3.1622776601684e+05, 3.6517412725484e+05,
320
    4.2169650342858e+05, 4.8696752516586e+05,
321
    5.6234132519035e+05, 6.4938163157621e+05,
322
    7.4989420933246e+05, 8.6596432336007e+05,
323
};
324

    
325
/**
326
 * decode exponents coded with VLC codes
327
 */
328
static int decode_exp_vlc(WMACodecContext *s, int ch)
329
{
330
    int last_exp, n, code;
331
    const uint16_t *ptr;
332
    float v, max_scale;
333
    uint32_t *q, *q_end, iv;
334
    const float *ptab = pow_tab + 60;
335
    const uint32_t *iptab = (const uint32_t*)ptab;
336

    
337
    ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
338
    q = (uint32_t *)s->exponents[ch];
339
    q_end = q + s->block_len;
340
    max_scale = 0;
341
    if (s->version == 1) {
342
        last_exp = get_bits(&s->gb, 5) + 10;
343
        v = ptab[last_exp];
344
        iv = iptab[last_exp];
345
        max_scale = v;
346
        n = *ptr++;
347
        switch (n & 3) do {
348
        case 0: *q++ = iv;
349
        case 3: *q++ = iv;
350
        case 2: *q++ = iv;
351
        case 1: *q++ = iv;
352
        } while ((n -= 4) > 0);
353
    }else
354
        last_exp = 36;
355

    
356
    while (q < q_end) {
357
        code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
358
        if (code < 0)
359
            return -1;
360
        /* NOTE: this offset is the same as MPEG4 AAC ! */
361
        last_exp += code - 60;
362
        if ((unsigned)last_exp + 60 > FF_ARRAY_ELEMS(pow_tab)) {
363
            av_log(s->avctx, AV_LOG_ERROR, "Exponent out of range: %d\n",
364
                   last_exp);
365
            return -1;
366
        }
367
        v = ptab[last_exp];
368
        iv = iptab[last_exp];
369
        if (v > max_scale)
370
            max_scale = v;
371
        n = *ptr++;
372
        switch (n & 3) do {
373
        case 0: *q++ = iv;
374
        case 3: *q++ = iv;
375
        case 2: *q++ = iv;
376
        case 1: *q++ = iv;
377
        } while ((n -= 4) > 0);
378
    }
379
    s->max_exponent[ch] = max_scale;
380
    return 0;
381
}
382

    
383

    
384
/**
385
 * Apply MDCT window and add into output.
386
 *
387
 * We ensure that when the windows overlap their squared sum
388
 * is always 1 (MDCT reconstruction rule).
389
 */
390
static void wma_window(WMACodecContext *s, float *out)
391
{
392
    float *in = s->output;
393
    int block_len, bsize, n;
394

    
395
    /* left part */
396
    if (s->block_len_bits <= s->prev_block_len_bits) {
397
        block_len = s->block_len;
398
        bsize = s->frame_len_bits - s->block_len_bits;
399

    
400
        s->dsp.vector_fmul_add(out, in, s->windows[bsize],
401
                               out, block_len);
402

    
403
    } else {
404
        block_len = 1 << s->prev_block_len_bits;
405
        n = (s->block_len - block_len) / 2;
406
        bsize = s->frame_len_bits - s->prev_block_len_bits;
407

    
408
        s->dsp.vector_fmul_add(out+n, in+n, s->windows[bsize],
409
                               out+n, block_len);
410

    
411
        memcpy(out+n+block_len, in+n+block_len, n*sizeof(float));
412
    }
413

    
414
    out += s->block_len;
415
    in += s->block_len;
416

    
417
    /* right part */
418
    if (s->block_len_bits <= s->next_block_len_bits) {
419
        block_len = s->block_len;
420
        bsize = s->frame_len_bits - s->block_len_bits;
421

    
422
        s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len);
423

    
424
    } else {
425
        block_len = 1 << s->next_block_len_bits;
426
        n = (s->block_len - block_len) / 2;
427
        bsize = s->frame_len_bits - s->next_block_len_bits;
428

    
429
        memcpy(out, in, n*sizeof(float));
430

    
431
        s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len);
432

    
433
        memset(out+n+block_len, 0, n*sizeof(float));
434
    }
435
}
436

    
437

    
438
/**
439
 * @return 0 if OK. 1 if last block of frame. return -1 if
440
 * unrecorrable error.
441
 */
442
static int wma_decode_block(WMACodecContext *s)
443
{
444
    int n, v, a, ch, bsize;
445
    int coef_nb_bits, total_gain;
446
    int nb_coefs[MAX_CHANNELS];
447
    float mdct_norm;
448

    
449
#ifdef TRACE
450
    tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
451
#endif
452

    
453
    /* compute current block length */
454
    if (s->use_variable_block_len) {
455
        n = av_log2(s->nb_block_sizes - 1) + 1;
456

    
457
        if (s->reset_block_lengths) {
458
            s->reset_block_lengths = 0;
459
            v = get_bits(&s->gb, n);
460
            if (v >= s->nb_block_sizes)
461
                return -1;
462
            s->prev_block_len_bits = s->frame_len_bits - v;
463
            v = get_bits(&s->gb, n);
464
            if (v >= s->nb_block_sizes)
465
                return -1;
466
            s->block_len_bits = s->frame_len_bits - v;
467
        } else {
468
            /* update block lengths */
469
            s->prev_block_len_bits = s->block_len_bits;
470
            s->block_len_bits = s->next_block_len_bits;
471
        }
472
        v = get_bits(&s->gb, n);
473
        if (v >= s->nb_block_sizes)
474
            return -1;
475
        s->next_block_len_bits = s->frame_len_bits - v;
476
    } else {
477
        /* fixed block len */
478
        s->next_block_len_bits = s->frame_len_bits;
479
        s->prev_block_len_bits = s->frame_len_bits;
480
        s->block_len_bits = s->frame_len_bits;
481
    }
482

    
483
    /* now check if the block length is coherent with the frame length */
484
    s->block_len = 1 << s->block_len_bits;
485
    if ((s->block_pos + s->block_len) > s->frame_len)
486
        return -1;
487

    
488
    if (s->nb_channels == 2) {
489
        s->ms_stereo = get_bits1(&s->gb);
490
    }
491
    v = 0;
492
    for(ch = 0; ch < s->nb_channels; ch++) {
493
        a = get_bits1(&s->gb);
494
        s->channel_coded[ch] = a;
495
        v |= a;
496
    }
497

    
498
    bsize = s->frame_len_bits - s->block_len_bits;
499

    
500
    /* if no channel coded, no need to go further */
501
    /* XXX: fix potential framing problems */
502
    if (!v)
503
        goto next;
504

    
505
    /* read total gain and extract corresponding number of bits for
506
       coef escape coding */
507
    total_gain = 1;
508
    for(;;) {
509
        a = get_bits(&s->gb, 7);
510
        total_gain += a;
511
        if (a != 127)
512
            break;
513
    }
514

    
515
    coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
516

    
517
    /* compute number of coefficients */
518
    n = s->coefs_end[bsize] - s->coefs_start;
519
    for(ch = 0; ch < s->nb_channels; ch++)
520
        nb_coefs[ch] = n;
521

    
522
    /* complex coding */
523
    if (s->use_noise_coding) {
524

    
525
        for(ch = 0; ch < s->nb_channels; ch++) {
526
            if (s->channel_coded[ch]) {
527
                int i, n, a;
528
                n = s->exponent_high_sizes[bsize];
529
                for(i=0;i<n;i++) {
530
                    a = get_bits1(&s->gb);
531
                    s->high_band_coded[ch][i] = a;
532
                    /* if noise coding, the coefficients are not transmitted */
533
                    if (a)
534
                        nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
535
                }
536
            }
537
        }
538
        for(ch = 0; ch < s->nb_channels; ch++) {
539
            if (s->channel_coded[ch]) {
540
                int i, n, val, code;
541

    
542
                n = s->exponent_high_sizes[bsize];
543
                val = (int)0x80000000;
544
                for(i=0;i<n;i++) {
545
                    if (s->high_band_coded[ch][i]) {
546
                        if (val == (int)0x80000000) {
547
                            val = get_bits(&s->gb, 7) - 19;
548
                        } else {
549
                            code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX);
550
                            if (code < 0)
551
                                return -1;
552
                            val += code - 18;
553
                        }
554
                        s->high_band_values[ch][i] = val;
555
                    }
556
                }
557
            }
558
        }
559
    }
560

    
561
    /* exponents can be reused in short blocks. */
562
    if ((s->block_len_bits == s->frame_len_bits) ||
563
        get_bits1(&s->gb)) {
564
        for(ch = 0; ch < s->nb_channels; ch++) {
565
            if (s->channel_coded[ch]) {
566
                if (s->use_exp_vlc) {
567
                    if (decode_exp_vlc(s, ch) < 0)
568
                        return -1;
569
                } else {
570
                    decode_exp_lsp(s, ch);
571
                }
572
                s->exponents_bsize[ch] = bsize;
573
            }
574
        }
575
    }
576

    
577
    /* parse spectral coefficients : just RLE encoding */
578
    for(ch = 0; ch < s->nb_channels; ch++) {
579
        if (s->channel_coded[ch]) {
580
            int tindex;
581
            WMACoef* ptr = &s->coefs1[ch][0];
582

    
583
            /* special VLC tables are used for ms stereo because
584
               there is potentially less energy there */
585
            tindex = (ch == 1 && s->ms_stereo);
586
            memset(ptr, 0, s->block_len * sizeof(WMACoef));
587
            ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex],
588
                  s->level_table[tindex], s->run_table[tindex],
589
                  0, ptr, 0, nb_coefs[ch],
590
                  s->block_len, s->frame_len_bits, coef_nb_bits);
591
        }
592
        if (s->version == 1 && s->nb_channels >= 2) {
593
            align_get_bits(&s->gb);
594
        }
595
    }
596

    
597
    /* normalize */
598
    {
599
        int n4 = s->block_len / 2;
600
        mdct_norm = 1.0 / (float)n4;
601
        if (s->version == 1) {
602
            mdct_norm *= sqrt(n4);
603
        }
604
    }
605

    
606
    /* finally compute the MDCT coefficients */
607
    for(ch = 0; ch < s->nb_channels; ch++) {
608
        if (s->channel_coded[ch]) {
609
            WMACoef *coefs1;
610
            float *coefs, *exponents, mult, mult1, noise;
611
            int i, j, n, n1, last_high_band, esize;
612
            float exp_power[HIGH_BAND_MAX_SIZE];
613

    
614
            coefs1 = s->coefs1[ch];
615
            exponents = s->exponents[ch];
616
            esize = s->exponents_bsize[ch];
617
            mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
618
            mult *= mdct_norm;
619
            coefs = s->coefs[ch];
620
            if (s->use_noise_coding) {
621
                mult1 = mult;
622
                /* very low freqs : noise */
623
                for(i = 0;i < s->coefs_start; i++) {
624
                    *coefs++ = s->noise_table[s->noise_index] *
625
                      exponents[i<<bsize>>esize] * mult1;
626
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
627
                }
628

    
629
                n1 = s->exponent_high_sizes[bsize];
630

    
631
                /* compute power of high bands */
632
                exponents = s->exponents[ch] +
633
                    (s->high_band_start[bsize]<<bsize);
634
                last_high_band = 0; /* avoid warning */
635
                for(j=0;j<n1;j++) {
636
                    n = s->exponent_high_bands[s->frame_len_bits -
637
                                              s->block_len_bits][j];
638
                    if (s->high_band_coded[ch][j]) {
639
                        float e2, v;
640
                        e2 = 0;
641
                        for(i = 0;i < n; i++) {
642
                            v = exponents[i<<bsize>>esize];
643
                            e2 += v * v;
644
                        }
645
                        exp_power[j] = e2 / n;
646
                        last_high_band = j;
647
                        tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n);
648
                    }
649
                    exponents += n<<bsize;
650
                }
651

    
652
                /* main freqs and high freqs */
653
                exponents = s->exponents[ch] + (s->coefs_start<<bsize);
654
                for(j=-1;j<n1;j++) {
655
                    if (j < 0) {
656
                        n = s->high_band_start[bsize] -
657
                            s->coefs_start;
658
                    } else {
659
                        n = s->exponent_high_bands[s->frame_len_bits -
660
                                                  s->block_len_bits][j];
661
                    }
662
                    if (j >= 0 && s->high_band_coded[ch][j]) {
663
                        /* use noise with specified power */
664
                        mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
665
                        /* XXX: use a table */
666
                        mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
667
                        mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
668
                        mult1 *= mdct_norm;
669
                        for(i = 0;i < n; i++) {
670
                            noise = s->noise_table[s->noise_index];
671
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
672
                            *coefs++ =  noise *
673
                                exponents[i<<bsize>>esize] * mult1;
674
                        }
675
                        exponents += n<<bsize;
676
                    } else {
677
                        /* coded values + small noise */
678
                        for(i = 0;i < n; i++) {
679
                            noise = s->noise_table[s->noise_index];
680
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
681
                            *coefs++ = ((*coefs1++) + noise) *
682
                                exponents[i<<bsize>>esize] * mult;
683
                        }
684
                        exponents += n<<bsize;
685
                    }
686
                }
687

    
688
                /* very high freqs : noise */
689
                n = s->block_len - s->coefs_end[bsize];
690
                mult1 = mult * exponents[((-1<<bsize))>>esize];
691
                for(i = 0; i < n; i++) {
692
                    *coefs++ = s->noise_table[s->noise_index] * mult1;
693
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
694
                }
695
            } else {
696
                /* XXX: optimize more */
697
                for(i = 0;i < s->coefs_start; i++)
698
                    *coefs++ = 0.0;
699
                n = nb_coefs[ch];
700
                for(i = 0;i < n; i++) {
701
                    *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult;
702
                }
703
                n = s->block_len - s->coefs_end[bsize];
704
                for(i = 0;i < n; i++)
705
                    *coefs++ = 0.0;
706
            }
707
        }
708
    }
709

    
710
#ifdef TRACE
711
    for(ch = 0; ch < s->nb_channels; ch++) {
712
        if (s->channel_coded[ch]) {
713
            dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len);
714
            dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len);
715
        }
716
    }
717
#endif
718

    
719
    if (s->ms_stereo && s->channel_coded[1]) {
720
        /* nominal case for ms stereo: we do it before mdct */
721
        /* no need to optimize this case because it should almost
722
           never happen */
723
        if (!s->channel_coded[0]) {
724
            tprintf(s->avctx, "rare ms-stereo case happened\n");
725
            memset(s->coefs[0], 0, sizeof(float) * s->block_len);
726
            s->channel_coded[0] = 1;
727
        }
728

    
729
        s->dsp.butterflies_float(s->coefs[0], s->coefs[1], s->block_len);
730
    }
731

    
732
next:
733
    for(ch = 0; ch < s->nb_channels; ch++) {
734
        int n4, index;
735

    
736
        n4 = s->block_len / 2;
737
        if(s->channel_coded[ch]){
738
            ff_imdct_calc(&s->mdct_ctx[bsize], s->output, s->coefs[ch]);
739
        }else if(!(s->ms_stereo && ch==1))
740
            memset(s->output, 0, sizeof(s->output));
741

    
742
        /* multiply by the window and add in the frame */
743
        index = (s->frame_len / 2) + s->block_pos - n4;
744
        wma_window(s, &s->frame_out[ch][index]);
745
    }
746

    
747
    /* update block number */
748
    s->block_num++;
749
    s->block_pos += s->block_len;
750
    if (s->block_pos >= s->frame_len)
751
        return 1;
752
    else
753
        return 0;
754
}
755

    
756
/* decode a frame of frame_len samples */
757
static int wma_decode_frame(WMACodecContext *s, int16_t *samples)
758
{
759
    int ret, i, n, ch, incr;
760
    int16_t *ptr;
761
    float *iptr;
762

    
763
#ifdef TRACE
764
    tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
765
#endif
766

    
767
    /* read each block */
768
    s->block_num = 0;
769
    s->block_pos = 0;
770
    for(;;) {
771
        ret = wma_decode_block(s);
772
        if (ret < 0)
773
            return -1;
774
        if (ret)
775
            break;
776
    }
777

    
778
    /* convert frame to integer */
779
    n = s->frame_len;
780
    incr = s->nb_channels;
781
    for(ch = 0; ch < s->nb_channels; ch++) {
782
        ptr = samples + ch;
783
        iptr = s->frame_out[ch];
784

    
785
        for(i=0;i<n;i++) {
786
            *ptr = av_clip_int16(lrintf(*iptr++));
787
            ptr += incr;
788
        }
789
        /* prepare for next block */
790
        memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
791
                s->frame_len * sizeof(float));
792
    }
793

    
794
#ifdef TRACE
795
    dump_shorts(s, "samples", samples, n * s->nb_channels);
796
#endif
797
    return 0;
798
}
799

    
800
static int wma_decode_superframe(AVCodecContext *avctx,
801
                                 void *data, int *data_size,
802
                                 AVPacket *avpkt)
803
{
804
    const uint8_t *buf = avpkt->data;
805
    int buf_size = avpkt->size;
806
    WMACodecContext *s = avctx->priv_data;
807
    int nb_frames, bit_offset, i, pos, len;
808
    uint8_t *q;
809
    int16_t *samples;
810

    
811
    tprintf(avctx, "***decode_superframe:\n");
812

    
813
    if(buf_size==0){
814
        s->last_superframe_len = 0;
815
        return 0;
816
    }
817
    if (buf_size < s->block_align)
818
        return 0;
819
    buf_size = s->block_align;
820

    
821
    samples = data;
822

    
823
    init_get_bits(&s->gb, buf, buf_size*8);
824

    
825
    if (s->use_bit_reservoir) {
826
        /* read super frame header */
827
        skip_bits(&s->gb, 4); /* super frame index */
828
        nb_frames = get_bits(&s->gb, 4) - 1;
829

    
830
        if((nb_frames+1) * s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
831
            av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
832
            goto fail;
833
        }
834

    
835
        bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
836

    
837
        if (s->last_superframe_len > 0) {
838
            //        printf("skip=%d\n", s->last_bitoffset);
839
            /* add bit_offset bits to last frame */
840
            if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
841
                MAX_CODED_SUPERFRAME_SIZE)
842
                goto fail;
843
            q = s->last_superframe + s->last_superframe_len;
844
            len = bit_offset;
845
            while (len > 7) {
846
                *q++ = (get_bits)(&s->gb, 8);
847
                len -= 8;
848
            }
849
            if (len > 0) {
850
                *q++ = (get_bits)(&s->gb, len) << (8 - len);
851
            }
852

    
853
            /* XXX: bit_offset bits into last frame */
854
            init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8);
855
            /* skip unused bits */
856
            if (s->last_bitoffset > 0)
857
                skip_bits(&s->gb, s->last_bitoffset);
858
            /* this frame is stored in the last superframe and in the
859
               current one */
860
            if (wma_decode_frame(s, samples) < 0)
861
                goto fail;
862
            samples += s->nb_channels * s->frame_len;
863
        }
864

    
865
        /* read each frame starting from bit_offset */
866
        pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
867
        init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8);
868
        len = pos & 7;
869
        if (len > 0)
870
            skip_bits(&s->gb, len);
871

    
872
        s->reset_block_lengths = 1;
873
        for(i=0;i<nb_frames;i++) {
874
            if (wma_decode_frame(s, samples) < 0)
875
                goto fail;
876
            samples += s->nb_channels * s->frame_len;
877
        }
878

    
879
        /* we copy the end of the frame in the last frame buffer */
880
        pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
881
        s->last_bitoffset = pos & 7;
882
        pos >>= 3;
883
        len = buf_size - pos;
884
        if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
885
            goto fail;
886
        }
887
        s->last_superframe_len = len;
888
        memcpy(s->last_superframe, buf + pos, len);
889
    } else {
890
        if(s->nb_channels * s->frame_len * sizeof(int16_t) > *data_size){
891
            av_log(s->avctx, AV_LOG_ERROR, "Insufficient output space\n");
892
            goto fail;
893
        }
894
        /* single frame decode */
895
        if (wma_decode_frame(s, samples) < 0)
896
            goto fail;
897
        samples += s->nb_channels * s->frame_len;
898
    }
899

    
900
//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);
901

    
902
    *data_size = (int8_t *)samples - (int8_t *)data;
903
    return s->block_align;
904
 fail:
905
    /* when error, we reset the bit reservoir */
906
    s->last_superframe_len = 0;
907
    return -1;
908
}
909

    
910
AVCodec wmav1_decoder =
911
{
912
    "wmav1",
913
    CODEC_TYPE_AUDIO,
914
    CODEC_ID_WMAV1,
915
    sizeof(WMACodecContext),
916
    wma_decode_init,
917
    NULL,
918
    ff_wma_end,
919
    wma_decode_superframe,
920
    .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
921
};
922

    
923
AVCodec wmav2_decoder =
924
{
925
    "wmav2",
926
    CODEC_TYPE_AUDIO,
927
    CODEC_ID_WMAV2,
928
    sizeof(WMACodecContext),
929
    wma_decode_init,
930
    NULL,
931
    ff_wma_end,
932
    wma_decode_superframe,
933
    .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
934
};