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1
/*
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 * WMA compatible decoder
3
 * Copyright (c) 2002 The FFmpeg Project.
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * 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,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * 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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 */
19

    
20
/**
21
 * @file wmadec.c
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 * WMA compatible decoder.
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 * 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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 *
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 * To use this decoder, a calling application must supply the extra data
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 * 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 
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 * to the decoder using the extradata[_size] fields in AVCodecContext. There 
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 * should be 4 extra bytes for v1 data and 6 extra bytes for v2 data.
32
 */
33

    
34
#include "avcodec.h"
35
#include "dsputil.h"
36

    
37
/* size of blocks */
38
#define BLOCK_MIN_BITS 7
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#define BLOCK_MAX_BITS 11
40
#define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
41

    
42
#define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
43

    
44
/* XXX: find exact max size */
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#define HIGH_BAND_MAX_SIZE 16
46

    
47
#define NB_LSP_COEFS 10
48

    
49
/* XXX: is it a suitable value ? */
50
#define MAX_CODED_SUPERFRAME_SIZE 4096
51

    
52
#define MAX_CHANNELS 2
53

    
54
#define NOISE_TAB_SIZE 8192
55

    
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#define LSP_POW_BITS 7
57

    
58
typedef struct WMADecodeContext {
59
    GetBitContext gb;
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    int sample_rate;
61
    int nb_channels;
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    int bit_rate;
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    int version; /* 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2) */
64
    int block_align;
65
    int use_bit_reservoir;
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    int use_variable_block_len;
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    int use_exp_vlc;  /* exponent coding: 0 = lsp, 1 = vlc + delta */
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    int use_noise_coding; /* true if perceptual noise is added */
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    int byte_offset_bits;
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    VLC exp_vlc;
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    int exponent_sizes[BLOCK_NB_SIZES];
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    uint16_t exponent_bands[BLOCK_NB_SIZES][25];
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    int high_band_start[BLOCK_NB_SIZES]; /* index of first coef in high band */
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    int coefs_start;               /* first coded coef */
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    int coefs_end[BLOCK_NB_SIZES]; /* max number of coded coefficients */
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    int exponent_high_sizes[BLOCK_NB_SIZES];
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    int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE]; 
78
    VLC hgain_vlc;
79
    
80
    /* coded values in high bands */
81
    int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
82
    int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
83

    
84
    /* there are two possible tables for spectral coefficients */
85
    VLC coef_vlc[2];
86
    uint16_t *run_table[2];
87
    uint16_t *level_table[2];
88
    /* frame info */
89
    int frame_len;       /* frame length in samples */
90
    int frame_len_bits;  /* frame_len = 1 << frame_len_bits */
91
    int nb_block_sizes;  /* number of block sizes */
92
    /* block info */
93
    int reset_block_lengths;
94
    int block_len_bits; /* log2 of current block length */
95
    int next_block_len_bits; /* log2 of next block length */
96
    int prev_block_len_bits; /* log2 of prev block length */
97
    int block_len; /* block length in samples */
98
    int block_num; /* block number in current frame */
99
    int block_pos; /* current position in frame */
100
    uint8_t ms_stereo; /* true if mid/side stereo mode */
101
    uint8_t channel_coded[MAX_CHANNELS]; /* true if channel is coded */
102
    float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE] __attribute__((aligned(16)));
103
    float max_exponent[MAX_CHANNELS];
104
    int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
105
    float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE] __attribute__((aligned(16)));
106
    MDCTContext mdct_ctx[BLOCK_NB_SIZES];
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    float *windows[BLOCK_NB_SIZES];
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    FFTSample mdct_tmp[BLOCK_MAX_SIZE] __attribute__((aligned(16))); /* temporary storage for imdct */
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    /* output buffer for one frame and the last for IMDCT windowing */
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    float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2] __attribute__((aligned(16)));
111
    /* last frame info */
112
    uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
113
    int last_bitoffset;
114
    int last_superframe_len;
115
    float noise_table[NOISE_TAB_SIZE];
116
    int noise_index;
117
    float noise_mult; /* XXX: suppress that and integrate it in the noise array */
118
    /* lsp_to_curve tables */
119
    float lsp_cos_table[BLOCK_MAX_SIZE];
120
    float lsp_pow_e_table[256];
121
    float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
122
    float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
123

    
124
#ifdef TRACE
125
    int frame_count;
126
#endif
127
} WMADecodeContext;
128

    
129
typedef struct CoefVLCTable {
130
    int n; /* total number of codes */
131
    const uint32_t *huffcodes; /* VLC bit values */
132
    const uint8_t *huffbits;   /* VLC bit size */
133
    const uint16_t *levels; /* table to build run/level tables */
134
} CoefVLCTable;
135

    
136
static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len);
137

    
138
#include "wmadata.h"
139

    
140
#ifdef TRACE
141
static void dump_shorts(const char *name, const short *tab, int n)
142
{
143
    int i;
144

    
145
    tprintf("%s[%d]:\n", name, n);
146
    for(i=0;i<n;i++) {
147
        if ((i & 7) == 0)
148
            tprintf("%4d: ", i);
149
        tprintf(" %5d.0", tab[i]);
150
        if ((i & 7) == 7)
151
            tprintf("\n");
152
    }
153
}
154

    
155
static void dump_floats(const char *name, int prec, const float *tab, int n)
156
{
157
    int i;
158

    
159
    tprintf("%s[%d]:\n", name, n);
160
    for(i=0;i<n;i++) {
161
        if ((i & 7) == 0)
162
            tprintf("%4d: ", i);
163
        tprintf(" %8.*f", prec, tab[i]);
164
        if ((i & 7) == 7)
165
            tprintf("\n");
166
    }
167
    if ((i & 7) != 0)
168
        tprintf("\n");
169
}
170
#endif
171

    
172
/* XXX: use same run/length optimization as mpeg decoders */
173
static void init_coef_vlc(VLC *vlc, 
174
                          uint16_t **prun_table, uint16_t **plevel_table,
175
                          const CoefVLCTable *vlc_table)
176
{
177
    int n = vlc_table->n;
178
    const uint8_t *table_bits = vlc_table->huffbits;
179
    const uint32_t *table_codes = vlc_table->huffcodes;
180
    const uint16_t *levels_table = vlc_table->levels;
181
    uint16_t *run_table, *level_table;
182
    const uint16_t *p;
183
    int i, l, j, level;
184

    
185
    init_vlc(vlc, 9, n, table_bits, 1, 1, table_codes, 4, 4);
186

    
187
    run_table = av_malloc(n * sizeof(uint16_t));
188
    level_table = av_malloc(n * sizeof(uint16_t));
189
    p = levels_table;
190
    i = 2;
191
    level = 1;
192
    while (i < n) {
193
        l = *p++;
194
        for(j=0;j<l;j++) {
195
            run_table[i] = j;
196
            level_table[i] = level;
197
            i++;
198
        }
199
        level++;
200
    }
201
    *prun_table = run_table;
202
    *plevel_table = level_table;
203
}
204

    
205
static int wma_decode_init(AVCodecContext * avctx)
206
{
207
    WMADecodeContext *s = avctx->priv_data;
208
    int i, flags1, flags2;
209
    float *window;
210
    uint8_t *extradata;
211
    float bps1, high_freq;
212
    volatile float bps;
213
    int sample_rate1;
214
    int coef_vlc_table;
215
    
216
    s->sample_rate = avctx->sample_rate;
217
    s->nb_channels = avctx->channels;
218
    s->bit_rate = avctx->bit_rate;
219
    s->block_align = avctx->block_align;
220

    
221
    if (avctx->codec->id == CODEC_ID_WMAV1) {
222
        s->version = 1;
223
    } else {
224
        s->version = 2;
225
    }
226
    
227
    /* extract flag infos */
228
    flags1 = 0;
229
    flags2 = 0;
230
    extradata = avctx->extradata;
231
    if (s->version == 1 && avctx->extradata_size >= 4) {
232
        flags1 = extradata[0] | (extradata[1] << 8);
233
        flags2 = extradata[2] | (extradata[3] << 8);
234
    } else if (s->version == 2 && avctx->extradata_size >= 6) {
235
        flags1 = extradata[0] | (extradata[1] << 8) | 
236
            (extradata[2] << 16) | (extradata[3] << 24);
237
        flags2 = extradata[4] | (extradata[5] << 8);
238
    }
239
    s->use_exp_vlc = flags2 & 0x0001;
240
    s->use_bit_reservoir = flags2 & 0x0002;
241
    s->use_variable_block_len = flags2 & 0x0004;
242

    
243
    /* compute MDCT block size */
244
    if (s->sample_rate <= 16000) {
245
        s->frame_len_bits = 9;
246
    } else if (s->sample_rate <= 22050 || 
247
               (s->sample_rate <= 32000 && s->version == 1)) {
248
        s->frame_len_bits = 10;
249
    } else {
250
        s->frame_len_bits = 11;
251
    }
252
    s->frame_len = 1 << s->frame_len_bits;
253
    if (s->use_variable_block_len) {
254
        int nb_max, nb;
255
        nb = ((flags2 >> 3) & 3) + 1;
256
        if ((s->bit_rate / s->nb_channels) >= 32000)
257
            nb += 2;
258
        nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
259
        if (nb > nb_max)
260
            nb = nb_max;
261
        s->nb_block_sizes = nb + 1;
262
    } else {
263
        s->nb_block_sizes = 1;
264
    }
265

    
266
    /* init rate dependant parameters */
267
    s->use_noise_coding = 1;
268
    high_freq = s->sample_rate * 0.5;
269

    
270
    /* if version 2, then the rates are normalized */
271
    sample_rate1 = s->sample_rate;
272
    if (s->version == 2) {
273
        if (sample_rate1 >= 44100) 
274
            sample_rate1 = 44100;
275
        else if (sample_rate1 >= 22050) 
276
            sample_rate1 = 22050;
277
        else if (sample_rate1 >= 16000) 
278
            sample_rate1 = 16000;
279
        else if (sample_rate1 >= 11025) 
280
            sample_rate1 = 11025;
281
        else if (sample_rate1 >= 8000) 
282
            sample_rate1 = 8000;
283
    }
284

    
285
    bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
286
    s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0)) + 2;
287

    
288
    /* compute high frequency value and choose if noise coding should
289
       be activated */
290
    bps1 = bps;
291
    if (s->nb_channels == 2)
292
        bps1 = bps * 1.6;
293
    if (sample_rate1 == 44100) {
294
        if (bps1 >= 0.61)
295
            s->use_noise_coding = 0;
296
        else
297
            high_freq = high_freq * 0.4;
298
    } else if (sample_rate1 == 22050) {
299
        if (bps1 >= 1.16)
300
            s->use_noise_coding = 0;
301
        else if (bps1 >= 0.72) 
302
            high_freq = high_freq * 0.7;
303
        else
304
            high_freq = high_freq * 0.6;
305
    } else if (sample_rate1 == 16000) {
306
        if (bps > 0.5)
307
            high_freq = high_freq * 0.5;
308
        else
309
            high_freq = high_freq * 0.3;
310
    } else if (sample_rate1 == 11025) {
311
        high_freq = high_freq * 0.7;
312
    } else if (sample_rate1 == 8000) {
313
        if (bps <= 0.625) {
314
            high_freq = high_freq * 0.5;
315
        } else if (bps > 0.75) {
316
            s->use_noise_coding = 0;
317
        } else {
318
            high_freq = high_freq * 0.65;
319
        }
320
    } else {
321
        if (bps >= 0.8) {
322
            high_freq = high_freq * 0.75;
323
        } else if (bps >= 0.6) {
324
            high_freq = high_freq * 0.6;
325
        } else {
326
            high_freq = high_freq * 0.5;
327
        }
328
    }
329
    dprintf("flags1=0x%x flags2=0x%x\n", flags1, flags2);
330
    dprintf("version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
331
           s->version, s->nb_channels, s->sample_rate, s->bit_rate, 
332
           s->block_align);
333
    dprintf("bps=%f bps1=%f high_freq=%f bitoffset=%d\n", 
334
           bps, bps1, high_freq, s->byte_offset_bits);
335
    dprintf("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
336
           s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
337

    
338
    /* compute the scale factor band sizes for each MDCT block size */
339
    {
340
        int a, b, pos, lpos, k, block_len, i, j, n;
341
        const uint8_t *table;
342
        
343
        if (s->version == 1) {
344
            s->coefs_start = 3;
345
        } else {
346
            s->coefs_start = 0;
347
        }
348
        for(k = 0; k < s->nb_block_sizes; k++) {
349
            block_len = s->frame_len >> k;
350

    
351
            if (s->version == 1) {
352
                lpos = 0;
353
                for(i=0;i<25;i++) {
354
                    a = wma_critical_freqs[i];
355
                    b = s->sample_rate;
356
                    pos = ((block_len * 2 * a)  + (b >> 1)) / b;
357
                    if (pos > block_len) 
358
                        pos = block_len;
359
                    s->exponent_bands[0][i] = pos - lpos;
360
                    if (pos >= block_len) {
361
                        i++;
362
                        break;
363
                    }
364
                    lpos = pos;
365
                }
366
                s->exponent_sizes[0] = i;
367
            } else {
368
                /* hardcoded tables */
369
                table = NULL;
370
                a = s->frame_len_bits - BLOCK_MIN_BITS - k;
371
                if (a < 3) {
372
                    if (s->sample_rate >= 44100)
373
                        table = exponent_band_44100[a];
374
                    else if (s->sample_rate >= 32000)
375
                        table = exponent_band_32000[a];
376
                    else if (s->sample_rate >= 22050)
377
                        table = exponent_band_22050[a];
378
                }
379
                if (table) {
380
                    n = *table++;
381
                    for(i=0;i<n;i++)
382
                        s->exponent_bands[k][i] = table[i];
383
                    s->exponent_sizes[k] = n;
384
                } else {
385
                    j = 0;
386
                    lpos = 0;
387
                    for(i=0;i<25;i++) {
388
                        a = wma_critical_freqs[i];
389
                        b = s->sample_rate;
390
                        pos = ((block_len * 2 * a)  + (b << 1)) / (4 * b);
391
                        pos <<= 2;
392
                        if (pos > block_len) 
393
                            pos = block_len;
394
                        if (pos > lpos)
395
                            s->exponent_bands[k][j++] = pos - lpos;
396
                        if (pos >= block_len)
397
                            break;
398
                        lpos = pos;
399
                    }
400
                    s->exponent_sizes[k] = j;
401
                }
402
            }
403

    
404
            /* max number of coefs */
405
            s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
406
            /* high freq computation */
407
            s->high_band_start[k] = (int)((block_len * 2 * high_freq) / 
408
                                          s->sample_rate + 0.5);
409
            n = s->exponent_sizes[k];
410
            j = 0;
411
            pos = 0;
412
            for(i=0;i<n;i++) {
413
                int start, end;
414
                start = pos;
415
                pos += s->exponent_bands[k][i];
416
                end = pos;
417
                if (start < s->high_band_start[k])
418
                    start = s->high_band_start[k];
419
                if (end > s->coefs_end[k])
420
                    end = s->coefs_end[k];
421
                if (end > start)
422
                    s->exponent_high_bands[k][j++] = end - start;
423
            }
424
            s->exponent_high_sizes[k] = j;
425
#if 0
426
            tprintf("%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
427
                  s->frame_len >> k, 
428
                  s->coefs_end[k],
429
                  s->high_band_start[k],
430
                  s->exponent_high_sizes[k]);
431
            for(j=0;j<s->exponent_high_sizes[k];j++)
432
                tprintf(" %d", s->exponent_high_bands[k][j]);
433
            tprintf("\n");
434
#endif
435
        }
436
    }
437

    
438
#ifdef TRACE
439
    {
440
        int i, j;
441
        for(i = 0; i < s->nb_block_sizes; i++) {
442
            tprintf("%5d: n=%2d:", 
443
                   s->frame_len >> i, 
444
                   s->exponent_sizes[i]);
445
            for(j=0;j<s->exponent_sizes[i];j++)
446
                tprintf(" %d", s->exponent_bands[i][j]);
447
            tprintf("\n");
448
        }
449
    }
450
#endif
451

    
452
    /* init MDCT */
453
    for(i = 0; i < s->nb_block_sizes; i++)
454
        ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1);
455
    
456
    /* init MDCT windows : simple sinus window */
457
    for(i = 0; i < s->nb_block_sizes; i++) {
458
        int n, j;
459
        float alpha;
460
        n = 1 << (s->frame_len_bits - i);
461
        window = av_malloc(sizeof(float) * n);
462
        alpha = M_PI / (2.0 * n);
463
        for(j=0;j<n;j++) {
464
            window[n - j - 1] = sin((j + 0.5) * alpha);
465
        }
466
        s->windows[i] = window;
467
    }
468

    
469
    s->reset_block_lengths = 1;
470
    
471
    if (s->use_noise_coding) {
472

    
473
        /* init the noise generator */
474
        if (s->use_exp_vlc)
475
            s->noise_mult = 0.02;
476
        else
477
            s->noise_mult = 0.04;
478
               
479
#ifdef TRACE
480
        for(i=0;i<NOISE_TAB_SIZE;i++)
481
            s->noise_table[i] = 1.0 * s->noise_mult;
482
#else
483
        {
484
            unsigned int seed;
485
            float norm;
486
            seed = 1;
487
            norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
488
            for(i=0;i<NOISE_TAB_SIZE;i++) {
489
                seed = seed * 314159 + 1;
490
                s->noise_table[i] = (float)((int)seed) * norm;
491
            }
492
        }
493
#endif
494
        init_vlc(&s->hgain_vlc, 9, sizeof(hgain_huffbits), 
495
                 hgain_huffbits, 1, 1,
496
                 hgain_huffcodes, 2, 2);
497
    }
498

    
499
    if (s->use_exp_vlc) {
500
        init_vlc(&s->exp_vlc, 9, sizeof(scale_huffbits), 
501
                 scale_huffbits, 1, 1,
502
                 scale_huffcodes, 4, 4);
503
    } else {
504
        wma_lsp_to_curve_init(s, s->frame_len);
505
    }
506

    
507
    /* choose the VLC tables for the coefficients */
508
    coef_vlc_table = 2;
509
    if (s->sample_rate >= 32000) {
510
        if (bps1 < 0.72)
511
            coef_vlc_table = 0;
512
        else if (bps1 < 1.16)
513
            coef_vlc_table = 1;
514
    }
515

    
516
    init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
517
                  &coef_vlcs[coef_vlc_table * 2]);
518
    init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
519
                  &coef_vlcs[coef_vlc_table * 2 + 1]);
520
    return 0;
521
}
522

    
523
/* interpolate values for a bigger or smaller block. The block must
524
   have multiple sizes */
525
static void interpolate_array(float *scale, int old_size, int new_size)
526
{
527
    int i, j, jincr, k;
528
    float v;
529

    
530
    if (new_size > old_size) {
531
        jincr = new_size / old_size;
532
        j = new_size;
533
        for(i = old_size - 1; i >=0; i--) {
534
            v = scale[i];
535
            k = jincr;
536
            do {
537
                scale[--j] = v;
538
            } while (--k);
539
        }
540
    } else if (new_size < old_size) {
541
        j = 0;
542
        jincr = old_size / new_size;
543
        for(i = 0; i < new_size; i++) {
544
            scale[i] = scale[j];
545
            j += jincr;
546
        }
547
    }
548
}
549

    
550
/* compute x^-0.25 with an exponent and mantissa table. We use linear
551
   interpolation to reduce the mantissa table size at a small speed
552
   expense (linear interpolation approximately doubles the number of
553
   bits of precision). */
554
static inline float pow_m1_4(WMADecodeContext *s, float x)
555
{
556
    union {
557
        float f;
558
        unsigned int v;
559
    } u, t;
560
    unsigned int e, m;
561
    float a, b;
562

    
563
    u.f = x;
564
    e = u.v >> 23;
565
    m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
566
    /* build interpolation scale: 1 <= t < 2. */
567
    t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
568
    a = s->lsp_pow_m_table1[m];
569
    b = s->lsp_pow_m_table2[m];
570
    return s->lsp_pow_e_table[e] * (a + b * t.f);
571
}
572

    
573
static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len)
574
{  
575
    float wdel, a, b;
576
    int i, e, m;
577

    
578
    wdel = M_PI / frame_len;
579
    for(i=0;i<frame_len;i++)
580
        s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
581

    
582
    /* tables for x^-0.25 computation */
583
    for(i=0;i<256;i++) {
584
        e = i - 126;
585
        s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
586
    }
587

    
588
    /* NOTE: these two tables are needed to avoid two operations in
589
       pow_m1_4 */
590
    b = 1.0;
591
    for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
592
        m = (1 << LSP_POW_BITS) + i;
593
        a = (float)m * (0.5 / (1 << LSP_POW_BITS));
594
        a = pow(a, -0.25);
595
        s->lsp_pow_m_table1[i] = 2 * a - b;
596
        s->lsp_pow_m_table2[i] = b - a;
597
        b = a;
598
    }
599
#if 0
600
    for(i=1;i<20;i++) {
601
        float v, r1, r2;
602
        v = 5.0 / i;
603
        r1 = pow_m1_4(s, v);
604
        r2 = pow(v,-0.25);
605
        printf("%f^-0.25=%f e=%f\n", v, r1, r2 - r1);
606
    }
607
#endif
608
}
609

    
610
/* NOTE: We use the same code as Vorbis here */
611
/* XXX: optimize it further with SSE/3Dnow */
612
static void wma_lsp_to_curve(WMADecodeContext *s, 
613
                             float *out, float *val_max_ptr, 
614
                             int n, float *lsp)
615
{
616
    int i, j;
617
    float p, q, w, v, val_max;
618

    
619
    val_max = 0;
620
    for(i=0;i<n;i++) {
621
        p = 0.5f;
622
        q = 0.5f;
623
        w = s->lsp_cos_table[i];
624
        for(j=1;j<NB_LSP_COEFS;j+=2){
625
            q *= w - lsp[j - 1];
626
            p *= w - lsp[j];
627
        }
628
        p *= p * (2.0f - w);
629
        q *= q * (2.0f + w);
630
        v = p + q;
631
        v = pow_m1_4(s, v);
632
        if (v > val_max)
633
            val_max = v;
634
        out[i] = v;
635
    }
636
    *val_max_ptr = val_max;
637
}
638

    
639
/* decode exponents coded with LSP coefficients (same idea as Vorbis) */
640
static void decode_exp_lsp(WMADecodeContext *s, int ch)
641
{
642
    float lsp_coefs[NB_LSP_COEFS];
643
    int val, i;
644

    
645
    for(i = 0; i < NB_LSP_COEFS; i++) {
646
        if (i == 0 || i >= 8)
647
            val = get_bits(&s->gb, 3);
648
        else
649
            val = get_bits(&s->gb, 4);
650
        lsp_coefs[i] = lsp_codebook[i][val];
651
    }
652

    
653
    wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
654
                     s->block_len, lsp_coefs);
655
}
656

    
657
/* decode exponents coded with VLC codes */
658
static int decode_exp_vlc(WMADecodeContext *s, int ch)
659
{
660
    int last_exp, n, code;
661
    const uint16_t *ptr, *band_ptr;
662
    float v, *q, max_scale, *q_end;
663
    
664
    band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
665
    ptr = band_ptr;
666
    q = s->exponents[ch];
667
    q_end = q + s->block_len;
668
    max_scale = 0;
669
    if (s->version == 1) {
670
        last_exp = get_bits(&s->gb, 5) + 10;
671
        /* XXX: use a table */
672
        v = pow(10, last_exp * (1.0 / 16.0));
673
        max_scale = v;
674
        n = *ptr++;
675
        do {
676
            *q++ = v;
677
        } while (--n);
678
    }
679
    last_exp = 36;
680
    while (q < q_end) {
681
        code = get_vlc(&s->gb, &s->exp_vlc);
682
        if (code < 0)
683
            return -1;
684
        /* NOTE: this offset is the same as MPEG4 AAC ! */
685
        last_exp += code - 60;
686
        /* XXX: use a table */
687
        v = pow(10, last_exp * (1.0 / 16.0));
688
        if (v > max_scale)
689
            max_scale = v;
690
        n = *ptr++;
691
        do {
692
            *q++ = v;
693
        } while (--n);
694
    }
695
    s->max_exponent[ch] = max_scale;
696
    return 0;
697
}
698

    
699
/* return 0 if OK. return 1 if last block of frame. return -1 if
700
   unrecorrable error. */
701
static int wma_decode_block(WMADecodeContext *s)
702
{
703
    int n, v, a, ch, code, bsize;
704
    int coef_nb_bits, total_gain, parse_exponents;
705
    float window[BLOCK_MAX_SIZE * 2];
706
// XXX: FIXME!! there's a bug somewhere which makes this mandatory under altivec
707
#ifdef HAVE_ALTIVEC
708
    volatile int nb_coefs[MAX_CHANNELS] __attribute__((aligned(16)));
709
#else
710
    int nb_coefs[MAX_CHANNELS];
711
#endif
712
    float mdct_norm;
713

    
714
#ifdef TRACE
715
    tprintf("***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
716
#endif
717

    
718
    /* compute current block length */
719
    if (s->use_variable_block_len) {
720
        n = av_log2(s->nb_block_sizes - 1) + 1;
721
    
722
        if (s->reset_block_lengths) {
723
            s->reset_block_lengths = 0;
724
            v = get_bits(&s->gb, n);
725
            if (v >= s->nb_block_sizes)
726
                return -1;
727
            s->prev_block_len_bits = s->frame_len_bits - v;
728
            v = get_bits(&s->gb, n);
729
            if (v >= s->nb_block_sizes)
730
                return -1;
731
            s->block_len_bits = s->frame_len_bits - v;
732
        } else {
733
            /* update block lengths */
734
            s->prev_block_len_bits = s->block_len_bits;
735
            s->block_len_bits = s->next_block_len_bits;
736
        }
737
        v = get_bits(&s->gb, n);
738
        if (v >= s->nb_block_sizes)
739
            return -1;
740
        s->next_block_len_bits = s->frame_len_bits - v;
741
    } else {
742
        /* fixed block len */
743
        s->next_block_len_bits = s->frame_len_bits;
744
        s->prev_block_len_bits = s->frame_len_bits;
745
        s->block_len_bits = s->frame_len_bits;
746
    }
747

    
748
    /* now check if the block length is coherent with the frame length */
749
    s->block_len = 1 << s->block_len_bits;
750
    if ((s->block_pos + s->block_len) > s->frame_len)
751
        return -1;
752

    
753
    if (s->nb_channels == 2) {
754
        s->ms_stereo = get_bits(&s->gb, 1);
755
    }
756
    v = 0;
757
    for(ch = 0; ch < s->nb_channels; ch++) {
758
        a = get_bits(&s->gb, 1);
759
        s->channel_coded[ch] = a;
760
        v |= a;
761
    }
762
    /* if no channel coded, no need to go further */
763
    /* XXX: fix potential framing problems */
764
    if (!v)
765
        goto next;
766

    
767
    bsize = s->frame_len_bits - s->block_len_bits;
768

    
769
    /* read total gain and extract corresponding number of bits for
770
       coef escape coding */
771
    total_gain = 1;
772
    for(;;) {
773
        a = get_bits(&s->gb, 7);
774
        total_gain += a;
775
        if (a != 127)
776
            break;
777
    }
778
    
779
    if (total_gain < 15)
780
        coef_nb_bits = 13;
781
    else if (total_gain < 32)
782
        coef_nb_bits = 12;
783
    else if (total_gain < 40)
784
        coef_nb_bits = 11;
785
    else if (total_gain < 45)
786
        coef_nb_bits = 10;
787
    else
788
        coef_nb_bits = 9;
789

    
790
    /* compute number of coefficients */
791
    n = s->coefs_end[bsize] - s->coefs_start;
792
    for(ch = 0; ch < s->nb_channels; ch++)
793
        nb_coefs[ch] = n;
794

    
795
    /* complex coding */
796
    if (s->use_noise_coding) {
797

    
798
        for(ch = 0; ch < s->nb_channels; ch++) {
799
            if (s->channel_coded[ch]) {
800
                int i, n, a;
801
                n = s->exponent_high_sizes[bsize];
802
                for(i=0;i<n;i++) {
803
                    a = get_bits(&s->gb, 1);
804
                    s->high_band_coded[ch][i] = a;
805
                    /* if noise coding, the coefficients are not transmitted */
806
                    if (a)
807
                        nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
808
                }
809
            }
810
        }
811
        for(ch = 0; ch < s->nb_channels; ch++) {
812
            if (s->channel_coded[ch]) {
813
                int i, n, val, code;
814

    
815
                n = s->exponent_high_sizes[bsize];
816
                val = (int)0x80000000;
817
                for(i=0;i<n;i++) {
818
                    if (s->high_band_coded[ch][i]) {
819
                        if (val == (int)0x80000000) {
820
                            val = get_bits(&s->gb, 7) - 19;
821
                        } else {
822
                            code = get_vlc(&s->gb, &s->hgain_vlc);
823
                            if (code < 0)
824
                                return -1;
825
                            val += code - 18;
826
                        }
827
                        s->high_band_values[ch][i] = val;
828
                    }
829
                }
830
            }
831
        }
832
    }
833
           
834
    /* exposant can be interpolated in short blocks. */
835
    parse_exponents = 1;
836
    if (s->block_len_bits != s->frame_len_bits) {
837
        parse_exponents = get_bits(&s->gb, 1);
838
    }
839
    
840
    if (parse_exponents) {
841
        for(ch = 0; ch < s->nb_channels; ch++) {
842
            if (s->channel_coded[ch]) {
843
                if (s->use_exp_vlc) {
844
                    if (decode_exp_vlc(s, ch) < 0)
845
                        return -1;
846
                } else {
847
                    decode_exp_lsp(s, ch);
848
                }
849
            }
850
        }
851
    } else {
852
        for(ch = 0; ch < s->nb_channels; ch++) {
853
            if (s->channel_coded[ch]) {
854
                interpolate_array(s->exponents[ch], 1 << s->prev_block_len_bits, 
855
                                  s->block_len);
856
            }
857
        }
858
    }
859

    
860
    /* parse spectral coefficients : just RLE encoding */
861
    for(ch = 0; ch < s->nb_channels; ch++) {
862
        if (s->channel_coded[ch]) {
863
            VLC *coef_vlc;
864
            int level, run, sign, tindex;
865
            int16_t *ptr, *eptr;
866
            const int16_t *level_table, *run_table;
867

    
868
            /* special VLC tables are used for ms stereo because
869
               there is potentially less energy there */
870
            tindex = (ch == 1 && s->ms_stereo);
871
            coef_vlc = &s->coef_vlc[tindex];
872
            run_table = s->run_table[tindex];
873
            level_table = s->level_table[tindex];
874
            /* XXX: optimize */
875
            ptr = &s->coefs1[ch][0];
876
            eptr = ptr + nb_coefs[ch];
877
            memset(ptr, 0, s->block_len * sizeof(int16_t));
878
            for(;;) {
879
                code = get_vlc(&s->gb, coef_vlc);
880
                if (code < 0)
881
                    return -1;
882
                if (code == 1) {
883
                    /* EOB */
884
                    break;
885
                } else if (code == 0) {
886
                    /* escape */
887
                    level = get_bits(&s->gb, coef_nb_bits);
888
                    /* NOTE: this is rather suboptimal. reading
889
                       block_len_bits would be better */
890
                    run = get_bits(&s->gb, s->frame_len_bits);
891
                } else {
892
                    /* normal code */
893
                    run = run_table[code];
894
                    level = level_table[code];
895
                }
896
                sign = get_bits(&s->gb, 1);
897
                if (!sign)
898
                    level = -level;
899
                ptr += run;
900
                if (ptr >= eptr)
901
                    return -1;
902
                *ptr++ = level;
903
                /* NOTE: EOB can be omitted */
904
                if (ptr >= eptr)
905
                    break;
906
            }
907
        }
908
        if (s->version == 1 && s->nb_channels >= 2) {
909
            align_get_bits(&s->gb);
910
        }
911
    }
912
     
913
    /* normalize */
914
    {
915
        int n4 = s->block_len / 2;
916
        mdct_norm = 1.0 / (float)n4;
917
        if (s->version == 1) {
918
            mdct_norm *= sqrt(n4);
919
        }
920
    }
921

    
922
    /* finally compute the MDCT coefficients */
923
    for(ch = 0; ch < s->nb_channels; ch++) {
924
        if (s->channel_coded[ch]) {
925
            int16_t *coefs1;
926
            float *coefs, *exponents, mult, mult1, noise, *exp_ptr;
927
            int i, j, n, n1, last_high_band;
928
            float exp_power[HIGH_BAND_MAX_SIZE];
929

    
930
            coefs1 = s->coefs1[ch];
931
            exponents = s->exponents[ch];
932
            mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
933
            mult *= mdct_norm;
934
            coefs = s->coefs[ch];
935
            if (s->use_noise_coding) {
936
                mult1 = mult;
937
                /* very low freqs : noise */
938
                for(i = 0;i < s->coefs_start; i++) {
939
                    *coefs++ = s->noise_table[s->noise_index] * (*exponents++) * mult1;
940
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
941
                }
942
                
943
                n1 = s->exponent_high_sizes[bsize];
944

    
945
                /* compute power of high bands */
946
                exp_ptr = exponents + 
947
                    s->high_band_start[bsize] - 
948
                    s->coefs_start;
949
                last_high_band = 0; /* avoid warning */
950
                for(j=0;j<n1;j++) {
951
                    n = s->exponent_high_bands[s->frame_len_bits - 
952
                                              s->block_len_bits][j];
953
                    if (s->high_band_coded[ch][j]) {
954
                        float e2, v;
955
                        e2 = 0;
956
                        for(i = 0;i < n; i++) {
957
                            v = exp_ptr[i];
958
                            e2 += v * v;
959
                        }
960
                        exp_power[j] = e2 / n;
961
                        last_high_band = j;
962
                        tprintf("%d: power=%f (%d)\n", j, exp_power[j], n);
963
                    }
964
                    exp_ptr += n;
965
                }
966

    
967
                /* main freqs and high freqs */
968
                for(j=-1;j<n1;j++) {
969
                    if (j < 0) {
970
                        n = s->high_band_start[bsize] - 
971
                            s->coefs_start;
972
                    } else {
973
                        n = s->exponent_high_bands[s->frame_len_bits - 
974
                                                  s->block_len_bits][j];
975
                    }
976
                    if (j >= 0 && s->high_band_coded[ch][j]) {
977
                        /* use noise with specified power */
978
                        mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
979
                        /* XXX: use a table */
980
                        mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
981
                        mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
982
                        mult1 *= mdct_norm;
983
                        for(i = 0;i < n; i++) {
984
                            noise = s->noise_table[s->noise_index];
985
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
986
                            *coefs++ = (*exponents++) * noise * mult1;
987
                        }
988
                    } else {
989
                        /* coded values + small noise */
990
                        for(i = 0;i < n; i++) {
991
                            noise = s->noise_table[s->noise_index];
992
                            s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
993
                            *coefs++ = ((*coefs1++) + noise) * (*exponents++) * mult;
994
                        }
995
                    }
996
                }
997

    
998
                /* very high freqs : noise */
999
                n = s->block_len - s->coefs_end[bsize];
1000
                mult1 = mult * exponents[-1];
1001
                for(i = 0; i < n; i++) {
1002
                    *coefs++ = s->noise_table[s->noise_index] * mult1;
1003
                    s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
1004
                }
1005
            } else {
1006
                /* XXX: optimize more */
1007
                for(i = 0;i < s->coefs_start; i++)
1008
                    *coefs++ = 0.0;
1009
                n = nb_coefs[ch];
1010
                for(i = 0;i < n; i++) {
1011
                    *coefs++ = coefs1[i] * exponents[i] * mult;
1012
                }
1013
                n = s->block_len - s->coefs_end[bsize];
1014
                for(i = 0;i < n; i++)
1015
                    *coefs++ = 0.0;
1016
            }
1017
        }
1018
    }
1019

    
1020
#ifdef TRACE
1021
    for(ch = 0; ch < s->nb_channels; ch++) {
1022
        if (s->channel_coded[ch]) {
1023
            dump_floats("exponents", 3, s->exponents[ch], s->block_len);
1024
            dump_floats("coefs", 1, s->coefs[ch], s->block_len);
1025
        }
1026
    }
1027
#endif
1028
    
1029
    if (s->ms_stereo && s->channel_coded[1]) {
1030
        float a, b;
1031
        int i;
1032

    
1033
        /* nominal case for ms stereo: we do it before mdct */
1034
        /* no need to optimize this case because it should almost
1035
           never happen */
1036
        if (!s->channel_coded[0]) {
1037
            tprintf("rare ms-stereo case happened\n");
1038
            memset(s->coefs[0], 0, sizeof(float) * s->block_len);
1039
            s->channel_coded[0] = 1;
1040
        }
1041
        
1042
        for(i = 0; i < s->block_len; i++) {
1043
            a = s->coefs[0][i];
1044
            b = s->coefs[1][i];
1045
            s->coefs[0][i] = a + b;
1046
            s->coefs[1][i] = a - b;
1047
        }
1048
    }
1049

    
1050
    /* build the window : we ensure that when the windows overlap
1051
       their squared sum is always 1 (MDCT reconstruction rule) */
1052
    /* XXX: merge with output */
1053
    {
1054
        int i, next_block_len, block_len, prev_block_len, n;
1055
        float *wptr;
1056

    
1057
        block_len = s->block_len;
1058
        prev_block_len = 1 << s->prev_block_len_bits;
1059
        next_block_len = 1 << s->next_block_len_bits;
1060

    
1061
        /* right part */
1062
        wptr = window + block_len;
1063
        if (block_len <= next_block_len) {
1064
            for(i=0;i<block_len;i++)
1065
                *wptr++ = s->windows[bsize][i];
1066
        } else {
1067
            /* overlap */
1068
            n = (block_len / 2) - (next_block_len / 2);
1069
            for(i=0;i<n;i++)
1070
                *wptr++ = 1.0;
1071
            for(i=0;i<next_block_len;i++)
1072
                *wptr++ = s->windows[s->frame_len_bits - s->next_block_len_bits][i];
1073
            for(i=0;i<n;i++)
1074
                *wptr++ = 0.0;
1075
        }
1076

    
1077
        /* left part */
1078
        wptr = window + block_len;
1079
        if (block_len <= prev_block_len) {
1080
            for(i=0;i<block_len;i++)
1081
                *--wptr = s->windows[bsize][i];
1082
        } else {
1083
            /* overlap */
1084
            n = (block_len / 2) - (prev_block_len / 2);
1085
            for(i=0;i<n;i++)
1086
                *--wptr = 1.0;
1087
            for(i=0;i<prev_block_len;i++)
1088
                *--wptr = s->windows[s->frame_len_bits - s->prev_block_len_bits][i];
1089
            for(i=0;i<n;i++)
1090
                *--wptr = 0.0;
1091
        }
1092
    }
1093

    
1094
    
1095
    for(ch = 0; ch < s->nb_channels; ch++) {
1096
        if (s->channel_coded[ch]) {
1097
            FFTSample output[BLOCK_MAX_SIZE * 2] __attribute__((aligned(16)));
1098
            float *ptr;
1099
            int i, n4, index, n;
1100

    
1101
            n = s->block_len;
1102
            n4 = s->block_len / 2;
1103
            ff_imdct_calc(&s->mdct_ctx[bsize], 
1104
                          output, s->coefs[ch], s->mdct_tmp);
1105

    
1106
            /* XXX: optimize all that by build the window and
1107
               multipying/adding at the same time */
1108
            /* multiply by the window */
1109
            for(i=0;i<n * 2;i++) {
1110
                output[i] *= window[i];
1111
            }
1112

    
1113
            /* add in the frame */
1114
            index = (s->frame_len / 2) + s->block_pos - n4;
1115
            ptr = &s->frame_out[ch][index];
1116
            for(i=0;i<n * 2;i++) {
1117
                *ptr += output[i];
1118
                ptr++;
1119
            }
1120

    
1121
            /* specific fast case for ms-stereo : add to second
1122
               channel if it is not coded */
1123
            if (s->ms_stereo && !s->channel_coded[1]) {
1124
                ptr = &s->frame_out[1][index];
1125
                for(i=0;i<n * 2;i++) {
1126
                    *ptr += output[i];
1127
                    ptr++;
1128
                }
1129
            }
1130
        }
1131
    }
1132
 next:
1133
    /* update block number */
1134
    s->block_num++;
1135
    s->block_pos += s->block_len;
1136
    if (s->block_pos >= s->frame_len)
1137
        return 1;
1138
    else
1139
        return 0;
1140
}
1141

    
1142
/* decode a frame of frame_len samples */
1143
static int wma_decode_frame(WMADecodeContext *s, int16_t *samples)
1144
{
1145
    int ret, i, n, a, ch, incr;
1146
    int16_t *ptr;
1147
    float *iptr;
1148

    
1149
#ifdef TRACE
1150
    tprintf("***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
1151
#endif
1152

    
1153
    /* read each block */
1154
    s->block_num = 0;
1155
    s->block_pos = 0;
1156
    for(;;) {
1157
        ret = wma_decode_block(s);
1158
        if (ret < 0) 
1159
            return -1;
1160
        if (ret)
1161
            break;
1162
    }
1163

    
1164
    /* convert frame to integer */
1165
    n = s->frame_len;
1166
    incr = s->nb_channels;
1167
    for(ch = 0; ch < s->nb_channels; ch++) {
1168
        ptr = samples + ch;
1169
        iptr = s->frame_out[ch];
1170

    
1171
        for(i=0;i<n;i++) {
1172
            a = lrintf(*iptr++);
1173
            if (a > 32767)
1174
                a = 32767;
1175
            else if (a < -32768)
1176
                a = -32768;
1177
            *ptr = a;
1178
            ptr += incr;
1179
        }
1180
        /* prepare for next block */
1181
        memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
1182
                s->frame_len * sizeof(float));
1183
        /* XXX: suppress this */
1184
        memset(&s->frame_out[ch][s->frame_len], 0, 
1185
               s->frame_len * sizeof(float));
1186
    }
1187

    
1188
#ifdef TRACE
1189
    dump_shorts("samples", samples, n * s->nb_channels);
1190
#endif
1191
    return 0;
1192
}
1193

    
1194
static int wma_decode_superframe(AVCodecContext *avctx, 
1195
                                 void *data, int *data_size,
1196
                                 uint8_t *buf, int buf_size)
1197
{
1198
    WMADecodeContext *s = avctx->priv_data;
1199
    int nb_frames, bit_offset, i, pos, len;
1200
    uint8_t *q;
1201
    int16_t *samples;
1202
    
1203
    tprintf("***decode_superframe:\n");
1204

    
1205
    if(buf_size==0){
1206
        s->last_superframe_len = 0;
1207
        return 0;
1208
    }
1209
    
1210
    samples = data;
1211

    
1212
    init_get_bits(&s->gb, buf, buf_size*8);
1213
    
1214
    if (s->use_bit_reservoir) {
1215
        /* read super frame header */
1216
        get_bits(&s->gb, 4); /* super frame index */
1217
        nb_frames = get_bits(&s->gb, 4) - 1;
1218

    
1219
        bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
1220

    
1221
        if (s->last_superframe_len > 0) {
1222
            //        printf("skip=%d\n", s->last_bitoffset);
1223
            /* add bit_offset bits to last frame */
1224
            if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) > 
1225
                MAX_CODED_SUPERFRAME_SIZE)
1226
                goto fail;
1227
            q = s->last_superframe + s->last_superframe_len;
1228
            len = bit_offset;
1229
            while (len > 0) {
1230
                *q++ = (get_bits)(&s->gb, 8);
1231
                len -= 8;
1232
            }
1233
            if (len > 0) {
1234
                *q++ = (get_bits)(&s->gb, len) << (8 - len);
1235
            }
1236
            
1237
            /* XXX: bit_offset bits into last frame */
1238
            init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8);
1239
            /* skip unused bits */
1240
            if (s->last_bitoffset > 0)
1241
                skip_bits(&s->gb, s->last_bitoffset);
1242
            /* this frame is stored in the last superframe and in the
1243
               current one */
1244
            if (wma_decode_frame(s, samples) < 0)
1245
                goto fail;
1246
            samples += s->nb_channels * s->frame_len;
1247
        }
1248

    
1249
        /* read each frame starting from bit_offset */
1250
        pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
1251
        init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8);
1252
        len = pos & 7;
1253
        if (len > 0)
1254
            skip_bits(&s->gb, len);
1255
    
1256
        s->reset_block_lengths = 1;
1257
        for(i=0;i<nb_frames;i++) {
1258
            if (wma_decode_frame(s, samples) < 0)
1259
                goto fail;
1260
            samples += s->nb_channels * s->frame_len;
1261
        }
1262

    
1263
        /* we copy the end of the frame in the last frame buffer */
1264
        pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
1265
        s->last_bitoffset = pos & 7;
1266
        pos >>= 3;
1267
        len = buf_size - pos;
1268
        if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
1269
            goto fail;
1270
        }
1271
        s->last_superframe_len = len;
1272
        memcpy(s->last_superframe, buf + pos, len);
1273
    } else {
1274
        /* single frame decode */
1275
        if (wma_decode_frame(s, samples) < 0)
1276
            goto fail;
1277
        samples += s->nb_channels * s->frame_len;
1278
    }
1279
    *data_size = (int8_t *)samples - (int8_t *)data;
1280
    return s->block_align;
1281
 fail:
1282
    /* when error, we reset the bit reservoir */
1283
    s->last_superframe_len = 0;
1284
    return -1;
1285
}
1286

    
1287
static int wma_decode_end(AVCodecContext *avctx)
1288
{
1289
    WMADecodeContext *s = avctx->priv_data;
1290
    int i;
1291

    
1292
    for(i = 0; i < s->nb_block_sizes; i++)
1293
        ff_mdct_end(&s->mdct_ctx[i]);
1294
    for(i = 0; i < s->nb_block_sizes; i++)
1295
        av_free(s->windows[i]);
1296

    
1297
    if (s->use_exp_vlc) {
1298
        free_vlc(&s->exp_vlc);
1299
    }
1300
    if (s->use_noise_coding) {
1301
        free_vlc(&s->hgain_vlc);
1302
    }
1303
    for(i = 0;i < 2; i++) {
1304
        free_vlc(&s->coef_vlc[i]);
1305
        av_free(s->run_table[i]);
1306
        av_free(s->level_table[i]);
1307
    }
1308
    
1309
    return 0;
1310
}
1311

    
1312
AVCodec wmav1_decoder =
1313
{
1314
    "wmav1",
1315
    CODEC_TYPE_AUDIO,
1316
    CODEC_ID_WMAV1,
1317
    sizeof(WMADecodeContext),
1318
    wma_decode_init,
1319
    NULL,
1320
    wma_decode_end,
1321
    wma_decode_superframe,
1322
};
1323

    
1324
AVCodec wmav2_decoder =
1325
{
1326
    "wmav2",
1327
    CODEC_TYPE_AUDIO,
1328
    CODEC_ID_WMAV2,
1329
    sizeof(WMADecodeContext),
1330
    wma_decode_init,
1331
    NULL,
1332
    wma_decode_end,
1333
    wma_decode_superframe,
1334
};