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1
/*
2
 * FLAC (Free Lossless Audio Codec) decoder
3
 * Copyright (c) 2003 Alex Beregszaszi
4
 *
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 * This library is free software; you can redistribute it and/or
6
 * 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
12
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
19

    
20
/**
21
 * @file flac.c
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 * FLAC (Free Lossless Audio Codec) decoder
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 * @author Alex Beregszaszi
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 *
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 * For more information on the FLAC format, visit:
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 *  http://flac.sourceforge.net/
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 *
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 * This decoder can be used in 1 of 2 ways: Either raw FLAC data can be fed
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 * through, starting from the initial 'fLaC' signature; or by passing the
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 * 34-byte streaminfo structure through avctx->extradata[_size] followed
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 * by data starting with the 0xFFF8 marker.
32
 */
33

    
34
#include <limits.h>
35

    
36
#include "avcodec.h"
37
#include "bitstream.h"
38
#include "golomb.h"
39
#include "crc.h"
40

    
41
#undef NDEBUG
42
#include <assert.h>
43

    
44
#define MAX_CHANNELS 8
45
#define MAX_BLOCKSIZE 65535
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#define FLAC_STREAMINFO_SIZE 34
47

    
48
enum decorrelation_type {
49
    INDEPENDENT,
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    LEFT_SIDE,
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    RIGHT_SIDE,
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    MID_SIDE,
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};
54

    
55
typedef struct FLACContext {
56
    AVCodecContext *avctx;
57
    GetBitContext gb;
58

    
59
    int min_blocksize, max_blocksize;
60
    int min_framesize, max_framesize;
61
    int samplerate, channels;
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    int blocksize/*, last_blocksize*/;
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    int bps, curr_bps;
64
    enum decorrelation_type decorrelation;
65

    
66
    int32_t *decoded[MAX_CHANNELS];
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    uint8_t *bitstream;
68
    int bitstream_size;
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    int bitstream_index;
70
    unsigned int allocated_bitstream_size;
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} FLACContext;
72

    
73
#define METADATA_TYPE_STREAMINFO 0
74

    
75
static int sample_rate_table[] =
76
{ 0, 0, 0, 0,
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  8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
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  0, 0, 0, 0 };
79

    
80
static int sample_size_table[] =
81
{ 0, 8, 12, 0, 16, 20, 24, 0 };
82

    
83
static int blocksize_table[] = {
84
     0,    192, 576<<0, 576<<1, 576<<2, 576<<3,      0,      0,
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256<<0, 256<<1, 256<<2, 256<<3, 256<<4, 256<<5, 256<<6, 256<<7
86
};
87

    
88
static int64_t get_utf8(GetBitContext *gb)
89
{
90
    uint64_t val;
91
    int ones=0, bytes;
92

    
93
    while(get_bits1(gb))
94
        ones++;
95

    
96
    if     (ones==0) bytes=0;
97
    else if(ones==1) return -1;
98
    else             bytes= ones - 1;
99

    
100
    val= get_bits(gb, 7-ones);
101
    while(bytes--){
102
        const int tmp = get_bits(gb, 8);
103

    
104
        if((tmp>>6) != 2)
105
            return -1;
106
        val<<=6;
107
        val|= tmp&0x3F;
108
    }
109
    return val;
110
}
111

    
112
#if 0
113
static int skip_utf8(GetBitContext *gb)
114
{
115
    int ones=0, bytes;
116

117
    while(get_bits1(gb))
118
        ones++;
119

120
    if     (ones==0) bytes=0;
121
    else if(ones==1) return -1;
122
    else             bytes= ones - 1;
123

124
    skip_bits(gb, 7-ones);
125
    while(bytes--){
126
        const int tmp = get_bits(gb, 8);
127

128
        if((tmp>>6) != 2)
129
            return -1;
130
    }
131
    return 0;
132
}
133
#endif
134

    
135
static void metadata_streaminfo(FLACContext *s);
136
static void dump_headers(FLACContext *s);
137

    
138
static int flac_decode_init(AVCodecContext * avctx)
139
{
140
    FLACContext *s = avctx->priv_data;
141
    s->avctx = avctx;
142

    
143
    /* initialize based on the demuxer-supplied streamdata header */
144
    if (avctx->extradata_size == FLAC_STREAMINFO_SIZE) {
145
        init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size*8);
146
        metadata_streaminfo(s);
147
        dump_headers(s);
148
    }
149

    
150
    return 0;
151
}
152

    
153
static void dump_headers(FLACContext *s)
154
{
155
    av_log(s->avctx, AV_LOG_DEBUG, "  Blocksize: %d .. %d (%d)\n", s->min_blocksize, s->max_blocksize, s->blocksize);
156
    av_log(s->avctx, AV_LOG_DEBUG, "  Framesize: %d .. %d\n", s->min_framesize, s->max_framesize);
157
    av_log(s->avctx, AV_LOG_DEBUG, "  Samplerate: %d\n", s->samplerate);
158
    av_log(s->avctx, AV_LOG_DEBUG, "  Channels: %d\n", s->channels);
159
    av_log(s->avctx, AV_LOG_DEBUG, "  Bits: %d\n", s->bps);
160
}
161

    
162
static void allocate_buffers(FLACContext *s){
163
    int i;
164

    
165
    assert(s->max_blocksize);
166

    
167
    if(s->max_framesize == 0 && s->max_blocksize){
168
        s->max_framesize= (s->channels * s->bps * s->max_blocksize + 7)/ 8; //FIXME header overhead
169
    }
170

    
171
    for (i = 0; i < s->channels; i++)
172
    {
173
        s->decoded[i] = av_realloc(s->decoded[i], sizeof(int32_t)*s->max_blocksize);
174
    }
175

    
176
    s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
177
}
178

    
179
static void metadata_streaminfo(FLACContext *s)
180
{
181
    /* mandatory streaminfo */
182
    s->min_blocksize = get_bits(&s->gb, 16);
183
    s->max_blocksize = get_bits(&s->gb, 16);
184

    
185
    s->min_framesize = get_bits_long(&s->gb, 24);
186
    s->max_framesize = get_bits_long(&s->gb, 24);
187

    
188
    s->samplerate = get_bits_long(&s->gb, 20);
189
    s->channels = get_bits(&s->gb, 3) + 1;
190
    s->bps = get_bits(&s->gb, 5) + 1;
191

    
192
    s->avctx->channels = s->channels;
193
    s->avctx->sample_rate = s->samplerate;
194

    
195
    skip_bits(&s->gb, 36); /* total num of samples */
196

    
197
    skip_bits(&s->gb, 64); /* md5 sum */
198
    skip_bits(&s->gb, 64); /* md5 sum */
199

    
200
    allocate_buffers(s);
201
}
202

    
203
static int decode_residuals(FLACContext *s, int channel, int pred_order)
204
{
205
    int i, tmp, partition, method_type, rice_order;
206
    int sample = 0, samples;
207

    
208
    method_type = get_bits(&s->gb, 2);
209
    if (method_type != 0){
210
        av_log(s->avctx, AV_LOG_DEBUG, "illegal residual coding method %d\n", method_type);
211
        return -1;
212
    }
213

    
214
    rice_order = get_bits(&s->gb, 4);
215

    
216
    samples= s->blocksize >> rice_order;
217

    
218
    sample=
219
    i= pred_order;
220
    for (partition = 0; partition < (1 << rice_order); partition++)
221
    {
222
        tmp = get_bits(&s->gb, 4);
223
        if (tmp == 15)
224
        {
225
            av_log(s->avctx, AV_LOG_DEBUG, "fixed len partition\n");
226
            tmp = get_bits(&s->gb, 5);
227
            for (; i < samples; i++, sample++)
228
                s->decoded[channel][sample] = get_sbits(&s->gb, tmp);
229
        }
230
        else
231
        {
232
//            av_log(s->avctx, AV_LOG_DEBUG, "rice coded partition k=%d\n", tmp);
233
            for (; i < samples; i++, sample++){
234
                s->decoded[channel][sample] = get_sr_golomb_flac(&s->gb, tmp, INT_MAX, 0);
235
            }
236
        }
237
        i= 0;
238
    }
239

    
240
//    av_log(s->avctx, AV_LOG_DEBUG, "partitions: %d, samples: %d\n", 1 << rice_order, sample);
241

    
242
    return 0;
243
}
244

    
245
static int decode_subframe_fixed(FLACContext *s, int channel, int pred_order)
246
{
247
    int i;
248

    
249
//    av_log(s->avctx, AV_LOG_DEBUG, "  SUBFRAME FIXED\n");
250

    
251
    /* warm up samples */
252
//    av_log(s->avctx, AV_LOG_DEBUG, "   warm up samples: %d\n", pred_order);
253

    
254
    for (i = 0; i < pred_order; i++)
255
    {
256
        s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
257
//        av_log(s->avctx, AV_LOG_DEBUG, "    %d: %d\n", i, s->decoded[channel][i]);
258
    }
259

    
260
    if (decode_residuals(s, channel, pred_order) < 0)
261
        return -1;
262

    
263
    switch(pred_order)
264
    {
265
        case 0:
266
            break;
267
        case 1:
268
            for (i = pred_order; i < s->blocksize; i++)
269
                s->decoded[channel][i] +=   s->decoded[channel][i-1];
270
            break;
271
        case 2:
272
            for (i = pred_order; i < s->blocksize; i++)
273
                s->decoded[channel][i] += 2*s->decoded[channel][i-1]
274
                                          - s->decoded[channel][i-2];
275
            break;
276
        case 3:
277
            for (i = pred_order; i < s->blocksize; i++)
278
                s->decoded[channel][i] += 3*s->decoded[channel][i-1]
279
                                        - 3*s->decoded[channel][i-2]
280
                                        +   s->decoded[channel][i-3];
281
            break;
282
        case 4:
283
            for (i = pred_order; i < s->blocksize; i++)
284
                s->decoded[channel][i] += 4*s->decoded[channel][i-1]
285
                                        - 6*s->decoded[channel][i-2]
286
                                        + 4*s->decoded[channel][i-3]
287
                                        -   s->decoded[channel][i-4];
288
            break;
289
        default:
290
            av_log(s->avctx, AV_LOG_ERROR, "illegal pred order %d\n", pred_order);
291
            return -1;
292
    }
293

    
294
    return 0;
295
}
296

    
297
static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
298
{
299
    int i, j;
300
    int coeff_prec, qlevel;
301
    int coeffs[pred_order];
302

    
303
//    av_log(s->avctx, AV_LOG_DEBUG, "  SUBFRAME LPC\n");
304

    
305
    /* warm up samples */
306
//    av_log(s->avctx, AV_LOG_DEBUG, "   warm up samples: %d\n", pred_order);
307

    
308
    for (i = 0; i < pred_order; i++)
309
    {
310
        s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
311
//        av_log(s->avctx, AV_LOG_DEBUG, "    %d: %d\n", i, s->decoded[channel][i]);
312
    }
313

    
314
    coeff_prec = get_bits(&s->gb, 4) + 1;
315
    if (coeff_prec == 16)
316
    {
317
        av_log(s->avctx, AV_LOG_DEBUG, "invalid coeff precision\n");
318
        return -1;
319
    }
320
//    av_log(s->avctx, AV_LOG_DEBUG, "   qlp coeff prec: %d\n", coeff_prec);
321
    qlevel = get_sbits(&s->gb, 5);
322
//    av_log(s->avctx, AV_LOG_DEBUG, "   quant level: %d\n", qlevel);
323
    if(qlevel < 0){
324
        av_log(s->avctx, AV_LOG_DEBUG, "qlevel %d not supported, maybe buggy stream\n", qlevel);
325
        return -1;
326
    }
327

    
328
    for (i = 0; i < pred_order; i++)
329
    {
330
        coeffs[i] = get_sbits(&s->gb, coeff_prec);
331
//        av_log(s->avctx, AV_LOG_DEBUG, "    %d: %d\n", i, coeffs[i]);
332
    }
333

    
334
    if (decode_residuals(s, channel, pred_order) < 0)
335
        return -1;
336

    
337
    if (s->bps > 16) {
338
        int64_t sum;
339
        for (i = pred_order; i < s->blocksize; i++)
340
        {
341
            sum = 0;
342
            for (j = 0; j < pred_order; j++)
343
                sum += (int64_t)coeffs[j] * s->decoded[channel][i-j-1];
344
            s->decoded[channel][i] += sum >> qlevel;
345
        }
346
    } else {
347
        int sum;
348
        for (i = pred_order; i < s->blocksize; i++)
349
        {
350
            sum = 0;
351
            for (j = 0; j < pred_order; j++)
352
                sum += coeffs[j] * s->decoded[channel][i-j-1];
353
            s->decoded[channel][i] += sum >> qlevel;
354
        }
355
    }
356

    
357
    return 0;
358
}
359

    
360
static inline int decode_subframe(FLACContext *s, int channel)
361
{
362
    int type, wasted = 0;
363
    int i, tmp;
364

    
365
    s->curr_bps = s->bps;
366
    if(channel == 0){
367
        if(s->decorrelation == RIGHT_SIDE)
368
            s->curr_bps++;
369
    }else{
370
        if(s->decorrelation == LEFT_SIDE || s->decorrelation == MID_SIDE)
371
            s->curr_bps++;
372
    }
373

    
374
    if (get_bits1(&s->gb))
375
    {
376
        av_log(s->avctx, AV_LOG_ERROR, "invalid subframe padding\n");
377
        return -1;
378
    }
379
    type = get_bits(&s->gb, 6);
380
//    wasted = get_bits1(&s->gb);
381

    
382
//    if (wasted)
383
//    {
384
//        while (!get_bits1(&s->gb))
385
//            wasted++;
386
//        if (wasted)
387
//            wasted++;
388
//        s->curr_bps -= wasted;
389
//    }
390
#if 0
391
    wasted= 16 - av_log2(show_bits(&s->gb, 17));
392
    skip_bits(&s->gb, wasted+1);
393
    s->curr_bps -= wasted;
394
#else
395
    if (get_bits1(&s->gb))
396
    {
397
        wasted = 1;
398
        while (!get_bits1(&s->gb))
399
            wasted++;
400
        s->curr_bps -= wasted;
401
        av_log(s->avctx, AV_LOG_DEBUG, "%d wasted bits\n", wasted);
402
    }
403
#endif
404
//FIXME use av_log2 for types
405
    if (type == 0)
406
    {
407
        av_log(s->avctx, AV_LOG_DEBUG, "coding type: constant\n");
408
        tmp = get_sbits(&s->gb, s->curr_bps);
409
        for (i = 0; i < s->blocksize; i++)
410
            s->decoded[channel][i] = tmp;
411
    }
412
    else if (type == 1)
413
    {
414
        av_log(s->avctx, AV_LOG_DEBUG, "coding type: verbatim\n");
415
        for (i = 0; i < s->blocksize; i++)
416
            s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
417
    }
418
    else if ((type >= 8) && (type <= 12))
419
    {
420
//        av_log(s->avctx, AV_LOG_DEBUG, "coding type: fixed\n");
421
        if (decode_subframe_fixed(s, channel, type & ~0x8) < 0)
422
            return -1;
423
    }
424
    else if (type >= 32)
425
    {
426
//        av_log(s->avctx, AV_LOG_DEBUG, "coding type: lpc\n");
427
        if (decode_subframe_lpc(s, channel, (type & ~0x20)+1) < 0)
428
            return -1;
429
    }
430
    else
431
    {
432
        av_log(s->avctx, AV_LOG_ERROR, "invalid coding type\n");
433
        return -1;
434
    }
435

    
436
    if (wasted)
437
    {
438
        int i;
439
        for (i = 0; i < s->blocksize; i++)
440
            s->decoded[channel][i] <<= wasted;
441
    }
442

    
443
    return 0;
444
}
445

    
446
static int decode_frame(FLACContext *s)
447
{
448
    int blocksize_code, sample_rate_code, sample_size_code, assignment, i, crc8;
449
    int decorrelation, bps, blocksize, samplerate;
450

    
451
    blocksize_code = get_bits(&s->gb, 4);
452

    
453
    sample_rate_code = get_bits(&s->gb, 4);
454

    
455
    assignment = get_bits(&s->gb, 4); /* channel assignment */
456
    if (assignment < 8 && s->channels == assignment+1)
457
        decorrelation = INDEPENDENT;
458
    else if (assignment >=8 && assignment < 11 && s->channels == 2)
459
        decorrelation = LEFT_SIDE + assignment - 8;
460
    else
461
    {
462
        av_log(s->avctx, AV_LOG_ERROR, "unsupported channel assignment %d (channels=%d)\n", assignment, s->channels);
463
        return -1;
464
    }
465

    
466
    sample_size_code = get_bits(&s->gb, 3);
467
    if(sample_size_code == 0)
468
        bps= s->bps;
469
    else if((sample_size_code != 3) && (sample_size_code != 7))
470
        bps = sample_size_table[sample_size_code];
471
    else
472
    {
473
        av_log(s->avctx, AV_LOG_ERROR, "invalid sample size code (%d)\n", sample_size_code);
474
        return -1;
475
    }
476

    
477
    if (get_bits1(&s->gb))
478
    {
479
        av_log(s->avctx, AV_LOG_ERROR, "broken stream, invalid padding\n");
480
        return -1;
481
    }
482

    
483
    if(get_utf8(&s->gb) < 0){
484
        av_log(s->avctx, AV_LOG_ERROR, "utf8 fscked\n");
485
        return -1;
486
    }
487
#if 0
488
    if (/*((blocksize_code == 6) || (blocksize_code == 7)) &&*/
489
        (s->min_blocksize != s->max_blocksize)){
490
    }else{
491
    }
492
#endif
493

    
494
    if (blocksize_code == 0)
495
        blocksize = s->min_blocksize;
496
    else if (blocksize_code == 6)
497
        blocksize = get_bits(&s->gb, 8)+1;
498
    else if (blocksize_code == 7)
499
        blocksize = get_bits(&s->gb, 16)+1;
500
    else
501
        blocksize = blocksize_table[blocksize_code];
502

    
503
    if(blocksize > s->max_blocksize){
504
        av_log(s->avctx, AV_LOG_ERROR, "blocksize %d > %d\n", blocksize, s->max_blocksize);
505
        return -1;
506
    }
507

    
508
    if (sample_rate_code == 0){
509
        samplerate= s->samplerate;
510
    }else if ((sample_rate_code > 3) && (sample_rate_code < 12))
511
        samplerate = sample_rate_table[sample_rate_code];
512
    else if (sample_rate_code == 12)
513
        samplerate = get_bits(&s->gb, 8) * 1000;
514
    else if (sample_rate_code == 13)
515
        samplerate = get_bits(&s->gb, 16);
516
    else if (sample_rate_code == 14)
517
        samplerate = get_bits(&s->gb, 16) * 10;
518
    else{
519
        av_log(s->avctx, AV_LOG_ERROR, "illegal sample rate code %d\n", sample_rate_code);
520
        return -1;
521
    }
522

    
523
    skip_bits(&s->gb, 8);
524
    crc8= av_crc(av_crc07, 0, s->gb.buffer, get_bits_count(&s->gb)/8);
525
    if(crc8){
526
        av_log(s->avctx, AV_LOG_ERROR, "header crc mismatch crc=%2X\n", crc8);
527
        return -1;
528
    }
529

    
530
    s->blocksize    = blocksize;
531
    s->samplerate   = samplerate;
532
    s->bps          = bps;
533
    s->decorrelation= decorrelation;
534

    
535
//    dump_headers(s);
536

    
537
    /* subframes */
538
    for (i = 0; i < s->channels; i++)
539
    {
540
//        av_log(s->avctx, AV_LOG_DEBUG, "decoded: %x residual: %x\n", s->decoded[i], s->residual[i]);
541
        if (decode_subframe(s, i) < 0)
542
            return -1;
543
    }
544

    
545
    align_get_bits(&s->gb);
546

    
547
    /* frame footer */
548
    skip_bits(&s->gb, 16); /* data crc */
549

    
550
    return 0;
551
}
552

    
553
static inline int16_t shift_to_16_bits(int32_t data, int bps)
554
{
555
    if (bps == 24) {
556
        return (data >> 8);
557
    } else if (bps == 20) {
558
        return (data >> 4);
559
    } else {
560
        return data;
561
    }
562
}
563

    
564
static int flac_decode_frame(AVCodecContext *avctx,
565
                            void *data, int *data_size,
566
                            uint8_t *buf, int buf_size)
567
{
568
    FLACContext *s = avctx->priv_data;
569
    int metadata_last, metadata_type, metadata_size;
570
    int tmp = 0, i, j = 0, input_buf_size = 0;
571
    int16_t *samples = data;
572

    
573
    if(s->max_framesize == 0){
574
        s->max_framesize= 65536; // should hopefully be enough for the first header
575
        s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
576
    }
577

    
578
    if(1 && s->max_framesize){//FIXME truncated
579
            buf_size= FFMAX(FFMIN(buf_size, s->max_framesize - s->bitstream_size), 0);
580
            input_buf_size= buf_size;
581

    
582
            if(s->bitstream_index + s->bitstream_size + buf_size > s->allocated_bitstream_size){
583
//                printf("memmove\n");
584
                memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
585
                s->bitstream_index=0;
586
            }
587
            memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
588
            buf= &s->bitstream[s->bitstream_index];
589
            buf_size += s->bitstream_size;
590
            s->bitstream_size= buf_size;
591

    
592
            if(buf_size < s->max_framesize){
593
//                printf("wanna more data ...\n");
594
                return input_buf_size;
595
            }
596
    }
597

    
598
    init_get_bits(&s->gb, buf, buf_size*8);
599

    
600
    /* fLaC signature (be) */
601
    if (show_bits_long(&s->gb, 32) == bswap_32(ff_get_fourcc("fLaC")))
602
    {
603
        skip_bits(&s->gb, 32);
604

    
605
        av_log(s->avctx, AV_LOG_DEBUG, "STREAM HEADER\n");
606
        do {
607
            metadata_last = get_bits(&s->gb, 1);
608
            metadata_type = get_bits(&s->gb, 7);
609
            metadata_size = get_bits_long(&s->gb, 24);
610

    
611
            av_log(s->avctx, AV_LOG_DEBUG, " metadata block: flag = %d, type = %d, size = %d\n",
612
                metadata_last, metadata_type,
613
                metadata_size);
614
            if(metadata_size){
615
                switch(metadata_type)
616
                {
617
                case METADATA_TYPE_STREAMINFO:{
618
                    metadata_streaminfo(s);
619

    
620
                    /* Buffer might have been reallocated, reinit bitreader */
621
                    if(buf != &s->bitstream[s->bitstream_index])
622
                    {
623
                        int bits_count = get_bits_count(&s->gb);
624
                        buf= &s->bitstream[s->bitstream_index];
625
                        init_get_bits(&s->gb, buf, buf_size*8);
626
                        skip_bits(&s->gb, bits_count);
627
                    }
628

    
629
                    dump_headers(s);
630
                    break;}
631
                default:
632
                    for(i=0; i<metadata_size; i++)
633
                        skip_bits(&s->gb, 8);
634
                }
635
            }
636
        } while(!metadata_last);
637
    }
638
    else
639
    {
640

    
641
        tmp = show_bits(&s->gb, 16);
642
        if(tmp != 0xFFF8){
643
            av_log(s->avctx, AV_LOG_ERROR, "FRAME HEADER not here\n");
644
            while(get_bits_count(&s->gb)/8+2 < buf_size && show_bits(&s->gb, 16) != 0xFFF8)
645
                skip_bits(&s->gb, 8);
646
            goto end; // we may not have enough bits left to decode a frame, so try next time
647
        }
648
        skip_bits(&s->gb, 16);
649
        if (decode_frame(s) < 0){
650
            av_log(s->avctx, AV_LOG_ERROR, "decode_frame() failed\n");
651
            s->bitstream_size=0;
652
            s->bitstream_index=0;
653
            return -1;
654
        }
655
    }
656

    
657

    
658
#if 0
659
    /* fix the channel order here */
660
    if (s->order == MID_SIDE)
661
    {
662
        short *left = samples;
663
        short *right = samples + s->blocksize;
664
        for (i = 0; i < s->blocksize; i += 2)
665
        {
666
            uint32_t x = s->decoded[0][i];
667
            uint32_t y = s->decoded[0][i+1];
668

669
            right[i] = x - (y / 2);
670
            left[i] = right[i] + y;
671
        }
672
        *data_size = 2 * s->blocksize;
673
    }
674
    else
675
    {
676
    for (i = 0; i < s->channels; i++)
677
    {
678
        switch(s->order)
679
        {
680
            case INDEPENDENT:
681
                for (j = 0; j < s->blocksize; j++)
682
                    samples[(s->blocksize*i)+j] = s->decoded[i][j];
683
                break;
684
            case LEFT_SIDE:
685
            case RIGHT_SIDE:
686
                if (i == 0)
687
                    for (j = 0; j < s->blocksize; j++)
688
                        samples[(s->blocksize*i)+j] = s->decoded[0][j];
689
                else
690
                    for (j = 0; j < s->blocksize; j++)
691
                        samples[(s->blocksize*i)+j] = s->decoded[0][j] - s->decoded[i][j];
692
                break;
693
//            case MID_SIDE:
694
//                av_log(s->avctx, AV_LOG_DEBUG, "mid-side unsupported\n");
695
        }
696
        *data_size += s->blocksize;
697
    }
698
    }
699
#else
700
    switch(s->decorrelation)
701
    {
702
        case INDEPENDENT:
703
            for (j = 0; j < s->blocksize; j++)
704
            {
705
                for (i = 0; i < s->channels; i++)
706
                    *(samples++) = shift_to_16_bits(s->decoded[i][j], s->bps);
707
            }
708
            break;
709
        case LEFT_SIDE:
710
            assert(s->channels == 2);
711
            for (i = 0; i < s->blocksize; i++)
712
            {
713
                *(samples++) = shift_to_16_bits(s->decoded[0][i], s->bps);
714
                *(samples++) = shift_to_16_bits(s->decoded[0][i]
715
                                              - s->decoded[1][i], s->bps);
716
            }
717
            break;
718
        case RIGHT_SIDE:
719
            assert(s->channels == 2);
720
            for (i = 0; i < s->blocksize; i++)
721
            {
722
                *(samples++) = shift_to_16_bits(s->decoded[0][i]
723
                                              + s->decoded[1][i], s->bps);
724
                *(samples++) = shift_to_16_bits(s->decoded[1][i], s->bps);
725
            }
726
            break;
727
        case MID_SIDE:
728
            assert(s->channels == 2);
729
            for (i = 0; i < s->blocksize; i++)
730
            {
731
                int mid, side;
732
                mid = s->decoded[0][i];
733
                side = s->decoded[1][i];
734

    
735
#if 1 //needs to be checked but IMHO it should be binary identical
736
                mid -= side>>1;
737
                *(samples++) = shift_to_16_bits(mid + side, s->bps);
738
                *(samples++) = shift_to_16_bits(mid, s->bps);
739
#else
740

    
741
                mid <<= 1;
742
                if (side & 1)
743
                    mid++;
744
                *(samples++) = (mid + side) >> 1;
745
                *(samples++) = (mid - side) >> 1;
746
#endif
747
            }
748
            break;
749
    }
750
#endif
751

    
752
    *data_size = (int8_t *)samples - (int8_t *)data;
753
//    av_log(s->avctx, AV_LOG_DEBUG, "data size: %d\n", *data_size);
754

    
755
//    s->last_blocksize = s->blocksize;
756
end:
757
    i= (get_bits_count(&s->gb)+7)/8;;
758
    if(i > buf_size){
759
        av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);
760
        s->bitstream_size=0;
761
        s->bitstream_index=0;
762
        return -1;
763
    }
764

    
765
    if(s->bitstream_size){
766
        s->bitstream_index += i;
767
        s->bitstream_size  -= i;
768
        return input_buf_size;
769
    }else
770
        return i;
771
}
772

    
773
static int flac_decode_close(AVCodecContext *avctx)
774
{
775
    FLACContext *s = avctx->priv_data;
776
    int i;
777

    
778
    for (i = 0; i < s->channels; i++)
779
    {
780
        av_freep(&s->decoded[i]);
781
    }
782
    av_freep(&s->bitstream);
783

    
784
    return 0;
785
}
786

    
787
static void flac_flush(AVCodecContext *avctx){
788
    FLACContext *s = avctx->priv_data;
789

    
790
    s->bitstream_size=
791
    s->bitstream_index= 0;
792
}
793

    
794
AVCodec flac_decoder = {
795
    "flac",
796
    CODEC_TYPE_AUDIO,
797
    CODEC_ID_FLAC,
798
    sizeof(FLACContext),
799
    flac_decode_init,
800
    NULL,
801
    flac_decode_close,
802
    flac_decode_frame,
803
    .flush= flac_flush,
804
};