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1 730581f3 Kostya Shishkov
/*
2
 * WavPack lossless audio decoder
3
 * Copyright (c) 2006 Konstantin Shishkov
4
 *
5 b78e7197 Diego Biurrun
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8 730581f3 Kostya Shishkov
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10 b78e7197 Diego Biurrun
 * version 2.1 of the License, or (at your option) any later version.
11 730581f3 Kostya Shishkov
 *
12 b78e7197 Diego Biurrun
 * FFmpeg is distributed in the hope that it will be useful,
13 730581f3 Kostya Shishkov
 * 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 b78e7197 Diego Biurrun
 * License along with FFmpeg; if not, write to the Free Software
19 730581f3 Kostya Shishkov
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21
#define ALT_BITSTREAM_READER_LE
22
#include "avcodec.h"
23
#include "bitstream.h"
24
25
/**
26
 * @file wavpack.c
27
 * WavPack lossless audio decoder
28
 */
29
30
#define WV_JOINT 0x0010
31
32
enum WP_ID_Flags{
33
    WP_IDF_MASK   = 0x1F,
34
    WP_IDF_IGNORE = 0x20,
35
    WP_IDF_ODD    = 0x40,
36
    WP_IDF_LONG   = 0x80
37
};
38
39
enum WP_ID{
40
    WP_ID_DUMMY = 0,
41
    WP_ID_ENCINFO,
42
    WP_ID_DECTERMS,
43
    WP_ID_DECWEIGHTS,
44
    WP_ID_DECSAMPLES,
45
    WP_ID_ENTROPY,
46
    WP_ID_HYBRID,
47
    WP_ID_SHAPING,
48
    WP_ID_FLOATINFO,
49
    WP_ID_INT32INFO,
50
    WP_ID_DATA,
51
    WP_ID_CORR,
52
    WP_ID_FLT,
53
    WP_ID_CHANINFO
54
};
55
56
#define MAX_TERMS 16
57
58
typedef struct Decorr {
59
    int delta;
60
    int value;
61
    int weightA;
62
    int weightB;
63
    int samplesA[8];
64
    int samplesB[8];
65
} Decorr;
66
67
typedef struct WavpackContext {
68
    AVCodecContext *avctx;
69
    int stereo;
70
    int joint;
71
    uint32_t CRC;
72
    GetBitContext gb;
73
    int data_size; // in bits
74
    int samples;
75
    int median[6];
76
    int terms;
77
    Decorr decorr[MAX_TERMS];
78
    int zero, one, zeroes;
79
} WavpackContext;
80
81
// exponent table copied from WavPack source
82
static const uint8_t wp_exp2_table [256] = {
83
    0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x06, 0x07, 0x08, 0x08, 0x09, 0x0a, 0x0b,
84
    0x0b, 0x0c, 0x0d, 0x0e, 0x0e, 0x0f, 0x10, 0x10, 0x11, 0x12, 0x13, 0x13, 0x14, 0x15, 0x16, 0x16,
85
    0x17, 0x18, 0x19, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1d, 0x1e, 0x1f, 0x20, 0x20, 0x21, 0x22, 0x23,
86
    0x24, 0x24, 0x25, 0x26, 0x27, 0x28, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2c, 0x2d, 0x2e, 0x2f, 0x30,
87
    0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3a, 0x3b, 0x3c, 0x3d,
88
    0x3e, 0x3f, 0x40, 0x41, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x48, 0x49, 0x4a, 0x4b,
89
    0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a,
90
    0x5b, 0x5c, 0x5d, 0x5e, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
91
    0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
92
    0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x87, 0x88, 0x89, 0x8a,
93
    0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b,
94
    0x9c, 0x9d, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad,
95
    0xaf, 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0,
96
    0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc8, 0xc9, 0xca, 0xcb, 0xcd, 0xce, 0xcf, 0xd0, 0xd2, 0xd3, 0xd4,
97
    0xd6, 0xd7, 0xd8, 0xd9, 0xdb, 0xdc, 0xdd, 0xde, 0xe0, 0xe1, 0xe2, 0xe4, 0xe5, 0xe6, 0xe8, 0xe9,
98
    0xea, 0xec, 0xed, 0xee, 0xf0, 0xf1, 0xf2, 0xf4, 0xf5, 0xf6, 0xf8, 0xf9, 0xfa, 0xfc, 0xfd, 0xff
99
};
100
101 849f1035 Måns Rullgård
static av_always_inline int wp_exp2(int16_t val)
102 730581f3 Kostya Shishkov
{
103
    int res, neg = 0;
104
105
    if(val < 0){
106
        val = -val;
107
        neg = 1;
108
    }
109
110
    res = wp_exp2_table[val & 0xFF] | 0x100;
111
    val >>= 8;
112
    res = (val > 9) ? (res << (val - 9)) : (res >> (9 - val));
113
    return neg ? -res : res;
114
}
115
116
static inline int get_unary(GetBitContext *gb){
117
    int r=0;
118
    while(get_bits1(gb) && r<33)r++;
119
    return r;
120
}
121
122
// macros for manipulating median values
123
#define GET_MED(n) ((median[n] >> 4) + 1)
124
#define DEC_MED(n) median[n] -= ((median[n] + (128>>n) - 2) / (128>>n)) * 2
125
#define INC_MED(n) median[n] += ((median[n] + (128>>n)) / (128>>n)) * 5
126
127
// macros for applying weight
128
#define UPDATE_WEIGHT_CLIP(weight, delta, samples, in) \
129
        if(samples && in){ \
130
            if((samples ^ in) < 0){ \
131
                weight -= delta; \
132
                if(weight < -1024) weight = -1024; \
133
            }else{ \
134
                weight += delta; \
135
                if(weight > 1024) weight = 1024; \
136
            } \
137
        }
138
139
140 849f1035 Måns Rullgård
static av_always_inline int get_tail(GetBitContext *gb, int k)
141 730581f3 Kostya Shishkov
{
142
    int p, e, res;
143
144
    if(k<1 || k>65535)return 0;
145
    p = av_log2_16bit(k);
146
    e = (1 << (p + 1)) - k - 1;
147 8db0c25d Kostya Shishkov
    res = p ? get_bits(gb, p) : 0;
148 730581f3 Kostya Shishkov
    if(res >= e){
149
        res = (res<<1) - e + get_bits1(gb);
150
    }
151
    return res;
152
}
153
154
static int wv_get_value(WavpackContext *ctx, GetBitContext *gb, int *median, int *last)
155
{
156
    int t, t2;
157
    int sign, base, add, ret;
158
159
    *last = 0;
160
161
    if((ctx->median[0] < 2U) && (ctx->median[3] < 2U) && !ctx->zero && !ctx->one){
162
        if(ctx->zeroes){
163
            ctx->zeroes--;
164
            if(ctx->zeroes)
165
                return 0;
166
        }else{
167
            t = get_unary(gb);
168
            if(t >= 2) t = get_bits(gb, t - 1) | (1 << (t-1));
169
            ctx->zeroes = t;
170
            if(ctx->zeroes){
171
                memset(ctx->median, 0, sizeof(ctx->median));
172
                return 0;
173
            }
174
        }
175
    }
176
177
    if(get_bits_count(gb) >= ctx->data_size){
178
        *last = 1;
179
        return 0;
180
    }
181
182
    if(ctx->zero){
183
        t = 0;
184
        ctx->zero = 0;
185
    }else{
186
        t = get_unary(gb);
187
        if(get_bits_count(gb) >= ctx->data_size){
188
            *last = 1;
189
            return 0;
190
        }
191
        if(t == 16) {
192
            t2 = get_unary(gb);
193
            if(t2 < 2) t += t2;
194
            else t += get_bits(gb, t2 - 1) | (1 << (t2 - 1));
195
        }
196
197
        if(ctx->one){
198
            ctx->one = t&1;
199
            t = (t>>1) + 1;
200
        }else{
201
            ctx->one = t&1;
202
            t >>= 1;
203
        }
204
        ctx->zero = !ctx->one;
205
    }
206
207
    if(!t){
208
        base = 0;
209
        add = GET_MED(0) - 1;
210
        DEC_MED(0);
211
    }else if(t == 1){
212
        base = GET_MED(0);
213
        add = GET_MED(1) - 1;
214
        INC_MED(0);
215
        DEC_MED(1);
216
    }else if(t == 2){
217
        base = GET_MED(0) + GET_MED(1);
218
        add = GET_MED(2) - 1;
219
        INC_MED(0);
220
        INC_MED(1);
221
        DEC_MED(2);
222
    }else{
223
        base = GET_MED(0) + GET_MED(1) + GET_MED(2) * (t - 2);
224
        add = GET_MED(2) - 1;
225
        INC_MED(0);
226
        INC_MED(1);
227
        INC_MED(2);
228
    }
229
    ret = base + get_tail(gb, add);
230
    sign = get_bits1(gb);
231
    return sign ? ~ret : ret;
232
}
233
234
static int wv_unpack_stereo(WavpackContext *s, GetBitContext *gb, int16_t *dst)
235
{
236
    int i, j, count = 0;
237
    int last, t;
238
    int A, B, L, L2, R, R2;
239
    int pos = 0;
240
    uint32_t crc = 0xFFFFFFFF;
241
242
    s->one = s->zero = s->zeroes = 0;
243
    do{
244
        L = wv_get_value(s, gb, s->median, &last);
245
        if(last) break;
246
        R = wv_get_value(s, gb, s->median + 3, &last);
247
        if(last) break;
248
        for(i = 0; i < s->terms; i++){
249
            t = s->decorr[i].value;
250
            j = 0;
251
            if(t > 0){
252
                if(t > 8){
253
                    if(t & 1){
254
                        A = 2 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1];
255
                        B = 2 * s->decorr[i].samplesB[0] - s->decorr[i].samplesB[1];
256
                    }else{
257
                        A = (3 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1]) >> 1;
258
                        B = (3 * s->decorr[i].samplesB[0] - s->decorr[i].samplesB[1]) >> 1;
259
                    }
260
                    s->decorr[i].samplesA[1] = s->decorr[i].samplesA[0];
261
                    s->decorr[i].samplesB[1] = s->decorr[i].samplesB[0];
262
                    j = 0;
263
                }else{
264
                    A = s->decorr[i].samplesA[pos];
265
                    B = s->decorr[i].samplesB[pos];
266
                    j = (pos + t) & 7;
267
                }
268
                L2 = L + ((s->decorr[i].weightA * A + 512) >> 10);
269
                R2 = R + ((s->decorr[i].weightB * B + 512) >> 10);
270
                if(A && L) s->decorr[i].weightA -= ((((L ^ A) >> 30) & 2) - 1) * s->decorr[i].delta;
271
                if(B && R) s->decorr[i].weightB -= ((((R ^ B) >> 30) & 2) - 1) * s->decorr[i].delta;
272
                s->decorr[i].samplesA[j] = L = L2;
273
                s->decorr[i].samplesB[j] = R = R2;
274
            }else if(t == -1){
275
                L2 = L + ((s->decorr[i].weightA * s->decorr[i].samplesA[0] + 512) >> 10);
276
                UPDATE_WEIGHT_CLIP(s->decorr[i].weightA, s->decorr[i].delta, s->decorr[i].samplesA[0], L);
277
                L = L2;
278
                R2 = R + ((s->decorr[i].weightB * L2 + 512) >> 10);
279
                UPDATE_WEIGHT_CLIP(s->decorr[i].weightB, s->decorr[i].delta, L2, R);
280
                R = R2;
281
                s->decorr[i].samplesA[0] = R;
282
            }else{
283
                R2 = R + ((s->decorr[i].weightB * s->decorr[i].samplesB[0] + 512) >> 10);
284
                UPDATE_WEIGHT_CLIP(s->decorr[i].weightB, s->decorr[i].delta, s->decorr[i].samplesB[0], R);
285
                R = R2;
286
287
                if(t == -3){
288
                    R2 = s->decorr[i].samplesA[0];
289
                    s->decorr[i].samplesA[0] = R;
290
                }
291
292
                L2 = L + ((s->decorr[i].weightA * R2 + 512) >> 10);
293
                UPDATE_WEIGHT_CLIP(s->decorr[i].weightA, s->decorr[i].delta, R2, L);
294
                L = L2;
295
                s->decorr[i].samplesB[0] = L;
296
            }
297
        }
298
        pos = (pos + 1) & 7;
299
        if(s->joint)
300
            L += (R -= (L >> 1));
301
        crc = (crc * 3 + L) * 3 + R;
302
        *dst++ = L;
303
        *dst++ = R;
304
305
        count++;
306
    }while(!last && count < s->samples);
307
308
    if(crc != s->CRC){
309
        av_log(s->avctx, AV_LOG_ERROR, "CRC error\n");
310
        return -1;
311
    }
312
    return count * 2;
313
}
314
315
static int wv_unpack_mono(WavpackContext *s, GetBitContext *gb, int16_t *dst)
316
{
317
    int i, j, count = 0;
318
    int last, t;
319
    int A, S, T;
320
    int pos = 0;
321
    uint32_t crc = 0xFFFFFFFF;
322
323
    s->one = s->zero = s->zeroes = 0;
324
    do{
325
        T = wv_get_value(s, gb, s->median, &last);
326
        S = 0;
327
        if(last) break;
328
        for(i = 0; i < s->terms; i++){
329
            t = s->decorr[i].value;
330
            if(t > 8){
331
                if(t & 1)
332
                    A = 2 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1];
333
                else
334
                    A = (3 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1]) >> 1;
335
                s->decorr[i].samplesA[1] = s->decorr[i].samplesA[0];
336
                j = 0;
337
            }else{
338
                A = s->decorr[i].samplesA[pos];
339
                j = (pos + t) & 7;
340
            }
341
            S = T + ((s->decorr[i].weightA * A + 512) >> 10);
342
            if(A && T) s->decorr[i].weightA -= ((((T ^ A) >> 30) & 2) - 1) * s->decorr[i].delta;
343
            s->decorr[i].samplesA[j] = T = S;
344
        }
345
        pos = (pos + 1) & 7;
346
        crc = crc * 3 + S;
347
        *dst++ = S;
348
        count++;
349
    }while(!last && count < s->samples);
350
351
    if(crc != s->CRC){
352
        av_log(s->avctx, AV_LOG_ERROR, "CRC error\n");
353
        return -1;
354
    }
355
    return count;
356
}
357
358
static int wavpack_decode_init(AVCodecContext *avctx)
359
{
360
    WavpackContext *s = avctx->priv_data;
361
362
    s->avctx = avctx;
363
    s->stereo = (avctx->channels == 2);
364
365
    return 0;
366
}
367
368
static int wavpack_decode_close(AVCodecContext *avctx)
369
{
370
//    WavpackContext *s = avctx->priv_data;
371
372
    return 0;
373
}
374
375
static int wavpack_decode_frame(AVCodecContext *avctx,
376
                            void *data, int *data_size,
377
                            uint8_t *buf, int buf_size)
378
{
379
    WavpackContext *s = avctx->priv_data;
380
    int16_t *samples = data;
381
    int samplecount;
382
    int got_terms = 0, got_weights = 0, got_samples = 0, got_entropy = 0, got_bs = 0;
383
    uint8_t* buf_end = buf + buf_size;
384
    int i, j, id, size, ssize, weights, t;
385
386
    if (buf_size == 0) return 0;
387
388
    memset(s->decorr, 0, MAX_TERMS * sizeof(Decorr));
389
390
    s->samples = LE_32(buf); buf += 4;
391 a8789714 Kostya Shishkov
    if(!s->samples) return buf_size;
392 4ec0beaa Kostya Shishkov
    /* should not happen but who knows */
393
    if(s->samples * 2 * avctx->channels > AVCODEC_MAX_AUDIO_FRAME_SIZE){
394
        av_log(avctx, AV_LOG_ERROR, "Packet size is too big to be handled in lavc!\n");
395
        return -1;
396
    }
397 730581f3 Kostya Shishkov
    s->joint = LE_32(buf) & WV_JOINT; buf += 4;
398
    s->CRC = LE_32(buf); buf += 4;
399
    // parse metadata blocks
400
    while(buf < buf_end){
401
        id = *buf++;
402
        size = *buf++;
403
        if(id & WP_IDF_LONG) {
404
            size |= (*buf++) << 8;
405
            size |= (*buf++) << 16;
406
        }
407
        size <<= 1; // size is specified in words
408
        ssize = size;
409
        if(id & WP_IDF_ODD) size--;
410
        if(size < 0){
411
            av_log(avctx, AV_LOG_ERROR, "Got incorrect block %02X with size %i\n", id, size);
412
            break;
413
        }
414
        if(buf + ssize > buf_end){
415
            av_log(avctx, AV_LOG_ERROR, "Block size %i is out of bounds\n", size);
416
            break;
417
        }
418
        if(id & WP_IDF_IGNORE){
419
            buf += ssize;
420
            continue;
421
        }
422
        switch(id & WP_IDF_MASK){
423
        case WP_ID_DECTERMS:
424
            s->terms = size;
425
            if(s->terms > MAX_TERMS){
426
                av_log(avctx, AV_LOG_ERROR, "Too many decorrelation terms\n");
427
                buf += ssize;
428
                continue;
429
            }
430
            for(i = 0; i < s->terms; i++) {
431
                s->decorr[s->terms - i - 1].value = (*buf & 0x1F) - 5;
432
                s->decorr[s->terms - i - 1].delta = *buf >> 5;
433
                buf++;
434
            }
435
            got_terms = 1;
436
            break;
437
        case WP_ID_DECWEIGHTS:
438
            if(!got_terms){
439
                av_log(avctx, AV_LOG_ERROR, "No decorrelation terms met\n");
440
                continue;
441
            }
442
            weights = size >> s->stereo;
443
            if(weights > MAX_TERMS || weights > s->terms){
444
                av_log(avctx, AV_LOG_ERROR, "Too many decorrelation weights\n");
445
                buf += ssize;
446
                continue;
447
            }
448
            for(i = 0; i < weights; i++) {
449
                t = (int8_t)(*buf++);
450
                s->decorr[s->terms - i - 1].weightA = t << 3;
451
                if(s->decorr[s->terms - i - 1].weightA > 0)
452
                    s->decorr[s->terms - i - 1].weightA += (s->decorr[s->terms - i - 1].weightA + 64) >> 7;
453
                if(s->stereo){
454
                    t = (int8_t)(*buf++);
455
                    s->decorr[s->terms - i - 1].weightB = t << 3;
456
                    if(s->decorr[s->terms - i - 1].weightB > 0)
457
                        s->decorr[s->terms - i - 1].weightB += (s->decorr[s->terms - i - 1].weightB + 64) >> 7;
458
                }
459
            }
460
            got_weights = 1;
461
            break;
462
        case WP_ID_DECSAMPLES:
463
            if(!got_terms){
464
                av_log(avctx, AV_LOG_ERROR, "No decorrelation terms met\n");
465
                continue;
466
            }
467
            t = 0;
468
            for(i = s->terms - 1; (i >= 0) && (t < size); i--) {
469
                if(s->decorr[i].value > 8){
470
                    s->decorr[i].samplesA[0] = wp_exp2(LE_16(buf)); buf += 2;
471
                    s->decorr[i].samplesA[1] = wp_exp2(LE_16(buf)); buf += 2;
472
                    if(s->stereo){
473
                        s->decorr[i].samplesB[0] = wp_exp2(LE_16(buf)); buf += 2;
474
                        s->decorr[i].samplesB[1] = wp_exp2(LE_16(buf)); buf += 2;
475
                        t += 4;
476
                    }
477
                    t += 4;
478
                }else if(s->decorr[i].value < 0){
479
                    s->decorr[i].samplesA[0] = wp_exp2(LE_16(buf)); buf += 2;
480
                    s->decorr[i].samplesB[0] = wp_exp2(LE_16(buf)); buf += 2;
481
                    t += 4;
482
                }else{
483
                    for(j = 0; j < s->decorr[i].value; j++){
484
                        s->decorr[i].samplesA[j] = wp_exp2(LE_16(buf)); buf += 2;
485
                        if(s->stereo){
486
                            s->decorr[i].samplesB[j] = wp_exp2(LE_16(buf)); buf += 2;
487
                        }
488
                    }
489
                    t += s->decorr[i].value * 2 * avctx->channels;
490
                }
491
            }
492
            got_samples = 1;
493
            break;
494
        case WP_ID_ENTROPY:
495
            if(size != 6 * avctx->channels){
496
                av_log(avctx, AV_LOG_ERROR, "Entropy vars size should be %i, got %i", 6 * avctx->channels, size);
497
                buf += ssize;
498
                continue;
499
            }
500
            for(i = 0; i < 3 * avctx->channels; i++){
501
                s->median[i] = wp_exp2(LE_16(buf));
502
                buf += 2;
503
            }
504
            got_entropy = 1;
505
            break;
506
        case WP_ID_DATA:
507
            init_get_bits(&s->gb, buf, size * 8);
508
            s->data_size = size * 8;
509
            buf += size;
510
            got_bs = 1;
511
            break;
512
        default:
513
            buf += size;
514
        }
515
        if(id & WP_IDF_ODD) buf++;
516
    }
517
    if(!got_terms){
518
        av_log(avctx, AV_LOG_ERROR, "No block with decorrelation terms\n");
519
        return -1;
520
    }
521
    if(!got_weights){
522
        av_log(avctx, AV_LOG_ERROR, "No block with decorrelation weights\n");
523
        return -1;
524
    }
525
    if(!got_samples){
526
        av_log(avctx, AV_LOG_ERROR, "No block with decorrelation samples\n");
527
        return -1;
528
    }
529
    if(!got_entropy){
530
        av_log(avctx, AV_LOG_ERROR, "No block with entropy info\n");
531
        return -1;
532
    }
533
    if(!got_bs){
534
        av_log(avctx, AV_LOG_ERROR, "Packed samples not found\n");
535
        return -1;
536
    }
537
538
    if(s->stereo)
539
        samplecount = wv_unpack_stereo(s, &s->gb, samples);
540
    else
541
        samplecount = wv_unpack_mono(s, &s->gb, samples);
542
    *data_size = samplecount * 2;
543
544
    return buf_size;
545
}
546
547
AVCodec wavpack_decoder = {
548
    "wavpack",
549
    CODEC_TYPE_AUDIO,
550
    CODEC_ID_WAVPACK,
551
    sizeof(WavpackContext),
552
    wavpack_decode_init,
553
    NULL,
554
    wavpack_decode_close,
555
    wavpack_decode_frame,
556
};