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1
/*
2
 * DV decoder
3
 * Copyright (c) 2002 Fabrice Bellard.
4
 *
5
 * This library is free software; you can redistribute it and/or
6
 * modify it under the terms of the GNU Lesser General Public
7
 * License as published by the Free Software Foundation; either
8
 * version 2 of the License, or (at your option) any later version.
9
 *
10
 * This library is distributed in the hope that it will be useful,
11
 * 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.
14
 *
15
 * 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
18
 */
19
#include "avcodec.h"
20
#include "dsputil.h"
21
#include "mpegvideo.h"
22
#include "simple_idct.h"
23

    
24
#define NTSC_FRAME_SIZE 120000
25
#define PAL_FRAME_SIZE  144000
26

    
27
#define TEX_VLC_BITS 9
28

    
29
typedef struct DVVideoDecodeContext {
30
    AVCodecContext *avctx;
31
    GetBitContext gb;
32
    VLC *vlc;
33
    int sampling_411; /* 0 = 420, 1 = 411 */
34
    int width, height;
35
    UINT8 *current_picture[3]; /* picture structure */
36
    int linesize[3];
37
    DCTELEM block[5*6][64] __align8;
38
    UINT8 dv_zigzag[2][64];
39
    UINT8 idct_permutation[64];
40
    /* XXX: move it to static storage ? */
41
    UINT8 dv_shift[2][22][64];
42
    void (*idct_put[2])(UINT8 *dest, int line_size, DCTELEM *block);
43
} DVVideoDecodeContext;
44

    
45
#include "dvdata.h"
46

    
47
static VLC dv_vlc;
48
/* XXX: also include quantization */
49
static RL_VLC_ELEM *dv_rl_vlc[1];
50

    
51
static void dv_build_unquantize_tables(DVVideoDecodeContext *s)
52
{
53
    int i, q, j;
54

    
55
    /* NOTE: max left shift is 6 */
56
    for(q = 0; q < 22; q++) {
57
        /* 88 unquant */
58
        for(i = 1; i < 64; i++) {
59
            /* 88 table */
60
            j = s->idct_permutation[i];
61
            s->dv_shift[0][q][j] =
62
                dv_quant_shifts[q][dv_88_areas[i]] + 1;
63
        }
64
        
65
        /* 248 unquant */
66
        for(i = 1; i < 64; i++) {
67
            /* 248 table */
68
            s->dv_shift[1][q][i] =  
69
                    dv_quant_shifts[q][dv_248_areas[i]] + 1;
70
        }
71
    }
72
}
73

    
74
static int dvvideo_decode_init(AVCodecContext *avctx)
75
{
76
    DVVideoDecodeContext *s = avctx->priv_data;
77
    MpegEncContext s2;
78
    static int done;
79

    
80
    if (!done) {
81
        int i;
82

    
83
        done = 1;
84

    
85
        /* NOTE: as a trick, we use the fact the no codes are unused
86
           to accelerate the parsing of partial codes */
87
        init_vlc(&dv_vlc, TEX_VLC_BITS, NB_DV_VLC, 
88
                 dv_vlc_len, 1, 1, dv_vlc_bits, 2, 2);
89

    
90
        dv_rl_vlc[0] = av_malloc(dv_vlc.table_size * sizeof(RL_VLC_ELEM));
91
        for(i = 0; i < dv_vlc.table_size; i++){
92
            int code= dv_vlc.table[i][0];
93
            int len = dv_vlc.table[i][1];
94
            int level, run;
95
        
96
            if(len<0){ //more bits needed
97
                run= 0;
98
                level= code;
99
            } else if (code == (NB_DV_VLC - 1)) {
100
                /* EOB */
101
                run = 0;
102
                level = 256;
103
            } else {
104
                run=   dv_vlc_run[code] + 1;
105
                level= dv_vlc_level[code];
106
            }
107
            dv_rl_vlc[0][i].len = len;
108
            dv_rl_vlc[0][i].level = level;
109
            dv_rl_vlc[0][i].run = run;
110
        }
111
    }
112

    
113
    /* ugly way to get the idct & scantable */
114
    /* XXX: fix it */
115
    memset(&s2, 0, sizeof(MpegEncContext));
116
    s2.avctx = avctx;
117
    if (DCT_common_init(&s2) < 0)
118
       return -1;
119

    
120
    s->idct_put[0] = s2.idct_put;
121
    memcpy(s->idct_permutation, s2.idct_permutation, 64);
122
    memcpy(s->dv_zigzag[0], s2.intra_scantable.permutated, 64);
123

    
124
    /* XXX: use MMX also for idct248 */
125
    s->idct_put[1] = simple_idct248_put;
126
    memcpy(s->dv_zigzag[1], dv_248_zigzag, 64);
127

    
128
    /* XXX: do it only for constant case */
129
    dv_build_unquantize_tables(s);
130

    
131
    return 0;
132
}
133

    
134
//#define VLC_DEBUG
135

    
136
typedef struct BlockInfo {
137
    const UINT8 *shift_table;
138
    const UINT8 *scan_table;
139
    UINT8 pos; /* position in block */
140
    UINT8 eob_reached; /* true if EOB has been reached */
141
    UINT8 dct_mode;
142
    UINT8 partial_bit_count;
143
    UINT16 partial_bit_buffer;
144
    int shift_offset;
145
} BlockInfo;
146

    
147
/* block size in bits */
148
static const UINT16 block_sizes[6] = {
149
    112, 112, 112, 112, 80, 80
150
};
151

    
152
#ifndef ALT_BITSTREAM_READER
153
#error only works with ALT_BITSTREAM_READER
154
#endif
155

    
156
/* decode ac coefs */
157
static void dv_decode_ac(DVVideoDecodeContext *s, 
158
                         BlockInfo *mb, INT16 *block, int last_index)
159
{
160
    int last_re_index;
161
    int shift_offset = mb->shift_offset;
162
    const UINT8 *scan_table = mb->scan_table;
163
    const UINT8 *shift_table = mb->shift_table;
164
    int pos = mb->pos;
165
    int level, pos1, sign, run;
166
    int partial_bit_count;
167

    
168
    OPEN_READER(re, &s->gb);
169
    
170
#ifdef VLC_DEBUG
171
    printf("start\n");
172
#endif
173

    
174
    /* if we must parse a partial vlc, we do it here */
175
    partial_bit_count = mb->partial_bit_count;
176
    if (partial_bit_count > 0) {
177
        UINT8 buf[4];
178
        UINT32 v;
179
        int l, l1;
180
        GetBitContext gb1;
181

    
182
        /* build the dummy bit buffer */
183
        l = 16 - partial_bit_count;
184
        UPDATE_CACHE(re, &s->gb);
185
#ifdef VLC_DEBUG
186
        printf("show=%04x\n", SHOW_UBITS(re, &s->gb, 16));
187
#endif
188
        v = (mb->partial_bit_buffer << l) | SHOW_UBITS(re, &s->gb, l);
189
        buf[0] = v >> 8;
190
        buf[1] = v;
191
#ifdef VLC_DEBUG
192
        printf("v=%04x cnt=%d %04x\n", 
193
               v, partial_bit_count, (mb->partial_bit_buffer << l));
194
#endif
195
        /* try to read the codeword */
196
        init_get_bits(&gb1, buf, 4);
197
        {
198
            OPEN_READER(re1, &gb1);
199
            UPDATE_CACHE(re1, &gb1);
200
            GET_RL_VLC(level, run, re1, &gb1, dv_rl_vlc[0], 
201
                       TEX_VLC_BITS, 2);
202
            l = re1_index;
203
            CLOSE_READER(re1, &gb1);
204
        }
205
#ifdef VLC_DEBUG
206
        printf("****run=%d level=%d size=%d\n", run, level, l);
207
#endif
208
        /* compute codeword length */
209
        l1 = (level != 256 && level != 0);
210
        /* if too long, we cannot parse */
211
        l -= partial_bit_count;
212
        if ((re_index + l + l1) > last_index)
213
            return;
214
        /* skip read bits */
215
        last_re_index = 0; /* avoid warning */
216
        re_index += l;
217
        /* by definition, if we can read the vlc, all partial bits
218
           will be read (otherwise we could have read the vlc before) */
219
        mb->partial_bit_count = 0;
220
        UPDATE_CACHE(re, &s->gb);
221
        goto handle_vlc;
222
    }
223

    
224
    /* get the AC coefficients until last_index is reached */
225
    for(;;) {
226
        UPDATE_CACHE(re, &s->gb);
227
#ifdef VLC_DEBUG
228
        printf("%2d: bits=%04x index=%d\n", 
229
               pos, SHOW_UBITS(re, &s->gb, 16), re_index);
230
#endif
231
        last_re_index = re_index;
232
        GET_RL_VLC(level, run, re, &s->gb, dv_rl_vlc[0], 
233
                   TEX_VLC_BITS, 2);
234
    handle_vlc:
235
#ifdef VLC_DEBUG
236
        printf("run=%d level=%d\n", run, level);
237
#endif
238
        if (level == 256) {
239
            if (re_index > last_index) {
240
            cannot_read:
241
                /* put position before read code */
242
                re_index = last_re_index;
243
                mb->eob_reached = 0;
244
                break;
245
            }
246
            /* EOB */
247
            mb->eob_reached = 1;
248
            break;
249
        } else if (level != 0) {
250
            if ((re_index + 1) > last_index)
251
                goto cannot_read;
252
            sign = SHOW_SBITS(re, &s->gb, 1);
253
            level = (level ^ sign) - sign;
254
            LAST_SKIP_BITS(re, &s->gb, 1);
255
            pos += run;
256
            /* error */
257
            if (pos >= 64) {
258
                goto read_error;
259
            }
260
            pos1 = scan_table[pos];
261
            level = level << (shift_table[pos1] + shift_offset);
262
            block[pos1] = level;
263
            //            printf("run=%d level=%d shift=%d\n", run, level, shift_table[pos1]);
264
        } else {
265
            if (re_index > last_index)
266
                goto cannot_read;
267
            /* level is zero: means run without coding. No
268
               sign is coded */
269
            pos += run;
270
            /* error */
271
            if (pos >= 64) {
272
            read_error:
273
#if defined(VLC_DEBUG) || 1
274
                printf("error pos=%d\n", pos);
275
#endif
276
                /* for errors, we consider the eob is reached */
277
                mb->eob_reached = 1;
278
                break;
279
            }
280
        }
281
    }
282
    CLOSE_READER(re, &s->gb);
283
    mb->pos = pos;
284
}
285

    
286
static inline void bit_copy(PutBitContext *pb, GetBitContext *gb, int bits_left)
287
{
288
    while (bits_left >= 16) {
289
        put_bits(pb, 16, get_bits(gb, 16));
290
        bits_left -= 16;
291
    }
292
    if (bits_left > 0) {
293
        put_bits(pb, bits_left, get_bits(gb, bits_left));
294
    }
295
}
296

    
297
/* mb_x and mb_y are in units of 8 pixels */
298
static inline void dv_decode_video_segment(DVVideoDecodeContext *s, 
299
                                           UINT8 *buf_ptr1, 
300
                                           const UINT16 *mb_pos_ptr)
301
{
302
    int quant, dc, dct_mode, class1, j;
303
    int mb_index, mb_x, mb_y, v, last_index;
304
    DCTELEM *block, *block1;
305
    int c_offset, bits_left;
306
    UINT8 *y_ptr;
307
    BlockInfo mb_data[5 * 6], *mb, *mb1;
308
    void (*idct_put)(UINT8 *dest, int line_size, DCTELEM *block);
309
    UINT8 *buf_ptr;
310
    PutBitContext pb, vs_pb;
311
    UINT8 mb_bit_buffer[80 + 4]; /* allow some slack */
312
    int mb_bit_count;
313
    UINT8 vs_bit_buffer[5 * 80 + 4]; /* allow some slack */
314
    int vs_bit_count;
315
    
316
    memset(s->block, 0, sizeof(s->block));
317

    
318
    /* pass 1 : read DC and AC coefficients in blocks */
319
    buf_ptr = buf_ptr1;
320
    block1 = &s->block[0][0];
321
    mb1 = mb_data;
322
    init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80, NULL, NULL);
323
    vs_bit_count = 0;
324
    for(mb_index = 0; mb_index < 5; mb_index++) {
325
        /* skip header */
326
        quant = buf_ptr[3] & 0x0f;
327
        buf_ptr += 4;
328
        init_put_bits(&pb, mb_bit_buffer, 80, NULL, NULL);
329
        mb_bit_count = 0;
330
        mb = mb1;
331
        block = block1;
332
        for(j = 0;j < 6; j++) {
333
            /* NOTE: size is not important here */
334
            init_get_bits(&s->gb, buf_ptr, 14);
335
            
336
            /* get the dc */
337
            dc = get_bits(&s->gb, 9);
338
            dc = (dc << (32 - 9)) >> (32 - 9);
339
            dct_mode = get_bits1(&s->gb);
340
            mb->dct_mode = dct_mode;
341
            mb->scan_table = s->dv_zigzag[dct_mode];
342
            class1 = get_bits(&s->gb, 2);
343
            mb->shift_offset = (class1 == 3);
344
            mb->shift_table = s->dv_shift[dct_mode]
345
                [quant + dv_quant_offset[class1]];
346
            dc = dc << 2;
347
            /* convert to unsigned because 128 is not added in the
348
               standard IDCT */
349
            dc += 1024;
350
            block[0] = dc;
351
            last_index = block_sizes[j];
352
            buf_ptr += last_index >> 3;
353
            mb->pos = 0;
354
            mb->partial_bit_count = 0;
355

    
356
            dv_decode_ac(s, mb, block, last_index);
357

    
358
            /* write the remaining bits  in a new buffer only if the
359
               block is finished */
360
            bits_left = last_index - s->gb.index;
361
            if (mb->eob_reached) {
362
                mb->partial_bit_count = 0;
363
                mb_bit_count += bits_left;
364
                bit_copy(&pb, &s->gb, bits_left);
365
            } else {
366
                /* should be < 16 bits otherwise a codeword could have
367
                   been parsed */
368
                mb->partial_bit_count = bits_left;
369
                mb->partial_bit_buffer = get_bits(&s->gb, bits_left);
370
            }
371
            block += 64;
372
            mb++;
373
        }
374
        
375
        flush_put_bits(&pb);
376

    
377
        /* pass 2 : we can do it just after */
378
#ifdef VLC_DEBUG
379
        printf("***pass 2 size=%d\n", mb_bit_count);
380
#endif
381
        block = block1;
382
        mb = mb1;
383
        init_get_bits(&s->gb, mb_bit_buffer, 80);
384
        for(j = 0;j < 6; j++) {
385
            if (!mb->eob_reached && s->gb.index < mb_bit_count) {
386
                dv_decode_ac(s, mb, block, mb_bit_count);
387
                /* if still not finished, no need to parse other blocks */
388
                if (!mb->eob_reached) {
389
                    /* we could not parse the current AC coefficient,
390
                       so we add the remaining bytes */
391
                    bits_left = mb_bit_count - s->gb.index;
392
                    if (bits_left > 0) {
393
                        mb->partial_bit_count += bits_left;
394
                        mb->partial_bit_buffer = 
395
                            (mb->partial_bit_buffer << bits_left) | 
396
                            get_bits(&s->gb, bits_left);
397
                    }
398
                    goto next_mb;
399
                }
400
            }
401
            block += 64;
402
            mb++;
403
        }
404
        /* all blocks are finished, so the extra bytes can be used at
405
           the video segment level */
406
        bits_left = mb_bit_count - s->gb.index;
407
        vs_bit_count += bits_left;
408
        bit_copy(&vs_pb, &s->gb, bits_left);
409
    next_mb:
410
        mb1 += 6;
411
        block1 += 6 * 64;
412
    }
413

    
414
    /* we need a pass other the whole video segment */
415
    flush_put_bits(&vs_pb);
416
        
417
#ifdef VLC_DEBUG
418
    printf("***pass 3 size=%d\n", vs_bit_count);
419
#endif
420
    block = &s->block[0][0];
421
    mb = mb_data;
422
    init_get_bits(&s->gb, vs_bit_buffer, 5 * 80);
423
    for(mb_index = 0; mb_index < 5; mb_index++) {
424
        for(j = 0;j < 6; j++) {
425
            if (!mb->eob_reached) {
426
#ifdef VLC_DEBUG
427
                printf("start %d:%d\n", mb_index, j);
428
#endif
429
                dv_decode_ac(s, mb, block, vs_bit_count);
430
            }
431
            block += 64;
432
            mb++;
433
        }
434
    }
435
    
436
    /* compute idct and place blocks */
437
    block = &s->block[0][0];
438
    mb = mb_data;
439
    for(mb_index = 0; mb_index < 5; mb_index++) {
440
        v = *mb_pos_ptr++;
441
        mb_x = v & 0xff;
442
        mb_y = v >> 8;
443
        y_ptr = s->current_picture[0] + (mb_y * s->linesize[0] * 8) + (mb_x * 8);
444
        if (s->sampling_411)
445
            c_offset = (mb_y * s->linesize[1] * 8) + ((mb_x >> 2) * 8);
446
        else
447
            c_offset = ((mb_y >> 1) * s->linesize[1] * 8) + ((mb_x >> 1) * 8);
448
        for(j = 0;j < 6; j++) {
449
            idct_put = s->idct_put[mb->dct_mode];
450
            if (j < 4) {
451
                if (s->sampling_411) {
452
                    idct_put(y_ptr + (j * 8), s->linesize[0], block);
453
                } else {
454
                    idct_put(y_ptr + ((j & 1) * 8) + ((j >> 1) * 8 * s->linesize[0]),
455
                             s->linesize[0], block);
456
                }
457
            } else {
458
                /* don't ask me why they inverted Cb and Cr ! */
459
                idct_put(s->current_picture[6 - j] + c_offset, 
460
                         s->linesize[6 - j], block);
461
            }
462
            block += 64;
463
            mb++;
464
        }
465
    }
466
}
467

    
468

    
469
/* NOTE: exactly one frame must be given (120000 bytes for NTSC,
470
   144000 bytes for PAL) */
471
static int dvvideo_decode_frame(AVCodecContext *avctx, 
472
                                 void *data, int *data_size,
473
                                 UINT8 *buf, int buf_size)
474
{
475
    DVVideoDecodeContext *s = avctx->priv_data;
476
    int sct, dsf, apt, ds, nb_dif_segs, vs, size, width, height, i;
477
    UINT8 *buf_ptr;
478
    const UINT16 *mb_pos_ptr;
479
    AVPicture *picture;
480
    
481
    /* parse id */
482
    init_get_bits(&s->gb, buf, buf_size);
483
    sct = get_bits(&s->gb, 3);
484
    if (sct != 0)
485
        return -1;
486
    skip_bits(&s->gb, 5);
487
    get_bits(&s->gb, 4); /* dsn (sequence number */
488
    get_bits(&s->gb, 1); /* fsc (channel number) */
489
    skip_bits(&s->gb, 3);
490
    get_bits(&s->gb, 8); /* dbn (diff block number 0-134) */
491

    
492
    dsf = get_bits(&s->gb, 1); /* 0 = NTSC 1 = PAL */
493
    if (get_bits(&s->gb, 1) != 0)
494
        return -1;
495
    skip_bits(&s->gb, 11);
496
    apt = get_bits(&s->gb, 3); /* apt */
497

    
498
    get_bits(&s->gb, 1); /* tf1 */
499
    skip_bits(&s->gb, 4);
500
    get_bits(&s->gb, 3); /* ap1 */
501

    
502
    get_bits(&s->gb, 1); /* tf2 */
503
    skip_bits(&s->gb, 4);
504
    get_bits(&s->gb, 3); /* ap2 */
505

    
506
    get_bits(&s->gb, 1); /* tf3 */
507
    skip_bits(&s->gb, 4);
508
    get_bits(&s->gb, 3); /* ap3 */
509
    
510
    /* init size */
511
    width = 720;
512
    if (dsf) {
513
        if (buf_size != PAL_FRAME_SIZE)
514
            return -1;
515
        height = 576;
516
        nb_dif_segs = 12;
517
    } else {
518
        if (buf_size != NTSC_FRAME_SIZE)
519
            return -1;
520
        height = 480;
521
        nb_dif_segs = 10;
522
    }
523

    
524
    /* XXX: is it correct to assume that 420 is always used in PAL
525
       mode ? */
526
    s->sampling_411 = !dsf;
527
    if (s->sampling_411)
528
        mb_pos_ptr = dv_place_411;
529
    else
530
        mb_pos_ptr = dv_place_420;
531

    
532
    /* (re)alloc picture if needed */
533
    if (s->width != width || s->height != height) {
534
        for(i=0;i<3;i++)
535
            av_freep(&s->current_picture[i]);
536
        for(i=0;i<3;i++) {
537
            size = width * height;
538
            s->linesize[i] = width;
539
            if (i >= 1) {
540
                size >>= 2;
541
                s->linesize[i] >>= s->sampling_411 ? 2 : 1;
542
            }
543
            s->current_picture[i] = av_malloc(size);
544
            if (!s->current_picture[i])
545
                return -1;
546
        }
547
        s->width = width;
548
        s->height = height;
549
    }
550

    
551
    /* for each DIF segment */
552
    buf_ptr = buf;
553
    for (ds = 0; ds < nb_dif_segs; ds++) {
554
        buf_ptr += 6 * 80; /* skip DIF segment header */
555
        
556
        for(vs = 0; vs < 27; vs++) {
557
            if ((vs % 3) == 0) {
558
                /* skip audio block */
559
                buf_ptr += 80;
560
            }
561
            dv_decode_video_segment(s, buf_ptr, mb_pos_ptr);
562
            buf_ptr += 5 * 80;
563
            mb_pos_ptr += 5;
564
        }
565
    }
566

    
567
    /* return image */
568
    avctx->width = width;
569
    avctx->height = height;
570
    if (s->sampling_411)
571
        avctx->pix_fmt = PIX_FMT_YUV411P;
572
    else
573
        avctx->pix_fmt = PIX_FMT_YUV420P;
574
    if (dsf)
575
        avctx->frame_rate = 25 * FRAME_RATE_BASE;
576
    else
577
        avctx->frame_rate = 30 * FRAME_RATE_BASE;
578
    *data_size = sizeof(AVPicture);
579
    picture = data;
580
    for(i=0;i<3;i++) {
581
        picture->data[i] = s->current_picture[i];
582
        picture->linesize[i] = s->linesize[i];
583
    }
584
    return buf_size;
585
}
586

    
587
static int dvvideo_decode_end(AVCodecContext *avctx)
588
{
589
    DVVideoDecodeContext *s = avctx->priv_data;
590
    int i;
591

    
592
    for(i=0;i<3;i++)
593
        av_freep(&s->current_picture[i]);
594
    return 0;
595
}
596

    
597
AVCodec dvvideo_decoder = {
598
    "dvvideo",
599
    CODEC_TYPE_VIDEO,
600
    CODEC_ID_DVVIDEO,
601
    sizeof(DVVideoDecodeContext),
602
    dvvideo_decode_init,
603
    NULL,
604
    dvvideo_decode_end,
605
    dvvideo_decode_frame,
606
    0,
607
    NULL
608
};
609

    
610
typedef struct DVAudioDecodeContext {
611
    AVCodecContext *avctx;
612
    GetBitContext gb;
613

    
614
} DVAudioDecodeContext;
615

    
616
static int dvaudio_decode_init(AVCodecContext *avctx)
617
{
618
    //    DVAudioDecodeContext *s = avctx->priv_data;
619
    return 0;
620
}
621

    
622
/* NOTE: exactly one frame must be given (120000 bytes for NTSC,
623
   144000 bytes for PAL) */
624
static int dvaudio_decode_frame(AVCodecContext *avctx, 
625
                                 void *data, int *data_size,
626
                                 UINT8 *buf, int buf_size)
627
{
628
    //    DVAudioDecodeContext *s = avctx->priv_data;
629
    return buf_size;
630
}
631

    
632
static int dvaudio_decode_end(AVCodecContext *avctx)
633
{
634
    //    DVAudioDecodeContext *s = avctx->priv_data;
635
    return 0;
636
}
637

    
638
AVCodec dvaudio_decoder = {
639
    "dvaudio",
640
    CODEC_TYPE_AUDIO,
641
    CODEC_ID_DVAUDIO,
642
    sizeof(DVAudioDecodeContext),
643
    dvaudio_decode_init,
644
    NULL,
645
    dvaudio_decode_end,
646
    dvaudio_decode_frame,
647
    0,
648
    NULL
649
};