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ffmpeg / libavcodec / h263dec.c @ aef95c8c

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1
/*
2
 * H.263 decoder
3
 * Copyright (c) 2001 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
16
 * License along with this library; if not, write to the Free Software
17
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18
 */
19
 
20
/**
21
 * @file h263dec.c
22
 * H.263 decoder.
23
 */
24
 
25
#include "avcodec.h"
26
#include "dsputil.h"
27
#include "mpegvideo.h"
28

    
29
//#define DEBUG
30
//#define PRINT_FRAME_TIME
31
#ifdef PRINT_FRAME_TIME
32
static inline long long rdtsc()
33
{
34
        long long l;
35
        asm volatile(        "rdtsc\n\t"
36
                : "=A" (l)
37
        );
38
//        printf("%d\n", int(l/1000));
39
        return l;
40
}
41
#endif
42

    
43
int ff_h263_decode_init(AVCodecContext *avctx)
44
{
45
    MpegEncContext *s = avctx->priv_data;
46

    
47
    s->avctx = avctx;
48
    s->out_format = FMT_H263;
49

    
50
    s->width = avctx->width;
51
    s->height = avctx->height;
52
    s->workaround_bugs= avctx->workaround_bugs;
53

    
54
    // set defaults
55
    s->quant_precision=5;
56
    s->progressive_sequence=1;
57
    s->decode_mb= ff_h263_decode_mb;
58
    s->low_delay= 1;
59
    avctx->pix_fmt= PIX_FMT_YUV420P;
60

    
61
    /* select sub codec */
62
    switch(avctx->codec->id) {
63
    case CODEC_ID_H263:
64
        s->gob_number = 0;
65
        break;
66
    case CODEC_ID_MPEG4:
67
        s->time_increment_bits = 4; /* default value for broken headers */
68
        s->h263_pred = 1;
69
        s->low_delay = 0; //default, might be overriden in the vol header during header parsing
70
        break;
71
    case CODEC_ID_MSMPEG4V1:
72
        s->h263_msmpeg4 = 1;
73
        s->h263_pred = 1;
74
        s->msmpeg4_version=1;
75
        break;
76
    case CODEC_ID_MSMPEG4V2:
77
        s->h263_msmpeg4 = 1;
78
        s->h263_pred = 1;
79
        s->msmpeg4_version=2;
80
        break;
81
    case CODEC_ID_MSMPEG4V3:
82
        s->h263_msmpeg4 = 1;
83
        s->h263_pred = 1;
84
        s->msmpeg4_version=3;
85
        break;
86
    case CODEC_ID_WMV1:
87
        s->h263_msmpeg4 = 1;
88
        s->h263_pred = 1;
89
        s->msmpeg4_version=4;
90
        break;
91
    case CODEC_ID_WMV2:
92
        s->h263_msmpeg4 = 1;
93
        s->h263_pred = 1;
94
        s->msmpeg4_version=5;
95
        break;
96
    case CODEC_ID_H263I:
97
        s->h263_intel = 1;
98
        break;
99
    default:
100
        return -1;
101
    }
102
    s->codec_id= avctx->codec->id;
103

    
104
    /* for h263, we allocate the images after having read the header */
105
    if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
106
        if (MPV_common_init(s) < 0)
107
            return -1;
108

    
109
    if (s->h263_msmpeg4)
110
        ff_msmpeg4_decode_init(s);
111
    else
112
        h263_decode_init_vlc(s);
113
    
114
    return 0;
115
}
116

    
117
int ff_h263_decode_end(AVCodecContext *avctx)
118
{
119
    MpegEncContext *s = avctx->priv_data;
120

    
121
    MPV_common_end(s);
122
    return 0;
123
}
124

    
125
/**
126
 * retunrs the number of bytes consumed for building the current frame
127
 */
128
static int get_consumed_bytes(MpegEncContext *s, int buf_size){
129
    int pos= (get_bits_count(&s->gb)+7)>>3;
130
    
131
    if(s->divx_packed){
132
        //we would have to scan through the whole buf to handle the weird reordering ...
133
        return buf_size; 
134
    }else if(s->flags&CODEC_FLAG_TRUNCATED){
135
        pos -= s->parse_context.last_index;
136
        if(pos<0) pos=0; // padding is not really read so this might be -1
137
        return pos;
138
    }else{
139
        if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
140
        if(pos+10>buf_size) pos=buf_size; // oops ;)
141

    
142
        return pos;
143
    }
144
}
145

    
146
static int decode_slice(MpegEncContext *s){
147
    const int part_mask= s->partitioned_frame ? (AC_END|AC_ERROR) : 0x7F;
148
    s->last_resync_gb= s->gb;
149
    s->first_slice_line= 1;
150
        
151
    s->resync_mb_x= s->mb_x;
152
    s->resync_mb_y= s->mb_y;
153

    
154
    s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
155
    s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
156
    
157
    if(s->partitioned_frame){
158
        const int qscale= s->qscale;
159

    
160
        if(s->codec_id==CODEC_ID_MPEG4){
161
            if(ff_mpeg4_decode_partitions(s) < 0)
162
                return -1; 
163
        }
164
        
165
        /* restore variables which where modified */
166
        s->first_slice_line=1;
167
        s->mb_x= s->resync_mb_x;
168
        s->mb_y= s->resync_mb_y;
169
        s->qscale= qscale;
170
        s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
171
        s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
172
    }
173

    
174
    for(; s->mb_y < s->mb_height; s->mb_y++) {
175
        /* per-row end of slice checks */
176
        if(s->msmpeg4_version){
177
            if(s->resync_mb_y + s->slice_height == s->mb_y){
178
                ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_END|DC_END|MV_END);
179

    
180
                return 0;
181
            }
182
        }
183
        
184
        if(s->msmpeg4_version==1){
185
            s->last_dc[0]=
186
            s->last_dc[1]=
187
            s->last_dc[2]= 128;
188
        }
189
    
190
        ff_init_block_index(s);
191
        for(; s->mb_x < s->mb_width; s->mb_x++) {
192
            int ret;
193

    
194
            ff_update_block_index(s);
195

    
196
            if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
197
                s->first_slice_line=0; 
198
            }
199

    
200
            /* DCT & quantize */
201
            s->dsp.clear_blocks(s->block[0]);
202
            
203
            s->mv_dir = MV_DIR_FORWARD;
204
            s->mv_type = MV_TYPE_16X16;
205
//            s->mb_skiped = 0;
206
//printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
207
            ret= s->decode_mb(s, s->block);
208

    
209
            if(ret<0){
210
                const int xy= s->mb_x + s->mb_y*s->mb_stride;
211
                if(ret==SLICE_END){
212
                    MPV_decode_mb(s, s->block);
213

    
214
//printf("%d %d %d %06X\n", s->mb_x, s->mb_y, s->gb.size*8 - get_bits_count(&s->gb), show_bits(&s->gb, 24));
215
                    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);
216

    
217
                    s->padding_bug_score--;
218
                        
219
                    if(++s->mb_x >= s->mb_width){
220
                        s->mb_x=0;
221
                        ff_draw_horiz_band(s, s->mb_y*16, 16);
222
                        s->mb_y++;
223
                    }
224
                    return 0; 
225
                }else if(ret==SLICE_NOEND){
226
                    fprintf(stderr,"Slice mismatch at MB: %d\n", xy);
227
                    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x+1, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);
228
                    return -1;
229
                }
230
                fprintf(stderr,"Error at MB: %d\n", xy);
231
                ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_ERROR|DC_ERROR|MV_ERROR)&part_mask);
232
    
233
                return -1;
234
            }
235

    
236
            MPV_decode_mb(s, s->block);
237
        }
238
        
239
        ff_draw_horiz_band(s, s->mb_y*16, 16);
240
        
241
        s->mb_x= 0;
242
    }
243
    
244
    assert(s->mb_x==0 && s->mb_y==s->mb_height);
245

    
246
    /* try to detect the padding bug */
247
    if(      s->codec_id==CODEC_ID_MPEG4
248
       &&   (s->workaround_bugs&FF_BUG_AUTODETECT) 
249
       &&    s->gb.size_in_bits - get_bits_count(&s->gb) >=0
250
       &&    s->gb.size_in_bits - get_bits_count(&s->gb) < 48
251
//       &&   !s->resync_marker
252
       &&   !s->data_partitioning){
253
        
254
        const int bits_count= get_bits_count(&s->gb);
255
        const int bits_left = s->gb.size_in_bits - bits_count;
256
        
257
        if(bits_left==0){
258
            s->padding_bug_score+=16;
259
        }else if(bits_left>8){
260
            s->padding_bug_score++;
261
        } else if(bits_left != 1){
262
            int v= show_bits(&s->gb, 8);
263
            v|= 0x7F >> (7-(bits_count&7));
264

    
265
            if(v==0x7F)
266
                s->padding_bug_score--;
267
            else
268
                s->padding_bug_score++;            
269
        }                          
270
    }
271

    
272
    // handle formats which dont have unique end markers
273
    if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
274
        int left= s->gb.size_in_bits - get_bits_count(&s->gb);
275
        int max_extra=7;
276
        
277
        /* no markers in M$ crap */
278
        if(s->msmpeg4_version && s->pict_type==I_TYPE)
279
            max_extra+= 17;
280
        
281
        /* buggy padding but the frame should still end approximately at the bitstream end */
282
        if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
283
            max_extra+= 48;
284
        else if((s->workaround_bugs&FF_BUG_NO_PADDING))
285
            max_extra+= 256*256*256*64;
286
        
287
        if(left>max_extra){
288
            fprintf(stderr, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
289
        }
290
        else if(left<0){
291
            fprintf(stderr, "overreading %d bits\n", -left);
292
        }else
293
            ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_END|DC_END|MV_END);
294
        
295
        return 0;
296
    }
297

    
298
    fprintf(stderr, "slice end not reached but screenspace end (%d left %06X)\n", 
299
            s->gb.size_in_bits - get_bits_count(&s->gb),
300
            show_bits(&s->gb, 24));
301
            
302
    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, (AC_END|DC_END|MV_END)&part_mask);
303

    
304
    return -1;
305
}
306

    
307
/**
308
 * finds the end of the current frame in the bitstream.
309
 * @return the position of the first byte of the next frame, or -1
310
 */
311
static int mpeg4_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
312
    ParseContext *pc= &s->parse_context;
313
    int vop_found, i;
314
    uint32_t state;
315
    
316
    vop_found= pc->frame_start_found;
317
    state= pc->state;
318
    
319
    i=0;
320
    if(!vop_found){
321
        for(i=0; i<buf_size; i++){
322
            state= (state<<8) | buf[i];
323
            if(state == 0x1B6){
324
                i++;
325
                vop_found=1;
326
                break;
327
            }
328
        }
329
    }
330

    
331
    if(vop_found){    
332
      for(; i<buf_size; i++){
333
        state= (state<<8) | buf[i];
334
        if((state&0xFFFFFF00) == 0x100){
335
            pc->frame_start_found=0;
336
            pc->state=-1; 
337
            return i-3;
338
        }
339
      }
340
    }
341
    pc->frame_start_found= vop_found;
342
    pc->state= state;
343
    return END_NOT_FOUND;
344
}
345

    
346
static int h263_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
347
    ParseContext *pc= &s->parse_context;
348
    int vop_found, i;
349
    uint32_t state;
350
    
351
    vop_found= pc->frame_start_found;
352
    state= pc->state;
353
    
354
    i=0;
355
    if(!vop_found){
356
        for(i=0; i<buf_size; i++){
357
            state= (state<<8) | buf[i];
358
            if(state>>(32-22) == 0x20){
359
                i++;
360
                vop_found=1;
361
                break;
362
            }
363
        }
364
    }
365

    
366
    if(vop_found){    
367
      for(; i<buf_size; i++){
368
        state= (state<<8) | buf[i];
369
        if(state>>(32-22) == 0x20){
370
            pc->frame_start_found=0;
371
            pc->state=-1; 
372
            return i-3;
373
        }
374
      }
375
    }
376
    pc->frame_start_found= vop_found;
377
    pc->state= state;
378
    
379
    return END_NOT_FOUND;
380
}
381

    
382
int ff_h263_decode_frame(AVCodecContext *avctx, 
383
                             void *data, int *data_size,
384
                             uint8_t *buf, int buf_size)
385
{
386
    MpegEncContext *s = avctx->priv_data;
387
    int ret,i;
388
    AVFrame *pict = data; 
389
    float new_aspect;
390
    
391
#ifdef PRINT_FRAME_TIME
392
uint64_t time= rdtsc();
393
#endif
394
#ifdef DEBUG
395
    printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
396
    printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
397
#endif
398
    s->flags= avctx->flags;
399

    
400
    *data_size = 0;
401
   
402
   /* no supplementary picture */
403
    if (buf_size == 0) {
404
        return 0;
405
    }
406

    
407
    if(s->flags&CODEC_FLAG_TRUNCATED){
408
        int next;
409
        
410
        if(s->codec_id==CODEC_ID_MPEG4){
411
            next= mpeg4_find_frame_end(s, buf, buf_size);
412
        }else if(s->codec_id==CODEC_ID_H263){
413
            next= h263_find_frame_end(s, buf, buf_size);
414
        }else{
415
            fprintf(stderr, "this codec doesnt support truncated bitstreams\n");
416
            return -1;
417
        }
418
        
419
        if( ff_combine_frame(s, next, &buf, &buf_size) < 0 )
420
            return buf_size;
421
    }
422

    
423
retry:
424
    
425
    if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
426
        init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
427
    }else
428
        init_get_bits(&s->gb, buf, buf_size*8);
429
    s->bitstream_buffer_size=0;
430

    
431
    if (!s->context_initialized) {
432
        if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
433
            return -1;
434
    }
435
      
436
    /* let's go :-) */
437
    if (s->msmpeg4_version==5) {
438
        ret= ff_wmv2_decode_picture_header(s);
439
    } else if (s->msmpeg4_version) {
440
        ret = msmpeg4_decode_picture_header(s);
441
    } else if (s->h263_pred) {
442
        if(s->avctx->extradata_size && s->picture_number==0){
443
            GetBitContext gb;
444
            
445
            init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
446
            ret = ff_mpeg4_decode_picture_header(s, &gb);
447
        }
448
        ret = ff_mpeg4_decode_picture_header(s, &s->gb);
449

    
450
        if(s->flags& CODEC_FLAG_LOW_DELAY)
451
            s->low_delay=1;
452
    } else if (s->h263_intel) {
453
        ret = intel_h263_decode_picture_header(s);
454
    } else {
455
        ret = h263_decode_picture_header(s);
456
    }
457
    avctx->has_b_frames= !s->low_delay;
458

    
459
    if(s->workaround_bugs&FF_BUG_AUTODETECT){
460
        if(s->padding_bug_score > -2 && !s->data_partitioning && !s->resync_marker)
461
            s->workaround_bugs |=  FF_BUG_NO_PADDING;
462
        else
463
            s->workaround_bugs &= ~FF_BUG_NO_PADDING;
464

    
465
        if(s->avctx->codec_tag == ff_get_fourcc("XVIX")) 
466
            s->workaround_bugs|= FF_BUG_XVID_ILACE;
467
#if 0
468
        if(s->avctx->codec_tag == ff_get_fourcc("MP4S")) 
469
            s->workaround_bugs|= FF_BUG_AC_VLC;
470
        
471
        if(s->avctx->codec_tag == ff_get_fourcc("M4S2")) 
472
            s->workaround_bugs|= FF_BUG_AC_VLC;
473
#endif
474
        if(s->avctx->codec_tag == ff_get_fourcc("UMP4")){
475
            s->workaround_bugs|= FF_BUG_UMP4;
476
            s->workaround_bugs|= FF_BUG_AC_VLC;
477
        }
478

    
479
        if(s->divx_version){
480
            s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
481
        }
482

    
483
        if(s->divx_version>502){
484
            s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
485
        }
486

    
487
        if(s->avctx->codec_tag == ff_get_fourcc("XVID") && s->xvid_build==0)
488
            s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
489
        
490
        if(s->avctx->codec_tag == ff_get_fourcc("XVID") && s->xvid_build==0)
491
            s->padding_bug_score= 256*256*256*64;
492
        
493
        if(s->xvid_build && s->xvid_build<=3)
494
            s->padding_bug_score= 256*256*256*64;
495
        
496
        if(s->xvid_build && s->xvid_build<=1)
497
            s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
498

    
499
#define SET_QPEL_FUNC(postfix1, postfix2) \
500
    s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
501
    s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
502
    s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
503

    
504
        if(s->lavc_build && s->lavc_build<4653)
505
            s->workaround_bugs|= FF_BUG_STD_QPEL;
506
        
507
        if(s->lavc_build && s->lavc_build<4655)
508
            s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
509

    
510
        if(s->divx_version)
511
            s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
512
//printf("padding_bug_score: %d\n", s->padding_bug_score);
513
        if(s->divx_version==501 && s->divx_build==20020416)
514
            s->padding_bug_score= 256*256*256*64;
515

    
516
        if(s->divx_version>=500){
517
            s->workaround_bugs|= FF_BUG_EDGE;
518
        }
519

    
520
#if 0
521
        if(s->divx_version==500)
522
            s->padding_bug_score= 256*256*256*64;
523

524
        /* very ugly XVID padding bug detection FIXME/XXX solve this differently
525
         * lets hope this at least works
526
         */
527
        if(   s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
528
           && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
529
            s->workaround_bugs|= FF_BUG_NO_PADDING;
530
        
531
        if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
532
            s->workaround_bugs|= FF_BUG_NO_PADDING;
533
#endif
534
    }
535
    
536
    if(s->workaround_bugs& FF_BUG_STD_QPEL){
537
        SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
538
        SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
539
        SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
540
        SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
541
        SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
542
        SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
543

    
544
        SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
545
        SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
546
        SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
547
        SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
548
        SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
549
        SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
550
    }
551

    
552
#if 0 // dump bits per frame / qp / complexity
553
{
554
    static FILE *f=NULL;
555
    if(!f) f=fopen("rate_qp_cplx.txt", "w");
556
    fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
557
}
558
#endif
559
       
560
        /* After H263 & mpeg4 header decode we have the height, width,*/
561
        /* and other parameters. So then we could init the picture   */
562
        /* FIXME: By the way H263 decoder is evolving it should have */
563
        /* an H263EncContext                                         */
564
    if(s->aspected_height)
565
        new_aspect= s->aspected_width*s->width / (float)(s->height*s->aspected_height);
566
    else
567
        new_aspect=0;
568
    
569
    if (   s->width != avctx->width || s->height != avctx->height 
570
        || ABS(new_aspect - avctx->aspect_ratio) > 0.001) {
571
        /* H.263 could change picture size any time */
572
        MPV_common_end(s);
573
    }
574
    if (!s->context_initialized) {
575
        avctx->width = s->width;
576
        avctx->height = s->height;
577
        avctx->aspect_ratio= new_aspect;
578

    
579
        goto retry;
580
    }
581

    
582
    if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
583
        s->gob_index = ff_h263_get_gob_height(s);
584

    
585
    if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
586
    /* skip if the header was thrashed */
587
    if (ret < 0){
588
        fprintf(stderr, "header damaged\n");
589
        return -1;
590
    }
591
    
592
    // for hurry_up==5
593
    s->current_picture.pict_type= s->pict_type;
594
    s->current_picture.key_frame= s->pict_type == I_TYPE;
595

    
596
    /* skip b frames if we dont have reference frames */
597
    if(s->last_picture_ptr==NULL && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
598
    /* skip b frames if we are in a hurry */
599
    if(avctx->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
600
    /* skip everything if we are in a hurry>=5 */
601
    if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
602
    
603
    if(s->next_p_frame_damaged){
604
        if(s->pict_type==B_TYPE)
605
            return get_consumed_bytes(s, buf_size);
606
        else
607
            s->next_p_frame_damaged=0;
608
    }
609

    
610
    if(MPV_frame_start(s, avctx) < 0)
611
        return -1;
612

    
613
#ifdef DEBUG
614
    printf("qscale=%d\n", s->qscale);
615
#endif
616

    
617
    ff_er_frame_start(s);
618
    
619
    //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
620
    //which isnt available before MPV_frame_start()
621
    if (s->msmpeg4_version==5){
622
        if(ff_wmv2_decode_secondary_picture_header(s) < 0)
623
            return -1;
624
    }
625

    
626
    /* decode each macroblock */
627
    s->mb_x=0; 
628
    s->mb_y=0;
629
    
630
    decode_slice(s);
631
    while(s->mb_y<s->mb_height){
632
        if(s->msmpeg4_version){
633
            if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_count(&s->gb) > s->gb.size_in_bits)
634
                break;
635
        }else{
636
            if(ff_h263_resync(s)<0)
637
                break;
638
        }
639
        
640
        if(s->msmpeg4_version<4 && s->h263_pred)
641
            ff_mpeg4_clean_buffers(s);
642

    
643
        decode_slice(s);
644
    }
645

    
646
    if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
647
        if(msmpeg4_decode_ext_header(s, buf_size) < 0){
648
            s->error_status_table[s->mb_num-1]= AC_ERROR|DC_ERROR|MV_ERROR;
649
        }
650
    
651
    /* divx 5.01+ bistream reorder stuff */
652
    if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_packed){
653
        int current_pos= get_bits_count(&s->gb)>>3;
654

    
655
        if(   buf_size - current_pos > 5 
656
           && buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
657
            int i;
658
            int startcode_found=0;
659
            for(i=current_pos; i<buf_size-3; i++){
660
                if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
661
                    startcode_found=1;
662
                    break;
663
                }
664
            }
665
            if(startcode_found){
666
                memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
667
                s->bitstream_buffer_size= buf_size - current_pos;
668
            }
669
        }
670
    }
671

    
672
    ff_er_frame_end(s);
673

    
674
    MPV_frame_end(s);
675

    
676
assert(s->current_picture.pict_type == s->current_picture_ptr->pict_type);
677
assert(s->current_picture.pict_type == s->pict_type);
678
    if(s->pict_type==B_TYPE || s->low_delay){
679
        *pict= *(AVFrame*)&s->current_picture;
680
        ff_print_debug_info(s, s->current_picture_ptr);
681
    } else {
682
        *pict= *(AVFrame*)&s->last_picture;
683
        ff_print_debug_info(s, s->last_picture_ptr);
684
    }
685

    
686
    /* Return the Picture timestamp as the frame number */
687
    /* we substract 1 because it is added on utils.c    */
688
    avctx->frame_number = s->picture_number - 1;
689

    
690
    /* dont output the last pic after seeking */
691
    if(s->last_picture_ptr || s->low_delay)
692
        *data_size = sizeof(AVFrame);
693
#ifdef PRINT_FRAME_TIME
694
printf("%Ld\n", rdtsc()-time);
695
#endif
696

    
697
    return get_consumed_bytes(s, buf_size);
698
}
699

    
700
static const AVOption mpeg4_decoptions[] =
701
{
702
    AVOPTION_SUB(avoptions_workaround_bug),
703
    AVOPTION_END()
704
};
705

    
706
AVCodec mpeg4_decoder = {
707
    "mpeg4",
708
    CODEC_TYPE_VIDEO,
709
    CODEC_ID_MPEG4,
710
    sizeof(MpegEncContext),
711
    ff_h263_decode_init,
712
    NULL,
713
    ff_h263_decode_end,
714
    ff_h263_decode_frame,
715
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
716
    .options = mpeg4_decoptions,
717
};
718

    
719
AVCodec h263_decoder = {
720
    "h263",
721
    CODEC_TYPE_VIDEO,
722
    CODEC_ID_H263,
723
    sizeof(MpegEncContext),
724
    ff_h263_decode_init,
725
    NULL,
726
    ff_h263_decode_end,
727
    ff_h263_decode_frame,
728
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
729
};
730

    
731
AVCodec msmpeg4v1_decoder = {
732
    "msmpeg4v1",
733
    CODEC_TYPE_VIDEO,
734
    CODEC_ID_MSMPEG4V1,
735
    sizeof(MpegEncContext),
736
    ff_h263_decode_init,
737
    NULL,
738
    ff_h263_decode_end,
739
    ff_h263_decode_frame,
740
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
741
    mpeg4_decoptions,
742
};
743

    
744
AVCodec msmpeg4v2_decoder = {
745
    "msmpeg4v2",
746
    CODEC_TYPE_VIDEO,
747
    CODEC_ID_MSMPEG4V2,
748
    sizeof(MpegEncContext),
749
    ff_h263_decode_init,
750
    NULL,
751
    ff_h263_decode_end,
752
    ff_h263_decode_frame,
753
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
754
    mpeg4_decoptions,
755
};
756

    
757
AVCodec msmpeg4v3_decoder = {
758
    "msmpeg4",
759
    CODEC_TYPE_VIDEO,
760
    CODEC_ID_MSMPEG4V3,
761
    sizeof(MpegEncContext),
762
    ff_h263_decode_init,
763
    NULL,
764
    ff_h263_decode_end,
765
    ff_h263_decode_frame,
766
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
767
    .options = mpeg4_decoptions,
768
};
769

    
770
AVCodec wmv1_decoder = {
771
    "wmv1",
772
    CODEC_TYPE_VIDEO,
773
    CODEC_ID_WMV1,
774
    sizeof(MpegEncContext),
775
    ff_h263_decode_init,
776
    NULL,
777
    ff_h263_decode_end,
778
    ff_h263_decode_frame,
779
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
780
    mpeg4_decoptions,
781
};
782

    
783
AVCodec h263i_decoder = {
784
    "h263i",
785
    CODEC_TYPE_VIDEO,
786
    CODEC_ID_H263I,
787
    sizeof(MpegEncContext),
788
    ff_h263_decode_init,
789
    NULL,
790
    ff_h263_decode_end,
791
    ff_h263_decode_frame,
792
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
793
    mpeg4_decoptions,
794
};
795