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1
/*
2
 * MPEG1 encoder / MPEG2 decoder
3
 * Copyright (c) 2000,2001 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
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18
 */
19
//#define DEBUG
20
#include "avcodec.h"
21
#include "dsputil.h"
22
#include "mpegvideo.h"
23

    
24
#include "mpeg12data.h"
25

    
26
#if 1
27
#define PRINT_QP(a, b) {}
28
#else
29
#define PRINT_QP(a, b) printf(a, b)
30
#endif
31

    
32
/* Start codes. */
33
#define SEQ_END_CODE                0x000001b7
34
#define SEQ_START_CODE                0x000001b3
35
#define GOP_START_CODE                0x000001b8
36
#define PICTURE_START_CODE        0x00000100
37
#define SLICE_MIN_START_CODE        0x00000101
38
#define SLICE_MAX_START_CODE        0x000001af
39
#define EXT_START_CODE                0x000001b5
40
#define USER_START_CODE                0x000001b2
41

    
42
#define DC_VLC_BITS 9
43
#define MV_VLC_BITS 9
44
#define MBINCR_VLC_BITS 9
45
#define MB_PAT_VLC_BITS 9
46
#define MB_PTYPE_VLC_BITS 6
47
#define MB_BTYPE_VLC_BITS 6
48
#define TEX_VLC_BITS 9
49

    
50
static void mpeg1_encode_block(MpegEncContext *s, 
51
                         DCTELEM *block, 
52
                         int component);
53
static void mpeg1_encode_motion(MpegEncContext *s, int val);
54
static void mpeg1_skip_picture(MpegEncContext *s, int pict_num);
55
static inline int mpeg1_decode_block_inter(MpegEncContext *s, 
56
                              DCTELEM *block, 
57
                              int n);
58
static inline int mpeg1_decode_block_intra(MpegEncContext *s, 
59
                              DCTELEM *block, 
60
                              int n);
61
static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, 
62
                                        DCTELEM *block, 
63
                                        int n);
64
static inline int mpeg2_decode_block_intra(MpegEncContext *s, 
65
                                    DCTELEM *block, 
66
                                    int n);
67
static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
68

    
69
static UINT16 mv_penalty[MAX_FCODE+1][MAX_MV*2+1];
70
static UINT8 fcode_tab[MAX_MV*2+1];
71

    
72
static void init_2d_vlc_rl(RLTable *rl)
73
{
74
    int i;
75
    
76
    init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2, 
77
             &rl->table_vlc[0][1], 4, 2,
78
             &rl->table_vlc[0][0], 4, 2);
79

    
80
    
81
    rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
82
    for(i=0; i<rl->vlc.table_size; i++){
83
        int code= rl->vlc.table[i][0];
84
        int len = rl->vlc.table[i][1];
85
        int level, run;
86
    
87
        if(len==0){ // illegal code
88
            run= 65;
89
            level= MAX_LEVEL;
90
        }else if(len<0){ //more bits needed
91
            run= 0;
92
            level= code;
93
        }else{
94
            if(code==rl->n){ //esc
95
                run= 65;
96
                level= 0;
97
            }else if(code==rl->n+1){ //eob
98
                run= 0;
99
                level= 127;
100
            }else{
101
                run=   rl->table_run  [code] + 1;
102
                level= rl->table_level[code];
103
            }
104
        }
105
        rl->rl_vlc[0][i].len= len;
106
        rl->rl_vlc[0][i].level= level;
107
        rl->rl_vlc[0][i].run= run;
108
    }
109
}
110

    
111

    
112
static void put_header(MpegEncContext *s, int header)
113
{
114
    align_put_bits(&s->pb);
115
    put_bits(&s->pb, 16, header>>16);
116
    put_bits(&s->pb, 16, header&0xFFFF);
117
}
118

    
119
/* put sequence header if needed */
120
static void mpeg1_encode_sequence_header(MpegEncContext *s)
121
{
122
        unsigned int vbv_buffer_size;
123
        unsigned int fps, v;
124
        int n;
125
        UINT64 time_code;
126
        
127
        if (s->picture_in_gop_number == 0) {
128
            /* mpeg1 header repeated every gop */
129
            put_header(s, SEQ_START_CODE);
130
            
131
            /* search closest frame rate */
132
            {
133
                int i, dmin, d;
134
                s->frame_rate_index = 0;
135
                dmin = 0x7fffffff;
136
                for(i=1;i<9;i++) {
137
                    d = abs(s->frame_rate - frame_rate_tab[i]);
138
                    if (d < dmin) {
139
                        dmin = d;
140
                        s->frame_rate_index = i;
141
                    }
142
                }
143
            }
144
 
145
            put_bits(&s->pb, 12, s->width);
146
            put_bits(&s->pb, 12, s->height);
147
            put_bits(&s->pb, 4, 1); /* 1/1 aspect ratio */
148
            put_bits(&s->pb, 4, s->frame_rate_index);
149
            v = s->bit_rate / 400;
150
            if (v > 0x3ffff)
151
                v = 0x3ffff;
152
            put_bits(&s->pb, 18, v);
153
            put_bits(&s->pb, 1, 1); /* marker */
154

    
155
            if(s->avctx->rc_buffer_size)
156
                vbv_buffer_size = s->avctx->rc_buffer_size;
157
            else
158
                /* VBV calculation: Scaled so that a VCD has the proper VBV size of 40 kilobytes */
159
                vbv_buffer_size = (( 20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024;         
160
            put_bits(&s->pb, 10, (vbv_buffer_size + 16383) / 16384); 
161
            put_bits(&s->pb, 1, 1); /* constrained parameter flag */
162
            put_bits(&s->pb, 1, 0); /* no custom intra matrix */
163
            put_bits(&s->pb, 1, 0); /* no custom non intra matrix */
164

    
165
            put_header(s, GOP_START_CODE);
166
            put_bits(&s->pb, 1, 0); /* do drop frame */
167
            /* time code : we must convert from the real frame rate to a
168
               fake mpeg frame rate in case of low frame rate */
169
            fps = frame_rate_tab[s->frame_rate_index];
170
            time_code = (INT64)s->fake_picture_number * FRAME_RATE_BASE;
171
            s->gop_picture_number = s->fake_picture_number;
172
            put_bits(&s->pb, 5, (UINT32)((time_code / (fps * 3600)) % 24));
173
            put_bits(&s->pb, 6, (UINT32)((time_code / (fps * 60)) % 60));
174
            put_bits(&s->pb, 1, 1);
175
            put_bits(&s->pb, 6, (UINT32)((time_code / fps) % 60));
176
            put_bits(&s->pb, 6, (UINT32)((time_code % fps) / FRAME_RATE_BASE));
177
            put_bits(&s->pb, 1, 1); /* closed gop */
178
            put_bits(&s->pb, 1, 0); /* broken link */
179
        }
180

    
181
        if (s->frame_rate < (24 * FRAME_RATE_BASE) && s->picture_number > 0) {
182
            /* insert empty P pictures to slow down to the desired
183
               frame rate. Each fake pictures takes about 20 bytes */
184
            fps = frame_rate_tab[s->frame_rate_index];
185
            n = (((INT64)s->picture_number * fps) / s->frame_rate) - 1;
186
            while (s->fake_picture_number < n) {
187
                mpeg1_skip_picture(s, s->fake_picture_number - 
188
                                   s->gop_picture_number); 
189
                s->fake_picture_number++;
190
            }
191

    
192
        }
193
}
194

    
195

    
196
/* insert a fake P picture */
197
static void mpeg1_skip_picture(MpegEncContext *s, int pict_num)
198
{
199
    unsigned int mb_incr;
200

    
201
    /* mpeg1 picture header */
202
    put_header(s, PICTURE_START_CODE);
203
    /* temporal reference */
204
    put_bits(&s->pb, 10, pict_num & 0x3ff); 
205
    
206
    put_bits(&s->pb, 3, P_TYPE);
207
    put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
208
    
209
    put_bits(&s->pb, 1, 1); /* integer coordinates */
210
    put_bits(&s->pb, 3, 1); /* forward_f_code */
211
    
212
    put_bits(&s->pb, 1, 0); /* extra bit picture */
213
    
214
    /* only one slice */
215
    put_header(s, SLICE_MIN_START_CODE);
216
    put_bits(&s->pb, 5, 1); /* quantizer scale */
217
    put_bits(&s->pb, 1, 0); /* slice extra information */
218
    
219
    mb_incr = 1;
220
    put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1], 
221
             mbAddrIncrTable[mb_incr - 1][0]);
222
    
223
    /* empty macroblock */
224
    put_bits(&s->pb, 3, 1); /* motion only */
225
    
226
    /* zero motion x & y */
227
    put_bits(&s->pb, 1, 1); 
228
    put_bits(&s->pb, 1, 1); 
229

    
230
    /* output a number of empty slice */
231
    mb_incr = s->mb_width * s->mb_height - 1;
232
    while (mb_incr > 33) {
233
        put_bits(&s->pb, 11, 0x008);
234
        mb_incr -= 33;
235
    }
236
    put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1], 
237
             mbAddrIncrTable[mb_incr - 1][0]);
238
    
239
    /* empty macroblock */
240
    put_bits(&s->pb, 3, 1); /* motion only */
241
    
242
    /* zero motion x & y */
243
    put_bits(&s->pb, 1, 1); 
244
    put_bits(&s->pb, 1, 1); 
245
}
246

    
247
static void common_init(MpegEncContext *s)
248
{
249
    s->y_dc_scale_table=
250
    s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
251
}
252

    
253
void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
254
{
255
    mpeg1_encode_sequence_header(s);
256

    
257
    /* mpeg1 picture header */
258
    put_header(s, PICTURE_START_CODE);
259
    /* temporal reference */
260
    put_bits(&s->pb, 10, (s->fake_picture_number - 
261
                          s->gop_picture_number) & 0x3ff); 
262
    s->fake_picture_number++;
263
    
264
    put_bits(&s->pb, 3, s->pict_type);
265
    put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
266
    
267
    if (s->pict_type == P_TYPE) {
268
        put_bits(&s->pb, 1, 0); /* half pel coordinates */
269
        put_bits(&s->pb, 3, s->f_code); /* forward_f_code */
270
    }
271
    
272
    put_bits(&s->pb, 1, 0); /* extra bit picture */
273
    
274
    /* only one slice */
275
    put_header(s, SLICE_MIN_START_CODE);
276
    put_bits(&s->pb, 5, s->qscale); /* quantizer scale */
277
    put_bits(&s->pb, 1, 0); /* slice extra information */
278
}
279

    
280
void mpeg1_encode_mb(MpegEncContext *s,
281
                     DCTELEM block[6][64],
282
                     int motion_x, int motion_y)
283
{
284
    int mb_incr, i, cbp, mb_x, mb_y;
285

    
286
    mb_x = s->mb_x;
287
    mb_y = s->mb_y;
288

    
289
    /* compute cbp */
290
    cbp = 0;
291
    for(i=0;i<6;i++) {
292
        if (s->block_last_index[i] >= 0)
293
            cbp |= 1 << (5 - i);
294
    }
295

    
296
    /* skip macroblock, except if first or last macroblock of a slice */
297
    if ((cbp | motion_x | motion_y) == 0 &&
298
        (!((mb_x | mb_y) == 0 ||
299
           (mb_x == s->mb_width - 1 && mb_y == s->mb_height - 1)))) {
300
        s->mb_incr++;
301
        s->qscale -= s->dquant;
302
    } else {
303
        /* output mb incr */
304
        mb_incr = s->mb_incr;
305

    
306
        while (mb_incr > 33) {
307
            put_bits(&s->pb, 11, 0x008);
308
            mb_incr -= 33;
309
        }
310
        put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1], 
311
                 mbAddrIncrTable[mb_incr - 1][0]);
312
        
313
        if (s->pict_type == I_TYPE) {
314
            if(s->dquant && cbp){
315
                put_bits(&s->pb, 2, 1); /* macroblock_type : macroblock_quant = 1 */
316
                put_bits(&s->pb, 5, s->qscale);
317
            }else{
318
                put_bits(&s->pb, 1, 1); /* macroblock_type : macroblock_quant = 0 */
319
                s->qscale -= s->dquant;
320
            }
321
        } else {
322
            if (s->mb_intra) {
323
                if(s->dquant && cbp){
324
                    put_bits(&s->pb, 6, 0x01);
325
                    put_bits(&s->pb, 5, s->qscale);
326
                }else{
327
                    put_bits(&s->pb, 5, 0x03);
328
                    s->qscale -= s->dquant;
329
                }
330
            } else {
331
                if (cbp != 0) {
332
                    if (motion_x == 0 && motion_y == 0) {
333
                        if(s->dquant){
334
                            put_bits(&s->pb, 5, 1); /* macroblock_pattern & quant */
335
                            put_bits(&s->pb, 5, s->qscale);
336
                        }else{
337
                            put_bits(&s->pb, 2, 1); /* macroblock_pattern only */
338
                        }
339
                        put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
340
                    } else {
341
                        if(s->dquant){
342
                            put_bits(&s->pb, 5, 2); /* motion + cbp */
343
                            put_bits(&s->pb, 5, s->qscale);
344
                        }else{
345
                            put_bits(&s->pb, 1, 1); /* motion + cbp */
346
                        }
347
                        mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0]); 
348
                        mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1]); 
349
                        put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
350
                    }
351
                } else {
352
                    put_bits(&s->pb, 3, 1); /* motion only */
353
                    mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0]); 
354
                    mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1]); 
355
                    s->qscale -= s->dquant;
356
                }
357
            }
358
        }
359
        for(i=0;i<6;i++) {
360
            if (cbp & (1 << (5 - i))) {
361
                mpeg1_encode_block(s, block[i], i);
362
            }
363
        }
364
        s->mb_incr = 1;
365
    }
366
    s->last_mv[0][0][0] = motion_x;
367
    s->last_mv[0][0][1] = motion_y;
368
}
369

    
370
static void mpeg1_encode_motion(MpegEncContext *s, int val)
371
{
372
    int code, bit_size, l, m, bits, range, sign;
373

    
374
    if (val == 0) {
375
        /* zero vector */
376
        code = 0;
377
        put_bits(&s->pb,
378
                 mbMotionVectorTable[0][1], 
379
                 mbMotionVectorTable[0][0]); 
380
    } else {
381
        bit_size = s->f_code - 1;
382
        range = 1 << bit_size;
383
        /* modulo encoding */
384
        l = 16 * range;
385
        m = 2 * l;
386
        if (val < -l) {
387
            val += m;
388
        } else if (val >= l) {
389
            val -= m;
390
        }
391

    
392
        if (val >= 0) {
393
            val--;
394
            code = (val >> bit_size) + 1;
395
            bits = val & (range - 1);
396
            sign = 0;
397
        } else {
398
            val = -val;
399
            val--;
400
            code = (val >> bit_size) + 1;
401
            bits = val & (range - 1);
402
            sign = 1;
403
        }
404
        put_bits(&s->pb,
405
                 mbMotionVectorTable[code][1], 
406
                 mbMotionVectorTable[code][0]); 
407
        put_bits(&s->pb, 1, sign);
408
        if (bit_size > 0) {
409
            put_bits(&s->pb, bit_size, bits);
410
        }
411
    }
412
}
413

    
414
void ff_mpeg1_encode_init(MpegEncContext *s)
415
{
416
    static int done=0;
417

    
418
    common_init(s);
419

    
420
    if(!done){
421
        int f_code;
422
        int mv;
423
        int i;
424

    
425
        done=1;
426
        init_rl(&rl_mpeg1);
427
        
428
        for(i=0; i<64; i++)
429
        {
430
                mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i];
431
                mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i];
432
        }
433

    
434
        /* build unified dc encoding tables */
435
        for(i=-255; i<256; i++)
436
        {
437
                int adiff, index;
438
                int bits, code;
439
                int diff=i;
440

    
441
                adiff = ABS(diff);
442
                if(diff<0) diff--;
443
                index = vlc_dc_table[adiff];
444

    
445
                bits= vlc_dc_lum_bits[index] + index;
446
                code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1));
447
                mpeg1_lum_dc_uni[i+255]= bits + (code<<8);
448
                
449
                bits= vlc_dc_chroma_bits[index] + index;
450
                code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1));
451
                mpeg1_chr_dc_uni[i+255]= bits + (code<<8);
452
        }
453

    
454
        for(f_code=1; f_code<=MAX_FCODE; f_code++){
455
            for(mv=-MAX_MV; mv<=MAX_MV; mv++){
456
                int len;
457

    
458
                if(mv==0) len= mbMotionVectorTable[0][1];
459
                else{
460
                    int val, bit_size, range, code;
461

    
462
                    bit_size = s->f_code - 1;
463
                    range = 1 << bit_size;
464

    
465
                    val=mv;
466
                    if (val < 0) 
467
                        val = -val;
468
                    val--;
469
                    code = (val >> bit_size) + 1;
470
                    if(code<17){
471
                        len= mbMotionVectorTable[code][1] + 1 + bit_size;
472
                    }else{
473
                        len= mbMotionVectorTable[16][1] + 2 + bit_size;
474
                    }
475
                }
476

    
477
                mv_penalty[f_code][mv+MAX_MV]= len;
478
            }
479
        }
480
        
481

    
482
        for(f_code=MAX_FCODE; f_code>0; f_code--){
483
            for(mv=-(8<<f_code); mv<(8<<f_code); mv++){
484
                fcode_tab[mv+MAX_MV]= f_code;
485
            }
486
        }
487
    }
488
    s->mv_penalty= mv_penalty;
489
    s->fcode_tab= fcode_tab;
490
    s->min_qcoeff=-255;
491
    s->max_qcoeff= 255;
492
    s->intra_quant_bias= 3<<(QUANT_BIAS_SHIFT-3); //(a + x*3/8)/x
493
    s->inter_quant_bias= 0;
494
}
495

    
496
static inline void encode_dc(MpegEncContext *s, int diff, int component)
497
{
498
    if (component == 0) {
499
        put_bits(
500
            &s->pb, 
501
            mpeg1_lum_dc_uni[diff+255]&0xFF,
502
            mpeg1_lum_dc_uni[diff+255]>>8);
503
    } else {
504
        put_bits(
505
            &s->pb, 
506
            mpeg1_chr_dc_uni[diff+255]&0xFF,
507
            mpeg1_chr_dc_uni[diff+255]>>8);
508
    }
509
}
510

    
511
static void mpeg1_encode_block(MpegEncContext *s, 
512
                               DCTELEM *block, 
513
                               int n)
514
{
515
    int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign;
516
    int code, component;
517
//    RLTable *rl = &rl_mpeg1;
518

    
519
    last_index = s->block_last_index[n];
520

    
521
    /* DC coef */
522
    if (s->mb_intra) {
523
        component = (n <= 3 ? 0 : n - 4 + 1);
524
        dc = block[0]; /* overflow is impossible */
525
        diff = dc - s->last_dc[component];
526
        encode_dc(s, diff, component);
527
        s->last_dc[component] = dc;
528
        i = 1;
529
    } else {
530
        /* encode the first coefficient : needs to be done here because
531
           it is handled slightly differently */
532
        level = block[0];
533
        if (abs(level) == 1) {
534
                code = ((UINT32)level >> 31); /* the sign bit */
535
                put_bits(&s->pb, 2, code | 0x02);
536
                i = 1;
537
        } else {
538
            i = 0;
539
            last_non_zero = -1;
540
            goto next_coef;
541
        }
542
    }
543

    
544
    /* now quantify & encode AC coefs */
545
    last_non_zero = i - 1;
546

    
547
    for(;i<=last_index;i++) {
548
        j = s->intra_scantable.permutated[i];
549
        level = block[j];
550
    next_coef:
551
#if 0
552
        if (level != 0)
553
            dprintf("level[%d]=%d\n", i, level);
554
#endif            
555
        /* encode using VLC */
556
        if (level != 0) {
557
            run = i - last_non_zero - 1;
558
            
559
            alevel= level;
560
            MASK_ABS(sign, alevel)
561
            sign&=1;
562

    
563
//            code = get_rl_index(rl, 0, run, alevel);
564
            if (alevel > mpeg1_max_level[0][run])
565
                code= 111; /*rl->n*/
566
            else
567
                code= mpeg1_index_run[0][run] + alevel - 1;
568

    
569
            if (code < 111 /* rl->n */) {
570
                    /* store the vlc & sign at once */
571
                put_bits(&s->pb, mpeg1_vlc[code][1]+1, (mpeg1_vlc[code][0]<<1) + sign);
572
            } else {
573
                /* escape seems to be pretty rare <5% so i dont optimize it */
574
                put_bits(&s->pb, mpeg1_vlc[111/*rl->n*/][1], mpeg1_vlc[111/*rl->n*/][0]);
575
                /* escape: only clip in this case */
576
                put_bits(&s->pb, 6, run);
577
                if (alevel < 128) {
578
                    put_bits(&s->pb, 8, level & 0xff);
579
                } else {
580
                    if (level < 0) {
581
                        put_bits(&s->pb, 16, 0x8001 + level + 255);
582
                    } else {
583
                        put_bits(&s->pb, 16, level & 0xffff);
584
                    }
585
                }
586
            }
587
            last_non_zero = i;
588
        }
589
    }
590
    /* end of block */
591
    put_bits(&s->pb, 2, 0x2);
592
}
593

    
594
/******************************************/
595
/* decoding */
596

    
597
static VLC dc_lum_vlc;
598
static VLC dc_chroma_vlc;
599
static VLC mv_vlc;
600
static VLC mbincr_vlc;
601
static VLC mb_ptype_vlc;
602
static VLC mb_btype_vlc;
603
static VLC mb_pat_vlc;
604

    
605
static void init_vlcs(MpegEncContext *s)
606
{
607
    static int done = 0;
608

    
609
    if (!done) {
610
        done = 1;
611

    
612
        init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12, 
613
                 vlc_dc_lum_bits, 1, 1,
614
                 vlc_dc_lum_code, 2, 2);
615
        init_vlc(&dc_chroma_vlc,  DC_VLC_BITS, 12, 
616
                 vlc_dc_chroma_bits, 1, 1,
617
                 vlc_dc_chroma_code, 2, 2);
618
        init_vlc(&mv_vlc, MV_VLC_BITS, 17, 
619
                 &mbMotionVectorTable[0][1], 2, 1,
620
                 &mbMotionVectorTable[0][0], 2, 1);
621
        init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 35, 
622
                 &mbAddrIncrTable[0][1], 2, 1,
623
                 &mbAddrIncrTable[0][0], 2, 1);
624
        init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 63, 
625
                 &mbPatTable[0][1], 2, 1,
626
                 &mbPatTable[0][0], 2, 1);
627
        
628
        init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 32, 
629
                 &table_mb_ptype[0][1], 2, 1,
630
                 &table_mb_ptype[0][0], 2, 1);
631
        init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 32, 
632
                 &table_mb_btype[0][1], 2, 1,
633
                 &table_mb_btype[0][0], 2, 1);
634
        init_rl(&rl_mpeg1);
635
        init_rl(&rl_mpeg2);
636

    
637
        init_2d_vlc_rl(&rl_mpeg1);
638
        init_2d_vlc_rl(&rl_mpeg2);
639
    }
640
}
641

    
642
static inline int get_dmv(MpegEncContext *s)
643
{
644
    if(get_bits1(&s->gb)) 
645
        return 1 - (get_bits1(&s->gb) << 1);
646
    else
647
        return 0;
648
}
649

    
650
static inline int get_qscale(MpegEncContext *s)
651
{
652
    int qscale;
653
    if (s->mpeg2) {
654
        if (s->q_scale_type) {
655
            qscale = non_linear_qscale[get_bits(&s->gb, 5)];
656
        } else {
657
            qscale = get_bits(&s->gb, 5) << 1;
658
        }
659
    } else {
660
        /* for mpeg1, we use the generic unquant code */
661
        qscale = get_bits(&s->gb, 5);
662
    }
663
    return qscale;
664
}
665

    
666
/* motion type (for mpeg2) */
667
#define MT_FIELD 1
668
#define MT_FRAME 2
669
#define MT_16X8  2
670
#define MT_DMV   3
671

    
672
static int mpeg_decode_mb(MpegEncContext *s,
673
                          DCTELEM block[6][64])
674
{
675
    int i, j, k, cbp, val, code, mb_type, motion_type;
676
    
677
    dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
678

    
679
    if (--s->mb_incr != 0) {
680
        /* skip mb */
681
        s->mb_intra = 0;
682
        for(i=0;i<6;i++)
683
            s->block_last_index[i] = -1;
684
        s->mv_type = MV_TYPE_16X16;
685
        if (s->pict_type == P_TYPE) {
686
            /* if P type, zero motion vector is implied */
687
            s->mv_dir = MV_DIR_FORWARD;
688
            s->mv[0][0][0] = s->mv[0][0][1] = 0;
689
            s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
690
            s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
691
        } else {
692
            /* if B type, reuse previous vectors and directions */
693
            s->mv[0][0][0] = s->last_mv[0][0][0];
694
            s->mv[0][0][1] = s->last_mv[0][0][1];
695
            s->mv[1][0][0] = s->last_mv[1][0][0];
696
            s->mv[1][0][1] = s->last_mv[1][0][1];
697
        }
698
        s->mb_skiped = 1;
699
        return 0;
700
    }
701

    
702
    switch(s->pict_type) {
703
    default:
704
    case I_TYPE:
705
        if (get_bits1(&s->gb) == 0) {
706
            if (get_bits1(&s->gb) == 0)
707
                return -1;
708
            mb_type = MB_QUANT | MB_INTRA;
709
        } else {
710
            mb_type = MB_INTRA;
711
        }
712
        break;
713
    case P_TYPE:
714
        mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
715
        if (mb_type < 0){
716
            fprintf(stderr, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
717
            return -1;
718
        }
719
        break;
720
    case B_TYPE:
721
        mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
722
        if (mb_type < 0){
723
            fprintf(stderr, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
724
            return -1;
725
        }
726
        break;
727
    }
728
    dprintf("mb_type=%x\n", mb_type);
729
    motion_type = 0; /* avoid warning */
730
    if (mb_type & (MB_FOR|MB_BACK)) {
731
        /* get additionnal motion vector type */
732
        if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) 
733
            motion_type = MT_FRAME;
734
        else
735
            motion_type = get_bits(&s->gb, 2);
736
    }
737
    /* compute dct type */
738
    if (s->picture_structure == PICT_FRAME && 
739
        !s->frame_pred_frame_dct &&
740
        (mb_type & (MB_PAT | MB_INTRA))) {
741
        s->interlaced_dct = get_bits1(&s->gb);
742
#ifdef DEBUG
743
        if (s->interlaced_dct)
744
            printf("interlaced_dct\n");
745
#endif
746
    } else {
747
        s->interlaced_dct = 0; /* frame based */
748
    }
749

    
750
    if (mb_type & MB_QUANT) {
751
        s->qscale = get_qscale(s);
752
    }
753
    if (mb_type & MB_INTRA) {
754
        if (s->concealment_motion_vectors) {
755
            /* just parse them */
756
            if (s->picture_structure != PICT_FRAME) 
757
                skip_bits1(&s->gb); /* field select */
758
            mpeg_decode_motion(s, s->mpeg_f_code[0][0], 0);
759
            mpeg_decode_motion(s, s->mpeg_f_code[0][1], 0);
760
        }
761
        s->mb_intra = 1;
762
        cbp = 0x3f;
763
        memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
764
    } else {
765
        s->mb_intra = 0;
766
        cbp = 0;
767
    }
768
    /* special case of implicit zero motion vector */
769
    if (s->pict_type == P_TYPE && !(mb_type & MB_FOR)) {
770
        s->mv_dir = MV_DIR_FORWARD;
771
        s->mv_type = MV_TYPE_16X16;
772
        s->last_mv[0][0][0] = 0;
773
        s->last_mv[0][0][1] = 0;
774
        s->last_mv[0][1][0] = 0;
775
        s->last_mv[0][1][1] = 0;
776
        s->mv[0][0][0] = 0;
777
        s->mv[0][0][1] = 0;
778
    } else if (mb_type & (MB_FOR | MB_BACK)) {
779
        /* motion vectors */
780
        s->mv_dir = 0;
781
        for(i=0;i<2;i++) {
782
            if (mb_type & (MB_FOR >> i)) {
783
                s->mv_dir |= (MV_DIR_FORWARD >> i);
784
                dprintf("motion_type=%d\n", motion_type);
785
                switch(motion_type) {
786
                case MT_FRAME: /* or MT_16X8 */
787
                    if (s->picture_structure == PICT_FRAME) {
788
                        /* MT_FRAME */
789
                        s->mv_type = MV_TYPE_16X16;
790
                        for(k=0;k<2;k++) {
791
                            val = mpeg_decode_motion(s, s->mpeg_f_code[i][k], 
792
                                                     s->last_mv[i][0][k]);
793
                            s->last_mv[i][0][k] = val;
794
                            s->last_mv[i][1][k] = val;
795
                            /* full_pel: only for mpeg1 */
796
                            if (s->full_pel[i])
797
                                val = val << 1;
798
                            s->mv[i][0][k] = val;
799
                            dprintf("mv%d: %d\n", k, val);
800
                        }
801
                    } else {
802
                        /* MT_16X8 */
803
                        s->mv_type = MV_TYPE_16X8;
804
                        for(j=0;j<2;j++) {
805
                            s->field_select[i][j] = get_bits1(&s->gb);
806
                            for(k=0;k<2;k++) {
807
                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
808
                                                         s->last_mv[i][j][k]);
809
                                s->last_mv[i][j][k] = val;
810
                                s->mv[i][j][k] = val;
811
                            }
812
                        }
813
                    }
814
                    break;
815
                case MT_FIELD:
816
                    if (s->picture_structure == PICT_FRAME) {
817
                        s->mv_type = MV_TYPE_FIELD;
818
                        for(j=0;j<2;j++) {
819
                            s->field_select[i][j] = get_bits1(&s->gb);
820
                            val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
821
                                                     s->last_mv[i][j][0]);
822
                            s->last_mv[i][j][0] = val;
823
                            s->mv[i][j][0] = val;
824
                            dprintf("fmx=%d\n", val);
825
                            val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
826
                                                     s->last_mv[i][j][1] >> 1);
827
                            s->last_mv[i][j][1] = val << 1;
828
                            s->mv[i][j][1] = val;
829
                            dprintf("fmy=%d\n", val);
830
                        }
831
                    } else {
832
                        s->mv_type = MV_TYPE_16X16;
833
                        s->field_select[i][0] = get_bits1(&s->gb);
834
                        for(k=0;k<2;k++) {
835
                            val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
836
                                                     s->last_mv[i][0][k]);
837
                            s->last_mv[i][0][k] = val;
838
                            s->last_mv[i][1][k] = val;
839
                            s->mv[i][0][k] = val;
840
                        }
841
                    }
842
                    break;
843
                case MT_DMV:
844
                    {
845
                        int dmx, dmy, mx, my, m;
846

    
847
                        mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0], 
848
                                                s->last_mv[i][0][0]);
849
                        s->last_mv[i][0][0] = mx;
850
                        s->last_mv[i][1][0] = mx;
851
                        dmx = get_dmv(s);
852
                        my = mpeg_decode_motion(s, s->mpeg_f_code[i][1], 
853
                                                s->last_mv[i][0][1] >> 1);
854
                        dmy = get_dmv(s);
855
                        s->mv_type = MV_TYPE_DMV;
856
                        /* XXX: totally broken */
857
                        if (s->picture_structure == PICT_FRAME) {
858
                            s->last_mv[i][0][1] = my << 1;
859
                            s->last_mv[i][1][1] = my << 1;
860

    
861
                            m = s->top_field_first ? 1 : 3;
862
                            /* top -> top pred */
863
                            s->mv[i][0][0] = mx; 
864
                            s->mv[i][0][1] = my << 1;
865
                            s->mv[i][1][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
866
                            s->mv[i][1][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
867
                            m = 4 - m;
868
                            s->mv[i][2][0] = mx;
869
                            s->mv[i][2][1] = my << 1;
870
                            s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
871
                            s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
872
                        } else {
873
                            s->last_mv[i][0][1] = my;
874
                            s->last_mv[i][1][1] = my;
875
                            s->mv[i][0][0] = mx;
876
                            s->mv[i][0][1] = my;
877
                            s->mv[i][1][0] = ((mx + (mx > 0)) >> 1) + dmx;
878
                            s->mv[i][1][1] = ((my + (my > 0)) >> 1) + dmy - 1 
879
                                /* + 2 * cur_field */;
880
                        }
881
                    }
882
                    break;
883
                }
884
            }
885
        }
886
    }
887

    
888
    if ((mb_type & MB_INTRA) && s->concealment_motion_vectors) {
889
        skip_bits1(&s->gb); /* marker */
890
    }
891
    
892
    if (mb_type & MB_PAT) {
893
        cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
894
        if (cbp < 0){
895
            fprintf(stderr, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
896
            return -1;
897
        }
898
        cbp++;
899
    }
900
    dprintf("cbp=%x\n", cbp);
901

    
902
    if (s->mpeg2) {
903
        if (s->mb_intra) {
904
            for(i=0;i<6;i++) {
905
                if (mpeg2_decode_block_intra(s, block[i], i) < 0)
906
                    return -1;
907
            }
908
        } else {
909
            for(i=0;i<6;i++) {
910
                if (cbp & 32) {
911
                    if (mpeg2_decode_block_non_intra(s, block[i], i) < 0)
912
                        return -1;
913
                } else {
914
                    s->block_last_index[i] = -1;
915
                }
916
                cbp+=cbp;
917
            }
918
        }
919
    } else {
920
        if (s->mb_intra) {
921
            for(i=0;i<6;i++) {
922
                if (mpeg1_decode_block_intra(s, block[i], i) < 0)
923
                    return -1;
924
            }
925
        }else{
926
            for(i=0;i<6;i++) {
927
                if (cbp & 32) {
928
                    if (mpeg1_decode_block_inter(s, block[i], i) < 0)
929
                        return -1;
930
                } else {
931
                    s->block_last_index[i] = -1;
932
                }
933
                cbp+=cbp;
934
            }
935
        }
936
    }
937
    return 0;
938
}
939

    
940
/* as h263, but only 17 codes */
941
static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
942
{
943
    int code, sign, val, m, l, shift;
944

    
945
    code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
946
    if (code < 0) {
947
        return 0xffff;
948
    }
949
    if (code == 0) {
950
        return pred;
951
    }
952
    sign = get_bits1(&s->gb);
953
    shift = fcode - 1;
954
    val = (code - 1) << shift;
955
    if (shift > 0)
956
        val |= get_bits(&s->gb, shift);
957
    val++;
958
    if (sign)
959
        val = -val;
960
    val += pred;
961
    
962
    /* modulo decoding */
963
    l = (1 << shift) * 16;
964
    m = 2 * l;
965
    if (val < -l) {
966
        val += m;
967
    } else if (val >= l) {
968
        val -= m;
969
    }
970
    return val;
971
}
972

    
973
static inline int decode_dc(MpegEncContext *s, int component)
974
{
975
    int code, diff;
976

    
977
    if (component == 0) {
978
        code = get_vlc2(&s->gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
979
    } else {
980
        code = get_vlc2(&s->gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
981
    }
982
    if (code < 0){
983
        fprintf(stderr, "invalid dc code at %d %d\n", s->mb_x, s->mb_y);
984
        return 0xffff;
985
    }
986
    if (code == 0) {
987
        diff = 0;
988
    } else {
989
        diff = get_bits(&s->gb, code);
990
        if ((diff & (1 << (code - 1))) == 0) 
991
            diff = (-1 << code) | (diff + 1);
992
    }
993
    return diff;
994
}
995

    
996
static inline int mpeg1_decode_block_intra(MpegEncContext *s, 
997
                               DCTELEM *block, 
998
                               int n)
999
{
1000
    int level, dc, diff, i, j, run;
1001
    int component;
1002
    RLTable *rl = &rl_mpeg1;
1003
    UINT8 * const scantable= s->intra_scantable.permutated;
1004
    const UINT16 *quant_matrix= s->intra_matrix;
1005
    const int qscale= s->qscale;
1006

    
1007
    /* DC coef */
1008
    component = (n <= 3 ? 0 : n - 4 + 1);
1009
    diff = decode_dc(s, component);
1010
    if (diff >= 0xffff)
1011
        return -1;
1012
    dc = s->last_dc[component];
1013
    dc += diff;
1014
    s->last_dc[component] = dc;
1015
    block[0] = dc<<3;
1016
    dprintf("dc=%d diff=%d\n", dc, diff);
1017
    i = 0;
1018
    {
1019
        OPEN_READER(re, &s->gb);    
1020
        /* now quantify & encode AC coefs */
1021
        for(;;) {
1022
            UPDATE_CACHE(re, &s->gb);
1023
            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1024
            
1025
            if(level == 127){
1026
                break;
1027
            } else if(level != 0) {
1028
                i += run;
1029
                j = scantable[i];
1030
                level= (level*qscale*quant_matrix[j])>>3;
1031
                level= (level-1)|1;
1032
                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1033
                LAST_SKIP_BITS(re, &s->gb, 1);
1034
            } else {
1035
                /* escape */
1036
                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1037
                UPDATE_CACHE(re, &s->gb);
1038
                level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1039
                if (level == -128) {
1040
                    level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1041
                } else if (level == 0) {
1042
                    level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1043
                }
1044
                i += run;
1045
                j = scantable[i];
1046
                if(level<0){
1047
                    level= -level;
1048
                    level= (level*qscale*quant_matrix[j])>>3;
1049
                    level= (level-1)|1;
1050
                    level= -level;
1051
                }else{
1052
                    level= (level*qscale*quant_matrix[j])>>3;
1053
                    level= (level-1)|1;
1054
                }
1055
            }
1056
            if (i > 63){
1057
                fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1058
                return -1;
1059
            }
1060

    
1061
            block[j] = level;
1062
        }
1063
        CLOSE_READER(re, &s->gb);
1064
    }
1065
    s->block_last_index[n] = i;
1066
   return 0;
1067
}
1068

    
1069
static inline int mpeg1_decode_block_inter(MpegEncContext *s, 
1070
                               DCTELEM *block, 
1071
                               int n)
1072
{
1073
    int level, i, j, run;
1074
    RLTable *rl = &rl_mpeg1;
1075
    UINT8 * const scantable= s->intra_scantable.permutated;
1076
    const UINT16 *quant_matrix= s->inter_matrix;
1077
    const int qscale= s->qscale;
1078

    
1079
    {
1080
        int v;
1081
        OPEN_READER(re, &s->gb);
1082
        i = -1;
1083
        /* special case for the first coef. no need to add a second vlc table */
1084
        UPDATE_CACHE(re, &s->gb);
1085
        v= SHOW_UBITS(re, &s->gb, 2);
1086
        if (v & 2) {
1087
            LAST_SKIP_BITS(re, &s->gb, 2);
1088
            level= (3*qscale*quant_matrix[0])>>4;
1089
            level= (level-1)|1;
1090
            if(v&1)
1091
                level= -level;
1092
            block[0] = level;
1093
            i++;
1094
        }
1095

    
1096
        /* now quantify & encode AC coefs */
1097
        for(;;) {
1098
            UPDATE_CACHE(re, &s->gb);
1099
            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1100
            
1101
            if(level == 127){
1102
                break;
1103
            } else if(level != 0) {
1104
                i += run;
1105
                j = scantable[i];
1106
                level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1107
                level= (level-1)|1;
1108
                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1109
                LAST_SKIP_BITS(re, &s->gb, 1);
1110
            } else {
1111
                /* escape */
1112
                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1113
                UPDATE_CACHE(re, &s->gb);
1114
                level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1115
                if (level == -128) {
1116
                    level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1117
                } else if (level == 0) {
1118
                    level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1119
                }
1120
                i += run;
1121
                j = scantable[i];
1122
                if(level<0){
1123
                    level= -level;
1124
                    level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1125
                    level= (level-1)|1;
1126
                    level= -level;
1127
                }else{
1128
                    level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1129
                    level= (level-1)|1;
1130
                }
1131
            }
1132
            if (i > 63){
1133
                fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1134
                return -1;
1135
            }
1136

    
1137
            block[j] = level;
1138
        }
1139
        CLOSE_READER(re, &s->gb);
1140
    }
1141
    s->block_last_index[n] = i;
1142
    return 0;
1143
}
1144

    
1145
/* Also does unquantization here, since I will never support mpeg2
1146
   encoding */
1147
static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, 
1148
                               DCTELEM *block, 
1149
                               int n)
1150
{
1151
    int level, i, j, run;
1152
    RLTable *rl = &rl_mpeg1;
1153
    UINT8 * const scantable= s->intra_scantable.permutated;
1154
    const UINT16 *quant_matrix;
1155
    const int qscale= s->qscale;
1156
    int mismatch;
1157

    
1158
    mismatch = 1;
1159

    
1160
    {
1161
        int v;
1162
        OPEN_READER(re, &s->gb);
1163
        i = -1;
1164
        if (n < 4)
1165
            quant_matrix = s->inter_matrix;
1166
        else
1167
            quant_matrix = s->chroma_inter_matrix;
1168

    
1169
        /* special case for the first coef. no need to add a second vlc table */
1170
        UPDATE_CACHE(re, &s->gb);
1171
        v= SHOW_UBITS(re, &s->gb, 2);
1172
        if (v & 2) {
1173
            LAST_SKIP_BITS(re, &s->gb, 2);
1174
            level= (3*qscale*quant_matrix[0])>>5;
1175
            if(v&1)
1176
                level= -level;
1177
            block[0] = level;
1178
            mismatch ^= level;
1179
            i++;
1180
        }
1181

    
1182
        /* now quantify & encode AC coefs */
1183
        for(;;) {
1184
            UPDATE_CACHE(re, &s->gb);
1185
            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1186
            
1187
            if(level == 127){
1188
                break;
1189
            } else if(level != 0) {
1190
                i += run;
1191
                j = scantable[i];
1192
                level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1193
                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1194
                LAST_SKIP_BITS(re, &s->gb, 1);
1195
            } else {
1196
                /* escape */
1197
                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1198
                UPDATE_CACHE(re, &s->gb);
1199
                level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1200

    
1201
                i += run;
1202
                j = scantable[i];
1203
                if(level<0){
1204
                    level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
1205
                    level= -level;
1206
                }else{
1207
                    level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1208
                }
1209
            }
1210
            if (i > 63){
1211
                fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1212
                return -1;
1213
            }
1214
            
1215
            mismatch ^= level;
1216
            block[j] = level;
1217
        }
1218
        CLOSE_READER(re, &s->gb);
1219
    }
1220
    block[63] ^= (mismatch & 1);
1221
    
1222
    s->block_last_index[n] = i;
1223
    return 0;
1224
}
1225

    
1226
static inline int mpeg2_decode_block_intra(MpegEncContext *s, 
1227
                               DCTELEM *block, 
1228
                               int n)
1229
{
1230
    int level, dc, diff, i, j, run;
1231
    int component;
1232
    RLTable *rl;
1233
    UINT8 * const scantable= s->intra_scantable.permutated;
1234
    const UINT16 *quant_matrix;
1235
    const int qscale= s->qscale;
1236
    int mismatch;
1237

    
1238
    /* DC coef */
1239
    if (n < 4){
1240
        quant_matrix = s->intra_matrix;
1241
        component = 0; 
1242
    }else{
1243
        quant_matrix = s->chroma_intra_matrix;
1244
        component = n - 3;
1245
    }
1246
    diff = decode_dc(s, component);
1247
    if (diff >= 0xffff)
1248
        return -1;
1249
    dc = s->last_dc[component];
1250
    dc += diff;
1251
    s->last_dc[component] = dc;
1252
    block[0] = dc << (3 - s->intra_dc_precision);
1253
    dprintf("dc=%d\n", block[0]);
1254
    mismatch = block[0] ^ 1;
1255
    i = 0;
1256
    if (s->intra_vlc_format)
1257
        rl = &rl_mpeg2;
1258
    else
1259
        rl = &rl_mpeg1;
1260

    
1261
    {
1262
        OPEN_READER(re, &s->gb);    
1263
        /* now quantify & encode AC coefs */
1264
        for(;;) {
1265
            UPDATE_CACHE(re, &s->gb);
1266
            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1267
            
1268
            if(level == 127){
1269
                break;
1270
            } else if(level != 0) {
1271
                i += run;
1272
                j = scantable[i];
1273
                level= (level*qscale*quant_matrix[j])>>4;
1274
                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1275
                LAST_SKIP_BITS(re, &s->gb, 1);
1276
            } else {
1277
                /* escape */
1278
                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1279
                UPDATE_CACHE(re, &s->gb);
1280
                level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1281
                i += run;
1282
                j = scantable[i];
1283
                if(level<0){
1284
                    level= (-level*qscale*quant_matrix[j])>>4;
1285
                    level= -level;
1286
                }else{
1287
                    level= (level*qscale*quant_matrix[j])>>4;
1288
                }
1289
            }
1290
            if (i > 63){
1291
                fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1292
                return -1;
1293
            }
1294
            
1295
            mismatch^= level;
1296
            block[j] = level;
1297
        }
1298
        CLOSE_READER(re, &s->gb);
1299
    }
1300
    block[63]^= mismatch&1;
1301
    
1302
    s->block_last_index[n] = i;
1303
    return 0;
1304
}
1305

    
1306
/* compressed picture size */
1307
#define PICTURE_BUFFER_SIZE 100000
1308

    
1309
typedef struct Mpeg1Context {
1310
    MpegEncContext mpeg_enc_ctx;
1311
    UINT32 header_state;
1312
    int start_code; /* current start code */
1313
    UINT8 buffer[PICTURE_BUFFER_SIZE]; 
1314
    UINT8 *buf_ptr;
1315
    int buffer_size;
1316
    int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1317
    int repeat_field; /* true if we must repeat the field */
1318
} Mpeg1Context;
1319

    
1320
static int mpeg_decode_init(AVCodecContext *avctx)
1321
{
1322
    Mpeg1Context *s = avctx->priv_data;
1323
    
1324
    s->mpeg_enc_ctx.flags= avctx->flags;
1325
    common_init(&s->mpeg_enc_ctx);
1326
    init_vlcs(&s->mpeg_enc_ctx);
1327

    
1328
    s->header_state = 0xff;
1329
    s->mpeg_enc_ctx_allocated = 0;
1330
    s->buffer_size = PICTURE_BUFFER_SIZE;
1331
    s->start_code = -1;
1332
    s->buf_ptr = s->buffer;
1333
    s->mpeg_enc_ctx.picture_number = 0;
1334
    s->repeat_field = 0;
1335
    s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1336
    avctx->mbskip_table= s->mpeg_enc_ctx.mbskip_table;
1337
    return 0;
1338
}
1339

    
1340
/* return the 8 bit start code value and update the search
1341
   state. Return -1 if no start code found */
1342
static int find_start_code(UINT8 **pbuf_ptr, UINT8 *buf_end, 
1343
                           UINT32 *header_state)
1344
{
1345
    UINT8 *buf_ptr;
1346
    unsigned int state, v;
1347
    int val;
1348

    
1349
    state = *header_state;
1350
    buf_ptr = *pbuf_ptr;
1351
    while (buf_ptr < buf_end) {
1352
        v = *buf_ptr++;
1353
        if (state == 0x000001) {
1354
            state = ((state << 8) | v) & 0xffffff;
1355
            val = state;
1356
            goto found;
1357
        }
1358
        state = ((state << 8) | v) & 0xffffff;
1359
    }
1360
    val = -1;
1361
 found:
1362
    *pbuf_ptr = buf_ptr;
1363
    *header_state = state;
1364
    return val;
1365
}
1366

    
1367
static int mpeg1_decode_picture(AVCodecContext *avctx, 
1368
                                UINT8 *buf, int buf_size)
1369
{
1370
    Mpeg1Context *s1 = avctx->priv_data;
1371
    MpegEncContext *s = &s1->mpeg_enc_ctx;
1372
    int ref, f_code;
1373

    
1374
    init_get_bits(&s->gb, buf, buf_size);
1375

    
1376
    ref = get_bits(&s->gb, 10); /* temporal ref */
1377
    s->pict_type = get_bits(&s->gb, 3);
1378
    dprintf("pict_type=%d number=%d\n", s->pict_type, s->picture_number);
1379
    skip_bits(&s->gb, 16);
1380
    if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
1381
        s->full_pel[0] = get_bits1(&s->gb);
1382
        f_code = get_bits(&s->gb, 3);
1383
        if (f_code == 0)
1384
            return -1;
1385
        s->mpeg_f_code[0][0] = f_code;
1386
        s->mpeg_f_code[0][1] = f_code;
1387
    }
1388
    if (s->pict_type == B_TYPE) {
1389
        s->full_pel[1] = get_bits1(&s->gb);
1390
        f_code = get_bits(&s->gb, 3);
1391
        if (f_code == 0)
1392
            return -1;
1393
        s->mpeg_f_code[1][0] = f_code;
1394
        s->mpeg_f_code[1][1] = f_code;
1395
    }
1396
    s->y_dc_scale = 8;
1397
    s->c_dc_scale = 8;
1398
    s->first_slice = 1;
1399
    return 0;
1400
}
1401

    
1402
static void mpeg_decode_sequence_extension(MpegEncContext *s)
1403
{
1404
    int horiz_size_ext, vert_size_ext;
1405
    int bit_rate_ext, vbv_buf_ext, low_delay;
1406
    int frame_rate_ext_n, frame_rate_ext_d;
1407

    
1408
    skip_bits(&s->gb, 8); /* profil and level */
1409
    s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1410
    skip_bits(&s->gb, 2); /* chroma_format */
1411
    horiz_size_ext = get_bits(&s->gb, 2);
1412
    vert_size_ext = get_bits(&s->gb, 2);
1413
    s->width |= (horiz_size_ext << 12);
1414
    s->height |= (vert_size_ext << 12);
1415
    bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1416
    s->bit_rate = ((s->bit_rate / 400) | (bit_rate_ext << 12)) * 400;
1417
    skip_bits1(&s->gb); /* marker */
1418
    vbv_buf_ext = get_bits(&s->gb, 8);
1419
    low_delay = get_bits1(&s->gb);
1420
    frame_rate_ext_n = get_bits(&s->gb, 2);
1421
    frame_rate_ext_d = get_bits(&s->gb, 5);
1422
    if (frame_rate_ext_d >= 1)
1423
        s->frame_rate = (s->frame_rate * frame_rate_ext_n) / frame_rate_ext_d;
1424
    dprintf("sequence extension\n");
1425
    s->mpeg2 = 1;
1426
    s->avctx->sub_id = 2; /* indicates mpeg2 found */
1427
}
1428

    
1429
static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1430
{
1431
    int i, v, j;
1432

    
1433
    dprintf("matrix extension\n");
1434

    
1435
    if (get_bits1(&s->gb)) {
1436
        for(i=0;i<64;i++) {
1437
            v = get_bits(&s->gb, 8);
1438
            j = s->intra_scantable.permutated[i];
1439
            s->intra_matrix[j] = v;
1440
            s->chroma_intra_matrix[j] = v;
1441
        }
1442
    }
1443
    if (get_bits1(&s->gb)) {
1444
        for(i=0;i<64;i++) {
1445
            v = get_bits(&s->gb, 8);
1446
            j = s->intra_scantable.permutated[i];
1447
            s->inter_matrix[j] = v;
1448
            s->chroma_inter_matrix[j] = v;
1449
        }
1450
    }
1451
    if (get_bits1(&s->gb)) {
1452
        for(i=0;i<64;i++) {
1453
            v = get_bits(&s->gb, 8);
1454
            j = s->intra_scantable.permutated[i];
1455
            s->chroma_intra_matrix[j] = v;
1456
        }
1457
    }
1458
    if (get_bits1(&s->gb)) {
1459
        for(i=0;i<64;i++) {
1460
            v = get_bits(&s->gb, 8);
1461
            j = s->intra_scantable.permutated[i];
1462
            s->chroma_inter_matrix[j] = v;
1463
        }
1464
    }
1465
}
1466

    
1467
static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1468
{
1469
    s->full_pel[0] = s->full_pel[1] = 0;
1470
    s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1471
    s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1472
    s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1473
    s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1474
    s->intra_dc_precision = get_bits(&s->gb, 2);
1475
    s->picture_structure = get_bits(&s->gb, 2);
1476
    s->top_field_first = get_bits1(&s->gb);
1477
    s->frame_pred_frame_dct = get_bits1(&s->gb);
1478
    s->concealment_motion_vectors = get_bits1(&s->gb);
1479
    s->q_scale_type = get_bits1(&s->gb);
1480
    s->intra_vlc_format = get_bits1(&s->gb);
1481
    s->alternate_scan = get_bits1(&s->gb);
1482
    s->repeat_first_field = get_bits1(&s->gb);
1483
    s->chroma_420_type = get_bits1(&s->gb);
1484
    s->progressive_frame = get_bits1(&s->gb);
1485
    
1486
    if(s->alternate_scan){
1487
        ff_init_scantable(s, &s->inter_scantable  , ff_alternate_vertical_scan);
1488
        ff_init_scantable(s, &s->intra_scantable  , ff_alternate_vertical_scan);
1489
        ff_init_scantable(s, &s->intra_h_scantable, ff_alternate_vertical_scan);
1490
        ff_init_scantable(s, &s->intra_v_scantable, ff_alternate_vertical_scan);
1491
    }else{
1492
        ff_init_scantable(s, &s->inter_scantable  , ff_zigzag_direct);
1493
        ff_init_scantable(s, &s->intra_scantable  , ff_zigzag_direct);
1494
        ff_init_scantable(s, &s->intra_h_scantable, ff_alternate_horizontal_scan);
1495
        ff_init_scantable(s, &s->intra_v_scantable, ff_alternate_vertical_scan);
1496
    }
1497
    
1498
    /* composite display not parsed */
1499
    dprintf("intra_dc_precision=%d\n", s->intra_dc_precision);
1500
    dprintf("picture_structure=%d\n", s->picture_structure);
1501
    dprintf("top field first=%d\n", s->top_field_first);
1502
    dprintf("repeat first field=%d\n", s->repeat_first_field);
1503
    dprintf("conceal=%d\n", s->concealment_motion_vectors);
1504
    dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
1505
    dprintf("alternate_scan=%d\n", s->alternate_scan);
1506
    dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1507
    dprintf("progressive_frame=%d\n", s->progressive_frame);
1508
}
1509

    
1510
static void mpeg_decode_extension(AVCodecContext *avctx, 
1511
                                  UINT8 *buf, int buf_size)
1512
{
1513
    Mpeg1Context *s1 = avctx->priv_data;
1514
    MpegEncContext *s = &s1->mpeg_enc_ctx;
1515
    int ext_type;
1516

    
1517
    init_get_bits(&s->gb, buf, buf_size);
1518
    
1519
    ext_type = get_bits(&s->gb, 4);
1520
    switch(ext_type) {
1521
    case 0x1:
1522
        /* sequence ext */
1523
        mpeg_decode_sequence_extension(s);
1524
        break;
1525
    case 0x3:
1526
        /* quant matrix extension */
1527
        mpeg_decode_quant_matrix_extension(s);
1528
        break;
1529
    case 0x8:
1530
        /* picture extension */
1531
        mpeg_decode_picture_coding_extension(s);
1532
        break;
1533
    }
1534
}
1535

    
1536
/* return 1 if end of frame */
1537
static int mpeg_decode_slice(AVCodecContext *avctx, 
1538
                              AVPicture *pict,
1539
                              int start_code,
1540
                              UINT8 *buf, int buf_size)
1541
{
1542
    Mpeg1Context *s1 = avctx->priv_data;
1543
    MpegEncContext *s = &s1->mpeg_enc_ctx;
1544
    int ret;
1545

    
1546
    start_code = (start_code - 1) & 0xff;
1547
    if (start_code >= s->mb_height){
1548
        fprintf(stderr, "slice below image (%d >= %d)\n", start_code, s->mb_height);
1549
        return -1;
1550
    }
1551
    s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
1552
    s->last_dc[1] = s->last_dc[0];
1553
    s->last_dc[2] = s->last_dc[0];
1554
    memset(s->last_mv, 0, sizeof(s->last_mv));
1555
    /* start frame decoding */
1556
    if (s->first_slice) {
1557
        s->first_slice = 0;
1558
        MPV_frame_start(s, avctx);
1559
    }
1560

    
1561
    init_get_bits(&s->gb, buf, buf_size);
1562

    
1563
    s->qscale = get_qscale(s);
1564
    /* extra slice info */
1565
    while (get_bits1(&s->gb) != 0) {
1566
        skip_bits(&s->gb, 8);
1567
    }
1568

    
1569
    s->mb_x=0;
1570
    for(;;) {
1571
        int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1572
        if (code < 0)
1573
            return -1; /* error = end of slice, but empty slice is bad or?*/
1574
        if (code >= 33) {
1575
            if (code == 33) {
1576
                s->mb_x += 33;
1577
            }
1578
            /* otherwise, stuffing, nothing to do */
1579
        } else {
1580
            s->mb_x += code;
1581
            break;
1582
        }
1583
    }
1584
    s->mb_y = start_code;
1585
    s->mb_incr= 1;
1586

    
1587
    for(;;) {
1588
        clear_blocks(s->block[0]);
1589
        emms_c();
1590
        
1591
        ret = mpeg_decode_mb(s, s->block);
1592
        dprintf("ret=%d\n", ret);
1593
        if (ret < 0)
1594
            return -1;
1595
    
1596
        MPV_decode_mb(s, s->block);
1597

    
1598
        if (++s->mb_x >= s->mb_width) {
1599
            if (    avctx->draw_horiz_band 
1600
                && (s->num_available_buffers>=1 || (!s->has_b_frames)) ) {
1601
                UINT8 *src_ptr[3];
1602
                int y, h, offset;
1603
                y = s->mb_y * 16;
1604
                h = s->height - y;
1605
                if (h > 16)
1606
                    h = 16;
1607
                offset = y * s->linesize;
1608
                if(s->pict_type==B_TYPE || (!s->has_b_frames)){
1609
                    src_ptr[0] = s->current_picture[0] + offset;
1610
                    src_ptr[1] = s->current_picture[1] + (offset >> 2);
1611
                    src_ptr[2] = s->current_picture[2] + (offset >> 2);
1612
                } else {
1613
                    src_ptr[0] = s->last_picture[0] + offset;
1614
                    src_ptr[1] = s->last_picture[1] + (offset >> 2);
1615
                    src_ptr[2] = s->last_picture[2] + (offset >> 2);
1616
                }
1617
                avctx->draw_horiz_band(avctx, src_ptr, s->linesize,
1618
                                   y, s->width, h);
1619
            }
1620

    
1621
            s->mb_x = 0;
1622
            s->mb_y++;
1623
            PRINT_QP("%s", "\n");
1624
        }
1625
        PRINT_QP("%2d", s->qscale);
1626

    
1627
        /* skip mb handling */
1628
        if (s->mb_incr == 0) {
1629
            /* read again increment */
1630
            s->mb_incr = 1;
1631
            for(;;) {
1632
                int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1633
                if (code < 0)
1634
                    goto eos; /* error = end of slice */
1635
                if (code >= 33) {
1636
                    if (code == 33) {
1637
                        s->mb_incr += 33;
1638
                    }
1639
                    /* otherwise, stuffing, nothing to do */
1640
                } else {
1641
                    s->mb_incr += code;
1642
                    break;
1643
                }
1644
            }
1645
        }
1646
        if(s->mb_y >= s->mb_height){
1647
            fprintf(stderr, "slice too long\n");
1648
            return -1;
1649
        }
1650
    }
1651
eos: //end of slice
1652
    
1653
    emms_c();
1654

    
1655
    /* end of slice reached */
1656
    if (/*s->mb_x == 0 &&*/
1657
        s->mb_y == s->mb_height) {
1658
        /* end of image */
1659
        UINT8 **picture;
1660

    
1661
        MPV_frame_end(s);
1662

    
1663
        /* XXX: incorrect reported qscale for mpeg2 */
1664
        if (s->pict_type == B_TYPE) {
1665
            picture = s->current_picture;
1666
            avctx->quality = s->qscale;
1667
        } else {
1668
            /* latency of 1 frame for I and P frames */
1669
            /* XXX: use another variable than picture_number */
1670
            if (s->picture_number == 0) {
1671
                picture = NULL;
1672
            } else {
1673
                picture = s->last_picture;
1674
                avctx->quality = s->last_qscale;
1675
            }
1676
            s->last_qscale = s->qscale;
1677
            s->picture_number++;
1678
        }
1679
        if (picture) {
1680
            pict->data[0] = picture[0];
1681
            pict->data[1] = picture[1];
1682
            pict->data[2] = picture[2];
1683
            pict->linesize[0] = s->linesize;
1684
            pict->linesize[1] = s->uvlinesize;
1685
            pict->linesize[2] = s->uvlinesize;
1686
            return 1;
1687
        } else {
1688
            return 0;
1689
        }
1690
    } else {
1691
        return 0;
1692
    }
1693
}
1694

    
1695
static int mpeg1_decode_sequence(AVCodecContext *avctx, 
1696
                                 UINT8 *buf, int buf_size)
1697
{
1698
    Mpeg1Context *s1 = avctx->priv_data;
1699
    MpegEncContext *s = &s1->mpeg_enc_ctx;
1700
    int width, height, i, v, j;
1701

    
1702
    init_get_bits(&s->gb, buf, buf_size);
1703

    
1704
    width = get_bits(&s->gb, 12);
1705
    height = get_bits(&s->gb, 12);
1706
    skip_bits(&s->gb, 4);
1707
    s->frame_rate_index = get_bits(&s->gb, 4);
1708
    if (s->frame_rate_index == 0)
1709
        return -1;
1710
    s->bit_rate = get_bits(&s->gb, 18) * 400;
1711
    if (get_bits1(&s->gb) == 0) /* marker */
1712
        return -1;
1713
    if (width <= 0 || height <= 0 ||
1714
        (width % 2) != 0 || (height % 2) != 0)
1715
        return -1;
1716
    if (width != s->width ||
1717
        height != s->height) {
1718
        /* start new mpeg1 context decoding */
1719
        s->out_format = FMT_MPEG1;
1720
        if (s1->mpeg_enc_ctx_allocated) {
1721
            MPV_common_end(s);
1722
        }
1723
        s->width = width;
1724
        s->height = height;
1725
        avctx->has_b_frames= s->has_b_frames = 1;
1726
        s->avctx = avctx;
1727
        avctx->width = width;
1728
        avctx->height = height;
1729
        if (s->frame_rate_index >= 9) {
1730
            /* at least give a valid frame rate (some old mpeg1 have this) */
1731
            avctx->frame_rate = 25 * FRAME_RATE_BASE;
1732
        } else {
1733
            avctx->frame_rate = frame_rate_tab[s->frame_rate_index];
1734
        }
1735
        s->frame_rate = avctx->frame_rate;
1736
        avctx->bit_rate = s->bit_rate;
1737
        
1738
        if (MPV_common_init(s) < 0)
1739
            return -1;
1740
        s1->mpeg_enc_ctx_allocated = 1;
1741
    }
1742

    
1743
    skip_bits(&s->gb, 10); /* vbv_buffer_size */
1744
    skip_bits(&s->gb, 1);
1745

    
1746
    /* get matrix */
1747
    if (get_bits1(&s->gb)) {
1748
        for(i=0;i<64;i++) {
1749
            v = get_bits(&s->gb, 8);
1750
            j = s->intra_scantable.permutated[i];
1751
            s->intra_matrix[j] = v;
1752
            s->chroma_intra_matrix[j] = v;
1753
        }
1754
#ifdef DEBUG
1755
        dprintf("intra matrix present\n");
1756
        for(i=0;i<64;i++)
1757
            dprintf(" %d", s->intra_matrix[s->intra_scantable.permutated[i]]);
1758
        printf("\n");
1759
#endif
1760
    } else {
1761
        for(i=0;i<64;i++) {
1762
            int j= s->idct_permutation[i];
1763
            v = ff_mpeg1_default_intra_matrix[i];
1764
            s->intra_matrix[j] = v;
1765
            s->chroma_intra_matrix[j] = v;
1766
        }
1767
    }
1768
    if (get_bits1(&s->gb)) {
1769
        for(i=0;i<64;i++) {
1770
            v = get_bits(&s->gb, 8);
1771
            j = s->intra_scantable.permutated[i];
1772
            s->inter_matrix[j] = v;
1773
            s->chroma_inter_matrix[j] = v;
1774
        }
1775
#ifdef DEBUG
1776
        dprintf("non intra matrix present\n");
1777
        for(i=0;i<64;i++)
1778
            dprintf(" %d", s->inter_matrix[s->intra_scantable.permutated[i]]);
1779
        printf("\n");
1780
#endif
1781
    } else {
1782
        for(i=0;i<64;i++) {
1783
            int j= s->idct_permutation[i];
1784
            v = ff_mpeg1_default_non_intra_matrix[i];
1785
            s->inter_matrix[j] = v;
1786
            s->chroma_inter_matrix[j] = v;
1787
        }
1788
    }
1789

    
1790
    /* we set mpeg2 parameters so that it emulates mpeg1 */
1791
    s->progressive_sequence = 1;
1792
    s->progressive_frame = 1;
1793
    s->picture_structure = PICT_FRAME;
1794
    s->frame_pred_frame_dct = 1;
1795
    s->mpeg2 = 0;
1796
    avctx->sub_id = 1; /* indicates mpeg1 */
1797
    return 0;
1798
}
1799

    
1800
/* handle buffering and image synchronisation */
1801
static int mpeg_decode_frame(AVCodecContext *avctx, 
1802
                             void *data, int *data_size,
1803
                             UINT8 *buf, int buf_size)
1804
{
1805
    Mpeg1Context *s = avctx->priv_data;
1806
    UINT8 *buf_end, *buf_ptr, *buf_start;
1807
    int len, start_code_found, ret, code, start_code, input_size;
1808
    AVPicture *picture = data;
1809
    MpegEncContext *s2 = &s->mpeg_enc_ctx;
1810
            
1811
    dprintf("fill_buffer\n");
1812

    
1813
    *data_size = 0;
1814

    
1815
    /* special case for last picture */
1816
    if (buf_size == 0) {
1817
        if (s2->picture_number > 0) {
1818
            picture->data[0] = s2->next_picture[0];
1819
            picture->data[1] = s2->next_picture[1];
1820
            picture->data[2] = s2->next_picture[2];
1821
            picture->linesize[0] = s2->linesize;
1822
            picture->linesize[1] = s2->uvlinesize;
1823
            picture->linesize[2] = s2->uvlinesize;
1824
            *data_size = sizeof(AVPicture);
1825
        }
1826
        return 0;
1827
    }
1828

    
1829
    buf_ptr = buf;
1830
    buf_end = buf + buf_size;
1831

    
1832
#if 0    
1833
    if (s->repeat_field % 2 == 1) { 
1834
        s->repeat_field++;
1835
        //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
1836
        //        s2->picture_number, s->repeat_field);
1837
        if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
1838
            *data_size = sizeof(AVPicture);
1839
            goto the_end;
1840
        }
1841
    }
1842
#endif
1843
    while (buf_ptr < buf_end) {
1844
        buf_start = buf_ptr;
1845
        /* find start next code */
1846
        code = find_start_code(&buf_ptr, buf_end, &s->header_state);
1847
        if (code >= 0) {
1848
            start_code_found = 1;
1849
        } else {
1850
            start_code_found = 0;
1851
        }
1852
        /* copy to buffer */
1853
        len = buf_ptr - buf_start;
1854
        if (len + (s->buf_ptr - s->buffer) > s->buffer_size) {
1855
            /* data too big : flush */
1856
            s->buf_ptr = s->buffer;
1857
            if (start_code_found)
1858
                s->start_code = code;
1859
        } else {
1860
            memcpy(s->buf_ptr, buf_start, len);
1861
            s->buf_ptr += len;
1862
            if(   (s2->flags&CODEC_FLAG_NOT_TRUNCATED) && (!start_code_found) 
1863
               && s->buf_ptr+4<s->buffer+s->buffer_size){
1864
                start_code_found= 1;
1865
                code= 0x1FF;
1866
                s->header_state=0xFF;
1867
                s->buf_ptr[0]=0;
1868
                s->buf_ptr[1]=0;
1869
                s->buf_ptr[2]=1;
1870
                s->buf_ptr[3]=0xFF;
1871
                s->buf_ptr+=4;
1872
            }
1873
            if (start_code_found) {
1874
                /* prepare data for next start code */
1875
                input_size = s->buf_ptr - s->buffer;
1876
                start_code = s->start_code;
1877
                s->buf_ptr = s->buffer;
1878
                s->start_code = code;
1879
                switch(start_code) {
1880
                case SEQ_START_CODE:
1881
                    mpeg1_decode_sequence(avctx, s->buffer, 
1882
                                          input_size);
1883
                    break;
1884
                            
1885
                case PICTURE_START_CODE:
1886
                    /* we have a complete image : we try to decompress it */
1887
                    mpeg1_decode_picture(avctx, 
1888
                                         s->buffer, input_size);
1889
                    break;
1890
                case EXT_START_CODE:
1891
                    mpeg_decode_extension(avctx,
1892
                                          s->buffer, input_size);
1893
                    break;
1894
                default:
1895
                    if (start_code >= SLICE_MIN_START_CODE &&
1896
                        start_code <= SLICE_MAX_START_CODE) {
1897
                        ret = mpeg_decode_slice(avctx, picture,
1898
                                                start_code, s->buffer, input_size);
1899
                        if (ret == 1) {
1900
                            /* got a picture: exit */
1901
                            /* first check if we must repeat the frame */
1902
                            avctx->repeat_pict = 0;
1903
#if 0
1904
                            if (s2->progressive_frame && s2->repeat_first_field) {
1905
                                //fprintf(stderr,"\nRepeat this frame: %d! pict: %d",avctx->frame_number,s2->picture_number);
1906
                                //s2->repeat_first_field = 0;
1907
                                //s2->progressive_frame = 0;
1908
                                if (++s->repeat_field > 2)
1909
                                    s->repeat_field = 0;
1910
                                avctx->repeat_pict = 1;
1911
                            }
1912
#endif                      
1913
                            if (s2->repeat_first_field) {
1914
                                if (s2->progressive_sequence) {
1915
                                    if (s2->top_field_first)
1916
                                        avctx->repeat_pict = 4;
1917
                                    else
1918
                                        avctx->repeat_pict = 2;
1919
                                } else if (s2->progressive_frame) {
1920
                                    avctx->repeat_pict = 1;
1921
                                }
1922
                            }         
1923
                            *data_size = sizeof(AVPicture);
1924
                            goto the_end;
1925
                        }else if(ret==-1){
1926
                            printf("Error while decoding slice\n");
1927
                        }
1928
                    }
1929
                    break;
1930
                }
1931
            }
1932
        }
1933
    }
1934
 the_end:
1935
    return buf_ptr - buf;
1936
}
1937

    
1938
static int mpeg_decode_end(AVCodecContext *avctx)
1939
{
1940
    Mpeg1Context *s = avctx->priv_data;
1941

    
1942
    if (s->mpeg_enc_ctx_allocated)
1943
        MPV_common_end(&s->mpeg_enc_ctx);
1944
    return 0;
1945
}
1946

    
1947
AVCodec mpeg_decoder = {
1948
    "mpegvideo",
1949
    CODEC_TYPE_VIDEO,
1950
    CODEC_ID_MPEG1VIDEO,
1951
    sizeof(Mpeg1Context),
1952
    mpeg_decode_init,
1953
    NULL,
1954
    mpeg_decode_end,
1955
    mpeg_decode_frame,
1956
    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
1957
};