1/*
2 * MPEG-1/2 decoder
3 * Copyright (c) 2000,2001 Fabrice Bellard
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23/**
24 * @file
25 * MPEG-1/2 decoder
26 */
27
28//#define DEBUG
29#include "internal.h"
30#include "avcodec.h"
31#include "dsputil.h"
32#include "mpegvideo.h"
33
34#include "mpeg12.h"
35#include "mpeg12data.h"
36#include "mpeg12decdata.h"
37#include "bytestream.h"
38#include "vdpau_internal.h"
39#include "xvmc_internal.h"
40
41//#undef NDEBUG
42//#include <assert.h>
43
44
45#define MV_VLC_BITS 9
46#define MBINCR_VLC_BITS 9
47#define MB_PAT_VLC_BITS 9
48#define MB_PTYPE_VLC_BITS 6
49#define MB_BTYPE_VLC_BITS 6
50
51static inline int mpeg1_decode_block_intra(MpegEncContext *s,
52                              DCTELEM *block,
53                              int n);
54static inline int mpeg1_decode_block_inter(MpegEncContext *s,
55                              DCTELEM *block,
56                              int n);
57static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
58static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
59                                        DCTELEM *block,
60                                        int n);
61static inline int mpeg2_decode_block_intra(MpegEncContext *s,
62                                    DCTELEM *block,
63                                    int n);
64static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
65static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
66static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
67static void exchange_uv(MpegEncContext *s);
68
69static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
70                                           PIX_FMT_XVMC_MPEG2_IDCT,
71                                           PIX_FMT_XVMC_MPEG2_MC,
72                                           PIX_FMT_NONE};
73
74uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
75
76
77#define INIT_2D_VLC_RL(rl, static_size)\
78{\
79    static RL_VLC_ELEM rl_vlc_table[static_size];\
80    INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
81             &rl.table_vlc[0][1], 4, 2,\
82             &rl.table_vlc[0][0], 4, 2, static_size);\
83\
84    rl.rl_vlc[0]= rl_vlc_table;\
85    init_2d_vlc_rl(&rl);\
86}
87
88static void init_2d_vlc_rl(RLTable *rl)
89{
90    int i;
91
92    for(i=0; i<rl->vlc.table_size; i++){
93        int code= rl->vlc.table[i][0];
94        int len = rl->vlc.table[i][1];
95        int level, run;
96
97        if(len==0){ // illegal code
98            run= 65;
99            level= MAX_LEVEL;
100        }else if(len<0){ //more bits needed
101            run= 0;
102            level= code;
103        }else{
104            if(code==rl->n){ //esc
105                run= 65;
106                level= 0;
107            }else if(code==rl->n+1){ //eob
108                run= 0;
109                level= 127;
110            }else{
111                run=   rl->table_run  [code] + 1;
112                level= rl->table_level[code];
113            }
114        }
115        rl->rl_vlc[0][i].len= len;
116        rl->rl_vlc[0][i].level= level;
117        rl->rl_vlc[0][i].run= run;
118    }
119}
120
121void ff_mpeg12_common_init(MpegEncContext *s)
122{
123
124    s->y_dc_scale_table=
125    s->c_dc_scale_table= ff_mpeg2_dc_scale_table[s->intra_dc_precision];
126
127}
128
129void ff_mpeg1_clean_buffers(MpegEncContext *s){
130    s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
131    s->last_dc[1] = s->last_dc[0];
132    s->last_dc[2] = s->last_dc[0];
133    memset(s->last_mv, 0, sizeof(s->last_mv));
134}
135
136
137/******************************************/
138/* decoding */
139
140static VLC mv_vlc;
141static VLC mbincr_vlc;
142static VLC mb_ptype_vlc;
143static VLC mb_btype_vlc;
144static VLC mb_pat_vlc;
145
146av_cold void ff_mpeg12_init_vlcs(void)
147{
148    static int done = 0;
149
150    if (!done) {
151        done = 1;
152
153        INIT_VLC_STATIC(&dc_lum_vlc, DC_VLC_BITS, 12,
154                 ff_mpeg12_vlc_dc_lum_bits, 1, 1,
155                 ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
156        INIT_VLC_STATIC(&dc_chroma_vlc,  DC_VLC_BITS, 12,
157                 ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
158                 ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
159        INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
160                 &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
161                 &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
162        INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
163                 &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
164                 &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
165        INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
166                 &ff_mpeg12_mbPatTable[0][1], 2, 1,
167                 &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
168
169        INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
170                 &table_mb_ptype[0][1], 2, 1,
171                 &table_mb_ptype[0][0], 2, 1, 64);
172        INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
173                 &table_mb_btype[0][1], 2, 1,
174                 &table_mb_btype[0][0], 2, 1, 64);
175        init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
176        init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
177
178        INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
179        INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
180    }
181}
182
183static inline int get_dmv(MpegEncContext *s)
184{
185    if(get_bits1(&s->gb))
186        return 1 - (get_bits1(&s->gb) << 1);
187    else
188        return 0;
189}
190
191static inline int get_qscale(MpegEncContext *s)
192{
193    int qscale = get_bits(&s->gb, 5);
194    if (s->q_scale_type) {
195        return non_linear_qscale[qscale];
196    } else {
197        return qscale << 1;
198    }
199}
200
201/* motion type (for MPEG-2) */
202#define MT_FIELD 1
203#define MT_FRAME 2
204#define MT_16X8  2
205#define MT_DMV   3
206
207static int mpeg_decode_mb(MpegEncContext *s,
208                          DCTELEM block[12][64])
209{
210    int i, j, k, cbp, val, mb_type, motion_type;
211    const int mb_block_count = 4 + (1<< s->chroma_format);
212
213    dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
214
215    assert(s->mb_skipped==0);
216
217    if (s->mb_skip_run-- != 0) {
218        if (s->pict_type == FF_P_TYPE) {
219            s->mb_skipped = 1;
220            s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
221        } else {
222            int mb_type;
223
224            if(s->mb_x)
225                mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
226            else
227                mb_type= s->current_picture.mb_type[ s->mb_width + (s->mb_y-1)*s->mb_stride - 1]; // FIXME not sure if this is allowed in MPEG at all
228            if(IS_INTRA(mb_type))
229                return -1;
230
231            s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
232                mb_type | MB_TYPE_SKIP;
233//            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
234
235            if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
236                s->mb_skipped = 1;
237        }
238
239        return 0;
240    }
241
242    switch(s->pict_type) {
243    default:
244    case FF_I_TYPE:
245        if (get_bits1(&s->gb) == 0) {
246            if (get_bits1(&s->gb) == 0){
247                av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
248                return -1;
249            }
250            mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
251        } else {
252            mb_type = MB_TYPE_INTRA;
253        }
254        break;
255    case FF_P_TYPE:
256        mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
257        if (mb_type < 0){
258            av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
259            return -1;
260        }
261        mb_type = ptype2mb_type[ mb_type ];
262        break;
263    case FF_B_TYPE:
264        mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
265        if (mb_type < 0){
266            av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
267            return -1;
268        }
269        mb_type = btype2mb_type[ mb_type ];
270        break;
271    }
272    dprintf(s->avctx, "mb_type=%x\n", mb_type);
273//    motion_type = 0; /* avoid warning */
274    if (IS_INTRA(mb_type)) {
275        s->dsp.clear_blocks(s->block[0]);
276
277        if(!s->chroma_y_shift){
278            s->dsp.clear_blocks(s->block[6]);
279        }
280
281        /* compute DCT type */
282        if (s->picture_structure == PICT_FRAME && //FIXME add an interlaced_dct coded var?
283            !s->frame_pred_frame_dct) {
284            s->interlaced_dct = get_bits1(&s->gb);
285        }
286
287        if (IS_QUANT(mb_type))
288            s->qscale = get_qscale(s);
289
290        if (s->concealment_motion_vectors) {
291            /* just parse them */
292            if (s->picture_structure != PICT_FRAME)
293                skip_bits1(&s->gb); /* field select */
294
295            s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
296                mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
297            s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
298                mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
299
300            skip_bits1(&s->gb); /* marker */
301        }else
302            memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
303        s->mb_intra = 1;
304        //if 1, we memcpy blocks in xvmcvideo
305        if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1){
306            ff_xvmc_pack_pblocks(s,-1);//inter are always full blocks
307            if(s->swap_uv){
308                exchange_uv(s);
309            }
310        }
311
312        if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
313            if(s->flags2 & CODEC_FLAG2_FAST){
314                for(i=0;i<6;i++) {
315                    mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
316                }
317            }else{
318                for(i=0;i<mb_block_count;i++) {
319                    if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
320                        return -1;
321                }
322            }
323        } else {
324            for(i=0;i<6;i++) {
325                if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
326                    return -1;
327            }
328        }
329    } else {
330        if (mb_type & MB_TYPE_ZERO_MV){
331            assert(mb_type & MB_TYPE_CBP);
332
333            s->mv_dir = MV_DIR_FORWARD;
334            if(s->picture_structure == PICT_FRAME){
335                if(!s->frame_pred_frame_dct)
336                    s->interlaced_dct = get_bits1(&s->gb);
337                s->mv_type = MV_TYPE_16X16;
338            }else{
339                s->mv_type = MV_TYPE_FIELD;
340                mb_type |= MB_TYPE_INTERLACED;
341                s->field_select[0][0]= s->picture_structure - 1;
342            }
343
344            if (IS_QUANT(mb_type))
345                s->qscale = get_qscale(s);
346
347            s->last_mv[0][0][0] = 0;
348            s->last_mv[0][0][1] = 0;
349            s->last_mv[0][1][0] = 0;
350            s->last_mv[0][1][1] = 0;
351            s->mv[0][0][0] = 0;
352            s->mv[0][0][1] = 0;
353        }else{
354            assert(mb_type & MB_TYPE_L0L1);
355//FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
356            /* get additional motion vector type */
357            if (s->frame_pred_frame_dct)
358                motion_type = MT_FRAME;
359            else{
360                motion_type = get_bits(&s->gb, 2);
361                if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
362                    s->interlaced_dct = get_bits1(&s->gb);
363            }
364
365            if (IS_QUANT(mb_type))
366                s->qscale = get_qscale(s);
367
368            /* motion vectors */
369            s->mv_dir= (mb_type>>13)&3;
370            dprintf(s->avctx, "motion_type=%d\n", motion_type);
371            switch(motion_type) {
372            case MT_FRAME: /* or MT_16X8 */
373                if (s->picture_structure == PICT_FRAME) {
374                    mb_type |= MB_TYPE_16x16;
375                    s->mv_type = MV_TYPE_16X16;
376                    for(i=0;i<2;i++) {
377                        if (USES_LIST(mb_type, i)) {
378                            /* MT_FRAME */
379                            s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
380                                mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
381                            s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
382                                mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
383                            /* full_pel: only for MPEG-1 */
384                            if (s->full_pel[i]){
385                                s->mv[i][0][0] <<= 1;
386                                s->mv[i][0][1] <<= 1;
387                            }
388                        }
389                    }
390                } else {
391                    mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
392                    s->mv_type = MV_TYPE_16X8;
393                    for(i=0;i<2;i++) {
394                        if (USES_LIST(mb_type, i)) {
395                            /* MT_16X8 */
396                            for(j=0;j<2;j++) {
397                                s->field_select[i][j] = get_bits1(&s->gb);
398                                for(k=0;k<2;k++) {
399                                    val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
400                                                             s->last_mv[i][j][k]);
401                                    s->last_mv[i][j][k] = val;
402                                    s->mv[i][j][k] = val;
403                                }
404                            }
405                        }
406                    }
407                }
408                break;
409            case MT_FIELD:
410                s->mv_type = MV_TYPE_FIELD;
411                if (s->picture_structure == PICT_FRAME) {
412                    mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
413                    for(i=0;i<2;i++) {
414                        if (USES_LIST(mb_type, i)) {
415                            for(j=0;j<2;j++) {
416                                s->field_select[i][j] = get_bits1(&s->gb);
417                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
418                                                         s->last_mv[i][j][0]);
419                                s->last_mv[i][j][0] = val;
420                                s->mv[i][j][0] = val;
421                                dprintf(s->avctx, "fmx=%d\n", val);
422                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
423                                                         s->last_mv[i][j][1] >> 1);
424                                s->last_mv[i][j][1] = val << 1;
425                                s->mv[i][j][1] = val;
426                                dprintf(s->avctx, "fmy=%d\n", val);
427                            }
428                        }
429                    }
430                } else {
431                    mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
432                    for(i=0;i<2;i++) {
433                        if (USES_LIST(mb_type, i)) {
434                            s->field_select[i][0] = get_bits1(&s->gb);
435                            for(k=0;k<2;k++) {
436                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
437                                                         s->last_mv[i][0][k]);
438                                s->last_mv[i][0][k] = val;
439                                s->last_mv[i][1][k] = val;
440                                s->mv[i][0][k] = val;
441                            }
442                        }
443                    }
444                }
445                break;
446            case MT_DMV:
447                s->mv_type = MV_TYPE_DMV;
448                for(i=0;i<2;i++) {
449                    if (USES_LIST(mb_type, i)) {
450                        int dmx, dmy, mx, my, m;
451                        const int my_shift= s->picture_structure == PICT_FRAME;
452
453                        mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
454                                                s->last_mv[i][0][0]);
455                        s->last_mv[i][0][0] = mx;
456                        s->last_mv[i][1][0] = mx;
457                        dmx = get_dmv(s);
458                        my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
459                                                s->last_mv[i][0][1] >> my_shift);
460                        dmy = get_dmv(s);
461
462
463                        s->last_mv[i][0][1] = my<<my_shift;
464                        s->last_mv[i][1][1] = my<<my_shift;
465
466                        s->mv[i][0][0] = mx;
467                        s->mv[i][0][1] = my;
468                        s->mv[i][1][0] = mx;//not used
469                        s->mv[i][1][1] = my;//not used
470
471                        if (s->picture_structure == PICT_FRAME) {
472                            mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
473
474                            //m = 1 + 2 * s->top_field_first;
475                            m = s->top_field_first ? 1 : 3;
476
477                            /* top -> top pred */
478                            s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
479                            s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
480                            m = 4 - m;
481                            s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
482                            s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
483                        } else {
484                            mb_type |= MB_TYPE_16x16;
485
486                            s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
487                            s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
488                            if(s->picture_structure == PICT_TOP_FIELD)
489                                s->mv[i][2][1]--;
490                            else
491                                s->mv[i][2][1]++;
492                        }
493                    }
494                }
495                break;
496            default:
497                av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
498                return -1;
499            }
500        }
501
502        s->mb_intra = 0;
503        if (HAS_CBP(mb_type)) {
504            s->dsp.clear_blocks(s->block[0]);
505
506            cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
507            if(mb_block_count > 6){
508                 cbp<<= mb_block_count-6;
509                 cbp |= get_bits(&s->gb, mb_block_count-6);
510                 s->dsp.clear_blocks(s->block[6]);
511            }
512            if (cbp <= 0){
513                av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
514                return -1;
515            }
516
517            //if 1, we memcpy blocks in xvmcvideo
518            if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1){
519                ff_xvmc_pack_pblocks(s,cbp);
520                if(s->swap_uv){
521                    exchange_uv(s);
522                }
523            }
524
525            if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
526                if(s->flags2 & CODEC_FLAG2_FAST){
527                    for(i=0;i<6;i++) {
528                        if(cbp & 32) {
529                            mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
530                        } else {
531                            s->block_last_index[i] = -1;
532                        }
533                        cbp+=cbp;
534                    }
535                }else{
536                    cbp<<= 12-mb_block_count;
537
538                    for(i=0;i<mb_block_count;i++) {
539                        if ( cbp & (1<<11) ) {
540                            if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
541                                return -1;
542                        } else {
543                            s->block_last_index[i] = -1;
544                        }
545                        cbp+=cbp;
546                    }
547                }
548            } else {
549                if(s->flags2 & CODEC_FLAG2_FAST){
550                    for(i=0;i<6;i++) {
551                        if (cbp & 32) {
552                            mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
553                        } else {
554                            s->block_last_index[i] = -1;
555                        }
556                        cbp+=cbp;
557                    }
558                }else{
559                    for(i=0;i<6;i++) {
560                        if (cbp & 32) {
561                            if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
562                                return -1;
563                        } else {
564                            s->block_last_index[i] = -1;
565                        }
566                        cbp+=cbp;
567                    }
568                }
569            }
570        }else{
571            for(i=0;i<12;i++)
572                s->block_last_index[i] = -1;
573        }
574    }
575
576    s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
577
578    return 0;
579}
580
581/* as H.263, but only 17 codes */
582static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
583{
584    int code, sign, val, l, shift;
585
586    code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
587    if (code == 0) {
588        return pred;
589    }
590    if (code < 0) {
591        return 0xffff;
592    }
593
594    sign = get_bits1(&s->gb);
595    shift = fcode - 1;
596    val = code;
597    if (shift) {
598        val = (val - 1) << shift;
599        val |= get_bits(&s->gb, shift);
600        val++;
601    }
602    if (sign)
603        val = -val;
604    val += pred;
605
606    /* modulo decoding */
607    l= INT_BIT - 5 - shift;
608    val = (val<<l)>>l;
609    return val;
610}
611
612static inline int mpeg1_decode_block_intra(MpegEncContext *s,
613                               DCTELEM *block,
614                               int n)
615{
616    int level, dc, diff, i, j, run;
617    int component;
618    RLTable *rl = &ff_rl_mpeg1;
619    uint8_t * const scantable= s->intra_scantable.permutated;
620    const uint16_t *quant_matrix= s->intra_matrix;
621    const int qscale= s->qscale;
622
623    /* DC coefficient */
624    component = (n <= 3 ? 0 : n - 4 + 1);
625    diff = decode_dc(&s->gb, component);
626    if (diff >= 0xffff)
627        return -1;
628    dc = s->last_dc[component];
629    dc += diff;
630    s->last_dc[component] = dc;
631    block[0] = dc*quant_matrix[0];
632    dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
633    i = 0;
634    {
635        OPEN_READER(re, &s->gb);
636        /* now quantify & encode AC coefficients */
637        for(;;) {
638            UPDATE_CACHE(re, &s->gb);
639            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
640
641            if(level == 127){
642                break;
643            } else if(level != 0) {
644                i += run;
645                j = scantable[i];
646                level= (level*qscale*quant_matrix[j])>>4;
647                level= (level-1)|1;
648                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
649                LAST_SKIP_BITS(re, &s->gb, 1);
650            } else {
651                /* escape */
652                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
653                UPDATE_CACHE(re, &s->gb);
654                level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
655                if (level == -128) {
656                    level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
657                } else if (level == 0) {
658                    level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
659                }
660                i += run;
661                j = scantable[i];
662                if(level<0){
663                    level= -level;
664                    level= (level*qscale*quant_matrix[j])>>4;
665                    level= (level-1)|1;
666                    level= -level;
667                }else{
668                    level= (level*qscale*quant_matrix[j])>>4;
669                    level= (level-1)|1;
670                }
671            }
672            if (i > 63){
673                av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
674                return -1;
675            }
676
677            block[j] = level;
678        }
679        CLOSE_READER(re, &s->gb);
680    }
681    s->block_last_index[n] = i;
682   return 0;
683}
684
685int ff_mpeg1_decode_block_intra(MpegEncContext *s,
686                                DCTELEM *block,
687                                int n)
688{
689    return mpeg1_decode_block_intra(s, block, n);
690}
691
692static inline int mpeg1_decode_block_inter(MpegEncContext *s,
693                               DCTELEM *block,
694                               int n)
695{
696    int level, i, j, run;
697    RLTable *rl = &ff_rl_mpeg1;
698    uint8_t * const scantable= s->intra_scantable.permutated;
699    const uint16_t *quant_matrix= s->inter_matrix;
700    const int qscale= s->qscale;
701
702    {
703        OPEN_READER(re, &s->gb);
704        i = -1;
705        // special case for first coefficient, no need to add second VLC table
706        UPDATE_CACHE(re, &s->gb);
707        if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
708            level= (3*qscale*quant_matrix[0])>>5;
709            level= (level-1)|1;
710            if(GET_CACHE(re, &s->gb)&0x40000000)
711                level= -level;
712            block[0] = level;
713            i++;
714            SKIP_BITS(re, &s->gb, 2);
715            if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
716                goto end;
717        }
718#if MIN_CACHE_BITS < 19
719        UPDATE_CACHE(re, &s->gb);
720#endif
721        /* now quantify & encode AC coefficients */
722        for(;;) {
723            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
724
725            if(level != 0) {
726                i += run;
727                j = scantable[i];
728                level= ((level*2+1)*qscale*quant_matrix[j])>>5;
729                level= (level-1)|1;
730                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
731                SKIP_BITS(re, &s->gb, 1);
732            } else {
733                /* escape */
734                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
735                UPDATE_CACHE(re, &s->gb);
736                level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
737                if (level == -128) {
738                    level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
739                } else if (level == 0) {
740                    level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
741                }
742                i += run;
743                j = scantable[i];
744                if(level<0){
745                    level= -level;
746                    level= ((level*2+1)*qscale*quant_matrix[j])>>5;
747                    level= (level-1)|1;
748                    level= -level;
749                }else{
750                    level= ((level*2+1)*qscale*quant_matrix[j])>>5;
751                    level= (level-1)|1;
752                }
753            }
754            if (i > 63){
755                av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
756                return -1;
757            }
758
759            block[j] = level;
760#if MIN_CACHE_BITS < 19
761            UPDATE_CACHE(re, &s->gb);
762#endif
763            if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
764                break;
765#if MIN_CACHE_BITS >= 19
766            UPDATE_CACHE(re, &s->gb);
767#endif
768        }
769end:
770        LAST_SKIP_BITS(re, &s->gb, 2);
771        CLOSE_READER(re, &s->gb);
772    }
773    s->block_last_index[n] = i;
774    return 0;
775}
776
777static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
778{
779    int level, i, j, run;
780    RLTable *rl = &ff_rl_mpeg1;
781    uint8_t * const scantable= s->intra_scantable.permutated;
782    const int qscale= s->qscale;
783
784    {
785        OPEN_READER(re, &s->gb);
786        i = -1;
787        // special case for first coefficient, no need to add second VLC table
788        UPDATE_CACHE(re, &s->gb);
789        if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
790            level= (3*qscale)>>1;
791            level= (level-1)|1;
792            if(GET_CACHE(re, &s->gb)&0x40000000)
793                level= -level;
794            block[0] = level;
795            i++;
796            SKIP_BITS(re, &s->gb, 2);
797            if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
798                goto end;
799        }
800#if MIN_CACHE_BITS < 19
801        UPDATE_CACHE(re, &s->gb);
802#endif
803
804        /* now quantify & encode AC coefficients */
805        for(;;) {
806            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
807
808            if(level != 0) {
809                i += run;
810                j = scantable[i];
811                level= ((level*2+1)*qscale)>>1;
812                level= (level-1)|1;
813                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
814                SKIP_BITS(re, &s->gb, 1);
815            } else {
816                /* escape */
817                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
818                UPDATE_CACHE(re, &s->gb);
819                level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
820                if (level == -128) {
821                    level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
822                } else if (level == 0) {
823                    level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
824                }
825                i += run;
826                j = scantable[i];
827                if(level<0){
828                    level= -level;
829                    level= ((level*2+1)*qscale)>>1;
830                    level= (level-1)|1;
831                    level= -level;
832                }else{
833                    level= ((level*2+1)*qscale)>>1;
834                    level= (level-1)|1;
835                }
836            }
837
838            block[j] = level;
839#if MIN_CACHE_BITS < 19
840            UPDATE_CACHE(re, &s->gb);
841#endif
842            if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
843                break;
844#if MIN_CACHE_BITS >= 19
845            UPDATE_CACHE(re, &s->gb);
846#endif
847        }
848end:
849        LAST_SKIP_BITS(re, &s->gb, 2);
850        CLOSE_READER(re, &s->gb);
851    }
852    s->block_last_index[n] = i;
853    return 0;
854}
855
856
857static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
858                               DCTELEM *block,
859                               int n)
860{
861    int level, i, j, run;
862    RLTable *rl = &ff_rl_mpeg1;
863    uint8_t * const scantable= s->intra_scantable.permutated;
864    const uint16_t *quant_matrix;
865    const int qscale= s->qscale;
866    int mismatch;
867
868    mismatch = 1;
869
870    {
871        OPEN_READER(re, &s->gb);
872        i = -1;
873        if (n < 4)
874            quant_matrix = s->inter_matrix;
875        else
876            quant_matrix = s->chroma_inter_matrix;
877
878        // special case for first coefficient, no need to add second VLC table
879        UPDATE_CACHE(re, &s->gb);
880        if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
881            level= (3*qscale*quant_matrix[0])>>5;
882            if(GET_CACHE(re, &s->gb)&0x40000000)
883                level= -level;
884            block[0] = level;
885            mismatch ^= level;
886            i++;
887            SKIP_BITS(re, &s->gb, 2);
888            if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
889                goto end;
890        }
891#if MIN_CACHE_BITS < 19
892        UPDATE_CACHE(re, &s->gb);
893#endif
894
895        /* now quantify & encode AC coefficients */
896        for(;;) {
897            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
898
899            if(level != 0) {
900                i += run;
901                j = scantable[i];
902                level= ((level*2+1)*qscale*quant_matrix[j])>>5;
903                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
904                SKIP_BITS(re, &s->gb, 1);
905            } else {
906                /* escape */
907                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
908                UPDATE_CACHE(re, &s->gb);
909                level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
910
911                i += run;
912                j = scantable[i];
913                if(level<0){
914                    level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
915                    level= -level;
916                }else{
917                    level= ((level*2+1)*qscale*quant_matrix[j])>>5;
918                }
919            }
920            if (i > 63){
921                av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
922                return -1;
923            }
924
925            mismatch ^= level;
926            block[j] = level;
927#if MIN_CACHE_BITS < 19
928            UPDATE_CACHE(re, &s->gb);
929#endif
930            if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
931                break;
932#if MIN_CACHE_BITS >= 19
933            UPDATE_CACHE(re, &s->gb);
934#endif
935        }
936end:
937        LAST_SKIP_BITS(re, &s->gb, 2);
938        CLOSE_READER(re, &s->gb);
939    }
940    block[63] ^= (mismatch & 1);
941
942    s->block_last_index[n] = i;
943    return 0;
944}
945
946static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
947                               DCTELEM *block,
948                               int n)
949{
950    int level, i, j, run;
951    RLTable *rl = &ff_rl_mpeg1;
952    uint8_t * const scantable= s->intra_scantable.permutated;
953    const int qscale= s->qscale;
954    OPEN_READER(re, &s->gb);
955    i = -1;
956
957    // special case for first coefficient, no need to add second VLC table
958    UPDATE_CACHE(re, &s->gb);
959    if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
960        level= (3*qscale)>>1;
961        if(GET_CACHE(re, &s->gb)&0x40000000)
962            level= -level;
963        block[0] = level;
964        i++;
965        SKIP_BITS(re, &s->gb, 2);
966        if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
967            goto end;
968    }
969#if MIN_CACHE_BITS < 19
970    UPDATE_CACHE(re, &s->gb);
971#endif
972
973    /* now quantify & encode AC coefficients */
974    for(;;) {
975        GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
976
977        if(level != 0) {
978            i += run;
979            j = scantable[i];
980            level= ((level*2+1)*qscale)>>1;
981            level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
982            SKIP_BITS(re, &s->gb, 1);
983        } else {
984            /* escape */
985            run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
986            UPDATE_CACHE(re, &s->gb);
987            level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
988
989            i += run;
990            j = scantable[i];
991            if(level<0){
992                level= ((-level*2+1)*qscale)>>1;
993                level= -level;
994            }else{
995                level= ((level*2+1)*qscale)>>1;
996            }
997        }
998
999        block[j] = level;
1000#if MIN_CACHE_BITS < 19
1001        UPDATE_CACHE(re, &s->gb);
1002#endif
1003        if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1004            break;
1005#if MIN_CACHE_BITS >=19
1006        UPDATE_CACHE(re, &s->gb);
1007#endif
1008    }
1009end:
1010    LAST_SKIP_BITS(re, &s->gb, 2);
1011    CLOSE_READER(re, &s->gb);
1012    s->block_last_index[n] = i;
1013    return 0;
1014}
1015
1016
1017static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1018                               DCTELEM *block,
1019                               int n)
1020{
1021    int level, dc, diff, i, j, run;
1022    int component;
1023    RLTable *rl;
1024    uint8_t * const scantable= s->intra_scantable.permutated;
1025    const uint16_t *quant_matrix;
1026    const int qscale= s->qscale;
1027    int mismatch;
1028
1029    /* DC coefficient */
1030    if (n < 4){
1031        quant_matrix = s->intra_matrix;
1032        component = 0;
1033    }else{
1034        quant_matrix = s->chroma_intra_matrix;
1035        component = (n&1) + 1;
1036    }
1037    diff = decode_dc(&s->gb, component);
1038    if (diff >= 0xffff)
1039        return -1;
1040    dc = s->last_dc[component];
1041    dc += diff;
1042    s->last_dc[component] = dc;
1043    block[0] = dc << (3 - s->intra_dc_precision);
1044    dprintf(s->avctx, "dc=%d\n", block[0]);
1045    mismatch = block[0] ^ 1;
1046    i = 0;
1047    if (s->intra_vlc_format)
1048        rl = &ff_rl_mpeg2;
1049    else
1050        rl = &ff_rl_mpeg1;
1051
1052    {
1053        OPEN_READER(re, &s->gb);
1054        /* now quantify & encode AC coefficients */
1055        for(;;) {
1056            UPDATE_CACHE(re, &s->gb);
1057            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1058
1059            if(level == 127){
1060                break;
1061            } else if(level != 0) {
1062                i += run;
1063                j = scantable[i];
1064                level= (level*qscale*quant_matrix[j])>>4;
1065                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1066                LAST_SKIP_BITS(re, &s->gb, 1);
1067            } else {
1068                /* escape */
1069                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1070                UPDATE_CACHE(re, &s->gb);
1071                level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1072                i += run;
1073                j = scantable[i];
1074                if(level<0){
1075                    level= (-level*qscale*quant_matrix[j])>>4;
1076                    level= -level;
1077                }else{
1078                    level= (level*qscale*quant_matrix[j])>>4;
1079                }
1080            }
1081            if (i > 63){
1082                av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1083                return -1;
1084            }
1085
1086            mismatch^= level;
1087            block[j] = level;
1088        }
1089        CLOSE_READER(re, &s->gb);
1090    }
1091    block[63]^= mismatch&1;
1092
1093    s->block_last_index[n] = i;
1094    return 0;
1095}
1096
1097static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
1098                               DCTELEM *block,
1099                               int n)
1100{
1101    int level, dc, diff, j, run;
1102    int component;
1103    RLTable *rl;
1104    uint8_t * scantable= s->intra_scantable.permutated;
1105    const uint16_t *quant_matrix;
1106    const int qscale= s->qscale;
1107
1108    /* DC coefficient */
1109    if (n < 4){
1110        quant_matrix = s->intra_matrix;
1111        component = 0;
1112    }else{
1113        quant_matrix = s->chroma_intra_matrix;
1114        component = (n&1) + 1;
1115    }
1116    diff = decode_dc(&s->gb, component);
1117    if (diff >= 0xffff)
1118        return -1;
1119    dc = s->last_dc[component];
1120    dc += diff;
1121    s->last_dc[component] = dc;
1122    block[0] = dc << (3 - s->intra_dc_precision);
1123    if (s->intra_vlc_format)
1124        rl = &ff_rl_mpeg2;
1125    else
1126        rl = &ff_rl_mpeg1;
1127
1128    {
1129        OPEN_READER(re, &s->gb);
1130        /* now quantify & encode AC coefficients */
1131        for(;;) {
1132            UPDATE_CACHE(re, &s->gb);
1133            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1134
1135            if(level == 127){
1136                break;
1137            } else if(level != 0) {
1138                scantable += run;
1139                j = *scantable;
1140                level= (level*qscale*quant_matrix[j])>>4;
1141                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1142                LAST_SKIP_BITS(re, &s->gb, 1);
1143            } else {
1144                /* escape */
1145                run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1146                UPDATE_CACHE(re, &s->gb);
1147                level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1148                scantable += run;
1149                j = *scantable;
1150                if(level<0){
1151                    level= (-level*qscale*quant_matrix[j])>>4;
1152                    level= -level;
1153                }else{
1154                    level= (level*qscale*quant_matrix[j])>>4;
1155                }
1156            }
1157
1158            block[j] = level;
1159        }
1160        CLOSE_READER(re, &s->gb);
1161    }
1162
1163    s->block_last_index[n] = scantable - s->intra_scantable.permutated;
1164    return 0;
1165}
1166
1167typedef struct Mpeg1Context {
1168    MpegEncContext mpeg_enc_ctx;
1169    int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1170    int repeat_field; /* true if we must repeat the field */
1171    AVPanScan pan_scan; /** some temporary storage for the panscan */
1172    int slice_count;
1173    int swap_uv;//indicate VCR2
1174    int save_aspect_info;
1175    int save_width, save_height, save_progressive_seq;
1176    AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1177    int sync;                        ///< Did we reach a sync point like a GOP/SEQ/KEYFrame?
1178} Mpeg1Context;
1179
1180static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1181{
1182    Mpeg1Context *s = avctx->priv_data;
1183    MpegEncContext *s2 = &s->mpeg_enc_ctx;
1184    int i;
1185
1186    /* we need some permutation to store matrices,
1187     * until MPV_common_init() sets the real permutation. */
1188    for(i=0;i<64;i++)
1189       s2->dsp.idct_permutation[i]=i;
1190
1191    MPV_decode_defaults(s2);
1192
1193    s->mpeg_enc_ctx.avctx= avctx;
1194    s->mpeg_enc_ctx.flags= avctx->flags;
1195    s->mpeg_enc_ctx.flags2= avctx->flags2;
1196    ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1197    ff_mpeg12_init_vlcs();
1198
1199    s->mpeg_enc_ctx_allocated = 0;
1200    s->mpeg_enc_ctx.picture_number = 0;
1201    s->repeat_field = 0;
1202    s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1203    avctx->color_range= AVCOL_RANGE_MPEG;
1204    if (avctx->codec->id == CODEC_ID_MPEG1VIDEO)
1205        avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1206    else
1207        avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1208    return 0;
1209}
1210
1211static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1212                                     const uint8_t *new_perm){
1213    uint16_t temp_matrix[64];
1214    int i;
1215
1216    memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1217
1218    for(i=0;i<64;i++){
1219        matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1220    }
1221}
1222
1223static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx){
1224    Mpeg1Context *s1 = avctx->priv_data;
1225    MpegEncContext *s = &s1->mpeg_enc_ctx;
1226
1227    if(avctx->xvmc_acceleration)
1228        return avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
1229    else if(avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU){
1230        if(avctx->codec_id == CODEC_ID_MPEG1VIDEO)
1231            return PIX_FMT_VDPAU_MPEG1;
1232        else
1233            return PIX_FMT_VDPAU_MPEG2;
1234    }else{
1235        if(s->chroma_format <  2)
1236            return avctx->get_format(avctx,ff_hwaccel_pixfmt_list_420);
1237        else if(s->chroma_format == 2)
1238            return PIX_FMT_YUV422P;
1239        else
1240            return PIX_FMT_YUV444P;
1241    }
1242}
1243
1244/* Call this function when we know all parameters.
1245 * It may be called in different places for MPEG-1 and MPEG-2. */
1246static int mpeg_decode_postinit(AVCodecContext *avctx){
1247    Mpeg1Context *s1 = avctx->priv_data;
1248    MpegEncContext *s = &s1->mpeg_enc_ctx;
1249    uint8_t old_permutation[64];
1250
1251    if (
1252        (s1->mpeg_enc_ctx_allocated == 0)||
1253        avctx->coded_width  != s->width ||
1254        avctx->coded_height != s->height||
1255        s1->save_width != s->width ||
1256        s1->save_height != s->height ||
1257        s1->save_aspect_info != s->aspect_ratio_info||
1258        s1->save_progressive_seq != s->progressive_sequence ||
1259        0)
1260    {
1261
1262        if (s1->mpeg_enc_ctx_allocated) {
1263            ParseContext pc= s->parse_context;
1264            s->parse_context.buffer=0;
1265            MPV_common_end(s);
1266            s->parse_context= pc;
1267        }
1268
1269        if( (s->width == 0 )||(s->height == 0))
1270            return -2;
1271
1272        avcodec_set_dimensions(avctx, s->width, s->height);
1273        avctx->bit_rate = s->bit_rate;
1274        s1->save_aspect_info = s->aspect_ratio_info;
1275        s1->save_width = s->width;
1276        s1->save_height = s->height;
1277        s1->save_progressive_seq = s->progressive_sequence;
1278
1279        /* low_delay may be forced, in this case we will have B-frames
1280         * that behave like P-frames. */
1281        avctx->has_b_frames = !(s->low_delay);
1282
1283        assert((avctx->sub_id==1) == (avctx->codec_id==CODEC_ID_MPEG1VIDEO));
1284        if(avctx->codec_id==CODEC_ID_MPEG1VIDEO){
1285            //MPEG-1 fps
1286            avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
1287            avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
1288            //MPEG-1 aspect
1289            avctx->sample_aspect_ratio= av_d2q(
1290                    1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1291            avctx->ticks_per_frame=1;
1292        }else{//MPEG-2
1293        //MPEG-2 fps
1294            av_reduce(
1295                &s->avctx->time_base.den,
1296                &s->avctx->time_base.num,
1297                ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
1298                ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1299                1<<30);
1300            avctx->ticks_per_frame=2;
1301        //MPEG-2 aspect
1302            if(s->aspect_ratio_info > 1){
1303                //we ignore the spec here as reality does not match the spec, see for example
1304                // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
1305                if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) || 1){
1306                    s->avctx->sample_aspect_ratio=
1307                        av_div_q(
1308                         ff_mpeg2_aspect[s->aspect_ratio_info],
1309                         (AVRational){s->width, s->height}
1310                         );
1311                }else{
1312                    s->avctx->sample_aspect_ratio=
1313                        av_div_q(
1314                         ff_mpeg2_aspect[s->aspect_ratio_info],
1315                         (AVRational){s1->pan_scan.width, s1->pan_scan.height}
1316                        );
1317                }
1318            }else{
1319                s->avctx->sample_aspect_ratio=
1320                    ff_mpeg2_aspect[s->aspect_ratio_info];
1321            }
1322        }//MPEG-2
1323
1324        avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1325        avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1326        //until then pix_fmt may be changed right after codec init
1327        if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
1328            avctx->hwaccel ||
1329            s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
1330            if( avctx->idct_algo == FF_IDCT_AUTO )
1331                avctx->idct_algo = FF_IDCT_SIMPLE;
1332
1333        /* Quantization matrices may need reordering
1334         * if DCT permutation is changed. */
1335        memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
1336
1337        if (MPV_common_init(s) < 0)
1338            return -2;
1339
1340        quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
1341        quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
1342        quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
1343        quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
1344
1345        s1->mpeg_enc_ctx_allocated = 1;
1346    }
1347    return 0;
1348}
1349
1350static int mpeg1_decode_picture(AVCodecContext *avctx,
1351                                const uint8_t *buf, int buf_size)
1352{
1353    Mpeg1Context *s1 = avctx->priv_data;
1354    MpegEncContext *s = &s1->mpeg_enc_ctx;
1355    int ref, f_code, vbv_delay;
1356
1357    init_get_bits(&s->gb, buf, buf_size*8);
1358
1359    ref = get_bits(&s->gb, 10); /* temporal ref */
1360    s->pict_type = get_bits(&s->gb, 3);
1361    if(s->pict_type == 0 || s->pict_type > 3)
1362        return -1;
1363
1364    vbv_delay= get_bits(&s->gb, 16);
1365    if (s->pict_type == FF_P_TYPE || s->pict_type == FF_B_TYPE) {
1366        s->full_pel[0] = get_bits1(&s->gb);
1367        f_code = get_bits(&s->gb, 3);
1368        if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1369            return -1;
1370        s->mpeg_f_code[0][0] = f_code;
1371        s->mpeg_f_code[0][1] = f_code;
1372    }
1373    if (s->pict_type == FF_B_TYPE) {
1374        s->full_pel[1] = get_bits1(&s->gb);
1375        f_code = get_bits(&s->gb, 3);
1376        if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1377            return -1;
1378        s->mpeg_f_code[1][0] = f_code;
1379        s->mpeg_f_code[1][1] = f_code;
1380    }
1381    s->current_picture.pict_type= s->pict_type;
1382    s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1383
1384    if(avctx->debug & FF_DEBUG_PICT_INFO)
1385        av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1386
1387    s->y_dc_scale = 8;
1388    s->c_dc_scale = 8;
1389    return 0;
1390}
1391
1392static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1393{
1394    MpegEncContext *s= &s1->mpeg_enc_ctx;
1395    int horiz_size_ext, vert_size_ext;
1396    int bit_rate_ext;
1397
1398    skip_bits(&s->gb, 1); /* profile and level esc*/
1399    s->avctx->profile= get_bits(&s->gb, 3);
1400    s->avctx->level= get_bits(&s->gb, 4);
1401    s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1402    s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1403    horiz_size_ext = get_bits(&s->gb, 2);
1404    vert_size_ext = get_bits(&s->gb, 2);
1405    s->width |= (horiz_size_ext << 12);
1406    s->height |= (vert_size_ext << 12);
1407    bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1408    s->bit_rate += (bit_rate_ext << 18) * 400;
1409    skip_bits1(&s->gb); /* marker */
1410    s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
1411
1412    s->low_delay = get_bits1(&s->gb);
1413    if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
1414
1415    s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
1416    s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
1417
1418    dprintf(s->avctx, "sequence extension\n");
1419    s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
1420    s->avctx->sub_id = 2; /* indicates MPEG-2 found */
1421
1422    if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1423        av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1424               s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1425
1426}
1427
1428static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1429{
1430    MpegEncContext *s= &s1->mpeg_enc_ctx;
1431    int color_description, w, h;
1432
1433    skip_bits(&s->gb, 3); /* video format */
1434    color_description= get_bits1(&s->gb);
1435    if(color_description){
1436        s->avctx->color_primaries= get_bits(&s->gb, 8);
1437        s->avctx->color_trc      = get_bits(&s->gb, 8);
1438        s->avctx->colorspace     = get_bits(&s->gb, 8);
1439    }
1440    w= get_bits(&s->gb, 14);
1441    skip_bits(&s->gb, 1); //marker
1442    h= get_bits(&s->gb, 14);
1443    skip_bits(&s->gb, 1); //marker
1444
1445    s1->pan_scan.width= 16*w;
1446    s1->pan_scan.height=16*h;
1447
1448    if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1449        av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1450}
1451
1452static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1453{
1454    MpegEncContext *s= &s1->mpeg_enc_ctx;
1455    int i,nofco;
1456
1457    nofco = 1;
1458    if(s->progressive_sequence){
1459        if(s->repeat_first_field){
1460            nofco++;
1461            if(s->top_field_first)
1462                nofco++;
1463        }
1464    }else{
1465        if(s->picture_structure == PICT_FRAME){
1466            nofco++;
1467            if(s->repeat_first_field)
1468                nofco++;
1469        }
1470    }
1471    for(i=0; i<nofco; i++){
1472        s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
1473        skip_bits(&s->gb, 1); //marker
1474        s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
1475        skip_bits(&s->gb, 1); //marker
1476    }
1477
1478    if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1479        av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1480            s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1481            s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1482            s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
1483        );
1484}
1485
1486static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra){
1487    int i;
1488
1489    for(i=0; i<64; i++) {
1490        int j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1491        int v = get_bits(&s->gb, 8);
1492        if(v==0){
1493            av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1494            return -1;
1495        }
1496        if(intra && i==0 && v!=8){
1497            av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
1498            v= 8; // needed by pink.mpg / issue1046
1499        }
1500        matrix0[j] = v;
1501        if(matrix1)
1502            matrix1[j] = v;
1503    }
1504    return 0;
1505}
1506
1507static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1508{
1509    dprintf(s->avctx, "matrix extension\n");
1510
1511    if(get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1512    if(get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1513    if(get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
1514    if(get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
1515}
1516
1517static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1518{
1519    MpegEncContext *s= &s1->mpeg_enc_ctx;
1520
1521    s->full_pel[0] = s->full_pel[1] = 0;
1522    s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1523    s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1524    s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1525    s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1526    if(!s->pict_type && s1->mpeg_enc_ctx_allocated){
1527        av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1528        if(s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1]==15){
1529            if(s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1530                s->pict_type= FF_I_TYPE;
1531            else
1532                s->pict_type= FF_P_TYPE;
1533        }else
1534            s->pict_type= FF_B_TYPE;
1535        s->current_picture.pict_type= s->pict_type;
1536        s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1537    }
1538    s->intra_dc_precision = get_bits(&s->gb, 2);
1539    s->picture_structure = get_bits(&s->gb, 2);
1540    s->top_field_first = get_bits1(&s->gb);
1541    s->frame_pred_frame_dct = get_bits1(&s->gb);
1542    s->concealment_motion_vectors = get_bits1(&s->gb);
1543    s->q_scale_type = get_bits1(&s->gb);
1544    s->intra_vlc_format = get_bits1(&s->gb);
1545    s->alternate_scan = get_bits1(&s->gb);
1546    s->repeat_first_field = get_bits1(&s->gb);
1547    s->chroma_420_type = get_bits1(&s->gb);
1548    s->progressive_frame = get_bits1(&s->gb);
1549
1550    if(s->progressive_sequence && !s->progressive_frame){
1551        s->progressive_frame= 1;
1552        av_log(s->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
1553    }
1554
1555    if(s->picture_structure==0 || (s->progressive_frame && s->picture_structure!=PICT_FRAME)){
1556        av_log(s->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s->picture_structure);
1557        s->picture_structure= PICT_FRAME;
1558    }
1559
1560    if(s->progressive_sequence && !s->frame_pred_frame_dct){
1561        av_log(s->avctx, AV_LOG_ERROR, "invalid frame_pred_frame_dct\n");
1562        s->frame_pred_frame_dct= 1;
1563    }
1564
1565    if(s->picture_structure == PICT_FRAME){
1566        s->first_field=0;
1567        s->v_edge_pos= 16*s->mb_height;
1568    }else{
1569        s->first_field ^= 1;
1570        s->v_edge_pos=  8*s->mb_height;
1571        memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1572    }
1573
1574    if(s->alternate_scan){
1575        ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1576        ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1577    }else{
1578        ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1579        ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1580    }
1581
1582    /* composite display not parsed */
1583    dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1584    dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
1585    dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
1586    dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1587    dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1588    dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1589    dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1590    dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1591    dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1592}
1593
1594static void exchange_uv(MpegEncContext *s){
1595    DCTELEM (*tmp)[64];
1596
1597    tmp           = s->pblocks[4];
1598    s->pblocks[4] = s->pblocks[5];
1599    s->pblocks[5] = tmp;
1600}
1601
1602static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size){
1603    AVCodecContext *avctx= s->avctx;
1604    Mpeg1Context *s1 = (Mpeg1Context*)s;
1605
1606    /* start frame decoding */
1607    if(s->first_field || s->picture_structure==PICT_FRAME){
1608        if(MPV_frame_start(s, avctx) < 0)
1609            return -1;
1610
1611        ff_er_frame_start(s);
1612
1613        /* first check if we must repeat the frame */
1614        s->current_picture_ptr->repeat_pict = 0;
1615        if (s->repeat_first_field) {
1616            if (s->progressive_sequence) {
1617                if (s->top_field_first)
1618                    s->current_picture_ptr->repeat_pict = 4;
1619                else
1620                    s->current_picture_ptr->repeat_pict = 2;
1621            } else if (s->progressive_frame) {
1622                s->current_picture_ptr->repeat_pict = 1;
1623            }
1624        }
1625
1626        *s->current_picture_ptr->pan_scan= s1->pan_scan;
1627    }else{ //second field
1628            int i;
1629
1630            if(!s->current_picture_ptr){
1631                av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1632                return -1;
1633            }
1634
1635            for(i=0; i<4; i++){
1636                s->current_picture.data[i] = s->current_picture_ptr->data[i];
1637                if(s->picture_structure == PICT_BOTTOM_FIELD){
1638                    s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1639                }
1640            }
1641    }
1642
1643    if (avctx->hwaccel) {
1644        if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1645            return -1;
1646    }
1647
1648// MPV_frame_start will call this function too,
1649// but we need to call it on every field
1650    if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1651        if(ff_xvmc_field_start(s,avctx) < 0)
1652            return -1;
1653
1654    return 0;
1655}
1656
1657#define DECODE_SLICE_ERROR -1
1658#define DECODE_SLICE_OK 0
1659
1660/**
1661 * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
1662 * @return DECODE_SLICE_ERROR if the slice is damaged<br>
1663 *         DECODE_SLICE_OK if this slice is ok<br>
1664 */
1665static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
1666                             const uint8_t **buf, int buf_size)
1667{
1668    MpegEncContext *s = &s1->mpeg_enc_ctx;
1669    AVCodecContext *avctx= s->avctx;
1670    const int field_pic= s->picture_structure != PICT_FRAME;
1671    const int lowres= s->avctx->lowres;
1672
1673    s->resync_mb_x=
1674    s->resync_mb_y= -1;
1675
1676    assert(mb_y < s->mb_height);
1677
1678    init_get_bits(&s->gb, *buf, buf_size*8);
1679
1680    ff_mpeg1_clean_buffers(s);
1681    s->interlaced_dct = 0;
1682
1683    s->qscale = get_qscale(s);
1684
1685    if(s->qscale == 0){
1686        av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1687        return -1;
1688    }
1689
1690    /* extra slice info */
1691    while (get_bits1(&s->gb) != 0) {
1692        skip_bits(&s->gb, 8);
1693    }
1694
1695    s->mb_x=0;
1696
1697    if(mb_y==0 && s->codec_tag == AV_RL32("SLIF")){
1698        skip_bits1(&s->gb);
1699    }else{
1700        for(;;) {
1701            int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1702            if (code < 0){
1703                av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1704                return -1;
1705            }
1706            if (code >= 33) {
1707                if (code == 33) {
1708                    s->mb_x += 33;
1709                }
1710                /* otherwise, stuffing, nothing to do */
1711            } else {
1712                s->mb_x += code;
1713                break;
1714            }
1715        }
1716    }
1717
1718    if(s->mb_x >= (unsigned)s->mb_width){
1719        av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1720        return -1;
1721    }
1722
1723    if (avctx->hwaccel) {
1724        const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1725        int start_code = -1;
1726        buf_end = ff_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1727        if (buf_end < *buf + buf_size)
1728            buf_end -= 4;
1729        s->mb_y = mb_y;
1730        if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1731            return DECODE_SLICE_ERROR;
1732        *buf = buf_end;
1733        return DECODE_SLICE_OK;
1734    }
1735
1736    s->resync_mb_x= s->mb_x;
1737    s->resync_mb_y= s->mb_y= mb_y;
1738    s->mb_skip_run= 0;
1739    ff_init_block_index(s);
1740
1741    if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
1742        if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1743             av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%2d%2d%2d%2d %s %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n",
1744                 s->qscale, s->mpeg_f_code[0][0],s->mpeg_f_code[0][1],s->mpeg_f_code[1][0],s->mpeg_f_code[1][1],
1745                 s->pict_type == FF_I_TYPE ? "I" : (s->pict_type == FF_P_TYPE ? "P" : (s->pict_type == FF_B_TYPE ? "B" : "S")),
1746                 s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1747                 s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1748                 s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1749        }
1750    }
1751
1752    for(;;) {
1753        //If 1, we memcpy blocks in xvmcvideo.
1754        if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1755            ff_xvmc_init_block(s);//set s->block
1756
1757        if(mpeg_decode_mb(s, s->block) < 0)
1758            return -1;
1759
1760        if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
1761            const int wrap = s->b8_stride;
1762            int xy = s->mb_x*2 + s->mb_y*2*wrap;
1763            int b8_xy= 4*(s->mb_x + s->mb_y*s->mb_stride);
1764            int motion_x, motion_y, dir, i;
1765
1766            for(i=0; i<2; i++){
1767                for(dir=0; dir<2; dir++){
1768                    if (s->mb_intra || (dir==1 && s->pict_type != FF_B_TYPE)) {
1769                        motion_x = motion_y = 0;
1770                    }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
1771                        motion_x = s->mv[dir][0][0];
1772                        motion_y = s->mv[dir][0][1];
1773                    } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1774                        motion_x = s->mv[dir][i][0];
1775                        motion_y = s->mv[dir][i][1];
1776                    }
1777
1778                    s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1779                    s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1780                    s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1781                    s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1782                    s->current_picture.ref_index [dir][b8_xy    ]=
1783                    s->current_picture.ref_index [dir][b8_xy + 1]= s->field_select[dir][i];
1784                    assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
1785                }
1786                xy += wrap;
1787                b8_xy +=2;
1788            }
1789        }
1790
1791        s->dest[0] += 16 >> lowres;
1792        s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1793        s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1794
1795        MPV_decode_mb(s, s->block);
1796
1797        if (++s->mb_x >= s->mb_width) {
1798            const int mb_size= 16>>s->avctx->lowres;
1799
1800            ff_draw_horiz_band(s, mb_size*(s->mb_y>>field_pic), mb_size);
1801
1802            s->mb_x = 0;
1803            s->mb_y += 1<<field_pic;
1804
1805            if(s->mb_y >= s->mb_height){
1806                int left= get_bits_left(&s->gb);
1807                int is_d10= s->chroma_format==2 && s->pict_type==FF_I_TYPE && avctx->profile==0 && avctx->level==5
1808                            && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1809                            && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1810
1811                if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1812                   || (avctx->error_recognition >= FF_ER_AGGRESSIVE && left>8)){
1813                    av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1814                    return -1;
1815                }else
1816                    goto eos;
1817            }
1818
1819            ff_init_block_index(s);
1820        }
1821
1822        /* skip mb handling */
1823        if (s->mb_skip_run == -1) {
1824            /* read increment again */
1825            s->mb_skip_run = 0;
1826            for(;;) {
1827                int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1828                if (code < 0){
1829                    av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1830                    return -1;
1831                }
1832                if (code >= 33) {
1833                    if (code == 33) {
1834                        s->mb_skip_run += 33;
1835                    }else if(code == 35){
1836                        if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1837                            av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1838                            return -1;
1839                        }
1840                        goto eos; /* end of slice */
1841                    }
1842                    /* otherwise, stuffing, nothing to do */
1843                } else {
1844                    s->mb_skip_run += code;
1845                    break;
1846                }
1847            }
1848            if(s->mb_skip_run){
1849                int i;
1850                if(s->pict_type == FF_I_TYPE){
1851                    av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1852                    return -1;
1853                }
1854
1855                /* skip mb */
1856                s->mb_intra = 0;
1857                for(i=0;i<12;i++)
1858                    s->block_last_index[i] = -1;
1859                if(s->picture_structure == PICT_FRAME)
1860                    s->mv_type = MV_TYPE_16X16;
1861                else
1862                    s->mv_type = MV_TYPE_FIELD;
1863                if (s->pict_type == FF_P_TYPE) {
1864                    /* if P type, zero motion vector is implied */
1865                    s->mv_dir = MV_DIR_FORWARD;
1866                    s->mv[0][0][0] = s->mv[0][0][1] = 0;
1867                    s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1868                    s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1869                    s->field_select[0][0]= (s->picture_structure - 1) & 1;
1870                } else {
1871                    /* if B type, reuse previous vectors and directions */
1872                    s->mv[0][0][0] = s->last_mv[0][0][0];
1873                    s->mv[0][0][1] = s->last_mv[0][0][1];
1874                    s->mv[1][0][0] = s->last_mv[1][0][0];
1875                    s->mv[1][0][1] = s->last_mv[1][0][1];
1876                }
1877            }
1878        }
1879    }
1880eos: // end of slice
1881    *buf += (get_bits_count(&s->gb)-1)/8;
1882//printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1883    return 0;
1884}
1885
1886static int slice_decode_thread(AVCodecContext *c, void *arg){
1887    MpegEncContext *s= *(void**)arg;
1888    const uint8_t *buf= s->gb.buffer;
1889    int mb_y= s->start_mb_y;
1890    const int field_pic= s->picture_structure != PICT_FRAME;
1891
1892    s->error_count= (3*(s->end_mb_y - s->start_mb_y)*s->mb_width) >> field_pic;
1893
1894    for(;;){
1895        uint32_t start_code;
1896        int ret;
1897
1898        ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
1899        emms_c();
1900//av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1901//ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, s->start_mb_y, s->end_mb_y, s->error_count);
1902        if(ret < 0){
1903            if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
1904                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);
1905        }else{
1906            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);
1907        }
1908
1909        if(s->mb_y == s->end_mb_y)
1910            return 0;
1911
1912        start_code= -1;
1913        buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
1914        mb_y= start_code - SLICE_MIN_START_CODE;
1915        if(mb_y < 0 || mb_y >= s->end_mb_y)
1916            return -1;
1917    }
1918
1919    return 0; //not reached
1920}
1921
1922/**
1923 * Handles slice ends.
1924 * @return 1 if it seems to be the last slice
1925 */
1926static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1927{
1928    Mpeg1Context *s1 = avctx->priv_data;
1929    MpegEncContext *s = &s1->mpeg_enc_ctx;
1930
1931    if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1932        return 0;
1933
1934    if (s->avctx->hwaccel) {
1935        if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1936            av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
1937    }
1938
1939    if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1940        ff_xvmc_field_end(s);
1941
1942    /* end of slice reached */
1943    if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1944        /* end of image */
1945
1946        s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1947
1948        ff_er_frame_end(s);
1949
1950        MPV_frame_end(s);
1951
1952        if (s->pict_type == FF_B_TYPE || s->low_delay) {
1953            *pict= *(AVFrame*)s->current_picture_ptr;
1954            ff_print_debug_info(s, pict);
1955        } else {
1956            s->picture_number++;
1957            /* latency of 1 frame for I- and P-frames */
1958            /* XXX: use another variable than picture_number */
1959            if (s->last_picture_ptr != NULL) {
1960                *pict= *(AVFrame*)s->last_picture_ptr;
1961                 ff_print_debug_info(s, pict);
1962            }
1963        }
1964
1965        return 1;
1966    } else {
1967        return 0;
1968    }
1969}
1970
1971static int mpeg1_decode_sequence(AVCodecContext *avctx,
1972                                 const uint8_t *buf, int buf_size)
1973{
1974    Mpeg1Context *s1 = avctx->priv_data;
1975    MpegEncContext *s = &s1->mpeg_enc_ctx;
1976    int width,height;
1977    int i, v, j;
1978
1979    init_get_bits(&s->gb, buf, buf_size*8);
1980
1981    width = get_bits(&s->gb, 12);
1982    height = get_bits(&s->gb, 12);
1983    if (width <= 0 || height <= 0)
1984        return -1;
1985    s->aspect_ratio_info= get_bits(&s->gb, 4);
1986    if (s->aspect_ratio_info == 0) {
1987        av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1988        if (avctx->error_recognition >= FF_ER_COMPLIANT)
1989            return -1;
1990    }
1991    s->frame_rate_index = get_bits(&s->gb, 4);
1992    if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1993        return -1;
1994    s->bit_rate = get_bits(&s->gb, 18) * 400;
1995    if (get_bits1(&s->gb) == 0) /* marker */
1996        return -1;
1997    s->width = width;
1998    s->height = height;
1999
2000    s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
2001    skip_bits(&s->gb, 1);
2002
2003    /* get matrix */
2004    if (get_bits1(&s->gb)) {
2005        load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2006    } else {
2007        for(i=0;i<64;i++) {
2008            j = s->dsp.idct_permutation[i];
2009            v = ff_mpeg1_default_intra_matrix[i];
2010            s->intra_matrix[j] = v;
2011            s->chroma_intra_matrix[j] = v;
2012        }
2013    }
2014    if (get_bits1(&s->gb)) {
2015        load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2016    } else {
2017        for(i=0;i<64;i++) {
2018            int j= s->dsp.idct_permutation[i];
2019            v = ff_mpeg1_default_non_intra_matrix[i];
2020            s->inter_matrix[j] = v;
2021            s->chroma_inter_matrix[j] = v;
2022        }
2023    }
2024
2025    if(show_bits(&s->gb, 23) != 0){
2026        av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2027        return -1;
2028    }
2029
2030    /* we set MPEG-2 parameters so that it emulates MPEG-1 */
2031    s->progressive_sequence = 1;
2032    s->progressive_frame = 1;
2033    s->picture_structure = PICT_FRAME;
2034    s->frame_pred_frame_dct = 1;
2035    s->chroma_format = 1;
2036    s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2037    avctx->sub_id = 1; /* indicates MPEG-1 */
2038    s->out_format = FMT_MPEG1;
2039    s->swap_uv = 0;//AFAIK VCR2 does not have SEQ_HEADER
2040    if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2041
2042    if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2043        av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2044               s->avctx->rc_buffer_size, s->bit_rate);
2045
2046    return 0;
2047}
2048
2049static int vcr2_init_sequence(AVCodecContext *avctx)
2050{
2051    Mpeg1Context *s1 = avctx->priv_data;
2052    MpegEncContext *s = &s1->mpeg_enc_ctx;
2053    int i, v;
2054
2055    /* start new MPEG-1 context decoding */
2056    s->out_format = FMT_MPEG1;
2057    if (s1->mpeg_enc_ctx_allocated) {
2058        MPV_common_end(s);
2059    }
2060    s->width  = avctx->coded_width;
2061    s->height = avctx->coded_height;
2062    avctx->has_b_frames= 0; //true?
2063    s->low_delay= 1;
2064
2065    avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2066    avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
2067
2068    if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
2069        s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
2070        if( avctx->idct_algo == FF_IDCT_AUTO )
2071            avctx->idct_algo = FF_IDCT_SIMPLE;
2072
2073    if (MPV_common_init(s) < 0)
2074        return -1;
2075    exchange_uv(s);//common init reset pblocks, so we swap them here
2076    s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
2077    s1->mpeg_enc_ctx_allocated = 1;
2078
2079    for(i=0;i<64;i++) {
2080        int j= s->dsp.idct_permutation[i];
2081        v = ff_mpeg1_default_intra_matrix[i];
2082        s->intra_matrix[j] = v;
2083        s->chroma_intra_matrix[j] = v;
2084
2085        v = ff_mpeg1_default_non_intra_matrix[i];
2086        s->inter_matrix[j] = v;
2087        s->chroma_inter_matrix[j] = v;
2088    }
2089
2090    s->progressive_sequence = 1;
2091    s->progressive_frame = 1;
2092    s->picture_structure = PICT_FRAME;
2093    s->frame_pred_frame_dct = 1;
2094    s->chroma_format = 1;
2095    s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2096    avctx->sub_id = 2; /* indicates MPEG-2 */
2097    s1->save_width           = s->width;
2098    s1->save_height          = s->height;
2099    s1->save_progressive_seq = s->progressive_sequence;
2100    return 0;
2101}
2102
2103
2104static void mpeg_decode_user_data(AVCodecContext *avctx,
2105                                  const uint8_t *p, int buf_size)
2106{
2107    const uint8_t *buf_end = p+buf_size;
2108
2109    /* we parse the DTG active format information */
2110    if (buf_end - p >= 5 &&
2111        p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2112        int flags = p[4];
2113        p += 5;
2114        if (flags & 0x80) {
2115            /* skip event id */
2116            p += 2;
2117        }
2118        if (flags & 0x40) {
2119            if (buf_end - p < 1)
2120                return;
2121            avctx->dtg_active_format = p[0] & 0x0f;
2122        }
2123    }
2124}
2125
2126static void mpeg_decode_gop(AVCodecContext *avctx,
2127                            const uint8_t *buf, int buf_size){
2128    Mpeg1Context *s1 = avctx->priv_data;
2129    MpegEncContext *s = &s1->mpeg_enc_ctx;
2130
2131    int drop_frame_flag;
2132    int time_code_hours, time_code_minutes;
2133    int time_code_seconds, time_code_pictures;
2134    int broken_link;
2135
2136    init_get_bits(&s->gb, buf, buf_size*8);
2137
2138    drop_frame_flag = get_bits1(&s->gb);
2139
2140    time_code_hours=get_bits(&s->gb,5);
2141    time_code_minutes = get_bits(&s->gb,6);
2142    skip_bits1(&s->gb);//marker bit
2143    time_code_seconds = get_bits(&s->gb,6);
2144    time_code_pictures = get_bits(&s->gb,6);
2145
2146    s->closed_gop = get_bits1(&s->gb);
2147    /*broken_link indicate that after editing the
2148      reference frames of the first B-Frames after GOP I-Frame
2149      are missing (open gop)*/
2150    broken_link = get_bits1(&s->gb);
2151
2152    if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2153        av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2154            time_code_hours, time_code_minutes, time_code_seconds,
2155            time_code_pictures, s->closed_gop, broken_link);
2156}
2157/**
2158 * Finds the end of the current frame in the bitstream.
2159 * @return the position of the first byte of the next frame, or -1
2160 */
2161int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
2162{
2163    int i;
2164    uint32_t state= pc->state;
2165
2166    /* EOF considered as end of frame */
2167    if (buf_size == 0)
2168        return 0;
2169
2170/*
2171 0  frame start         -> 1/4
2172 1  first_SEQEXT        -> 0/2
2173 2  first field start   -> 3/0
2174 3  second_SEQEXT       -> 2/0
2175 4  searching end
2176*/
2177
2178    for(i=0; i<buf_size; i++){
2179        assert(pc->frame_start_found>=0 && pc->frame_start_found<=4);
2180        if(pc->frame_start_found&1){
2181            if(state == EXT_START_CODE && (buf[i]&0xF0) != 0x80)
2182                pc->frame_start_found--;
2183            else if(state == EXT_START_CODE+2){
2184                if((buf[i]&3) == 3) pc->frame_start_found= 0;
2185                else                pc->frame_start_found= (pc->frame_start_found+1)&3;
2186            }
2187            state++;
2188        }else{
2189            i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2190            if(pc->frame_start_found==0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2191                i++;
2192                pc->frame_start_found=4;
2193            }
2194            if(state == SEQ_END_CODE){
2195                pc->state=-1;
2196                return i+1;
2197            }
2198            if(pc->frame_start_found==2 && state == SEQ_START_CODE)
2199                pc->frame_start_found= 0;
2200            if(pc->frame_start_found<4 && state == EXT_START_CODE)
2201                pc->frame_start_found++;
2202            if(pc->frame_start_found == 4 && (state&0xFFFFFF00) == 0x100){
2203                if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2204                    pc->frame_start_found=0;
2205                    pc->state=-1;
2206                    return i-3;
2207                }
2208            }
2209            if(pc->frame_start_found == 0 && s && state == PICTURE_START_CODE){
2210                ff_fetch_timestamp(s, i-3, 1);
2211            }
2212        }
2213    }
2214    pc->state= state;
2215    return END_NOT_FOUND;
2216}
2217
2218static int decode_chunks(AVCodecContext *avctx,
2219                             AVFrame *picture, int *data_size,
2220                             const uint8_t *buf, int buf_size);
2221
2222/* handle buffering and image synchronisation */
2223static int mpeg_decode_frame(AVCodecContext *avctx,
2224                             void *data, int *data_size,
2225                             AVPacket *avpkt)
2226{
2227    const uint8_t *buf = avpkt->data;
2228    int buf_size = avpkt->size;
2229    Mpeg1Context *s = avctx->priv_data;
2230    AVFrame *picture = data;
2231    MpegEncContext *s2 = &s->mpeg_enc_ctx;
2232    dprintf(avctx, "fill_buffer\n");
2233
2234    if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2235        /* special case for last picture */
2236        if (s2->low_delay==0 && s2->next_picture_ptr) {
2237            *picture= *(AVFrame*)s2->next_picture_ptr;
2238            s2->next_picture_ptr= NULL;
2239
2240            *data_size = sizeof(AVFrame);
2241        }
2242        return buf_size;
2243    }
2244
2245    if(s2->flags&CODEC_FLAG_TRUNCATED){
2246        int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
2247
2248        if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
2249            return buf_size;
2250    }
2251
2252#if 0
2253    if (s->repeat_field % 2 == 1) {
2254        s->repeat_field++;
2255        //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2256        //        s2->picture_number, s->repeat_field);
2257        if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2258            *data_size = sizeof(AVPicture);
2259            goto the_end;
2260        }
2261    }
2262#endif
2263
2264    if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == AV_RL32("VCR2"))
2265        vcr2_init_sequence(avctx);
2266
2267    s->slice_count= 0;
2268
2269    if(avctx->extradata && !avctx->frame_number)
2270        decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
2271
2272    return decode_chunks(avctx, picture, data_size, buf, buf_size);
2273}
2274
2275static int decode_chunks(AVCodecContext *avctx,
2276                             AVFrame *picture, int *data_size,
2277                             const uint8_t *buf, int buf_size)
2278{
2279    Mpeg1Context *s = avctx->priv_data;
2280    MpegEncContext *s2 = &s->mpeg_enc_ctx;
2281    const uint8_t *buf_ptr = buf;
2282    const uint8_t *buf_end = buf + buf_size;
2283    int ret, input_size;
2284    int last_code= 0;
2285
2286    for(;;) {
2287        /* find next start code */
2288        uint32_t start_code = -1;
2289        buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
2290        if (start_code > 0x1ff){
2291            if(s2->pict_type != FF_B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
2292                if(avctx->thread_count > 1){
2293                    int i;
2294
2295                    avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
2296                    for(i=0; i<s->slice_count; i++)
2297                        s2->error_count += s2->thread_context[i]->error_count;
2298                }
2299
2300                if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
2301                    ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2302
2303                if (slice_end(avctx, picture)) {
2304                    if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2305                        *data_size = sizeof(AVPicture);
2306                }
2307            }
2308            s2->pict_type= 0;
2309            return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2310        }
2311
2312        input_size = buf_end - buf_ptr;
2313
2314        if(avctx->debug & FF_DEBUG_STARTCODE){
2315            av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2316        }
2317
2318        /* prepare data for next start code */
2319        switch(start_code) {
2320        case SEQ_START_CODE:
2321            if(last_code == 0){
2322            mpeg1_decode_sequence(avctx, buf_ptr,
2323                                    input_size);
2324                s->sync=1;
2325            }else{
2326                av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
2327            }
2328            break;
2329
2330        case PICTURE_START_CODE:
2331            if(last_code == 0 || last_code == SLICE_MIN_START_CODE){
2332            if(mpeg_decode_postinit(avctx) < 0){
2333                av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
2334                return -1;
2335            }
2336
2337            /* we have a complete image: we try to decompress it */
2338            if(mpeg1_decode_picture(avctx,
2339                                    buf_ptr, input_size) < 0)
2340                s2->pict_type=0;
2341                s2->first_slice = 1;
2342            last_code= PICTURE_START_CODE;
2343            }else{
2344                av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
2345            }
2346            break;
2347        case EXT_START_CODE:
2348            init_get_bits(&s2->gb, buf_ptr, input_size*8);
2349
2350            switch(get_bits(&s2->gb, 4)) {
2351            case 0x1:
2352                if(last_code == 0){
2353                mpeg_decode_sequence_extension(s);
2354                }else{
2355                    av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
2356                }
2357                break;
2358            case 0x2:
2359                mpeg_decode_sequence_display_extension(s);
2360                break;
2361            case 0x3:
2362                mpeg_decode_quant_matrix_extension(s2);
2363                break;
2364            case 0x7:
2365                mpeg_decode_picture_display_extension(s);
2366                break;
2367            case 0x8:
2368                if(last_code == PICTURE_START_CODE){
2369                mpeg_decode_picture_coding_extension(s);
2370                }else{
2371                    av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
2372                }
2373                break;
2374            }
2375            break;
2376        case USER_START_CODE:
2377            mpeg_decode_user_data(avctx,
2378                                    buf_ptr, input_size);
2379            break;
2380        case GOP_START_CODE:
2381            if(last_code == 0){
2382            s2->first_field=0;
2383            mpeg_decode_gop(avctx,
2384                                    buf_ptr, input_size);
2385                s->sync=1;
2386            }else{
2387                av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
2388            }
2389            break;
2390        default:
2391            if (start_code >= SLICE_MIN_START_CODE &&
2392                start_code <= SLICE_MAX_START_CODE && last_code!=0) {
2393                const int field_pic= s2->picture_structure != PICT_FRAME;
2394                int mb_y= (start_code - SLICE_MIN_START_CODE) << field_pic;
2395                last_code= SLICE_MIN_START_CODE;
2396
2397                if(s2->picture_structure == PICT_BOTTOM_FIELD)
2398                    mb_y++;
2399
2400                if (mb_y >= s2->mb_height){
2401                    av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2402                    return -1;
2403                }
2404
2405                if(s2->last_picture_ptr==NULL){
2406                /* Skip B-frames if we do not have reference frames and gop is not closed */
2407                    if(s2->pict_type==FF_B_TYPE){
2408                        if(!s2->closed_gop)
2409                            break;
2410                    }
2411                }
2412                if(s2->pict_type==FF_I_TYPE)
2413                    s->sync=1;
2414                if(s2->next_picture_ptr==NULL){
2415                /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
2416                    if(s2->pict_type==FF_P_TYPE && !s->sync) break;
2417                }
2418                /* Skip B-frames if we are in a hurry. */
2419                if(avctx->hurry_up && s2->pict_type==FF_B_TYPE) break;
2420                if(  (avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type==FF_B_TYPE)
2421                    ||(avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type!=FF_I_TYPE)
2422                    || avctx->skip_frame >= AVDISCARD_ALL)
2423                    break;
2424                /* Skip everything if we are in a hurry>=5. */
2425                if(avctx->hurry_up>=5) break;
2426
2427                if (!s->mpeg_enc_ctx_allocated) break;
2428
2429                if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
2430                    if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2431                        break;
2432                }
2433
2434                if(!s2->pict_type){
2435                    av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2436                    break;
2437                }
2438
2439                if(s2->first_slice){
2440                    s2->first_slice=0;
2441                    if(mpeg_field_start(s2, buf, buf_size) < 0)
2442                        return -1;
2443                }
2444                if(!s2->current_picture_ptr){
2445                    av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2446                    return -1;
2447                }
2448
2449                if (avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU) {
2450                    s->slice_count++;
2451                    break;
2452                }
2453
2454                if(avctx->thread_count > 1){
2455                    int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
2456                    if(threshold <= mb_y){
2457                        MpegEncContext *thread_context= s2->thread_context[s->slice_count];
2458
2459                        thread_context->start_mb_y= mb_y;
2460                        thread_context->end_mb_y  = s2->mb_height;
2461                        if(s->slice_count){
2462                            s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
2463                            ff_update_duplicate_context(thread_context, s2);
2464                        }
2465                        init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2466                        s->slice_count++;
2467                    }
2468                    buf_ptr += 2; //FIXME add minimum number of bytes per slice
2469                }else{
2470                    ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
2471                    emms_c();
2472
2473                    if(ret < 0){
2474                        if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2475                            ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x, s2->mb_y, AC_ERROR|DC_ERROR|MV_ERROR);
2476                    }else{
2477                        ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x-1, s2->mb_y, AC_END|DC_END|MV_END);
2478                    }
2479                }
2480            }
2481            break;
2482        }
2483    }
2484}
2485
2486static void flush(AVCodecContext *avctx){
2487    Mpeg1Context *s = avctx->priv_data;
2488
2489    s->sync=0;
2490
2491    ff_mpeg_flush(avctx);
2492}
2493
2494static int mpeg_decode_end(AVCodecContext *avctx)
2495{
2496    Mpeg1Context *s = avctx->priv_data;
2497
2498    if (s->mpeg_enc_ctx_allocated)
2499        MPV_common_end(&s->mpeg_enc_ctx);
2500    return 0;
2501}
2502
2503AVCodec mpeg1video_decoder = {
2504    "mpeg1video",
2505    AVMEDIA_TYPE_VIDEO,
2506    CODEC_ID_MPEG1VIDEO,
2507    sizeof(Mpeg1Context),
2508    mpeg_decode_init,
2509    NULL,
2510    mpeg_decode_end,
2511    mpeg_decode_frame,
2512    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2513    .flush= flush,
2514    .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2515};
2516
2517AVCodec mpeg2video_decoder = {
2518    "mpeg2video",
2519    AVMEDIA_TYPE_VIDEO,
2520    CODEC_ID_MPEG2VIDEO,
2521    sizeof(Mpeg1Context),
2522    mpeg_decode_init,
2523    NULL,
2524    mpeg_decode_end,
2525    mpeg_decode_frame,
2526    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2527    .flush= flush,
2528    .long_name= NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2529};
2530
2531//legacy decoder
2532AVCodec mpegvideo_decoder = {
2533    "mpegvideo",
2534    AVMEDIA_TYPE_VIDEO,
2535    CODEC_ID_MPEG2VIDEO,
2536    sizeof(Mpeg1Context),
2537    mpeg_decode_init,
2538    NULL,
2539    mpeg_decode_end,
2540    mpeg_decode_frame,
2541    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2542    .flush= flush,
2543    .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2544};
2545
2546#if CONFIG_MPEG_XVMC_DECODER
2547static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx){
2548    if( avctx->thread_count > 1)
2549        return -1;
2550    if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
2551        return -1;
2552    if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
2553        dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2554    }
2555    mpeg_decode_init(avctx);
2556
2557    avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
2558    avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
2559
2560    return 0;
2561}
2562
2563AVCodec mpeg_xvmc_decoder = {
2564    "mpegvideo_xvmc",
2565    AVMEDIA_TYPE_VIDEO,
2566    CODEC_ID_MPEG2VIDEO_XVMC,
2567    sizeof(Mpeg1Context),
2568    mpeg_mc_decode_init,
2569    NULL,
2570    mpeg_decode_end,
2571    mpeg_decode_frame,
2572    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2573    .flush= flush,
2574    .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2575};
2576
2577#endif
2578
2579#if CONFIG_MPEG_VDPAU_DECODER
2580AVCodec mpeg_vdpau_decoder = {
2581    "mpegvideo_vdpau",
2582    AVMEDIA_TYPE_VIDEO,
2583    CODEC_ID_MPEG2VIDEO,
2584    sizeof(Mpeg1Context),
2585    mpeg_decode_init,
2586    NULL,
2587    mpeg_decode_end,
2588    mpeg_decode_frame,
2589    CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2590    .flush= flush,
2591    .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2592};
2593#endif
2594
2595#if CONFIG_MPEG1_VDPAU_DECODER
2596AVCodec mpeg1_vdpau_decoder = {
2597    "mpeg1video_vdpau",
2598    AVMEDIA_TYPE_VIDEO,
2599    CODEC_ID_MPEG1VIDEO,
2600    sizeof(Mpeg1Context),
2601    mpeg_decode_init,
2602    NULL,
2603    mpeg_decode_end,
2604    mpeg_decode_frame,
2605    CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2606    .flush= flush,
2607    .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2608};
2609#endif
2610
2611