avoid 2 additions (1 cpu cycle) per MB
[ffmpeg.git] / libavcodec / mpeg12.c
1 /*
2  * MPEG1/2 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 mpeg12.c
25  * MPEG1/2 decoder
26  */
27
28 //#define DEBUG
29 #include "avcodec.h"
30 #include "dsputil.h"
31 #include "mpegvideo.h"
32
33 #include "mpeg12.h"
34 #include "mpeg12data.h"
35 #include "mpeg12decdata.h"
36 #include "bytestream.h"
37
38 //#undef NDEBUG
39 //#include <assert.h>
40
41
42 #define DC_VLC_BITS 9
43 #define MV_VLC_BITS 9
44 #define MBINCR_VLC_BITS 9
45 #define MB_PAT_VLC_BITS 9
46 #define MB_PTYPE_VLC_BITS 6
47 #define MB_BTYPE_VLC_BITS 6
48 #define TEX_VLC_BITS 9
49
50 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
51                               DCTELEM *block,
52                               int n);
53 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
54                               DCTELEM *block,
55                               int n);
56 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
57 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
58                                         DCTELEM *block,
59                                         int n);
60 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
61                                     DCTELEM *block,
62                                     int n);
63 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
64 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
65 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
66 static void exchange_uv(MpegEncContext *s);
67
68 extern int XVMC_field_start(MpegEncContext *s, AVCodecContext *avctx);
69 extern int XVMC_field_end(MpegEncContext *s);
70 extern void XVMC_pack_pblocks(MpegEncContext *s,int cbp);
71 extern void XVMC_init_block(MpegEncContext *s);//set s->block
72
73 static const enum PixelFormat pixfmt_yuv_420[]= {PIX_FMT_YUV420P,-1};
74 static const enum PixelFormat pixfmt_yuv_422[]= {PIX_FMT_YUV422P,-1};
75 static const enum PixelFormat pixfmt_yuv_444[]= {PIX_FMT_YUV444P,-1};
76 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
77                                            PIX_FMT_XVMC_MPEG2_IDCT,
78                                            PIX_FMT_XVMC_MPEG2_MC,
79                                            -1};
80
81 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
82
83 static void init_2d_vlc_rl(RLTable *rl, int use_static)
84 {
85     int i;
86
87     init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2,
88              &rl->table_vlc[0][1], 4, 2,
89              &rl->table_vlc[0][0], 4, 2, use_static);
90
91     if(use_static)
92         rl->rl_vlc[0]= av_mallocz_static(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
93     else
94         rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
95
96     for(i=0; i<rl->vlc.table_size; i++){
97         int code= rl->vlc.table[i][0];
98         int len = rl->vlc.table[i][1];
99         int level, run;
100
101         if(len==0){ // illegal code
102             run= 65;
103             level= MAX_LEVEL;
104         }else if(len<0){ //more bits needed
105             run= 0;
106             level= code;
107         }else{
108             if(code==rl->n){ //esc
109                 run= 65;
110                 level= 0;
111             }else if(code==rl->n+1){ //eob
112                 run= 0;
113                 level= 127;
114             }else{
115                 run=   rl->table_run  [code] + 1;
116                 level= rl->table_level[code];
117             }
118         }
119         rl->rl_vlc[0][i].len= len;
120         rl->rl_vlc[0][i].level= level;
121         rl->rl_vlc[0][i].run= run;
122     }
123 }
124
125 void ff_mpeg12_common_init(MpegEncContext *s)
126 {
127
128     s->y_dc_scale_table=
129     s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
130
131 }
132
133 void ff_mpeg1_clean_buffers(MpegEncContext *s){
134     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
135     s->last_dc[1] = s->last_dc[0];
136     s->last_dc[2] = s->last_dc[0];
137     memset(s->last_mv, 0, sizeof(s->last_mv));
138 }
139
140
141 /******************************************/
142 /* decoding */
143
144 static VLC dc_lum_vlc;
145 static VLC dc_chroma_vlc;
146 static VLC mv_vlc;
147 static VLC mbincr_vlc;
148 static VLC mb_ptype_vlc;
149 static VLC mb_btype_vlc;
150 static VLC mb_pat_vlc;
151
152 static void init_vlcs(void)
153 {
154     static int done = 0;
155
156     if (!done) {
157         done = 1;
158
159         init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12,
160                  ff_mpeg12_vlc_dc_lum_bits, 1, 1,
161                  ff_mpeg12_vlc_dc_lum_code, 2, 2, 1);
162         init_vlc(&dc_chroma_vlc,  DC_VLC_BITS, 12,
163                  ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
164                  ff_mpeg12_vlc_dc_chroma_code, 2, 2, 1);
165         init_vlc(&mv_vlc, MV_VLC_BITS, 17,
166                  &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
167                  &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 1);
168         init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36,
169                  &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
170                  &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 1);
171         init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
172                  &ff_mpeg12_mbPatTable[0][1], 2, 1,
173                  &ff_mpeg12_mbPatTable[0][0], 2, 1, 1);
174
175         init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
176                  &table_mb_ptype[0][1], 2, 1,
177                  &table_mb_ptype[0][0], 2, 1, 1);
178         init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
179                  &table_mb_btype[0][1], 2, 1,
180                  &table_mb_btype[0][0], 2, 1, 1);
181         init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
182         init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
183
184         init_2d_vlc_rl(&ff_rl_mpeg1, 1);
185         init_2d_vlc_rl(&ff_rl_mpeg2, 1);
186     }
187 }
188
189 static inline int get_dmv(MpegEncContext *s)
190 {
191     if(get_bits1(&s->gb))
192         return 1 - (get_bits1(&s->gb) << 1);
193     else
194         return 0;
195 }
196
197 static inline int get_qscale(MpegEncContext *s)
198 {
199     int qscale = get_bits(&s->gb, 5);
200     if (s->q_scale_type) {
201         return non_linear_qscale[qscale];
202     } else {
203         return qscale << 1;
204     }
205 }
206
207 /* motion type (for mpeg2) */
208 #define MT_FIELD 1
209 #define MT_FRAME 2
210 #define MT_16X8  2
211 #define MT_DMV   3
212
213 static int mpeg_decode_mb(MpegEncContext *s,
214                           DCTELEM block[12][64])
215 {
216     int i, j, k, cbp, val, mb_type, motion_type;
217     const int mb_block_count = 4 + (1<< s->chroma_format);
218
219     dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
220
221     assert(s->mb_skipped==0);
222
223     if (s->mb_skip_run-- != 0) {
224         if(s->pict_type == I_TYPE){
225             av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
226             return -1;
227         }
228
229         /* skip mb */
230         s->mb_intra = 0;
231         for(i=0;i<12;i++)
232             s->block_last_index[i] = -1;
233         if(s->picture_structure == PICT_FRAME)
234             s->mv_type = MV_TYPE_16X16;
235         else
236             s->mv_type = MV_TYPE_FIELD;
237         if (s->pict_type == P_TYPE) {
238             /* if P type, zero motion vector is implied */
239             s->mv_dir = MV_DIR_FORWARD;
240             s->mv[0][0][0] = s->mv[0][0][1] = 0;
241             s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
242             s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
243             s->field_select[0][0]= s->picture_structure - 1;
244             s->mb_skipped = 1;
245             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
246         } else {
247             int mb_type;
248
249             if(s->mb_x)
250                 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
251             else
252                 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,
253             if(IS_INTRA(mb_type))
254                 return -1;
255
256             /* if B type, reuse previous vectors and directions */
257             s->mv[0][0][0] = s->last_mv[0][0][0];
258             s->mv[0][0][1] = s->last_mv[0][0][1];
259             s->mv[1][0][0] = s->last_mv[1][0][0];
260             s->mv[1][0][1] = s->last_mv[1][0][1];
261
262             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
263                 mb_type | MB_TYPE_SKIP;
264 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
265
266             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
267                 s->mb_skipped = 1;
268         }
269
270         return 0;
271     }
272
273     switch(s->pict_type) {
274     default:
275     case I_TYPE:
276         if (get_bits1(&s->gb) == 0) {
277             if (get_bits1(&s->gb) == 0){
278                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
279                 return -1;
280             }
281             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
282         } else {
283             mb_type = MB_TYPE_INTRA;
284         }
285         break;
286     case P_TYPE:
287         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
288         if (mb_type < 0){
289             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
290             return -1;
291         }
292         mb_type = ptype2mb_type[ mb_type ];
293         break;
294     case B_TYPE:
295         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
296         if (mb_type < 0){
297             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
298             return -1;
299         }
300         mb_type = btype2mb_type[ mb_type ];
301         break;
302     }
303     dprintf(s->avctx, "mb_type=%x\n", mb_type);
304 //    motion_type = 0; /* avoid warning */
305     if (IS_INTRA(mb_type)) {
306         s->dsp.clear_blocks(s->block[0]);
307
308         if(!s->chroma_y_shift){
309             s->dsp.clear_blocks(s->block[6]);
310         }
311
312         /* compute dct type */
313         if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
314             !s->frame_pred_frame_dct) {
315             s->interlaced_dct = get_bits1(&s->gb);
316         }
317
318         if (IS_QUANT(mb_type))
319             s->qscale = get_qscale(s);
320
321         if (s->concealment_motion_vectors) {
322             /* just parse them */
323             if (s->picture_structure != PICT_FRAME)
324                 skip_bits1(&s->gb); /* field select */
325
326             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
327                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
328             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
329                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
330
331             skip_bits1(&s->gb); /* marker */
332         }else
333             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
334         s->mb_intra = 1;
335 #ifdef HAVE_XVMC
336         //one 1 we memcpy blocks in xvmcvideo
337         if(s->avctx->xvmc_acceleration > 1){
338             XVMC_pack_pblocks(s,-1);//inter are always full blocks
339             if(s->swap_uv){
340                 exchange_uv(s);
341             }
342         }
343 #endif
344
345         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
346             if(s->flags2 & CODEC_FLAG2_FAST){
347                 for(i=0;i<6;i++) {
348                     mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);
349                 }
350             }else{
351                 for(i=0;i<mb_block_count;i++) {
352                     if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
353                         return -1;
354                 }
355             }
356         } else {
357             for(i=0;i<6;i++) {
358                 if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
359                     return -1;
360             }
361         }
362     } else {
363         if (mb_type & MB_TYPE_ZERO_MV){
364             assert(mb_type & MB_TYPE_CBP);
365
366             /* compute dct type */
367             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
368                 !s->frame_pred_frame_dct) {
369                 s->interlaced_dct = get_bits1(&s->gb);
370             }
371
372             if (IS_QUANT(mb_type))
373                 s->qscale = get_qscale(s);
374
375             s->mv_dir = MV_DIR_FORWARD;
376             if(s->picture_structure == PICT_FRAME)
377                 s->mv_type = MV_TYPE_16X16;
378             else{
379                 s->mv_type = MV_TYPE_FIELD;
380                 mb_type |= MB_TYPE_INTERLACED;
381                 s->field_select[0][0]= s->picture_structure - 1;
382             }
383             s->last_mv[0][0][0] = 0;
384             s->last_mv[0][0][1] = 0;
385             s->last_mv[0][1][0] = 0;
386             s->last_mv[0][1][1] = 0;
387             s->mv[0][0][0] = 0;
388             s->mv[0][0][1] = 0;
389         }else{
390             assert(mb_type & MB_TYPE_L0L1);
391 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
392             /* get additional motion vector type */
393             if (s->frame_pred_frame_dct)
394                 motion_type = MT_FRAME;
395             else{
396                 motion_type = get_bits(&s->gb, 2);
397             }
398
399             /* compute dct type */
400             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
401                 !s->frame_pred_frame_dct && HAS_CBP(mb_type)) {
402                 s->interlaced_dct = get_bits1(&s->gb);
403             }
404
405             if (IS_QUANT(mb_type))
406                 s->qscale = get_qscale(s);
407
408             /* motion vectors */
409             s->mv_dir = 0;
410             for(i=0;i<2;i++) {
411                 if (USES_LIST(mb_type, i)) {
412                     s->mv_dir |= (MV_DIR_FORWARD >> i);
413                     dprintf(s->avctx, "motion_type=%d\n", motion_type);
414                     switch(motion_type) {
415                     case MT_FRAME: /* or MT_16X8 */
416                         if (s->picture_structure == PICT_FRAME) {
417                             /* MT_FRAME */
418                             mb_type |= MB_TYPE_16x16;
419                             s->mv_type = MV_TYPE_16X16;
420                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
421                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
422                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
423                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
424                             /* full_pel: only for mpeg1 */
425                             if (s->full_pel[i]){
426                                 s->mv[i][0][0] <<= 1;
427                                 s->mv[i][0][1] <<= 1;
428                             }
429                         } else {
430                             /* MT_16X8 */
431                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
432                             s->mv_type = MV_TYPE_16X8;
433                             for(j=0;j<2;j++) {
434                                 s->field_select[i][j] = 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][j][k]);
438                                     s->last_mv[i][j][k] = val;
439                                     s->mv[i][j][k] = val;
440                                 }
441                             }
442                         }
443                         break;
444                     case MT_FIELD:
445                         s->mv_type = MV_TYPE_FIELD;
446                         if (s->picture_structure == PICT_FRAME) {
447                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
448                             for(j=0;j<2;j++) {
449                                 s->field_select[i][j] = get_bits1(&s->gb);
450                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
451                                                          s->last_mv[i][j][0]);
452                                 s->last_mv[i][j][0] = val;
453                                 s->mv[i][j][0] = val;
454                                 dprintf(s->avctx, "fmx=%d\n", val);
455                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
456                                                          s->last_mv[i][j][1] >> 1);
457                                 s->last_mv[i][j][1] = val << 1;
458                                 s->mv[i][j][1] = val;
459                                 dprintf(s->avctx, "fmy=%d\n", val);
460                             }
461                         } else {
462                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
463                             s->field_select[i][0] = get_bits1(&s->gb);
464                             for(k=0;k<2;k++) {
465                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
466                                                          s->last_mv[i][0][k]);
467                                 s->last_mv[i][0][k] = val;
468                                 s->last_mv[i][1][k] = val;
469                                 s->mv[i][0][k] = val;
470                             }
471                         }
472                         break;
473                     case MT_DMV:
474                         {
475                             int dmx, dmy, mx, my, m;
476
477                             mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
478                                                     s->last_mv[i][0][0]);
479                             s->last_mv[i][0][0] = mx;
480                             s->last_mv[i][1][0] = mx;
481                             dmx = get_dmv(s);
482                             my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
483                                                     s->last_mv[i][0][1] >> 1);
484                             dmy = get_dmv(s);
485                             s->mv_type = MV_TYPE_DMV;
486
487
488                             s->last_mv[i][0][1] = my<<1;
489                             s->last_mv[i][1][1] = my<<1;
490
491                             s->mv[i][0][0] = mx;
492                             s->mv[i][0][1] = my;
493                             s->mv[i][1][0] = mx;//not used
494                             s->mv[i][1][1] = my;//not used
495
496                             if (s->picture_structure == PICT_FRAME) {
497                                 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
498
499                                 //m = 1 + 2 * s->top_field_first;
500                                 m = s->top_field_first ? 1 : 3;
501
502                                 /* top -> top pred */
503                                 s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
504                                 s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
505                                 m = 4 - m;
506                                 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
507                                 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
508                             } else {
509                                 mb_type |= MB_TYPE_16x16;
510
511                                 s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
512                                 s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
513                                 if(s->picture_structure == PICT_TOP_FIELD)
514                                     s->mv[i][2][1]--;
515                                 else
516                                     s->mv[i][2][1]++;
517                             }
518                         }
519                         break;
520                     default:
521                         av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
522                         return -1;
523                     }
524                 }
525             }
526         }
527
528         s->mb_intra = 0;
529         if (HAS_CBP(mb_type)) {
530             s->dsp.clear_blocks(s->block[0]);
531
532             if(!s->chroma_y_shift){
533                 s->dsp.clear_blocks(s->block[6]);
534             }
535
536             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
537             if (cbp < 0 || ((cbp == 0) && (s->chroma_format < 2)) ){
538                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
539                 return -1;
540             }
541             if(mb_block_count > 6){
542                  cbp<<= mb_block_count-6;
543                  cbp |= get_bits(&s->gb, mb_block_count-6);
544             }
545
546 #ifdef HAVE_XVMC
547             //on 1 we memcpy blocks in xvmcvideo
548             if(s->avctx->xvmc_acceleration > 1){
549                 XVMC_pack_pblocks(s,cbp);
550                 if(s->swap_uv){
551                     exchange_uv(s);
552                 }
553             }
554 #endif
555
556             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
557                 if(s->flags2 & CODEC_FLAG2_FAST){
558                     for(i=0;i<6;i++) {
559                         if(cbp & 32) {
560                             mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);
561                         } else {
562                             s->block_last_index[i] = -1;
563                         }
564                         cbp+=cbp;
565                     }
566                 }else{
567                     cbp<<= 12-mb_block_count;
568
569                     for(i=0;i<mb_block_count;i++) {
570                         if ( cbp & (1<<11) ) {
571                             if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
572                                 return -1;
573                         } else {
574                             s->block_last_index[i] = -1;
575                         }
576                         cbp+=cbp;
577                     }
578                 }
579             } else {
580                 if(s->flags2 & CODEC_FLAG2_FAST){
581                     for(i=0;i<6;i++) {
582                         if (cbp & 32) {
583                             mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);
584                         } else {
585                             s->block_last_index[i] = -1;
586                         }
587                         cbp+=cbp;
588                     }
589                 }else{
590                     for(i=0;i<6;i++) {
591                         if (cbp & 32) {
592                             if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)
593                                 return -1;
594                         } else {
595                             s->block_last_index[i] = -1;
596                         }
597                         cbp+=cbp;
598                     }
599                 }
600             }
601         }else{
602             for(i=0;i<12;i++)
603                 s->block_last_index[i] = -1;
604         }
605     }
606
607     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
608
609     return 0;
610 }
611
612 /* as h263, but only 17 codes */
613 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
614 {
615     int code, sign, val, l, shift;
616
617     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
618     if (code == 0) {
619         return pred;
620     }
621     if (code < 0) {
622         return 0xffff;
623     }
624
625     sign = get_bits1(&s->gb);
626     shift = fcode - 1;
627     val = code;
628     if (shift) {
629         val = (val - 1) << shift;
630         val |= get_bits(&s->gb, shift);
631         val++;
632     }
633     if (sign)
634         val = -val;
635     val += pred;
636
637     /* modulo decoding */
638     l= INT_BIT - 5 - shift;
639     val = (val<<l)>>l;
640     return val;
641 }
642
643 static inline int decode_dc(GetBitContext *gb, int component)
644 {
645     int code, diff;
646
647     if (component == 0) {
648         code = get_vlc2(gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
649     } else {
650         code = get_vlc2(gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
651     }
652     if (code < 0){
653         av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
654         return 0xffff;
655     }
656     if (code == 0) {
657         diff = 0;
658     } else {
659         diff = get_xbits(gb, code);
660     }
661     return diff;
662 }
663
664 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
665                                DCTELEM *block,
666                                int n)
667 {
668     int level, dc, diff, i, j, run;
669     int component;
670     RLTable *rl = &ff_rl_mpeg1;
671     uint8_t * const scantable= s->intra_scantable.permutated;
672     const uint16_t *quant_matrix= s->intra_matrix;
673     const int qscale= s->qscale;
674
675     /* DC coef */
676     component = (n <= 3 ? 0 : n - 4 + 1);
677     diff = decode_dc(&s->gb, component);
678     if (diff >= 0xffff)
679         return -1;
680     dc = s->last_dc[component];
681     dc += diff;
682     s->last_dc[component] = dc;
683     block[0] = dc<<3;
684     dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
685     i = 0;
686     {
687         OPEN_READER(re, &s->gb);
688         /* now quantify & encode AC coefs */
689         for(;;) {
690             UPDATE_CACHE(re, &s->gb);
691             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
692
693             if(level == 127){
694                 break;
695             } else if(level != 0) {
696                 i += run;
697                 j = scantable[i];
698                 level= (level*qscale*quant_matrix[j])>>4;
699                 level= (level-1)|1;
700                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
701                 LAST_SKIP_BITS(re, &s->gb, 1);
702             } else {
703                 /* escape */
704                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
705                 UPDATE_CACHE(re, &s->gb);
706                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
707                 if (level == -128) {
708                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
709                 } else if (level == 0) {
710                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
711                 }
712                 i += run;
713                 j = scantable[i];
714                 if(level<0){
715                     level= -level;
716                     level= (level*qscale*quant_matrix[j])>>4;
717                     level= (level-1)|1;
718                     level= -level;
719                 }else{
720                     level= (level*qscale*quant_matrix[j])>>4;
721                     level= (level-1)|1;
722                 }
723             }
724             if (i > 63){
725                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
726                 return -1;
727             }
728
729             block[j] = level;
730         }
731         CLOSE_READER(re, &s->gb);
732     }
733     s->block_last_index[n] = i;
734    return 0;
735 }
736
737 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
738                                DCTELEM *block,
739                                int n)
740 {
741     int level, i, j, run;
742     RLTable *rl = &ff_rl_mpeg1;
743     uint8_t * const scantable= s->intra_scantable.permutated;
744     const uint16_t *quant_matrix= s->inter_matrix;
745     const int qscale= s->qscale;
746
747     {
748         OPEN_READER(re, &s->gb);
749         i = -1;
750         /* special case for the first coef. no need to add a second vlc table */
751         UPDATE_CACHE(re, &s->gb);
752         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
753             level= (3*qscale*quant_matrix[0])>>5;
754             level= (level-1)|1;
755             if(GET_CACHE(re, &s->gb)&0x40000000)
756                 level= -level;
757             block[0] = level;
758             i++;
759             SKIP_BITS(re, &s->gb, 2);
760             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
761                 goto end;
762         }
763
764         /* now quantify & encode AC coefs */
765         for(;;) {
766             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
767
768             if(level != 0) {
769                 i += run;
770                 j = scantable[i];
771                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
772                 level= (level-1)|1;
773                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
774                 SKIP_BITS(re, &s->gb, 1);
775             } else {
776                 /* escape */
777                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
778                 UPDATE_CACHE(re, &s->gb);
779                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
780                 if (level == -128) {
781                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
782                 } else if (level == 0) {
783                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
784                 }
785                 i += run;
786                 j = scantable[i];
787                 if(level<0){
788                     level= -level;
789                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
790                     level= (level-1)|1;
791                     level= -level;
792                 }else{
793                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
794                     level= (level-1)|1;
795                 }
796             }
797             if (i > 63){
798                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
799                 return -1;
800             }
801
802             block[j] = level;
803             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
804                 break;
805             UPDATE_CACHE(re, &s->gb);
806         }
807 end:
808         LAST_SKIP_BITS(re, &s->gb, 2);
809         CLOSE_READER(re, &s->gb);
810     }
811     s->block_last_index[n] = i;
812     return 0;
813 }
814
815 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
816 {
817     int level, i, j, run;
818     RLTable *rl = &ff_rl_mpeg1;
819     uint8_t * const scantable= s->intra_scantable.permutated;
820     const int qscale= s->qscale;
821
822     {
823         OPEN_READER(re, &s->gb);
824         i = -1;
825         /* special case for the first coef. no need to add a second vlc table */
826         UPDATE_CACHE(re, &s->gb);
827         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
828             level= (3*qscale)>>1;
829             level= (level-1)|1;
830             if(GET_CACHE(re, &s->gb)&0x40000000)
831                 level= -level;
832             block[0] = level;
833             i++;
834             SKIP_BITS(re, &s->gb, 2);
835             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
836                 goto end;
837         }
838
839         /* now quantify & encode AC coefs */
840         for(;;) {
841             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
842
843             if(level != 0) {
844                 i += run;
845                 j = scantable[i];
846                 level= ((level*2+1)*qscale)>>1;
847                 level= (level-1)|1;
848                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
849                 SKIP_BITS(re, &s->gb, 1);
850             } else {
851                 /* escape */
852                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
853                 UPDATE_CACHE(re, &s->gb);
854                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
855                 if (level == -128) {
856                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
857                 } else if (level == 0) {
858                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
859                 }
860                 i += run;
861                 j = scantable[i];
862                 if(level<0){
863                     level= -level;
864                     level= ((level*2+1)*qscale)>>1;
865                     level= (level-1)|1;
866                     level= -level;
867                 }else{
868                     level= ((level*2+1)*qscale)>>1;
869                     level= (level-1)|1;
870                 }
871             }
872
873             block[j] = level;
874             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
875                 break;
876             UPDATE_CACHE(re, &s->gb);
877         }
878 end:
879         LAST_SKIP_BITS(re, &s->gb, 2);
880         CLOSE_READER(re, &s->gb);
881     }
882     s->block_last_index[n] = i;
883     return 0;
884 }
885
886
887 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
888                                DCTELEM *block,
889                                int n)
890 {
891     int level, i, j, run;
892     RLTable *rl = &ff_rl_mpeg1;
893     uint8_t * const scantable= s->intra_scantable.permutated;
894     const uint16_t *quant_matrix;
895     const int qscale= s->qscale;
896     int mismatch;
897
898     mismatch = 1;
899
900     {
901         OPEN_READER(re, &s->gb);
902         i = -1;
903         if (n < 4)
904             quant_matrix = s->inter_matrix;
905         else
906             quant_matrix = s->chroma_inter_matrix;
907
908         /* special case for the first coef. no need to add a second vlc table */
909         UPDATE_CACHE(re, &s->gb);
910         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
911             level= (3*qscale*quant_matrix[0])>>5;
912             if(GET_CACHE(re, &s->gb)&0x40000000)
913                 level= -level;
914             block[0] = level;
915             mismatch ^= level;
916             i++;
917             SKIP_BITS(re, &s->gb, 2);
918             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
919                 goto end;
920         }
921
922         /* now quantify & encode AC coefs */
923         for(;;) {
924             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
925
926             if(level != 0) {
927                 i += run;
928                 j = scantable[i];
929                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
930                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
931                 SKIP_BITS(re, &s->gb, 1);
932             } else {
933                 /* escape */
934                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
935                 UPDATE_CACHE(re, &s->gb);
936                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
937
938                 i += run;
939                 j = scantable[i];
940                 if(level<0){
941                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
942                     level= -level;
943                 }else{
944                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
945                 }
946             }
947             if (i > 63){
948                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
949                 return -1;
950             }
951
952             mismatch ^= level;
953             block[j] = level;
954             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
955                 break;
956             UPDATE_CACHE(re, &s->gb);
957         }
958 end:
959         LAST_SKIP_BITS(re, &s->gb, 2);
960         CLOSE_READER(re, &s->gb);
961     }
962     block[63] ^= (mismatch & 1);
963
964     s->block_last_index[n] = i;
965     return 0;
966 }
967
968 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
969                                DCTELEM *block,
970                                int n)
971 {
972     int level, i, j, run;
973     RLTable *rl = &ff_rl_mpeg1;
974     uint8_t * const scantable= s->intra_scantable.permutated;
975     const int qscale= s->qscale;
976     OPEN_READER(re, &s->gb);
977     i = -1;
978
979     /* special case for the first coef. no need to add a second vlc table */
980     UPDATE_CACHE(re, &s->gb);
981     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
982         level= (3*qscale)>>1;
983         if(GET_CACHE(re, &s->gb)&0x40000000)
984             level= -level;
985         block[0] = level;
986         i++;
987         SKIP_BITS(re, &s->gb, 2);
988         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
989             goto end;
990     }
991
992     /* now quantify & encode AC coefs */
993     for(;;) {
994         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
995
996         if(level != 0) {
997             i += run;
998             j = scantable[i];
999             level= ((level*2+1)*qscale)>>1;
1000             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1001             SKIP_BITS(re, &s->gb, 1);
1002         } else {
1003             /* escape */
1004             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1005             UPDATE_CACHE(re, &s->gb);
1006             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1007
1008             i += run;
1009             j = scantable[i];
1010             if(level<0){
1011                 level= ((-level*2+1)*qscale)>>1;
1012                 level= -level;
1013             }else{
1014                 level= ((level*2+1)*qscale)>>1;
1015             }
1016         }
1017
1018         block[j] = level;
1019         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1020             break;
1021         UPDATE_CACHE(re, &s->gb);
1022     }
1023 end:
1024     LAST_SKIP_BITS(re, &s->gb, 2);
1025     CLOSE_READER(re, &s->gb);
1026     s->block_last_index[n] = i;
1027     return 0;
1028 }
1029
1030
1031 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1032                                DCTELEM *block,
1033                                int n)
1034 {
1035     int level, dc, diff, i, j, run;
1036     int component;
1037     RLTable *rl;
1038     uint8_t * const scantable= s->intra_scantable.permutated;
1039     const uint16_t *quant_matrix;
1040     const int qscale= s->qscale;
1041     int mismatch;
1042
1043     /* DC coef */
1044     if (n < 4){
1045         quant_matrix = s->intra_matrix;
1046         component = 0;
1047     }else{
1048         quant_matrix = s->chroma_intra_matrix;
1049         component = (n&1) + 1;
1050     }
1051     diff = decode_dc(&s->gb, component);
1052     if (diff >= 0xffff)
1053         return -1;
1054     dc = s->last_dc[component];
1055     dc += diff;
1056     s->last_dc[component] = dc;
1057     block[0] = dc << (3 - s->intra_dc_precision);
1058     dprintf(s->avctx, "dc=%d\n", block[0]);
1059     mismatch = block[0] ^ 1;
1060     i = 0;
1061     if (s->intra_vlc_format)
1062         rl = &ff_rl_mpeg2;
1063     else
1064         rl = &ff_rl_mpeg1;
1065
1066     {
1067         OPEN_READER(re, &s->gb);
1068         /* now quantify & encode AC coefs */
1069         for(;;) {
1070             UPDATE_CACHE(re, &s->gb);
1071             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1072
1073             if(level == 127){
1074                 break;
1075             } else if(level != 0) {
1076                 i += run;
1077                 j = scantable[i];
1078                 level= (level*qscale*quant_matrix[j])>>4;
1079                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1080                 LAST_SKIP_BITS(re, &s->gb, 1);
1081             } else {
1082                 /* escape */
1083                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1084                 UPDATE_CACHE(re, &s->gb);
1085                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1086                 i += run;
1087                 j = scantable[i];
1088                 if(level<0){
1089                     level= (-level*qscale*quant_matrix[j])>>4;
1090                     level= -level;
1091                 }else{
1092                     level= (level*qscale*quant_matrix[j])>>4;
1093                 }
1094             }
1095             if (i > 63){
1096                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1097                 return -1;
1098             }
1099
1100             mismatch^= level;
1101             block[j] = level;
1102         }
1103         CLOSE_READER(re, &s->gb);
1104     }
1105     block[63]^= mismatch&1;
1106
1107     s->block_last_index[n] = i;
1108     return 0;
1109 }
1110
1111 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
1112                                DCTELEM *block,
1113                                int n)
1114 {
1115     int level, dc, diff, j, run;
1116     int component;
1117     RLTable *rl;
1118     uint8_t * scantable= s->intra_scantable.permutated;
1119     const uint16_t *quant_matrix;
1120     const int qscale= s->qscale;
1121
1122     /* DC coef */
1123     if (n < 4){
1124         quant_matrix = s->intra_matrix;
1125         component = 0;
1126     }else{
1127         quant_matrix = s->chroma_intra_matrix;
1128         component = (n&1) + 1;
1129     }
1130     diff = decode_dc(&s->gb, component);
1131     if (diff >= 0xffff)
1132         return -1;
1133     dc = s->last_dc[component];
1134     dc += diff;
1135     s->last_dc[component] = dc;
1136     block[0] = dc << (3 - s->intra_dc_precision);
1137     if (s->intra_vlc_format)
1138         rl = &ff_rl_mpeg2;
1139     else
1140         rl = &ff_rl_mpeg1;
1141
1142     {
1143         OPEN_READER(re, &s->gb);
1144         /* now quantify & encode AC coefs */
1145         for(;;) {
1146             UPDATE_CACHE(re, &s->gb);
1147             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1148
1149             if(level == 127){
1150                 break;
1151             } else if(level != 0) {
1152                 scantable += run;
1153                 j = *scantable;
1154                 level= (level*qscale*quant_matrix[j])>>4;
1155                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1156                 LAST_SKIP_BITS(re, &s->gb, 1);
1157             } else {
1158                 /* escape */
1159                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1160                 UPDATE_CACHE(re, &s->gb);
1161                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1162                 scantable += run;
1163                 j = *scantable;
1164                 if(level<0){
1165                     level= (-level*qscale*quant_matrix[j])>>4;
1166                     level= -level;
1167                 }else{
1168                     level= (level*qscale*quant_matrix[j])>>4;
1169                 }
1170             }
1171
1172             block[j] = level;
1173         }
1174         CLOSE_READER(re, &s->gb);
1175     }
1176
1177     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
1178     return 0;
1179 }
1180
1181 typedef struct Mpeg1Context {
1182     MpegEncContext mpeg_enc_ctx;
1183     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1184     int repeat_field; /* true if we must repeat the field */
1185     AVPanScan pan_scan; /** some temporary storage for the panscan */
1186     int slice_count;
1187     int swap_uv;//indicate VCR2
1188     int save_aspect_info;
1189     int save_width, save_height;
1190     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1191
1192 } Mpeg1Context;
1193
1194 static int mpeg_decode_init(AVCodecContext *avctx)
1195 {
1196     Mpeg1Context *s = avctx->priv_data;
1197     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1198     int i;
1199
1200     //we need some parmutation to store
1201     //matrixes, until MPV_common_init()
1202     //set the real permutatuon
1203     for(i=0;i<64;i++)
1204        s2->dsp.idct_permutation[i]=i;
1205
1206     MPV_decode_defaults(s2);
1207
1208     s->mpeg_enc_ctx.avctx= avctx;
1209     s->mpeg_enc_ctx.flags= avctx->flags;
1210     s->mpeg_enc_ctx.flags2= avctx->flags2;
1211     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1212     init_vlcs();
1213
1214     s->mpeg_enc_ctx_allocated = 0;
1215     s->mpeg_enc_ctx.picture_number = 0;
1216     s->repeat_field = 0;
1217     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1218     return 0;
1219 }
1220
1221 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1222                                      const uint8_t *new_perm){
1223     uint16_t temp_matrix[64];
1224     int i;
1225
1226     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1227
1228     for(i=0;i<64;i++){
1229         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1230     }
1231 }
1232
1233 //Call this function when we know all parameters
1234 //it may be called in different places for mpeg1 and mpeg2
1235 static int mpeg_decode_postinit(AVCodecContext *avctx){
1236     Mpeg1Context *s1 = avctx->priv_data;
1237     MpegEncContext *s = &s1->mpeg_enc_ctx;
1238     uint8_t old_permutation[64];
1239
1240     if (
1241         (s1->mpeg_enc_ctx_allocated == 0)||
1242         avctx->coded_width  != s->width ||
1243         avctx->coded_height != s->height||
1244         s1->save_width != s->width ||
1245         s1->save_height != s->height ||
1246         s1->save_aspect_info != s->aspect_ratio_info||
1247         0)
1248     {
1249
1250         if (s1->mpeg_enc_ctx_allocated) {
1251             ParseContext pc= s->parse_context;
1252             s->parse_context.buffer=0;
1253             MPV_common_end(s);
1254             s->parse_context= pc;
1255         }
1256
1257         if( (s->width == 0 )||(s->height == 0))
1258             return -2;
1259
1260         avcodec_set_dimensions(avctx, s->width, s->height);
1261         avctx->bit_rate = s->bit_rate;
1262         s1->save_aspect_info = s->aspect_ratio_info;
1263         s1->save_width = s->width;
1264         s1->save_height = s->height;
1265
1266      //low_delay may be forced, in this case we will have B frames
1267      //that behave like P frames
1268         avctx->has_b_frames = !(s->low_delay);
1269
1270         if(avctx->sub_id==1){//s->codec_id==avctx->codec_id==CODEC_ID
1271             //mpeg1 fps
1272             avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
1273             avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
1274             //mpeg1 aspect
1275             avctx->sample_aspect_ratio= av_d2q(
1276                     1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1277
1278         }else{//mpeg2
1279         //mpeg2 fps
1280             av_reduce(
1281                 &s->avctx->time_base.den,
1282                 &s->avctx->time_base.num,
1283                 ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1284                 ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1285                 1<<30);
1286         //mpeg2 aspect
1287             if(s->aspect_ratio_info > 1){
1288                 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) ){
1289                     s->avctx->sample_aspect_ratio=
1290                         av_div_q(
1291                          ff_mpeg2_aspect[s->aspect_ratio_info],
1292                          (AVRational){s->width, s->height}
1293                          );
1294                 }else{
1295                     s->avctx->sample_aspect_ratio=
1296                         av_div_q(
1297                          ff_mpeg2_aspect[s->aspect_ratio_info],
1298                          (AVRational){s1->pan_scan.width, s1->pan_scan.height}
1299                         );
1300                 }
1301             }else{
1302                 s->avctx->sample_aspect_ratio=
1303                     ff_mpeg2_aspect[s->aspect_ratio_info];
1304             }
1305         }//mpeg2
1306
1307         if(avctx->xvmc_acceleration){
1308             avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
1309         }else{
1310             if(s->chroma_format <  2){
1311                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
1312             }else
1313             if(s->chroma_format == 2){
1314                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_422);
1315             }else
1316             if(s->chroma_format >  2){
1317                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_444);
1318             }
1319         }
1320         //until then pix_fmt may be changed right after codec init
1321         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
1322             if( avctx->idct_algo == FF_IDCT_AUTO )
1323                 avctx->idct_algo = FF_IDCT_SIMPLE;
1324
1325         //quantization matrixes may need reordering
1326         //if dct permutation is changed
1327         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
1328
1329         if (MPV_common_init(s) < 0)
1330             return -2;
1331
1332         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
1333         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
1334         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
1335         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
1336
1337         s1->mpeg_enc_ctx_allocated = 1;
1338     }
1339     return 0;
1340 }
1341
1342 static int mpeg1_decode_picture(AVCodecContext *avctx,
1343                                 const uint8_t *buf, int buf_size)
1344 {
1345     Mpeg1Context *s1 = avctx->priv_data;
1346     MpegEncContext *s = &s1->mpeg_enc_ctx;
1347     int ref, f_code, vbv_delay;
1348
1349     if(mpeg_decode_postinit(s->avctx) < 0)
1350        return -2;
1351
1352     init_get_bits(&s->gb, buf, buf_size*8);
1353
1354     ref = get_bits(&s->gb, 10); /* temporal ref */
1355     s->pict_type = get_bits(&s->gb, 3);
1356     if(s->pict_type == 0 || s->pict_type > 3)
1357         return -1;
1358
1359     vbv_delay= get_bits(&s->gb, 16);
1360     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
1361         s->full_pel[0] = get_bits1(&s->gb);
1362         f_code = get_bits(&s->gb, 3);
1363         if (f_code == 0 && avctx->error_resilience >= FF_ER_COMPLIANT)
1364             return -1;
1365         s->mpeg_f_code[0][0] = f_code;
1366         s->mpeg_f_code[0][1] = f_code;
1367     }
1368     if (s->pict_type == B_TYPE) {
1369         s->full_pel[1] = get_bits1(&s->gb);
1370         f_code = get_bits(&s->gb, 3);
1371         if (f_code == 0 && avctx->error_resilience >= FF_ER_COMPLIANT)
1372             return -1;
1373         s->mpeg_f_code[1][0] = f_code;
1374         s->mpeg_f_code[1][1] = f_code;
1375     }
1376     s->current_picture.pict_type= s->pict_type;
1377     s->current_picture.key_frame= s->pict_type == I_TYPE;
1378
1379     if(avctx->debug & FF_DEBUG_PICT_INFO)
1380         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1381
1382     s->y_dc_scale = 8;
1383     s->c_dc_scale = 8;
1384     s->first_slice = 1;
1385     return 0;
1386 }
1387
1388 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1389 {
1390     MpegEncContext *s= &s1->mpeg_enc_ctx;
1391     int horiz_size_ext, vert_size_ext;
1392     int bit_rate_ext;
1393
1394     skip_bits(&s->gb, 1); /* profil and level esc*/
1395     s->avctx->profile= get_bits(&s->gb, 3);
1396     s->avctx->level= get_bits(&s->gb, 4);
1397     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1398     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1399     horiz_size_ext = get_bits(&s->gb, 2);
1400     vert_size_ext = get_bits(&s->gb, 2);
1401     s->width |= (horiz_size_ext << 12);
1402     s->height |= (vert_size_ext << 12);
1403     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1404     s->bit_rate += (bit_rate_ext << 18) * 400;
1405     skip_bits1(&s->gb); /* marker */
1406     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
1407
1408     s->low_delay = get_bits1(&s->gb);
1409     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
1410
1411     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
1412     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
1413
1414     dprintf(s->avctx, "sequence extension\n");
1415     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
1416     s->avctx->sub_id = 2; /* indicates mpeg2 found */
1417
1418     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1419         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1420                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1421
1422 }
1423
1424 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1425 {
1426     MpegEncContext *s= &s1->mpeg_enc_ctx;
1427     int color_description, w, h;
1428
1429     skip_bits(&s->gb, 3); /* video format */
1430     color_description= get_bits1(&s->gb);
1431     if(color_description){
1432         skip_bits(&s->gb, 8); /* color primaries */
1433         skip_bits(&s->gb, 8); /* transfer_characteristics */
1434         skip_bits(&s->gb, 8); /* matrix_coefficients */
1435     }
1436     w= get_bits(&s->gb, 14);
1437     skip_bits(&s->gb, 1); //marker
1438     h= get_bits(&s->gb, 14);
1439     skip_bits(&s->gb, 1); //marker
1440
1441     s1->pan_scan.width= 16*w;
1442     s1->pan_scan.height=16*h;
1443
1444     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1445         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1446 }
1447
1448 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1449 {
1450     MpegEncContext *s= &s1->mpeg_enc_ctx;
1451     int i,nofco;
1452
1453     nofco = 1;
1454     if(s->progressive_sequence){
1455         if(s->repeat_first_field){
1456             nofco++;
1457             if(s->top_field_first)
1458                 nofco++;
1459         }
1460     }else{
1461         if(s->picture_structure == PICT_FRAME){
1462             nofco++;
1463             if(s->repeat_first_field)
1464                 nofco++;
1465         }
1466     }
1467     for(i=0; i<nofco; i++){
1468         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
1469         skip_bits(&s->gb, 1); //marker
1470         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
1471         skip_bits(&s->gb, 1); //marker
1472     }
1473
1474     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1475         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1476             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1477             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1478             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
1479         );
1480 }
1481
1482 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1483 {
1484     int i, v, j;
1485
1486     dprintf(s->avctx, "matrix extension\n");
1487
1488     if (get_bits1(&s->gb)) {
1489         for(i=0;i<64;i++) {
1490             v = get_bits(&s->gb, 8);
1491             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1492             s->intra_matrix[j] = v;
1493             s->chroma_intra_matrix[j] = v;
1494         }
1495     }
1496     if (get_bits1(&s->gb)) {
1497         for(i=0;i<64;i++) {
1498             v = get_bits(&s->gb, 8);
1499             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1500             s->inter_matrix[j] = v;
1501             s->chroma_inter_matrix[j] = v;
1502         }
1503     }
1504     if (get_bits1(&s->gb)) {
1505         for(i=0;i<64;i++) {
1506             v = get_bits(&s->gb, 8);
1507             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1508             s->chroma_intra_matrix[j] = v;
1509         }
1510     }
1511     if (get_bits1(&s->gb)) {
1512         for(i=0;i<64;i++) {
1513             v = get_bits(&s->gb, 8);
1514             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1515             s->chroma_inter_matrix[j] = v;
1516         }
1517     }
1518 }
1519
1520 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1521 {
1522     s->full_pel[0] = s->full_pel[1] = 0;
1523     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1524     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1525     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1526     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1527     s->intra_dc_precision = get_bits(&s->gb, 2);
1528     s->picture_structure = get_bits(&s->gb, 2);
1529     s->top_field_first = get_bits1(&s->gb);
1530     s->frame_pred_frame_dct = get_bits1(&s->gb);
1531     s->concealment_motion_vectors = get_bits1(&s->gb);
1532     s->q_scale_type = get_bits1(&s->gb);
1533     s->intra_vlc_format = get_bits1(&s->gb);
1534     s->alternate_scan = get_bits1(&s->gb);
1535     s->repeat_first_field = get_bits1(&s->gb);
1536     s->chroma_420_type = get_bits1(&s->gb);
1537     s->progressive_frame = get_bits1(&s->gb);
1538
1539     if(s->picture_structure == PICT_FRAME){
1540         s->first_field=0;
1541         s->v_edge_pos= 16*s->mb_height;
1542     }else{
1543         s->first_field ^= 1;
1544         s->v_edge_pos=  8*s->mb_height;
1545         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1546     }
1547
1548     if(s->alternate_scan){
1549         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1550         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1551     }else{
1552         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1553         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1554     }
1555
1556     /* composite display not parsed */
1557     dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1558     dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
1559     dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
1560     dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1561     dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1562     dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1563     dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1564     dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1565     dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1566 }
1567
1568 static void mpeg_decode_extension(AVCodecContext *avctx,
1569                                   const uint8_t *buf, int buf_size)
1570 {
1571     Mpeg1Context *s1 = avctx->priv_data;
1572     MpegEncContext *s = &s1->mpeg_enc_ctx;
1573     int ext_type;
1574
1575     init_get_bits(&s->gb, buf, buf_size*8);
1576
1577     ext_type = get_bits(&s->gb, 4);
1578     switch(ext_type) {
1579     case 0x1:
1580         mpeg_decode_sequence_extension(s1);
1581         break;
1582     case 0x2:
1583         mpeg_decode_sequence_display_extension(s1);
1584         break;
1585     case 0x3:
1586         mpeg_decode_quant_matrix_extension(s);
1587         break;
1588     case 0x7:
1589         mpeg_decode_picture_display_extension(s1);
1590         break;
1591     case 0x8:
1592         mpeg_decode_picture_coding_extension(s);
1593         break;
1594     }
1595 }
1596
1597 static void exchange_uv(MpegEncContext *s){
1598     short * tmp = s->pblocks[4];
1599     s->pblocks[4] = s->pblocks[5];
1600     s->pblocks[5] = tmp;
1601 }
1602
1603 static int mpeg_field_start(MpegEncContext *s){
1604     AVCodecContext *avctx= s->avctx;
1605     Mpeg1Context *s1 = (Mpeg1Context*)s;
1606
1607     /* start frame decoding */
1608     if(s->first_field || s->picture_structure==PICT_FRAME){
1609         if(MPV_frame_start(s, avctx) < 0)
1610             return -1;
1611
1612         ff_er_frame_start(s);
1613
1614         /* first check if we must repeat the frame */
1615         s->current_picture_ptr->repeat_pict = 0;
1616         if (s->repeat_first_field) {
1617             if (s->progressive_sequence) {
1618                 if (s->top_field_first)
1619                     s->current_picture_ptr->repeat_pict = 4;
1620                 else
1621                     s->current_picture_ptr->repeat_pict = 2;
1622             } else if (s->progressive_frame) {
1623                 s->current_picture_ptr->repeat_pict = 1;
1624             }
1625         }
1626
1627         *s->current_picture_ptr->pan_scan= s1->pan_scan;
1628     }else{ //second field
1629             int i;
1630
1631             if(!s->current_picture_ptr){
1632                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1633                 return -1;
1634             }
1635
1636             for(i=0; i<4; i++){
1637                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1638                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1639                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1640                 }
1641             }
1642     }
1643 #ifdef HAVE_XVMC
1644 // MPV_frame_start will call this function too,
1645 // but we need to call it on every field
1646     if(s->avctx->xvmc_acceleration)
1647          XVMC_field_start(s,avctx);
1648 #endif
1649
1650     return 0;
1651 }
1652
1653 #define DECODE_SLICE_ERROR -1
1654 #define DECODE_SLICE_OK 0
1655
1656 /**
1657  * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
1658  * @return DECODE_SLICE_ERROR if the slice is damaged<br>
1659  *         DECODE_SLICE_OK if this slice is ok<br>
1660  */
1661 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
1662                              const uint8_t **buf, int buf_size)
1663 {
1664     MpegEncContext *s = &s1->mpeg_enc_ctx;
1665     AVCodecContext *avctx= s->avctx;
1666     int ret;
1667     const int field_pic= s->picture_structure != PICT_FRAME;
1668     const int lowres= s->avctx->lowres;
1669
1670     s->resync_mb_x=
1671     s->resync_mb_y= -1;
1672
1673     if (mb_y<<field_pic >= s->mb_height){
1674         av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
1675         return -1;
1676     }
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     for(;;) {
1698         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1699         if (code < 0){
1700             av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1701             return -1;
1702         }
1703         if (code >= 33) {
1704             if (code == 33) {
1705                 s->mb_x += 33;
1706             }
1707             /* otherwise, stuffing, nothing to do */
1708         } else {
1709             s->mb_x += code;
1710             break;
1711         }
1712     }
1713     if(s->mb_x >= (unsigned)s->mb_width){
1714         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1715         return -1;
1716     }
1717
1718     s->resync_mb_x= s->mb_x;
1719     s->resync_mb_y= s->mb_y= mb_y;
1720     s->mb_skip_run= 0;
1721     ff_init_block_index(s);
1722
1723     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
1724         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1725              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",
1726                  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],
1727                  s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")),
1728                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1729                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1730                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1731         }
1732     }
1733
1734     for(;;) {
1735 #ifdef HAVE_XVMC
1736         //one 1 we memcpy blocks in xvmcvideo
1737         if(s->avctx->xvmc_acceleration > 1)
1738             XVMC_init_block(s);//set s->block
1739 #endif
1740
1741         ret = mpeg_decode_mb(s, s->block);
1742
1743         dprintf(s->avctx, "ret=%d\n", ret);
1744         if (ret < 0)
1745             return -1;
1746
1747         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
1748             const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
1749             int xy = s->mb_x*2 + s->mb_y*2*wrap;
1750             int motion_x, motion_y, dir, i;
1751             if(field_pic && !s->first_field)
1752                 xy += wrap/2;
1753
1754             for(i=0; i<2; i++){
1755                 for(dir=0; dir<2; dir++){
1756                     if (s->mb_intra || (dir==1 && s->pict_type != B_TYPE)) {
1757                         motion_x = motion_y = 0;
1758                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
1759                         motion_x = s->mv[dir][0][0];
1760                         motion_y = s->mv[dir][0][1];
1761                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1762                         motion_x = s->mv[dir][i][0];
1763                         motion_y = s->mv[dir][i][1];
1764                     }
1765
1766                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1767                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1768                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1769                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1770                     s->current_picture.ref_index [dir][xy    ]=
1771                     s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
1772                     assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
1773                 }
1774                 xy += wrap;
1775             }
1776         }
1777
1778         s->dest[0] += 16 >> lowres;
1779         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1780         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1781
1782         MPV_decode_mb(s, s->block);
1783
1784         if (++s->mb_x >= s->mb_width) {
1785             const int mb_size= 16>>s->avctx->lowres;
1786
1787             ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
1788
1789             s->mb_x = 0;
1790             s->mb_y++;
1791
1792             if(s->mb_y<<field_pic >= s->mb_height){
1793                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1794                 int is_d10= s->chroma_format==2 && s->pict_type==I_TYPE && avctx->profile==0 && avctx->level==5
1795                             && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1796                             && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1797
1798                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1799                    || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
1800                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1801                     return -1;
1802                 }else
1803                     goto eos;
1804             }
1805
1806             ff_init_block_index(s);
1807         }
1808
1809         /* skip mb handling */
1810         if (s->mb_skip_run == -1) {
1811             /* read again increment */
1812             s->mb_skip_run = 0;
1813             for(;;) {
1814                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1815                 if (code < 0){
1816                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1817                     return -1;
1818                 }
1819                 if (code >= 33) {
1820                     if (code == 33) {
1821                         s->mb_skip_run += 33;
1822                     }else if(code == 35){
1823                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1824                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1825                             return -1;
1826                         }
1827                         goto eos; /* end of slice */
1828                     }
1829                     /* otherwise, stuffing, nothing to do */
1830                 } else {
1831                     s->mb_skip_run += code;
1832                     break;
1833                 }
1834             }
1835         }
1836     }
1837 eos: // end of slice
1838     *buf += get_bits_count(&s->gb)/8 - 1;
1839 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1840     return 0;
1841 }
1842
1843 static int slice_decode_thread(AVCodecContext *c, void *arg){
1844     MpegEncContext *s= arg;
1845     const uint8_t *buf= s->gb.buffer;
1846     int mb_y= s->start_mb_y;
1847
1848     s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
1849
1850     for(;;){
1851         uint32_t start_code;
1852         int ret;
1853
1854         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
1855         emms_c();
1856 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1857 //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);
1858         if(ret < 0){
1859             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
1860                 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);
1861         }else{
1862             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);
1863         }
1864
1865         if(s->mb_y == s->end_mb_y)
1866             return 0;
1867
1868         start_code= -1;
1869         buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
1870         mb_y= start_code - SLICE_MIN_START_CODE;
1871         if(mb_y < 0 || mb_y >= s->end_mb_y)
1872             return -1;
1873     }
1874
1875     return 0; //not reached
1876 }
1877
1878 /**
1879  * handles slice ends.
1880  * @return 1 if it seems to be the last slice of
1881  */
1882 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1883 {
1884     Mpeg1Context *s1 = avctx->priv_data;
1885     MpegEncContext *s = &s1->mpeg_enc_ctx;
1886
1887     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1888         return 0;
1889
1890 #ifdef HAVE_XVMC
1891     if(s->avctx->xvmc_acceleration)
1892         XVMC_field_end(s);
1893 #endif
1894     /* end of slice reached */
1895     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1896         /* end of image */
1897
1898         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1899
1900         ff_er_frame_end(s);
1901
1902         MPV_frame_end(s);
1903
1904         if (s->pict_type == B_TYPE || s->low_delay) {
1905             *pict= *(AVFrame*)s->current_picture_ptr;
1906             ff_print_debug_info(s, pict);
1907         } else {
1908             s->picture_number++;
1909             /* latency of 1 frame for I and P frames */
1910             /* XXX: use another variable than picture_number */
1911             if (s->last_picture_ptr != NULL) {
1912                 *pict= *(AVFrame*)s->last_picture_ptr;
1913                  ff_print_debug_info(s, pict);
1914             }
1915         }
1916
1917         return 1;
1918     } else {
1919         return 0;
1920     }
1921 }
1922
1923 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1924                                  const uint8_t *buf, int buf_size)
1925 {
1926     Mpeg1Context *s1 = avctx->priv_data;
1927     MpegEncContext *s = &s1->mpeg_enc_ctx;
1928     int width,height;
1929     int i, v, j;
1930
1931     init_get_bits(&s->gb, buf, buf_size*8);
1932
1933     width = get_bits(&s->gb, 12);
1934     height = get_bits(&s->gb, 12);
1935     if (width <= 0 || height <= 0 ||
1936         (width % 2) != 0 || (height % 2) != 0)
1937         return -1;
1938     s->aspect_ratio_info= get_bits(&s->gb, 4);
1939     if (s->aspect_ratio_info == 0)
1940         return -1;
1941     s->frame_rate_index = get_bits(&s->gb, 4);
1942     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1943         return -1;
1944     s->bit_rate = get_bits(&s->gb, 18) * 400;
1945     if (get_bits1(&s->gb) == 0) /* marker */
1946         return -1;
1947     s->width = width;
1948     s->height = height;
1949
1950     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
1951     skip_bits(&s->gb, 1);
1952
1953     /* get matrix */
1954     if (get_bits1(&s->gb)) {
1955         for(i=0;i<64;i++) {
1956             v = get_bits(&s->gb, 8);
1957             if(v==0){
1958                 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
1959                 return -1;
1960             }
1961             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1962             s->intra_matrix[j] = v;
1963             s->chroma_intra_matrix[j] = v;
1964         }
1965 #ifdef DEBUG
1966         dprintf(s->avctx, "intra matrix present\n");
1967         for(i=0;i<64;i++)
1968             dprintf(s->avctx, " %d", s->intra_matrix[s->dsp.idct_permutation[i]]);
1969         dprintf(s->avctx, "\n");
1970 #endif
1971     } else {
1972         for(i=0;i<64;i++) {
1973             j = s->dsp.idct_permutation[i];
1974             v = ff_mpeg1_default_intra_matrix[i];
1975             s->intra_matrix[j] = v;
1976             s->chroma_intra_matrix[j] = v;
1977         }
1978     }
1979     if (get_bits1(&s->gb)) {
1980         for(i=0;i<64;i++) {
1981             v = get_bits(&s->gb, 8);
1982             if(v==0){
1983                 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
1984                 return -1;
1985             }
1986             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1987             s->inter_matrix[j] = v;
1988             s->chroma_inter_matrix[j] = v;
1989         }
1990 #ifdef DEBUG
1991         dprintf(s->avctx, "non intra matrix present\n");
1992         for(i=0;i<64;i++)
1993             dprintf(s->avctx, " %d", s->inter_matrix[s->dsp.idct_permutation[i]]);
1994         dprintf(s->avctx, "\n");
1995 #endif
1996     } else {
1997         for(i=0;i<64;i++) {
1998             int j= s->dsp.idct_permutation[i];
1999             v = ff_mpeg1_default_non_intra_matrix[i];
2000             s->inter_matrix[j] = v;
2001             s->chroma_inter_matrix[j] = v;
2002         }
2003     }
2004
2005     if(show_bits(&s->gb, 23) != 0){
2006         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2007         return -1;
2008     }
2009
2010     /* we set mpeg2 parameters so that it emulates mpeg1 */
2011     s->progressive_sequence = 1;
2012     s->progressive_frame = 1;
2013     s->picture_structure = PICT_FRAME;
2014     s->frame_pred_frame_dct = 1;
2015     s->chroma_format = 1;
2016     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2017     avctx->sub_id = 1; /* indicates mpeg1 */
2018     s->out_format = FMT_MPEG1;
2019     s->swap_uv = 0;//AFAIK VCR2 don't have SEQ_HEADER
2020     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2021
2022     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2023         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2024                s->avctx->rc_buffer_size, s->bit_rate);
2025
2026     return 0;
2027 }
2028
2029 static int vcr2_init_sequence(AVCodecContext *avctx)
2030 {
2031     Mpeg1Context *s1 = avctx->priv_data;
2032     MpegEncContext *s = &s1->mpeg_enc_ctx;
2033     int i, v;
2034
2035     /* start new mpeg1 context decoding */
2036     s->out_format = FMT_MPEG1;
2037     if (s1->mpeg_enc_ctx_allocated) {
2038         MPV_common_end(s);
2039     }
2040     s->width  = avctx->coded_width;
2041     s->height = avctx->coded_height;
2042     avctx->has_b_frames= 0; //true?
2043     s->low_delay= 1;
2044
2045     if(avctx->xvmc_acceleration){
2046         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
2047     }else{
2048         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
2049     }
2050
2051     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
2052         if( avctx->idct_algo == FF_IDCT_AUTO )
2053             avctx->idct_algo = FF_IDCT_SIMPLE;
2054
2055     if (MPV_common_init(s) < 0)
2056         return -1;
2057     exchange_uv(s);//common init reset pblocks, so we swap them here
2058     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
2059     s1->mpeg_enc_ctx_allocated = 1;
2060
2061     for(i=0;i<64;i++) {
2062         int j= s->dsp.idct_permutation[i];
2063         v = ff_mpeg1_default_intra_matrix[i];
2064         s->intra_matrix[j] = v;
2065         s->chroma_intra_matrix[j] = v;
2066
2067         v = ff_mpeg1_default_non_intra_matrix[i];
2068         s->inter_matrix[j] = v;
2069         s->chroma_inter_matrix[j] = v;
2070     }
2071
2072     s->progressive_sequence = 1;
2073     s->progressive_frame = 1;
2074     s->picture_structure = PICT_FRAME;
2075     s->frame_pred_frame_dct = 1;
2076     s->chroma_format = 1;
2077     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2078     avctx->sub_id = 2; /* indicates mpeg2 */
2079     return 0;
2080 }
2081
2082
2083 static void mpeg_decode_user_data(AVCodecContext *avctx,
2084                                   const uint8_t *buf, int buf_size)
2085 {
2086     const uint8_t *p;
2087     int len, flags;
2088     p = buf;
2089     len = buf_size;
2090
2091     /* we parse the DTG active format information */
2092     if (len >= 5 &&
2093         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2094         flags = p[4];
2095         p += 5;
2096         len -= 5;
2097         if (flags & 0x80) {
2098             /* skip event id */
2099             if (len < 2)
2100                 return;
2101             p += 2;
2102             len -= 2;
2103         }
2104         if (flags & 0x40) {
2105             if (len < 1)
2106                 return;
2107             avctx->dtg_active_format = p[0] & 0x0f;
2108         }
2109     }
2110 }
2111
2112 static void mpeg_decode_gop(AVCodecContext *avctx,
2113                             const uint8_t *buf, int buf_size){
2114     Mpeg1Context *s1 = avctx->priv_data;
2115     MpegEncContext *s = &s1->mpeg_enc_ctx;
2116
2117     int drop_frame_flag;
2118     int time_code_hours, time_code_minutes;
2119     int time_code_seconds, time_code_pictures;
2120     int broken_link;
2121
2122     init_get_bits(&s->gb, buf, buf_size*8);
2123
2124     drop_frame_flag = get_bits1(&s->gb);
2125
2126     time_code_hours=get_bits(&s->gb,5);
2127     time_code_minutes = get_bits(&s->gb,6);
2128     skip_bits1(&s->gb);//marker bit
2129     time_code_seconds = get_bits(&s->gb,6);
2130     time_code_pictures = get_bits(&s->gb,6);
2131
2132     /*broken_link indicate that after editing the
2133       reference frames of the first B-Frames after GOP I-Frame
2134       are missing (open gop)*/
2135     broken_link = get_bits1(&s->gb);
2136
2137     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2138         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) broken_link=%d\n",
2139             time_code_hours, time_code_minutes, time_code_seconds,
2140             time_code_pictures, broken_link);
2141 }
2142 /**
2143  * finds the end of the current frame in the bitstream.
2144  * @return the position of the first byte of the next frame, or -1
2145  */
2146 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
2147 {
2148     int i;
2149     uint32_t state= pc->state;
2150
2151     i=0;
2152     if(!pc->frame_start_found){
2153         for(i=0; i<buf_size; i++){
2154             i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2155             if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2156                 i++;
2157                 pc->frame_start_found=1;
2158                 break;
2159             }
2160         }
2161     }
2162
2163     if(pc->frame_start_found){
2164         /* EOF considered as end of frame */
2165         if (buf_size == 0)
2166             return 0;
2167         for(; i<buf_size; i++){
2168             i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2169             if((state&0xFFFFFF00) == 0x100){
2170                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2171                     pc->frame_start_found=0;
2172                     pc->state=-1;
2173                     return i-3;
2174                 }
2175             }
2176         }
2177     }
2178     pc->state= state;
2179     return END_NOT_FOUND;
2180 }
2181
2182 /* handle buffering and image synchronisation */
2183 static int mpeg_decode_frame(AVCodecContext *avctx,
2184                              void *data, int *data_size,
2185                              uint8_t *buf, int buf_size)
2186 {
2187     Mpeg1Context *s = avctx->priv_data;
2188     const uint8_t *buf_end;
2189     const uint8_t *buf_ptr;
2190     uint32_t start_code;
2191     int ret, input_size;
2192     AVFrame *picture = data;
2193     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2194     dprintf(avctx, "fill_buffer\n");
2195
2196     if (buf_size == 0) {
2197         /* special case for last picture */
2198         if (s2->low_delay==0 && s2->next_picture_ptr) {
2199             *picture= *(AVFrame*)s2->next_picture_ptr;
2200             s2->next_picture_ptr= NULL;
2201
2202             *data_size = sizeof(AVFrame);
2203         }
2204         return 0;
2205     }
2206
2207     if(s2->flags&CODEC_FLAG_TRUNCATED){
2208         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size);
2209
2210         if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
2211             return buf_size;
2212     }
2213
2214     buf_ptr = buf;
2215     buf_end = buf + buf_size;
2216
2217 #if 0
2218     if (s->repeat_field % 2 == 1) {
2219         s->repeat_field++;
2220         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2221         //        s2->picture_number, s->repeat_field);
2222         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2223             *data_size = sizeof(AVPicture);
2224             goto the_end;
2225         }
2226     }
2227 #endif
2228
2229     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == ff_get_fourcc("VCR2"))
2230         vcr2_init_sequence(avctx);
2231
2232     s->slice_count= 0;
2233
2234     for(;;) {
2235         /* find start next code */
2236         start_code = -1;
2237         buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
2238         if (start_code > 0x1ff){
2239             if(s2->pict_type != B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
2240                 if(avctx->thread_count > 1){
2241                     int i;
2242
2243                     avctx->execute(avctx, slice_decode_thread,  (void**)&(s2->thread_context[0]), NULL, s->slice_count);
2244                     for(i=0; i<s->slice_count; i++)
2245                         s2->error_count += s2->thread_context[i]->error_count;
2246                 }
2247                 if (slice_end(avctx, picture)) {
2248                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2249                         *data_size = sizeof(AVPicture);
2250                 }
2251             }
2252             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2253         }
2254
2255         input_size = buf_end - buf_ptr;
2256
2257         if(avctx->debug & FF_DEBUG_STARTCODE){
2258             av_log(avctx, AV_LOG_DEBUG, "%3X at %zd left %d\n", start_code, buf_ptr-buf, input_size);
2259         }
2260
2261         /* prepare data for next start code */
2262         switch(start_code) {
2263         case SEQ_START_CODE:
2264             mpeg1_decode_sequence(avctx, buf_ptr,
2265                                     input_size);
2266             break;
2267
2268         case PICTURE_START_CODE:
2269             /* we have a complete image : we try to decompress it */
2270             mpeg1_decode_picture(avctx,
2271                                     buf_ptr, input_size);
2272             break;
2273         case EXT_START_CODE:
2274             mpeg_decode_extension(avctx,
2275                                     buf_ptr, input_size);
2276             break;
2277         case USER_START_CODE:
2278             mpeg_decode_user_data(avctx,
2279                                     buf_ptr, input_size);
2280             break;
2281         case GOP_START_CODE:
2282             s2->first_field=0;
2283             mpeg_decode_gop(avctx,
2284                                     buf_ptr, input_size);
2285             break;
2286         default:
2287             if (start_code >= SLICE_MIN_START_CODE &&
2288                 start_code <= SLICE_MAX_START_CODE) {
2289                 int mb_y= start_code - SLICE_MIN_START_CODE;
2290
2291                 if(s2->last_picture_ptr==NULL){
2292                 /* Skip B-frames if we do not have reference frames. */
2293                     if(s2->pict_type==B_TYPE) break;
2294                 /* Skip P-frames if we do not have reference frame no valid header. */
2295 //                    if(s2->pict_type==P_TYPE && s2->first_field && !s2->first_slice) break;
2296                 }
2297                 /* Skip B-frames if we are in a hurry. */
2298                 if(avctx->hurry_up && s2->pict_type==B_TYPE) break;
2299                 if(  (avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type==B_TYPE)
2300                     ||(avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type!=I_TYPE)
2301                     || avctx->skip_frame >= AVDISCARD_ALL)
2302                     break;
2303                 /* Skip everything if we are in a hurry>=5. */
2304                 if(avctx->hurry_up>=5) break;
2305
2306                 if (!s->mpeg_enc_ctx_allocated) break;
2307
2308                 if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
2309                     if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2310                         break;
2311                 }
2312
2313                 if(s2->first_slice){
2314                     s2->first_slice=0;
2315                             if(mpeg_field_start(s2) < 0)
2316                         return -1;
2317                     }
2318                 if(!s2->current_picture_ptr){
2319                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2320                     return -1;
2321                 }
2322
2323                 if(avctx->thread_count > 1){
2324                     int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
2325                     if(threshold <= mb_y){
2326                         MpegEncContext *thread_context= s2->thread_context[s->slice_count];
2327
2328                         thread_context->start_mb_y= mb_y;
2329                         thread_context->end_mb_y  = s2->mb_height;
2330                         if(s->slice_count){
2331                             s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
2332                             ff_update_duplicate_context(thread_context, s2);
2333                         }
2334                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2335                         s->slice_count++;
2336                     }
2337                     buf_ptr += 2; //FIXME add minimum num of bytes per slice
2338                 }else{
2339                     ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
2340                     emms_c();
2341
2342                     if(ret < 0){
2343                         if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2344                             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);
2345                     }else{
2346                         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);
2347                     }
2348                 }
2349             }
2350             break;
2351         }
2352     }
2353 }
2354
2355 static int mpeg_decode_end(AVCodecContext *avctx)
2356 {
2357     Mpeg1Context *s = avctx->priv_data;
2358
2359     if (s->mpeg_enc_ctx_allocated)
2360         MPV_common_end(&s->mpeg_enc_ctx);
2361     return 0;
2362 }
2363
2364 AVCodec mpeg1video_decoder = {
2365     "mpeg1video",
2366     CODEC_TYPE_VIDEO,
2367     CODEC_ID_MPEG1VIDEO,
2368     sizeof(Mpeg1Context),
2369     mpeg_decode_init,
2370     NULL,
2371     mpeg_decode_end,
2372     mpeg_decode_frame,
2373     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2374     .flush= ff_mpeg_flush,
2375 };
2376
2377 AVCodec mpeg2video_decoder = {
2378     "mpeg2video",
2379     CODEC_TYPE_VIDEO,
2380     CODEC_ID_MPEG2VIDEO,
2381     sizeof(Mpeg1Context),
2382     mpeg_decode_init,
2383     NULL,
2384     mpeg_decode_end,
2385     mpeg_decode_frame,
2386     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2387     .flush= ff_mpeg_flush,
2388 };
2389
2390 //legacy decoder
2391 AVCodec mpegvideo_decoder = {
2392     "mpegvideo",
2393     CODEC_TYPE_VIDEO,
2394     CODEC_ID_MPEG2VIDEO,
2395     sizeof(Mpeg1Context),
2396     mpeg_decode_init,
2397     NULL,
2398     mpeg_decode_end,
2399     mpeg_decode_frame,
2400     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2401     .flush= ff_mpeg_flush,
2402 };
2403
2404 #ifdef HAVE_XVMC
2405 static int mpeg_mc_decode_init(AVCodecContext *avctx){
2406     Mpeg1Context *s;
2407
2408     if( avctx->thread_count > 1)
2409         return -1;
2410     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
2411         return -1;
2412     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
2413         dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2414     }
2415     mpeg_decode_init(avctx);
2416     s = avctx->priv_data;
2417
2418     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
2419     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
2420
2421     return 0;
2422 }
2423
2424 AVCodec mpeg_xvmc_decoder = {
2425     "mpegvideo_xvmc",
2426     CODEC_TYPE_VIDEO,
2427     CODEC_ID_MPEG2VIDEO_XVMC,
2428     sizeof(Mpeg1Context),
2429     mpeg_mc_decode_init,
2430     NULL,
2431     mpeg_decode_end,
2432     mpeg_decode_frame,
2433     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2434     .flush= ff_mpeg_flush,
2435 };
2436
2437 #endif
2438
2439 /* this is ugly i know, but the alternative is too make
2440    hundreds of vars global and prefix them with ff_mpeg1_
2441    which is far uglier. */
2442 #include "mdec.c"