lowres width/height cleanup 3rd try
[ffmpeg.git] / libavcodec / mpeg12.c
1 /*
2  * MPEG1 codec / MPEG2 decoder
3  * Copyright (c) 2000,2001 Fabrice Bellard.
4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> 
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20  
21 /**
22  * @file mpeg12.c
23  * MPEG1/2 codec
24  */
25  
26 //#define DEBUG
27 #include "avcodec.h"
28 #include "dsputil.h"
29 #include "mpegvideo.h"
30
31 #include "mpeg12data.h"
32
33 //#undef NDEBUG
34 //#include <assert.h>
35
36
37 /* Start codes. */
38 #define SEQ_END_CODE            0x000001b7
39 #define SEQ_START_CODE          0x000001b3
40 #define GOP_START_CODE          0x000001b8
41 #define PICTURE_START_CODE      0x00000100
42 #define SLICE_MIN_START_CODE    0x00000101
43 #define SLICE_MAX_START_CODE    0x000001af
44 #define EXT_START_CODE          0x000001b5
45 #define USER_START_CODE         0x000001b2
46
47 #define DC_VLC_BITS 9
48 #define MV_VLC_BITS 9
49 #define MBINCR_VLC_BITS 9
50 #define MB_PAT_VLC_BITS 9
51 #define MB_PTYPE_VLC_BITS 6
52 #define MB_BTYPE_VLC_BITS 6
53 #define TEX_VLC_BITS 9
54
55 #ifdef CONFIG_ENCODERS
56 static void mpeg1_encode_block(MpegEncContext *s, 
57                          DCTELEM *block, 
58                          int component);
59 static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code);    // RAL: f_code parameter added
60 #endif //CONFIG_ENCODERS
61 static inline int mpeg1_decode_block_inter(MpegEncContext *s, 
62                               DCTELEM *block, 
63                               int n);
64 static inline int mpeg1_decode_block_intra(MpegEncContext *s, 
65                               DCTELEM *block, 
66                               int n);
67 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
68 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, 
69                                         DCTELEM *block, 
70                                         int n);
71 static inline int mpeg2_decode_block_intra(MpegEncContext *s, 
72                                     DCTELEM *block, 
73                                     int n);
74 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
75 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
76 static void exchange_uv(MpegEncContext *s);
77
78 #ifdef HAVE_XVMC
79 extern int XVMC_field_start(MpegEncContext *s, AVCodecContext *avctx);
80 extern int XVMC_field_end(MpegEncContext *s);
81 extern void XVMC_pack_pblocks(MpegEncContext *s,int cbp);
82 extern void XVMC_init_block(MpegEncContext *s);//set s->block
83 #endif
84
85 const enum PixelFormat pixfmt_yuv_420[]= {PIX_FMT_YUV420P,-1};
86 const enum PixelFormat pixfmt_yuv_422[]= {PIX_FMT_YUV422P,-1};
87 const enum PixelFormat pixfmt_yuv_444[]= {PIX_FMT_YUV444P,-1};
88 const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
89                                            PIX_FMT_XVMC_MPEG2_IDCT,
90                                            PIX_FMT_XVMC_MPEG2_MC,
91                                            -1};
92 #ifdef CONFIG_ENCODERS
93 static uint8_t (*mv_penalty)[MAX_MV*2+1]= NULL;
94 static uint8_t fcode_tab[MAX_MV*2+1];
95
96 static uint32_t uni_mpeg1_ac_vlc_bits[64*64*2];
97 static uint8_t  uni_mpeg1_ac_vlc_len [64*64*2];
98
99 /* simple include everything table for dc, first byte is bits number next 3 are code*/
100 static uint32_t mpeg1_lum_dc_uni[512];
101 static uint32_t mpeg1_chr_dc_uni[512];
102
103 static uint8_t mpeg1_index_run[2][64];
104 static int8_t mpeg1_max_level[2][64];
105 #endif //CONFIG_ENCODERS
106
107 static void init_2d_vlc_rl(RLTable *rl)
108 {
109     int i;
110     
111     init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2, 
112              &rl->table_vlc[0][1], 4, 2,
113              &rl->table_vlc[0][0], 4, 2);
114
115     
116     rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
117     for(i=0; i<rl->vlc.table_size; i++){
118         int code= rl->vlc.table[i][0];
119         int len = rl->vlc.table[i][1];
120         int level, run;
121     
122         if(len==0){ // illegal code
123             run= 65;
124             level= MAX_LEVEL;
125         }else if(len<0){ //more bits needed
126             run= 0;
127             level= code;
128         }else{
129             if(code==rl->n){ //esc
130                 run= 65;
131                 level= 0;
132             }else if(code==rl->n+1){ //eob
133                 run= 0;
134                 level= 127;
135             }else{
136                 run=   rl->table_run  [code] + 1;
137                 level= rl->table_level[code];
138             }
139         }
140         rl->rl_vlc[0][i].len= len;
141         rl->rl_vlc[0][i].level= level;
142         rl->rl_vlc[0][i].run= run;
143     }
144 }
145
146 #ifdef CONFIG_ENCODERS
147 static void init_uni_ac_vlc(RLTable *rl, uint32_t *uni_ac_vlc_bits, uint8_t *uni_ac_vlc_len){
148     int i;
149
150     for(i=0; i<128; i++){
151         int level= i-64;
152         int run;
153         for(run=0; run<64; run++){
154             int len, bits, code;
155             
156             int alevel= ABS(level);
157             int sign= (level>>31)&1;
158
159             if (alevel > rl->max_level[0][run])
160                 code= 111; /*rl->n*/
161             else
162                 code= rl->index_run[0][run] + alevel - 1;
163
164             if (code < 111 /* rl->n */) {
165                 /* store the vlc & sign at once */
166                 len=   mpeg1_vlc[code][1]+1;
167                 bits= (mpeg1_vlc[code][0]<<1) + sign;
168             } else {
169                 len=  mpeg1_vlc[111/*rl->n*/][1]+6;
170                 bits= mpeg1_vlc[111/*rl->n*/][0]<<6;
171
172                 bits|= run;
173                 if (alevel < 128) {
174                     bits<<=8; len+=8;
175                     bits|= level & 0xff;
176                 } else {
177                     bits<<=16; len+=16;
178                     bits|= level & 0xff;
179                     if (level < 0) {
180                         bits|= 0x8001 + level + 255;
181                     } else {
182                         bits|= level & 0xffff;
183                     }
184                 }
185             }
186
187             uni_ac_vlc_bits[UNI_AC_ENC_INDEX(run, i)]= bits;
188             uni_ac_vlc_len [UNI_AC_ENC_INDEX(run, i)]= len;
189         }
190     }
191 }
192
193
194 static int find_frame_rate_index(MpegEncContext *s){
195     int i;
196     int64_t dmin= INT64_MAX;
197     int64_t d;
198
199     for(i=1;i<14;i++) {
200         int64_t n0= 1001LL/frame_rate_tab[i].den*frame_rate_tab[i].num*s->avctx->frame_rate_base;
201         int64_t n1= 1001LL*s->avctx->frame_rate;
202         if(s->avctx->strict_std_compliance >= 0 && i>=9) break;
203
204         d = ABS(n0 - n1);
205         if(d < dmin){
206             dmin=d;
207             s->frame_rate_index= i;
208         }
209     }
210     if(dmin)
211         return -1;
212     else
213         return 0;
214 }
215
216 static int encode_init(AVCodecContext *avctx)
217 {
218     MpegEncContext *s = avctx->priv_data;
219
220     if(MPV_encode_init(avctx) < 0)
221         return -1;
222
223     if(find_frame_rate_index(s) < 0){
224         if(s->strict_std_compliance >=0){
225             av_log(avctx, AV_LOG_ERROR, "MPEG1/2 doesnt support %d/%d fps\n", avctx->frame_rate, avctx->frame_rate_base);
226             return -1;
227         }else{
228             av_log(avctx, AV_LOG_INFO, "MPEG1/2 doesnt support %d/%d fps, there may be AV sync issues\n", avctx->frame_rate, avctx->frame_rate_base);
229         }
230     }
231     
232     return 0;
233 }
234
235 static void put_header(MpegEncContext *s, int header)
236 {
237     align_put_bits(&s->pb);
238     put_bits(&s->pb, 16, header>>16);
239     put_bits(&s->pb, 16, header&0xFFFF);
240 }
241
242 /* put sequence header if needed */
243 static void mpeg1_encode_sequence_header(MpegEncContext *s)
244 {
245         unsigned int vbv_buffer_size;
246         unsigned int fps, v;
247         int i;
248         uint64_t time_code;
249         float best_aspect_error= 1E10;
250         float aspect_ratio= av_q2d(s->avctx->sample_aspect_ratio);
251         int constraint_parameter_flag;
252         
253         if(aspect_ratio==0.0) aspect_ratio= 1.0; //pixel aspect 1:1 (VGA)
254         
255         if (s->current_picture.key_frame) {
256             AVRational framerate= frame_rate_tab[s->frame_rate_index];
257
258             /* mpeg1 header repeated every gop */
259             put_header(s, SEQ_START_CODE);
260  
261             put_bits(&s->pb, 12, s->width);
262             put_bits(&s->pb, 12, s->height);
263             
264             for(i=1; i<15; i++){
265                 float error= aspect_ratio;
266                 if(s->codec_id == CODEC_ID_MPEG1VIDEO || i <=1)
267                     error-= 1.0/mpeg1_aspect[i];
268                 else
269                     error-= av_q2d(mpeg2_aspect[i])*s->height/s->width;
270              
271                 error= ABS(error);
272                 
273                 if(error < best_aspect_error){
274                     best_aspect_error= error;
275                     s->aspect_ratio_info= i;
276                 }
277             }
278             
279             put_bits(&s->pb, 4, s->aspect_ratio_info);
280             put_bits(&s->pb, 4, s->frame_rate_index);
281             
282             if(s->avctx->rc_max_rate){
283                 v = (s->avctx->rc_max_rate + 399) / 400;
284                 if (v > 0x3ffff && s->codec_id == CODEC_ID_MPEG1VIDEO)
285                     v = 0x3ffff;
286             }else{
287                 v= 0x3FFFF;
288             }
289
290             if(s->avctx->rc_buffer_size)
291                 vbv_buffer_size = s->avctx->rc_buffer_size;
292             else
293                 /* VBV calculation: Scaled so that a VCD has the proper VBV size of 40 kilobytes */
294                 vbv_buffer_size = (( 20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024;
295             vbv_buffer_size= (vbv_buffer_size + 16383) / 16384;
296
297             put_bits(&s->pb, 18, v & 0x3FFFF);
298             put_bits(&s->pb, 1, 1); /* marker */
299             put_bits(&s->pb, 10, vbv_buffer_size & 0x3FF);
300
301             constraint_parameter_flag= 
302                 s->width <= 768 && s->height <= 576 && 
303                 s->mb_width * s->mb_height <= 396 &&
304                 s->mb_width * s->mb_height * framerate.num <= framerate.den*396*25 &&
305                 framerate.num <= framerate.den*30 &&
306                 vbv_buffer_size <= 20 &&
307                 v <= 1856000/400 &&
308                 s->codec_id == CODEC_ID_MPEG1VIDEO;
309                 
310             put_bits(&s->pb, 1, constraint_parameter_flag);
311             
312             ff_write_quant_matrix(&s->pb, s->avctx->intra_matrix);
313             ff_write_quant_matrix(&s->pb, s->avctx->inter_matrix);
314
315             if(s->codec_id == CODEC_ID_MPEG2VIDEO){
316                 put_header(s, EXT_START_CODE);
317                 put_bits(&s->pb, 4, 1); //seq ext
318                 put_bits(&s->pb, 1, 0); //esc
319                 
320                 if(s->avctx->profile == FF_PROFILE_UNKNOWN){
321                     put_bits(&s->pb, 3, 4); //profile
322                 }else{
323                     put_bits(&s->pb, 3, s->avctx->profile); //profile
324                 }
325
326                 if(s->avctx->level == FF_LEVEL_UNKNOWN){
327                     put_bits(&s->pb, 4, 8); //level
328                 }else{
329                     put_bits(&s->pb, 4, s->avctx->level); //level
330                 }
331
332                 put_bits(&s->pb, 1, s->progressive_sequence);
333                 put_bits(&s->pb, 2, 1); //chroma format 4:2:0
334                 put_bits(&s->pb, 2, 0); //horizontal size ext
335                 put_bits(&s->pb, 2, 0); //vertical size ext
336                 put_bits(&s->pb, 12, v>>18); //bitrate ext
337                 put_bits(&s->pb, 1, 1); //marker
338                 put_bits(&s->pb, 8, vbv_buffer_size >>10); //vbv buffer ext
339                 put_bits(&s->pb, 1, s->low_delay);
340                 put_bits(&s->pb, 2, 0); // frame_rate_ext_n
341                 put_bits(&s->pb, 5, 0); // frame_rate_ext_d
342             }
343             
344             put_header(s, GOP_START_CODE);
345             put_bits(&s->pb, 1, 0); /* do drop frame */
346             /* time code : we must convert from the real frame rate to a
347                fake mpeg frame rate in case of low frame rate */
348             fps = (framerate.num + framerate.den/2)/ framerate.den;
349             time_code = s->current_picture_ptr->coded_picture_number;
350
351             s->gop_picture_number = time_code;
352             put_bits(&s->pb, 5, (uint32_t)((time_code / (fps * 3600)) % 24));
353             put_bits(&s->pb, 6, (uint32_t)((time_code / (fps * 60)) % 60));
354             put_bits(&s->pb, 1, 1);
355             put_bits(&s->pb, 6, (uint32_t)((time_code / fps) % 60));
356             put_bits(&s->pb, 6, (uint32_t)((time_code % fps)));
357             put_bits(&s->pb, 1, !!(s->flags & CODEC_FLAG_CLOSED_GOP));
358             put_bits(&s->pb, 1, 0); /* broken link */
359         }
360 }
361
362 static inline void encode_mb_skip_run(MpegEncContext *s, int run){
363     while (run >= 33) {
364         put_bits(&s->pb, 11, 0x008);
365         run -= 33;
366     }
367     put_bits(&s->pb, mbAddrIncrTable[run][1], 
368              mbAddrIncrTable[run][0]);
369 }
370 #endif //CONFIG_ENCODERS
371
372 static void common_init(MpegEncContext *s)
373 {
374
375     s->y_dc_scale_table=
376     s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
377
378 }
379
380 void ff_mpeg1_clean_buffers(MpegEncContext *s){
381     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
382     s->last_dc[1] = s->last_dc[0];
383     s->last_dc[2] = s->last_dc[0];
384     memset(s->last_mv, 0, sizeof(s->last_mv));
385 }
386
387 #ifdef CONFIG_ENCODERS
388
389 void ff_mpeg1_encode_slice_header(MpegEncContext *s){
390     put_header(s, SLICE_MIN_START_CODE + s->mb_y);
391     put_bits(&s->pb, 5, s->qscale); /* quantizer scale */
392     put_bits(&s->pb, 1, 0); /* slice extra information */
393 }
394
395 void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
396 {
397     mpeg1_encode_sequence_header(s);
398
399     /* mpeg1 picture header */
400     put_header(s, PICTURE_START_CODE);
401     /* temporal reference */
402
403     // RAL: s->picture_number instead of s->fake_picture_number
404     put_bits(&s->pb, 10, (s->picture_number - 
405                           s->gop_picture_number) & 0x3ff); 
406     put_bits(&s->pb, 3, s->pict_type);
407
408     s->vbv_delay_ptr= s->pb.buf + put_bits_count(&s->pb)/8;
409     put_bits(&s->pb, 16, 0xFFFF); /* vbv_delay */
410     
411     // RAL: Forward f_code also needed for B frames
412     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
413         put_bits(&s->pb, 1, 0); /* half pel coordinates */
414         if(s->codec_id == CODEC_ID_MPEG1VIDEO)
415             put_bits(&s->pb, 3, s->f_code); /* forward_f_code */
416         else
417             put_bits(&s->pb, 3, 7); /* forward_f_code */
418     }
419     
420     // RAL: Backward f_code necessary for B frames
421     if (s->pict_type == B_TYPE) {
422         put_bits(&s->pb, 1, 0); /* half pel coordinates */
423         if(s->codec_id == CODEC_ID_MPEG1VIDEO)
424             put_bits(&s->pb, 3, s->b_code); /* backward_f_code */
425         else
426             put_bits(&s->pb, 3, 7); /* backward_f_code */
427     }
428
429     put_bits(&s->pb, 1, 0); /* extra bit picture */
430
431     s->frame_pred_frame_dct = 1;
432     if(s->codec_id == CODEC_ID_MPEG2VIDEO){
433         put_header(s, EXT_START_CODE);
434         put_bits(&s->pb, 4, 8); //pic ext
435         if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
436             put_bits(&s->pb, 4, s->f_code);
437             put_bits(&s->pb, 4, s->f_code);
438         }else{
439             put_bits(&s->pb, 8, 255);
440         }
441         if (s->pict_type == B_TYPE) {
442             put_bits(&s->pb, 4, s->b_code);
443             put_bits(&s->pb, 4, s->b_code);
444         }else{
445             put_bits(&s->pb, 8, 255);
446         }
447         put_bits(&s->pb, 2, s->intra_dc_precision);
448         
449         assert(s->picture_structure == PICT_FRAME);
450         put_bits(&s->pb, 2, s->picture_structure);
451         if (s->progressive_sequence) {
452             put_bits(&s->pb, 1, 0); /* no repeat */
453         } else {
454             put_bits(&s->pb, 1, s->current_picture_ptr->top_field_first);
455         }
456         /* XXX: optimize the generation of this flag with entropy
457            measures */
458         s->frame_pred_frame_dct = s->progressive_sequence;
459         
460         put_bits(&s->pb, 1, s->frame_pred_frame_dct);
461         put_bits(&s->pb, 1, s->concealment_motion_vectors);
462         put_bits(&s->pb, 1, s->q_scale_type);
463         put_bits(&s->pb, 1, s->intra_vlc_format);
464         put_bits(&s->pb, 1, s->alternate_scan);
465         put_bits(&s->pb, 1, s->repeat_first_field);
466         put_bits(&s->pb, 1, s->chroma_420_type=1);
467         s->progressive_frame = s->progressive_sequence;
468         put_bits(&s->pb, 1, s->progressive_frame);
469         put_bits(&s->pb, 1, 0); //composite_display_flag
470     }
471     if(s->flags & CODEC_FLAG_SVCD_SCAN_OFFSET){
472         int i;
473
474         put_header(s, USER_START_CODE);
475         for(i=0; i<sizeof(svcd_scan_offset_placeholder); i++){
476             put_bits(&s->pb, 8, svcd_scan_offset_placeholder[i]);
477         }
478     }
479     
480     s->mb_y=0;
481     ff_mpeg1_encode_slice_header(s);
482 }
483
484 static inline void put_mb_modes(MpegEncContext *s, int n, int bits, 
485                                 int has_mv, int field_motion)
486 {
487     put_bits(&s->pb, n, bits);
488     if (!s->frame_pred_frame_dct) {
489         if (has_mv) 
490             put_bits(&s->pb, 2, 2 - field_motion); /* motion_type: frame/field */
491         put_bits(&s->pb, 1, s->interlaced_dct);
492     }
493 }
494
495 void mpeg1_encode_mb(MpegEncContext *s,
496                      DCTELEM block[6][64],
497                      int motion_x, int motion_y)
498 {
499     int i, cbp;
500     const int mb_x = s->mb_x;
501     const int mb_y = s->mb_y;
502     const int first_mb= mb_x == s->resync_mb_x && mb_y == s->resync_mb_y;
503
504     /* compute cbp */
505     cbp = 0;
506     for(i=0;i<6;i++) {
507         if (s->block_last_index[i] >= 0)
508             cbp |= 1 << (5 - i);
509     }
510     
511     if (cbp == 0 && !first_mb && s->mv_type == MV_TYPE_16X16 &&
512         (mb_x != s->mb_width - 1 || (mb_y != s->mb_height - 1 && s->codec_id == CODEC_ID_MPEG1VIDEO)) && 
513         ((s->pict_type == P_TYPE && (motion_x | motion_y) == 0) ||
514         (s->pict_type == B_TYPE && s->mv_dir == s->last_mv_dir && (((s->mv_dir & MV_DIR_FORWARD) ? ((s->mv[0][0][0] - s->last_mv[0][0][0])|(s->mv[0][0][1] - s->last_mv[0][0][1])) : 0) |
515         ((s->mv_dir & MV_DIR_BACKWARD) ? ((s->mv[1][0][0] - s->last_mv[1][0][0])|(s->mv[1][0][1] - s->last_mv[1][0][1])) : 0)) == 0))) {
516         s->mb_skip_run++;
517         s->qscale -= s->dquant;
518         s->skip_count++;
519         s->misc_bits++;
520         s->last_bits++;
521         if(s->pict_type == P_TYPE){
522             s->last_mv[0][1][0]= s->last_mv[0][0][0]= 
523             s->last_mv[0][1][1]= s->last_mv[0][0][1]= 0;
524         }
525     } else {
526         if(first_mb){
527             assert(s->mb_skip_run == 0);
528             encode_mb_skip_run(s, s->mb_x);
529         }else{
530             encode_mb_skip_run(s, s->mb_skip_run);
531         }
532         
533         if (s->pict_type == I_TYPE) {
534             if(s->dquant && cbp){
535                 put_mb_modes(s, 2, 1, 0, 0); /* macroblock_type : macroblock_quant = 1 */
536                 put_bits(&s->pb, 5, s->qscale);
537             }else{
538                 put_mb_modes(s, 1, 1, 0, 0); /* macroblock_type : macroblock_quant = 0 */
539                 s->qscale -= s->dquant;
540             }
541             s->misc_bits+= get_bits_diff(s);
542             s->i_count++;
543         } else if (s->mb_intra) {
544             if(s->dquant && cbp){
545                 put_mb_modes(s, 6, 0x01, 0, 0);
546                 put_bits(&s->pb, 5, s->qscale);
547             }else{
548                 put_mb_modes(s, 5, 0x03, 0, 0);
549                 s->qscale -= s->dquant;
550             }
551             s->misc_bits+= get_bits_diff(s);
552             s->i_count++;
553             memset(s->last_mv, 0, sizeof(s->last_mv));
554         } else if (s->pict_type == P_TYPE) { 
555             if(s->mv_type == MV_TYPE_16X16){
556                 if (cbp != 0) {
557                     if ((motion_x|motion_y) == 0) {
558                         if(s->dquant){
559                             put_mb_modes(s, 5, 1, 0, 0); /* macroblock_pattern & quant */
560                             put_bits(&s->pb, 5, s->qscale);
561                         }else{
562                             put_mb_modes(s, 2, 1, 0, 0); /* macroblock_pattern only */
563                         }
564                         s->misc_bits+= get_bits_diff(s);
565                     } else {
566                         if(s->dquant){
567                             put_mb_modes(s, 5, 2, 1, 0); /* motion + cbp */
568                             put_bits(&s->pb, 5, s->qscale);
569                         }else{
570                             put_mb_modes(s, 1, 1, 1, 0); /* motion + cbp */
571                         }
572                         s->misc_bits+= get_bits_diff(s);
573                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
574                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
575                         s->mv_bits+= get_bits_diff(s);
576                     }
577                 } else {
578                     put_bits(&s->pb, 3, 1); /* motion only */
579                     if (!s->frame_pred_frame_dct)
580                         put_bits(&s->pb, 2, 2); /* motion_type: frame */
581                     s->misc_bits+= get_bits_diff(s);
582                     mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
583                     mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
584                     s->qscale -= s->dquant;
585                     s->mv_bits+= get_bits_diff(s);
586                 }
587                 s->last_mv[0][1][0]= s->last_mv[0][0][0]= motion_x;
588                 s->last_mv[0][1][1]= s->last_mv[0][0][1]= motion_y;
589             }else{
590                 assert(!s->frame_pred_frame_dct && s->mv_type == MV_TYPE_FIELD);
591
592                 if (cbp) {
593                     if(s->dquant){
594                         put_mb_modes(s, 5, 2, 1, 1); /* motion + cbp */
595                         put_bits(&s->pb, 5, s->qscale);
596                     }else{
597                         put_mb_modes(s, 1, 1, 1, 1); /* motion + cbp */
598                     }
599                 } else {
600                     put_bits(&s->pb, 3, 1); /* motion only */
601                     put_bits(&s->pb, 2, 1); /* motion_type: field */
602                     s->qscale -= s->dquant;
603                 }
604                 s->misc_bits+= get_bits_diff(s);
605                 for(i=0; i<2; i++){
606                     put_bits(&s->pb, 1, s->field_select[0][i]);
607                     mpeg1_encode_motion(s, s->mv[0][i][0] -  s->last_mv[0][i][0]    , s->f_code);
608                     mpeg1_encode_motion(s, s->mv[0][i][1] - (s->last_mv[0][i][1]>>1), s->f_code);
609                     s->last_mv[0][i][0]=   s->mv[0][i][0];
610                     s->last_mv[0][i][1]= 2*s->mv[0][i][1];
611                 }
612                 s->mv_bits+= get_bits_diff(s);
613             }
614             if(cbp)
615                 put_bits(&s->pb, mbPatTable[cbp][1], mbPatTable[cbp][0]);
616             s->f_count++;
617         } else{  
618             static const int mb_type_len[4]={0,3,4,2}; //bak,for,bi
619
620             if(s->mv_type == MV_TYPE_16X16){
621                 if (cbp){    // With coded bloc pattern
622                     if (s->dquant) {
623                         if(s->mv_dir == MV_DIR_FORWARD)
624                             put_mb_modes(s, 6, 3, 1, 0);
625                         else
626                             put_mb_modes(s, mb_type_len[s->mv_dir]+3, 2, 1, 0);
627                         put_bits(&s->pb, 5, s->qscale);
628                     } else {
629                         put_mb_modes(s, mb_type_len[s->mv_dir], 3, 1, 0);
630                     }
631                 }else{    // No coded bloc pattern
632                     put_bits(&s->pb, mb_type_len[s->mv_dir], 2);
633                     if (!s->frame_pred_frame_dct)
634                         put_bits(&s->pb, 2, 2); /* motion_type: frame */
635                     s->qscale -= s->dquant;
636                 }
637                 s->misc_bits += get_bits_diff(s);
638                 if (s->mv_dir&MV_DIR_FORWARD){
639                     mpeg1_encode_motion(s, s->mv[0][0][0] - s->last_mv[0][0][0], s->f_code); 
640                     mpeg1_encode_motion(s, s->mv[0][0][1] - s->last_mv[0][0][1], s->f_code); 
641                     s->last_mv[0][0][0]=s->last_mv[0][1][0]= s->mv[0][0][0];
642                     s->last_mv[0][0][1]=s->last_mv[0][1][1]= s->mv[0][0][1];
643                     s->f_count++;
644                 }
645                 if (s->mv_dir&MV_DIR_BACKWARD){
646                     mpeg1_encode_motion(s, s->mv[1][0][0] - s->last_mv[1][0][0], s->b_code); 
647                     mpeg1_encode_motion(s, s->mv[1][0][1] - s->last_mv[1][0][1], s->b_code); 
648                     s->last_mv[1][0][0]=s->last_mv[1][1][0]= s->mv[1][0][0];
649                     s->last_mv[1][0][1]=s->last_mv[1][1][1]= s->mv[1][0][1];
650                     s->b_count++;
651                 }
652             }else{
653                 assert(s->mv_type == MV_TYPE_FIELD);
654                 assert(!s->frame_pred_frame_dct);
655                 if (cbp){    // With coded bloc pattern
656                     if (s->dquant) {
657                         if(s->mv_dir == MV_DIR_FORWARD)
658                             put_mb_modes(s, 6, 3, 1, 1);
659                         else
660                             put_mb_modes(s, mb_type_len[s->mv_dir]+3, 2, 1, 1);
661                         put_bits(&s->pb, 5, s->qscale);
662                     } else {
663                         put_mb_modes(s, mb_type_len[s->mv_dir], 3, 1, 1);
664                     }
665                 }else{    // No coded bloc pattern
666                     put_bits(&s->pb, mb_type_len[s->mv_dir], 2);
667                     put_bits(&s->pb, 2, 1); /* motion_type: field */
668                     s->qscale -= s->dquant;
669                 }
670                 s->misc_bits += get_bits_diff(s);
671                 if (s->mv_dir&MV_DIR_FORWARD){
672                     for(i=0; i<2; i++){
673                         put_bits(&s->pb, 1, s->field_select[0][i]);
674                         mpeg1_encode_motion(s, s->mv[0][i][0] -  s->last_mv[0][i][0]    , s->f_code);
675                         mpeg1_encode_motion(s, s->mv[0][i][1] - (s->last_mv[0][i][1]>>1), s->f_code);
676                         s->last_mv[0][i][0]=   s->mv[0][i][0];
677                         s->last_mv[0][i][1]= 2*s->mv[0][i][1];
678                     }
679                     s->f_count++;
680                 }
681                 if (s->mv_dir&MV_DIR_BACKWARD){
682                     for(i=0; i<2; i++){
683                         put_bits(&s->pb, 1, s->field_select[1][i]);
684                         mpeg1_encode_motion(s, s->mv[1][i][0] -  s->last_mv[1][i][0]    , s->b_code);
685                         mpeg1_encode_motion(s, s->mv[1][i][1] - (s->last_mv[1][i][1]>>1), s->b_code);
686                         s->last_mv[1][i][0]=   s->mv[1][i][0];
687                         s->last_mv[1][i][1]= 2*s->mv[1][i][1];
688                     }
689                     s->b_count++;
690                 }
691             }
692             s->mv_bits += get_bits_diff(s);
693             if(cbp)
694                 put_bits(&s->pb, mbPatTable[cbp][1], mbPatTable[cbp][0]);
695         }
696         for(i=0;i<6;i++) {
697             if (cbp & (1 << (5 - i))) {
698                 mpeg1_encode_block(s, block[i], i);
699             }
700         }
701         s->mb_skip_run = 0;
702         if(s->mb_intra)
703             s->i_tex_bits+= get_bits_diff(s);
704         else
705             s->p_tex_bits+= get_bits_diff(s);
706     }
707 }
708
709 // RAL: Parameter added: f_or_b_code
710 static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code)
711 {
712     int code, bit_size, l, bits, range, sign;
713
714     if (val == 0) {
715         /* zero vector */
716         code = 0;
717         put_bits(&s->pb,
718                  mbMotionVectorTable[0][1], 
719                  mbMotionVectorTable[0][0]); 
720     } else {
721         bit_size = f_or_b_code - 1;
722         range = 1 << bit_size;
723         /* modulo encoding */
724         l= INT_BIT - 5 - bit_size;
725         val= (val<<l)>>l;
726
727         if (val >= 0) {
728             val--;
729             code = (val >> bit_size) + 1;
730             bits = val & (range - 1);
731             sign = 0;
732         } else {
733             val = -val;
734             val--;
735             code = (val >> bit_size) + 1;
736             bits = val & (range - 1);
737             sign = 1;
738         }
739
740         assert(code > 0 && code <= 16);
741
742         put_bits(&s->pb,
743                  mbMotionVectorTable[code][1], 
744                  mbMotionVectorTable[code][0]); 
745
746         put_bits(&s->pb, 1, sign);
747         if (bit_size > 0) {
748             put_bits(&s->pb, bit_size, bits);
749         }
750     }
751 }
752
753 void ff_mpeg1_encode_init(MpegEncContext *s)
754 {
755     static int done=0;
756
757     common_init(s);
758
759     if(!done){
760         int f_code;
761         int mv;
762         int i;
763
764         done=1;
765         init_rl(&rl_mpeg1);
766
767         for(i=0; i<64; i++)
768         {
769                 mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i];
770                 mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i];
771         }
772         
773         init_uni_ac_vlc(&rl_mpeg1, uni_mpeg1_ac_vlc_bits, uni_mpeg1_ac_vlc_len);
774
775         /* build unified dc encoding tables */
776         for(i=-255; i<256; i++)
777         {
778                 int adiff, index;
779                 int bits, code;
780                 int diff=i;
781
782                 adiff = ABS(diff);
783                 if(diff<0) diff--;
784                 index = av_log2(2*adiff);
785
786                 bits= vlc_dc_lum_bits[index] + index;
787                 code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1));
788                 mpeg1_lum_dc_uni[i+255]= bits + (code<<8);
789                 
790                 bits= vlc_dc_chroma_bits[index] + index;
791                 code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1));
792                 mpeg1_chr_dc_uni[i+255]= bits + (code<<8);
793         }
794
795         mv_penalty= av_mallocz( sizeof(uint8_t)*(MAX_FCODE+1)*(2*MAX_MV+1) );
796
797         for(f_code=1; f_code<=MAX_FCODE; f_code++){
798             for(mv=-MAX_MV; mv<=MAX_MV; mv++){
799                 int len;
800
801                 if(mv==0) len= mbMotionVectorTable[0][1];
802                 else{
803                     int val, bit_size, range, code;
804
805                     bit_size = f_code - 1;
806                     range = 1 << bit_size;
807
808                     val=mv;
809                     if (val < 0) 
810                         val = -val;
811                     val--;
812                     code = (val >> bit_size) + 1;
813                     if(code<17){
814                         len= mbMotionVectorTable[code][1] + 1 + bit_size;
815                     }else{
816                         len= mbMotionVectorTable[16][1] + 2 + bit_size;
817                     }
818                 }
819
820                 mv_penalty[f_code][mv+MAX_MV]= len;
821             }
822         }
823         
824
825         for(f_code=MAX_FCODE; f_code>0; f_code--){
826             for(mv=-(8<<f_code); mv<(8<<f_code); mv++){
827                 fcode_tab[mv+MAX_MV]= f_code;
828             }
829         }
830     }
831     s->me.mv_penalty= mv_penalty;
832     s->fcode_tab= fcode_tab;
833     if(s->codec_id == CODEC_ID_MPEG1VIDEO){
834         s->min_qcoeff=-255;
835         s->max_qcoeff= 255;
836     }else{
837         s->min_qcoeff=-2047;
838         s->max_qcoeff= 2047;
839     }
840     s->intra_ac_vlc_length=
841     s->inter_ac_vlc_length=
842     s->intra_ac_vlc_last_length=
843     s->inter_ac_vlc_last_length= uni_mpeg1_ac_vlc_len;
844 }
845
846 static inline void encode_dc(MpegEncContext *s, int diff, int component)
847 {
848   if(((unsigned) (diff+255)) >= 511){
849         int index;
850
851         if(diff<0){
852             index= av_log2_16bit(-2*diff);
853             diff--;
854         }else{
855             index= av_log2_16bit(2*diff);
856         }
857         if (component == 0) {
858             put_bits(
859                 &s->pb, 
860                 vlc_dc_lum_bits[index] + index,
861                 (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1)));
862         }else{
863             put_bits(
864                 &s->pb, 
865                 vlc_dc_chroma_bits[index] + index,
866                 (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1)));
867         }
868   }else{
869     if (component == 0) {
870         put_bits(
871             &s->pb, 
872             mpeg1_lum_dc_uni[diff+255]&0xFF,
873             mpeg1_lum_dc_uni[diff+255]>>8);
874     } else {
875         put_bits(
876             &s->pb, 
877             mpeg1_chr_dc_uni[diff+255]&0xFF,
878             mpeg1_chr_dc_uni[diff+255]>>8);
879     }
880   }
881 }
882
883 static void mpeg1_encode_block(MpegEncContext *s, 
884                                DCTELEM *block, 
885                                int n)
886 {
887     int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign;
888     int code, component;
889 //    RLTable *rl = &rl_mpeg1;
890
891     last_index = s->block_last_index[n];
892
893     /* DC coef */
894     if (s->mb_intra) {
895         component = (n <= 3 ? 0 : n - 4 + 1);
896         dc = block[0]; /* overflow is impossible */
897         diff = dc - s->last_dc[component];
898         encode_dc(s, diff, component);
899         s->last_dc[component] = dc;
900         i = 1;
901 /*
902         if (s->intra_vlc_format)
903             rl = &rl_mpeg2;
904         else
905             rl = &rl_mpeg1;
906 */
907     } else {
908         /* encode the first coefficient : needs to be done here because
909            it is handled slightly differently */
910         level = block[0];
911         if (abs(level) == 1) {
912                 code = ((uint32_t)level >> 31); /* the sign bit */
913                 put_bits(&s->pb, 2, code | 0x02);
914                 i = 1;
915         } else {
916             i = 0;
917             last_non_zero = -1;
918             goto next_coef;
919         }
920     }
921
922     /* now quantify & encode AC coefs */
923     last_non_zero = i - 1;
924
925     for(;i<=last_index;i++) {
926         j = s->intra_scantable.permutated[i];
927         level = block[j];
928     next_coef:
929 #if 0
930         if (level != 0)
931             dprintf("level[%d]=%d\n", i, level);
932 #endif            
933         /* encode using VLC */
934         if (level != 0) {
935             run = i - last_non_zero - 1;
936             
937             alevel= level;
938             MASK_ABS(sign, alevel)
939             sign&=1;
940
941 //            code = get_rl_index(rl, 0, run, alevel);
942             if (alevel <= mpeg1_max_level[0][run]){
943                 code= mpeg1_index_run[0][run] + alevel - 1;
944                 /* store the vlc & sign at once */
945                 put_bits(&s->pb, mpeg1_vlc[code][1]+1, (mpeg1_vlc[code][0]<<1) + sign);
946             } else {
947                 /* escape seems to be pretty rare <5% so i dont optimize it */
948                 put_bits(&s->pb, mpeg1_vlc[111/*rl->n*/][1], mpeg1_vlc[111/*rl->n*/][0]);
949                 /* escape: only clip in this case */
950                 put_bits(&s->pb, 6, run);
951                 if(s->codec_id == CODEC_ID_MPEG1VIDEO){
952                     if (alevel < 128) {
953                         put_bits(&s->pb, 8, level & 0xff);
954                     } else {
955                         if (level < 0) {
956                             put_bits(&s->pb, 16, 0x8001 + level + 255);
957                         } else {
958                             put_bits(&s->pb, 16, level & 0xffff);
959                         }
960                     }
961                 }else{
962                     put_bits(&s->pb, 12, level & 0xfff);
963                 }
964             }
965             last_non_zero = i;
966         }
967     }
968     /* end of block */
969     put_bits(&s->pb, 2, 0x2);
970 }
971 #endif //CONFIG_ENCODERS
972
973 /******************************************/
974 /* decoding */
975
976 static VLC dc_lum_vlc;
977 static VLC dc_chroma_vlc;
978 static VLC mv_vlc;
979 static VLC mbincr_vlc;
980 static VLC mb_ptype_vlc;
981 static VLC mb_btype_vlc;
982 static VLC mb_pat_vlc;
983
984 static void init_vlcs(void)
985 {
986     static int done = 0;
987
988     if (!done) {
989         done = 1;
990
991         init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12, 
992                  vlc_dc_lum_bits, 1, 1,
993                  vlc_dc_lum_code, 2, 2);
994         init_vlc(&dc_chroma_vlc,  DC_VLC_BITS, 12, 
995                  vlc_dc_chroma_bits, 1, 1,
996                  vlc_dc_chroma_code, 2, 2);
997         init_vlc(&mv_vlc, MV_VLC_BITS, 17, 
998                  &mbMotionVectorTable[0][1], 2, 1,
999                  &mbMotionVectorTable[0][0], 2, 1);
1000         init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36, 
1001                  &mbAddrIncrTable[0][1], 2, 1,
1002                  &mbAddrIncrTable[0][0], 2, 1);
1003         init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
1004                  &mbPatTable[0][1], 2, 1,
1005                  &mbPatTable[0][0], 2, 1);
1006         
1007         init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7, 
1008                  &table_mb_ptype[0][1], 2, 1,
1009                  &table_mb_ptype[0][0], 2, 1);
1010         init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11, 
1011                  &table_mb_btype[0][1], 2, 1,
1012                  &table_mb_btype[0][0], 2, 1);
1013         init_rl(&rl_mpeg1);
1014         init_rl(&rl_mpeg2);
1015
1016         init_2d_vlc_rl(&rl_mpeg1);
1017         init_2d_vlc_rl(&rl_mpeg2);
1018     }
1019 }
1020
1021 static inline int get_dmv(MpegEncContext *s)
1022 {
1023     if(get_bits1(&s->gb)) 
1024         return 1 - (get_bits1(&s->gb) << 1);
1025     else
1026         return 0;
1027 }
1028
1029 static inline int get_qscale(MpegEncContext *s)
1030 {
1031     int qscale = get_bits(&s->gb, 5);
1032     if (s->q_scale_type) {
1033         return non_linear_qscale[qscale];
1034     } else {
1035         return qscale << 1;
1036     }
1037 }
1038
1039 /* motion type (for mpeg2) */
1040 #define MT_FIELD 1
1041 #define MT_FRAME 2
1042 #define MT_16X8  2
1043 #define MT_DMV   3
1044
1045 static int mpeg_decode_mb(MpegEncContext *s,
1046                           DCTELEM block[12][64])
1047 {
1048     int i, j, k, cbp, val, mb_type, motion_type;
1049     const int mb_block_count = 4 + (1<< s->chroma_format)
1050
1051     dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
1052
1053     assert(s->mb_skiped==0);
1054
1055     if (s->mb_skip_run-- != 0) {
1056         if(s->pict_type == I_TYPE){
1057             av_log(s->avctx, AV_LOG_ERROR, "skiped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1058             return -1;
1059         }
1060     
1061         /* skip mb */
1062         s->mb_intra = 0;
1063         for(i=0;i<12;i++)
1064             s->block_last_index[i] = -1;
1065         if(s->picture_structure == PICT_FRAME)
1066             s->mv_type = MV_TYPE_16X16;
1067         else
1068             s->mv_type = MV_TYPE_FIELD;
1069         if (s->pict_type == P_TYPE) {
1070             /* if P type, zero motion vector is implied */
1071             s->mv_dir = MV_DIR_FORWARD;
1072             s->mv[0][0][0] = s->mv[0][0][1] = 0;
1073             s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1074             s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1075             s->field_select[0][0]= s->picture_structure - 1;
1076             s->mb_skiped = 1;
1077             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
1078         } else {
1079             /* if B type, reuse previous vectors and directions */
1080             s->mv[0][0][0] = s->last_mv[0][0][0];
1081             s->mv[0][0][1] = s->last_mv[0][0][1];
1082             s->mv[1][0][0] = s->last_mv[1][0][0];
1083             s->mv[1][0][1] = s->last_mv[1][0][1];
1084
1085             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= 
1086                 s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1] | MB_TYPE_SKIP;
1087 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
1088
1089             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0) 
1090                 s->mb_skiped = 1;
1091         }
1092
1093         return 0;
1094     }
1095
1096     switch(s->pict_type) {
1097     default:
1098     case I_TYPE:
1099         if (get_bits1(&s->gb) == 0) {
1100             if (get_bits1(&s->gb) == 0){
1101                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
1102                 return -1;
1103             }
1104             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
1105         } else {
1106             mb_type = MB_TYPE_INTRA;
1107         }
1108         break;
1109     case P_TYPE:
1110         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
1111         if (mb_type < 0){
1112             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
1113             return -1;
1114         }
1115         mb_type = ptype2mb_type[ mb_type ];
1116         break;
1117     case B_TYPE:
1118         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
1119         if (mb_type < 0){
1120             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
1121             return -1;
1122         }
1123         mb_type = btype2mb_type[ mb_type ];
1124         break;
1125     }
1126     dprintf("mb_type=%x\n", mb_type);
1127 //    motion_type = 0; /* avoid warning */
1128     if (IS_INTRA(mb_type)) {
1129         /* compute dct type */
1130         if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1131             !s->frame_pred_frame_dct) {
1132             s->interlaced_dct = get_bits1(&s->gb);
1133         }
1134
1135         if (IS_QUANT(mb_type))
1136             s->qscale = get_qscale(s);
1137         
1138         if (s->concealment_motion_vectors) {
1139             /* just parse them */
1140             if (s->picture_structure != PICT_FRAME) 
1141                 skip_bits1(&s->gb); /* field select */
1142             
1143             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] = 
1144                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
1145             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] = 
1146                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
1147
1148             skip_bits1(&s->gb); /* marker */
1149         }else
1150             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
1151         s->mb_intra = 1;
1152 #ifdef HAVE_XVMC
1153         //one 1 we memcpy blocks in xvmcvideo
1154         if(s->avctx->xvmc_acceleration > 1){
1155             XVMC_pack_pblocks(s,-1);//inter are always full blocks
1156             if(s->swap_uv){
1157                 exchange_uv(s);
1158             }
1159         }
1160 #endif
1161
1162         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
1163             for(i=0;i<mb_block_count;i++) {
1164                 if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
1165                     return -1;
1166             }
1167         } else {
1168             for(i=0;i<6;i++) {
1169                 if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
1170                     return -1;
1171             }
1172         }
1173     } else {
1174         if (mb_type & MB_TYPE_ZERO_MV){
1175             assert(mb_type & MB_TYPE_CBP);
1176
1177             /* compute dct type */
1178             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1179                 !s->frame_pred_frame_dct) {
1180                 s->interlaced_dct = get_bits1(&s->gb);
1181             }
1182
1183             if (IS_QUANT(mb_type))
1184                 s->qscale = get_qscale(s);
1185
1186             s->mv_dir = MV_DIR_FORWARD;
1187             if(s->picture_structure == PICT_FRAME)
1188                 s->mv_type = MV_TYPE_16X16;
1189             else{
1190                 s->mv_type = MV_TYPE_FIELD;
1191                 mb_type |= MB_TYPE_INTERLACED;
1192                 s->field_select[0][0]= s->picture_structure - 1;
1193             }
1194             s->last_mv[0][0][0] = 0;
1195             s->last_mv[0][0][1] = 0;
1196             s->last_mv[0][1][0] = 0;
1197             s->last_mv[0][1][1] = 0;
1198             s->mv[0][0][0] = 0;
1199             s->mv[0][0][1] = 0;
1200         }else{
1201             assert(mb_type & MB_TYPE_L0L1);
1202 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
1203             /* get additionnal motion vector type */
1204             if (s->frame_pred_frame_dct) 
1205                 motion_type = MT_FRAME;
1206             else{
1207                 motion_type = get_bits(&s->gb, 2);
1208             }
1209
1210             /* compute dct type */
1211             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1212                 !s->frame_pred_frame_dct && HAS_CBP(mb_type)) {
1213                 s->interlaced_dct = get_bits1(&s->gb);
1214             }
1215
1216             if (IS_QUANT(mb_type))
1217                 s->qscale = get_qscale(s);
1218
1219             /* motion vectors */
1220             s->mv_dir = 0;
1221             for(i=0;i<2;i++) {
1222                 if (USES_LIST(mb_type, i)) {
1223                     s->mv_dir |= (MV_DIR_FORWARD >> i);
1224                     dprintf("motion_type=%d\n", motion_type);
1225                     switch(motion_type) {
1226                     case MT_FRAME: /* or MT_16X8 */
1227                         if (s->picture_structure == PICT_FRAME) {
1228                             /* MT_FRAME */
1229                             mb_type |= MB_TYPE_16x16; 
1230                             s->mv_type = MV_TYPE_16X16;
1231                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] = 
1232                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
1233                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] = 
1234                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
1235                             /* full_pel: only for mpeg1 */
1236                             if (s->full_pel[i]){
1237                                 s->mv[i][0][0] <<= 1;
1238                                 s->mv[i][0][1] <<= 1;
1239                             }
1240                         } else {
1241                             /* MT_16X8 */
1242                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED; 
1243                             s->mv_type = MV_TYPE_16X8;
1244                             for(j=0;j<2;j++) {
1245                                 s->field_select[i][j] = get_bits1(&s->gb);
1246                                 for(k=0;k<2;k++) {
1247                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1248                                                              s->last_mv[i][j][k]);
1249                                     s->last_mv[i][j][k] = val;
1250                                     s->mv[i][j][k] = val;
1251                                 }
1252                             }
1253                         }
1254                         break;
1255                     case MT_FIELD:
1256                         s->mv_type = MV_TYPE_FIELD;
1257                         if (s->picture_structure == PICT_FRAME) {
1258                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED; 
1259                             for(j=0;j<2;j++) {
1260                                 s->field_select[i][j] = get_bits1(&s->gb);
1261                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1262                                                          s->last_mv[i][j][0]);
1263                                 s->last_mv[i][j][0] = val;
1264                                 s->mv[i][j][0] = val;
1265                                 dprintf("fmx=%d\n", val);
1266                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1267                                                          s->last_mv[i][j][1] >> 1);
1268                                 s->last_mv[i][j][1] = val << 1;
1269                                 s->mv[i][j][1] = val;
1270                                 dprintf("fmy=%d\n", val);
1271                             }
1272                         } else {
1273                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED; 
1274                             s->field_select[i][0] = get_bits1(&s->gb);
1275                             for(k=0;k<2;k++) {
1276                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1277                                                          s->last_mv[i][0][k]);
1278                                 s->last_mv[i][0][k] = val;
1279                                 s->last_mv[i][1][k] = val;
1280                                 s->mv[i][0][k] = val;
1281                             }
1282                         }
1283                         break;
1284                     case MT_DMV:
1285                         {
1286                             int dmx, dmy, mx, my, m;
1287
1288                             mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0], 
1289                                                     s->last_mv[i][0][0]);
1290                             s->last_mv[i][0][0] = mx;
1291                             s->last_mv[i][1][0] = mx;
1292                             dmx = get_dmv(s);
1293                             my = mpeg_decode_motion(s, s->mpeg_f_code[i][1], 
1294                                                     s->last_mv[i][0][1] >> 1);
1295                             dmy = get_dmv(s);
1296                             s->mv_type = MV_TYPE_DMV;
1297
1298
1299                             s->last_mv[i][0][1] = my<<1;
1300                             s->last_mv[i][1][1] = my<<1;
1301
1302                             s->mv[i][0][0] = mx;
1303                             s->mv[i][0][1] = my;
1304                             s->mv[i][1][0] = mx;//not used
1305                             s->mv[i][1][1] = my;//not used
1306
1307                             if (s->picture_structure == PICT_FRAME) {
1308                                 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED; 
1309
1310                                 //m = 1 + 2 * s->top_field_first;
1311                                 m = s->top_field_first ? 1 : 3;
1312
1313                                 /* top -> top pred */
1314                                 s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1315                                 s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1316                                 m = 4 - m;
1317                                 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1318                                 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1319                             } else {
1320                                 mb_type |= MB_TYPE_16x16;
1321
1322                                 s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1323                                 s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1324                                 if(s->picture_structure == PICT_TOP_FIELD)
1325                                     s->mv[i][2][1]--;
1326                                 else 
1327                                     s->mv[i][2][1]++;
1328                             }
1329                         }
1330                         break;
1331                     default:
1332                         av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1333                         return -1;
1334                     }
1335                 }
1336             }
1337         }
1338         
1339         s->mb_intra = 0;
1340
1341         if (HAS_CBP(mb_type)) {
1342             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1343             if (cbp < 0 || ((cbp == 0) && (s->chroma_format < 2)) ){
1344                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1345                 return -1;
1346             }
1347             if(mb_block_count > 6){
1348                  cbp<<= mb_block_count-6;
1349                  cbp |= get_bits(&s->gb, mb_block_count-6);
1350             }
1351
1352 #ifdef HAVE_XVMC
1353             //on 1 we memcpy blocks in xvmcvideo
1354             if(s->avctx->xvmc_acceleration > 1){
1355                 XVMC_pack_pblocks(s,cbp);
1356                 if(s->swap_uv){
1357                     exchange_uv(s);
1358                 }
1359             }    
1360 #endif
1361
1362             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
1363                 if(s->flags2 & CODEC_FLAG2_FAST){
1364                     for(i=0;i<6;i++) {
1365                         if(cbp & 32) {
1366                             mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);
1367                         } else {
1368                             s->block_last_index[i] = -1;
1369                         }
1370                         cbp+=cbp;
1371                     }
1372                 }else{
1373                     cbp<<= 12-mb_block_count;
1374     
1375                     for(i=0;i<mb_block_count;i++) {
1376                         if ( cbp & (1<<11) ) {
1377                             if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
1378                                 return -1;
1379                         } else {
1380                             s->block_last_index[i] = -1;
1381                         }
1382                         cbp+=cbp;
1383                     }
1384                 }
1385             } else {
1386                 if(s->flags2 & CODEC_FLAG2_FAST){
1387                     for(i=0;i<6;i++) {
1388                         if (cbp & 32) {
1389                             mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);
1390                         } else {
1391                             s->block_last_index[i] = -1;
1392                         }
1393                         cbp+=cbp;
1394                     }
1395                 }else{
1396                     for(i=0;i<6;i++) {
1397                         if (cbp & 32) {
1398                             if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)
1399                                 return -1;
1400                         } else {
1401                             s->block_last_index[i] = -1;
1402                         }
1403                         cbp+=cbp;
1404                     }
1405                 }
1406             }
1407         }else{
1408             for(i=0;i<6;i++)
1409                 s->block_last_index[i] = -1;
1410         }
1411     }
1412
1413     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
1414
1415     return 0;
1416 }
1417
1418 /* as h263, but only 17 codes */
1419 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
1420 {
1421     int code, sign, val, l, shift;
1422
1423     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
1424     if (code == 0) {
1425         return pred;
1426     }
1427     if (code < 0) {
1428         return 0xffff;
1429     }
1430
1431     sign = get_bits1(&s->gb);
1432     shift = fcode - 1;
1433     val = code;
1434     if (shift) {
1435         val = (val - 1) << shift;
1436         val |= get_bits(&s->gb, shift);
1437         val++;
1438     }
1439     if (sign)
1440         val = -val;
1441     val += pred;
1442     
1443     /* modulo decoding */
1444     l= INT_BIT - 5 - shift;
1445     val = (val<<l)>>l;
1446     return val;
1447 }
1448
1449 static inline int decode_dc(GetBitContext *gb, int component)
1450 {
1451     int code, diff;
1452
1453     if (component == 0) {
1454         code = get_vlc2(gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
1455     } else {
1456         code = get_vlc2(gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
1457     }
1458     if (code < 0){
1459         av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
1460         return 0xffff;
1461     }
1462     if (code == 0) {
1463         diff = 0;
1464     } else {
1465         diff = get_xbits(gb, code);
1466     }
1467     return diff;
1468 }
1469
1470 static inline int mpeg1_decode_block_intra(MpegEncContext *s, 
1471                                DCTELEM *block, 
1472                                int n)
1473 {
1474     int level, dc, diff, i, j, run;
1475     int component;
1476     RLTable *rl = &rl_mpeg1;
1477     uint8_t * const scantable= s->intra_scantable.permutated;
1478     const uint16_t *quant_matrix= s->intra_matrix;
1479     const int qscale= s->qscale;
1480
1481     /* DC coef */
1482     component = (n <= 3 ? 0 : n - 4 + 1);
1483     diff = decode_dc(&s->gb, component);
1484     if (diff >= 0xffff)
1485         return -1;
1486     dc = s->last_dc[component];
1487     dc += diff;
1488     s->last_dc[component] = dc;
1489     block[0] = dc<<3;
1490     dprintf("dc=%d diff=%d\n", dc, diff);
1491     i = 0;
1492     {
1493         OPEN_READER(re, &s->gb);    
1494         /* now quantify & encode AC coefs */
1495         for(;;) {
1496             UPDATE_CACHE(re, &s->gb);
1497             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1498             
1499             if(level == 127){
1500                 break;
1501             } else if(level != 0) {
1502                 i += run;
1503                 j = scantable[i];
1504                 level= (level*qscale*quant_matrix[j])>>4;
1505                 level= (level-1)|1;
1506                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1507                 LAST_SKIP_BITS(re, &s->gb, 1);
1508             } else {
1509                 /* escape */
1510                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1511                 UPDATE_CACHE(re, &s->gb);
1512                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1513                 if (level == -128) {
1514                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1515                 } else if (level == 0) {
1516                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1517                 }
1518                 i += run;
1519                 j = scantable[i];
1520                 if(level<0){
1521                     level= -level;
1522                     level= (level*qscale*quant_matrix[j])>>4;
1523                     level= (level-1)|1;
1524                     level= -level;
1525                 }else{
1526                     level= (level*qscale*quant_matrix[j])>>4;
1527                     level= (level-1)|1;
1528                 }
1529             }
1530             if (i > 63){
1531                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1532                 return -1;
1533             }
1534
1535             block[j] = level;
1536         }
1537         CLOSE_READER(re, &s->gb);
1538     }
1539     s->block_last_index[n] = i;
1540    return 0;
1541 }
1542
1543 static inline int mpeg1_decode_block_inter(MpegEncContext *s, 
1544                                DCTELEM *block, 
1545                                int n)
1546 {
1547     int level, i, j, run;
1548     RLTable *rl = &rl_mpeg1;
1549     uint8_t * const scantable= s->intra_scantable.permutated;
1550     const uint16_t *quant_matrix= s->inter_matrix;
1551     const int qscale= s->qscale;
1552
1553     {
1554         int v;
1555         OPEN_READER(re, &s->gb);
1556         i = -1;
1557         /* special case for the first coef. no need to add a second vlc table */
1558         UPDATE_CACHE(re, &s->gb);
1559         v= SHOW_UBITS(re, &s->gb, 2);
1560         if (v & 2) {
1561             LAST_SKIP_BITS(re, &s->gb, 2);
1562             level= (3*qscale*quant_matrix[0])>>5;
1563             level= (level-1)|1;
1564             if(v&1)
1565                 level= -level;
1566             block[0] = level;
1567             i++;
1568         }
1569
1570         /* now quantify & encode AC coefs */
1571         for(;;) {
1572             UPDATE_CACHE(re, &s->gb);
1573             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1574             
1575             if(level == 127){
1576                 break;
1577             } else if(level != 0) {
1578                 i += run;
1579                 j = scantable[i];
1580                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1581                 level= (level-1)|1;
1582                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1583                 LAST_SKIP_BITS(re, &s->gb, 1);
1584             } else {
1585                 /* escape */
1586                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1587                 UPDATE_CACHE(re, &s->gb);
1588                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1589                 if (level == -128) {
1590                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1591                 } else if (level == 0) {
1592                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1593                 }
1594                 i += run;
1595                 j = scantable[i];
1596                 if(level<0){
1597                     level= -level;
1598                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1599                     level= (level-1)|1;
1600                     level= -level;
1601                 }else{
1602                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1603                     level= (level-1)|1;
1604                 }
1605             }
1606             if (i > 63){
1607                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1608                 return -1;
1609             }
1610
1611             block[j] = level;
1612         }
1613         CLOSE_READER(re, &s->gb);
1614     }
1615     s->block_last_index[n] = i;
1616     return 0;
1617 }
1618
1619 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
1620 {
1621     int level, i, j, run;
1622     RLTable *rl = &rl_mpeg1;
1623     uint8_t * const scantable= s->intra_scantable.permutated;
1624     const int qscale= s->qscale;
1625
1626     {
1627         int v;
1628         OPEN_READER(re, &s->gb);
1629         i = -1;
1630         /* special case for the first coef. no need to add a second vlc table */
1631         UPDATE_CACHE(re, &s->gb);
1632         v= SHOW_UBITS(re, &s->gb, 2);
1633         if (v & 2) {
1634             LAST_SKIP_BITS(re, &s->gb, 2);
1635             level= (3*qscale)>>1;
1636             level= (level-1)|1;
1637             if(v&1)
1638                 level= -level;
1639             block[0] = level;
1640             i++;
1641         }
1642
1643         /* now quantify & encode AC coefs */
1644         for(;;) {
1645             UPDATE_CACHE(re, &s->gb);
1646             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1647             
1648             if(level == 127){
1649                 break;
1650             } else if(level != 0) {
1651                 i += run;
1652                 j = scantable[i];
1653                 level= ((level*2+1)*qscale)>>1;
1654                 level= (level-1)|1;
1655                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1656                 LAST_SKIP_BITS(re, &s->gb, 1);
1657             } else {
1658                 /* escape */
1659                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1660                 UPDATE_CACHE(re, &s->gb);
1661                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1662                 if (level == -128) {
1663                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1664                 } else if (level == 0) {
1665                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1666                 }
1667                 i += run;
1668                 j = scantable[i];
1669                 if(level<0){
1670                     level= -level;
1671                     level= ((level*2+1)*qscale)>>1;
1672                     level= (level-1)|1;
1673                     level= -level;
1674                 }else{
1675                     level= ((level*2+1)*qscale)>>1;
1676                     level= (level-1)|1;
1677                 }
1678             }
1679
1680             block[j] = level;
1681         }
1682         CLOSE_READER(re, &s->gb);
1683     }
1684     s->block_last_index[n] = i;
1685     return 0;
1686 }
1687
1688
1689 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, 
1690                                DCTELEM *block, 
1691                                int n)
1692 {
1693     int level, i, j, run;
1694     RLTable *rl = &rl_mpeg1;
1695     uint8_t * const scantable= s->intra_scantable.permutated;
1696     const uint16_t *quant_matrix;
1697     const int qscale= s->qscale;
1698     int mismatch;
1699
1700     mismatch = 1;
1701
1702     {
1703         int v;
1704         OPEN_READER(re, &s->gb);
1705         i = -1;
1706         if (n < 4)
1707             quant_matrix = s->inter_matrix;
1708         else
1709             quant_matrix = s->chroma_inter_matrix;
1710
1711         /* special case for the first coef. no need to add a second vlc table */
1712         UPDATE_CACHE(re, &s->gb);
1713         v= SHOW_UBITS(re, &s->gb, 2);
1714         if (v & 2) {
1715             LAST_SKIP_BITS(re, &s->gb, 2);
1716             level= (3*qscale*quant_matrix[0])>>5;
1717             if(v&1)
1718                 level= -level;
1719             block[0] = level;
1720             mismatch ^= level;
1721             i++;
1722         }
1723
1724         /* now quantify & encode AC coefs */
1725         for(;;) {
1726             UPDATE_CACHE(re, &s->gb);
1727             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1728             
1729             if(level == 127){
1730                 break;
1731             } else if(level != 0) {
1732                 i += run;
1733                 j = scantable[i];
1734                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1735                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1736                 LAST_SKIP_BITS(re, &s->gb, 1);
1737             } else {
1738                 /* escape */
1739                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1740                 UPDATE_CACHE(re, &s->gb);
1741                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1742
1743                 i += run;
1744                 j = scantable[i];
1745                 if(level<0){
1746                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
1747                     level= -level;
1748                 }else{
1749                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1750                 }
1751             }
1752             if (i > 63){
1753                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1754                 return -1;
1755             }
1756             
1757             mismatch ^= level;
1758             block[j] = level;
1759         }
1760         CLOSE_READER(re, &s->gb);
1761     }
1762     block[63] ^= (mismatch & 1);
1763     
1764     s->block_last_index[n] = i;
1765     return 0;
1766 }
1767
1768 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, 
1769                                DCTELEM *block, 
1770                                int n)
1771 {
1772     int level, i, j, run;
1773     RLTable *rl = &rl_mpeg1;
1774     uint8_t * const scantable= s->intra_scantable.permutated;
1775     const int qscale= s->qscale;
1776     int v;
1777     OPEN_READER(re, &s->gb);
1778     i = -1;
1779
1780     /* special case for the first coef. no need to add a second vlc table */
1781     UPDATE_CACHE(re, &s->gb);
1782     v= SHOW_UBITS(re, &s->gb, 2);
1783     if (v & 2) {
1784         LAST_SKIP_BITS(re, &s->gb, 2);
1785         level= (3*qscale)>>1;
1786         if(v&1)
1787             level= -level;
1788         block[0] = level;
1789         i++;
1790     }
1791
1792     /* now quantify & encode AC coefs */
1793     for(;;) {
1794         UPDATE_CACHE(re, &s->gb);
1795         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1796         
1797         if(level == 127){
1798             break;
1799         } else if(level != 0) {
1800             i += run;
1801             j = scantable[i];
1802             level= ((level*2+1)*qscale)>>1;
1803             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1804             LAST_SKIP_BITS(re, &s->gb, 1);
1805         } else {
1806             /* escape */
1807             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1808             UPDATE_CACHE(re, &s->gb);
1809             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1810
1811             i += run;
1812             j = scantable[i];
1813             if(level<0){
1814                 level= ((-level*2+1)*qscale)>>1;
1815                 level= -level;
1816             }else{
1817                 level= ((level*2+1)*qscale)>>1;
1818             }
1819         }
1820         
1821         block[j] = level;
1822     }
1823     CLOSE_READER(re, &s->gb);
1824     s->block_last_index[n] = i;
1825     return 0;
1826 }
1827
1828
1829 static inline int mpeg2_decode_block_intra(MpegEncContext *s, 
1830                                DCTELEM *block, 
1831                                int n)
1832 {
1833     int level, dc, diff, i, j, run;
1834     int component;
1835     RLTable *rl;
1836     uint8_t * const scantable= s->intra_scantable.permutated;
1837     const uint16_t *quant_matrix;
1838     const int qscale= s->qscale;
1839     int mismatch;
1840
1841     /* DC coef */
1842     if (n < 4){
1843         quant_matrix = s->intra_matrix;
1844         component = 0; 
1845     }else{
1846         quant_matrix = s->chroma_intra_matrix;
1847         component = (n&1) + 1;
1848     }
1849     diff = decode_dc(&s->gb, component);
1850     if (diff >= 0xffff)
1851         return -1;
1852     dc = s->last_dc[component];
1853     dc += diff;
1854     s->last_dc[component] = dc;
1855     block[0] = dc << (3 - s->intra_dc_precision);
1856     dprintf("dc=%d\n", block[0]);
1857     mismatch = block[0] ^ 1;
1858     i = 0;
1859     if (s->intra_vlc_format)
1860         rl = &rl_mpeg2;
1861     else
1862         rl = &rl_mpeg1;
1863
1864     {
1865         OPEN_READER(re, &s->gb);    
1866         /* now quantify & encode AC coefs */
1867         for(;;) {
1868             UPDATE_CACHE(re, &s->gb);
1869             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1870             
1871             if(level == 127){
1872                 break;
1873             } else if(level != 0) {
1874                 i += run;
1875                 j = scantable[i];
1876                 level= (level*qscale*quant_matrix[j])>>4;
1877                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1878                 LAST_SKIP_BITS(re, &s->gb, 1);
1879             } else {
1880                 /* escape */
1881                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1882                 UPDATE_CACHE(re, &s->gb);
1883                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1884                 i += run;
1885                 j = scantable[i];
1886                 if(level<0){
1887                     level= (-level*qscale*quant_matrix[j])>>4;
1888                     level= -level;
1889                 }else{
1890                     level= (level*qscale*quant_matrix[j])>>4;
1891                 }
1892             }
1893             if (i > 63){
1894                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1895                 return -1;
1896             }
1897             
1898             mismatch^= level;
1899             block[j] = level;
1900         }
1901         CLOSE_READER(re, &s->gb);
1902     }
1903     block[63]^= mismatch&1;
1904     
1905     s->block_last_index[n] = i;
1906     return 0;
1907 }
1908
1909 typedef struct Mpeg1Context {
1910     MpegEncContext mpeg_enc_ctx;
1911     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1912     int repeat_field; /* true if we must repeat the field */
1913     AVPanScan pan_scan; /** some temporary storage for the panscan */
1914     int slice_count;
1915     int swap_uv;//indicate VCR2
1916     int save_aspect_info;
1917     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1918
1919 } Mpeg1Context;
1920
1921 static int mpeg_decode_init(AVCodecContext *avctx)
1922 {
1923     Mpeg1Context *s = avctx->priv_data;
1924     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1925     int i;
1926     
1927     //we need some parmutation to store
1928     //matrixes, until MPV_common_init()
1929     //set the real permutatuon 
1930     for(i=0;i<64;i++)
1931        s2->dsp.idct_permutation[i]=i;
1932
1933     MPV_decode_defaults(s2);
1934     
1935     s->mpeg_enc_ctx.avctx= avctx;
1936     s->mpeg_enc_ctx.flags= avctx->flags;
1937     s->mpeg_enc_ctx.flags2= avctx->flags2;
1938     common_init(&s->mpeg_enc_ctx);
1939     init_vlcs();
1940
1941     s->mpeg_enc_ctx_allocated = 0;
1942     s->mpeg_enc_ctx.picture_number = 0;
1943     s->repeat_field = 0;
1944     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1945     return 0;
1946 }
1947
1948 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm, 
1949                                      const uint8_t *new_perm){
1950     uint16_t temp_matrix[64];
1951     int i;
1952
1953     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1954     
1955     for(i=0;i<64;i++){
1956         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1957     }      
1958 }
1959
1960 //Call this function when we know all parameters
1961 //it may be called in different places for mpeg1 and mpeg2
1962 static int mpeg_decode_postinit(AVCodecContext *avctx){
1963     Mpeg1Context *s1 = avctx->priv_data;
1964     MpegEncContext *s = &s1->mpeg_enc_ctx;
1965     uint8_t old_permutation[64];
1966
1967     if (
1968         (s1->mpeg_enc_ctx_allocated == 0)|| 
1969         avctx->coded_width  != s->width ||
1970         avctx->coded_height != s->height||
1971 //      s1->save_aspect_info != avctx->aspect_ratio_info||
1972         0)
1973     {
1974     
1975         if (s1->mpeg_enc_ctx_allocated) {
1976             MPV_common_end(s);
1977         }
1978
1979         if( (s->width == 0 )||(s->height == 0))
1980             return -2;
1981
1982         avcodec_set_dimensions(avctx, s->width, s->height);
1983         avctx->bit_rate = s->bit_rate;
1984         s1->save_aspect_info = s->aspect_ratio_info;
1985
1986      //low_delay may be forced, in this case we will have B frames
1987      //that behave like P frames
1988         avctx->has_b_frames = !(s->low_delay);
1989
1990         if(avctx->sub_id==1){//s->codec_id==avctx->codec_id==CODEC_ID
1991             //mpeg1 fps
1992             avctx->frame_rate     = frame_rate_tab[s->frame_rate_index].num;
1993             avctx->frame_rate_base= frame_rate_tab[s->frame_rate_index].den;
1994             //mpeg1 aspect
1995             avctx->sample_aspect_ratio= av_d2q(
1996                     1.0/mpeg1_aspect[s->aspect_ratio_info], 255);
1997
1998         }else{//mpeg2
1999         //mpeg2 fps
2000             av_reduce(
2001                 &s->avctx->frame_rate, 
2002                 &s->avctx->frame_rate_base, 
2003                 frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
2004                 frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
2005                 1<<30);
2006         //mpeg2 aspect
2007             if(s->aspect_ratio_info > 1){
2008                 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) ){
2009                     s->avctx->sample_aspect_ratio= 
2010                         av_div_q(
2011                          mpeg2_aspect[s->aspect_ratio_info], 
2012                          (AVRational){s->width, s->height}
2013                          );
2014                 }else{
2015                     s->avctx->sample_aspect_ratio= 
2016                         av_div_q(
2017                          mpeg2_aspect[s->aspect_ratio_info], 
2018                          (AVRational){s1->pan_scan.width, s1->pan_scan.height}
2019                         );
2020                 }
2021             }else{
2022                 s->avctx->sample_aspect_ratio= 
2023                     mpeg2_aspect[s->aspect_ratio_info];
2024             }
2025         }//mpeg2
2026
2027         if(avctx->xvmc_acceleration){
2028             avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
2029         }else{
2030             if(s->chroma_format <  2){
2031                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
2032             }else
2033             if(s->chroma_format == 2){
2034                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_422);
2035             }else
2036             if(s->chroma_format >  2){
2037                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_444);
2038             }
2039         }
2040         //until then pix_fmt may be changed right after codec init
2041         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
2042             if( avctx->idct_algo == FF_IDCT_AUTO )
2043                 avctx->idct_algo = FF_IDCT_SIMPLE;
2044
2045         //quantization matrixes may need reordering 
2046         //if dct permutation is changed
2047         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
2048
2049         if (MPV_common_init(s) < 0)
2050             return -2;
2051
2052         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
2053         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
2054         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
2055         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
2056
2057         s1->mpeg_enc_ctx_allocated = 1;
2058     }
2059     return 0;
2060 }
2061
2062 /* return the 8 bit start code value and update the search
2063    state. Return -1 if no start code found */
2064 static int find_start_code(const uint8_t **pbuf_ptr, const uint8_t *buf_end)
2065 {
2066     const uint8_t *buf_ptr= *pbuf_ptr;
2067
2068     buf_ptr++; //gurantees that -1 is within the array
2069     buf_end -= 2; // gurantees that +2 is within the array
2070
2071     while (buf_ptr < buf_end) {
2072         if(*buf_ptr==0){
2073             while(buf_ptr < buf_end && buf_ptr[1]==0)
2074                 buf_ptr++;
2075
2076             if(buf_ptr[-1] == 0 && buf_ptr[1] == 1){
2077                 *pbuf_ptr = buf_ptr+3;
2078                 return buf_ptr[2] + 0x100;
2079             }
2080         }
2081         buf_ptr += 2;
2082     }
2083     buf_end += 2; //undo the hack above
2084     
2085     *pbuf_ptr = buf_end;
2086     return -1;
2087 }
2088
2089 static int mpeg1_decode_picture(AVCodecContext *avctx, 
2090                                 const uint8_t *buf, int buf_size)
2091 {
2092     Mpeg1Context *s1 = avctx->priv_data;
2093     MpegEncContext *s = &s1->mpeg_enc_ctx;
2094     int ref, f_code, vbv_delay;
2095
2096     if(mpeg_decode_postinit(s->avctx) < 0) 
2097        return -2;
2098
2099     init_get_bits(&s->gb, buf, buf_size*8);
2100
2101     ref = get_bits(&s->gb, 10); /* temporal ref */
2102     s->pict_type = get_bits(&s->gb, 3);
2103
2104     vbv_delay= get_bits(&s->gb, 16);
2105     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
2106         s->full_pel[0] = get_bits1(&s->gb);
2107         f_code = get_bits(&s->gb, 3);
2108         if (f_code == 0)
2109             return -1;
2110         s->mpeg_f_code[0][0] = f_code;
2111         s->mpeg_f_code[0][1] = f_code;
2112     }
2113     if (s->pict_type == B_TYPE) {
2114         s->full_pel[1] = get_bits1(&s->gb);
2115         f_code = get_bits(&s->gb, 3);
2116         if (f_code == 0)
2117             return -1;
2118         s->mpeg_f_code[1][0] = f_code;
2119         s->mpeg_f_code[1][1] = f_code;
2120     }
2121     s->current_picture.pict_type= s->pict_type;
2122     s->current_picture.key_frame= s->pict_type == I_TYPE;
2123     
2124 //    if(avctx->debug & FF_DEBUG_PICT_INFO)
2125 //        av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d\n", vbv_delay, ref);
2126     
2127     s->y_dc_scale = 8;
2128     s->c_dc_scale = 8;
2129     s->first_slice = 1;
2130     return 0;
2131 }
2132
2133 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
2134 {
2135     MpegEncContext *s= &s1->mpeg_enc_ctx;
2136     int horiz_size_ext, vert_size_ext;
2137     int bit_rate_ext;
2138
2139     skip_bits(&s->gb, 1); /* profil and level esc*/
2140     s->avctx->profile= get_bits(&s->gb, 3);
2141     s->avctx->level= get_bits(&s->gb, 4);
2142     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
2143     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
2144     horiz_size_ext = get_bits(&s->gb, 2);
2145     vert_size_ext = get_bits(&s->gb, 2);
2146     s->width |= (horiz_size_ext << 12);
2147     s->height |= (vert_size_ext << 12);
2148     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
2149     s->bit_rate += (bit_rate_ext << 12) * 400;
2150     skip_bits1(&s->gb); /* marker */
2151     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
2152
2153     s->low_delay = get_bits1(&s->gb);
2154     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2155
2156     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
2157     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
2158
2159     dprintf("sequence extension\n");
2160     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2161     s->avctx->sub_id = 2; /* indicates mpeg2 found */
2162
2163     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2164         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n", 
2165                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
2166
2167 }
2168
2169 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
2170 {
2171     MpegEncContext *s= &s1->mpeg_enc_ctx;
2172     int color_description, w, h;
2173
2174     skip_bits(&s->gb, 3); /* video format */
2175     color_description= get_bits1(&s->gb);
2176     if(color_description){
2177         skip_bits(&s->gb, 8); /* color primaries */
2178         skip_bits(&s->gb, 8); /* transfer_characteristics */
2179         skip_bits(&s->gb, 8); /* matrix_coefficients */
2180     }
2181     w= get_bits(&s->gb, 14);
2182     skip_bits(&s->gb, 1); //marker
2183     h= get_bits(&s->gb, 14);
2184     skip_bits(&s->gb, 1); //marker
2185     
2186     s1->pan_scan.width= 16*w;
2187     s1->pan_scan.height=16*h;
2188         
2189     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2190         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
2191 }
2192
2193 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
2194 {
2195     MpegEncContext *s= &s1->mpeg_enc_ctx;
2196     int i,nofco;
2197
2198     nofco = 1;
2199     if(s->progressive_sequence){
2200         if(s->repeat_first_field){
2201             nofco++;
2202             if(s->top_field_first)
2203                 nofco++;        
2204         }
2205     }else{
2206         if(s->picture_structure == PICT_FRAME){
2207             nofco++;
2208             if(s->repeat_first_field)
2209                 nofco++;
2210         }
2211     }
2212     for(i=0; i<nofco; i++){
2213         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
2214         skip_bits(&s->gb, 1); //marker
2215         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
2216         skip_bits(&s->gb, 1); //marker
2217     }
2218    
2219     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2220         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n", 
2221             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1], 
2222             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1], 
2223             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
2224         );
2225 }
2226
2227 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
2228 {
2229     int i, v, j;
2230
2231     dprintf("matrix extension\n");
2232
2233     if (get_bits1(&s->gb)) {
2234         for(i=0;i<64;i++) {
2235             v = get_bits(&s->gb, 8);
2236             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2237             s->intra_matrix[j] = v;
2238             s->chroma_intra_matrix[j] = v;
2239         }
2240     }
2241     if (get_bits1(&s->gb)) {
2242         for(i=0;i<64;i++) {
2243             v = get_bits(&s->gb, 8);
2244             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2245             s->inter_matrix[j] = v;
2246             s->chroma_inter_matrix[j] = v;
2247         }
2248     }
2249     if (get_bits1(&s->gb)) {
2250         for(i=0;i<64;i++) {
2251             v = get_bits(&s->gb, 8);
2252             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2253             s->chroma_intra_matrix[j] = v;
2254         }
2255     }
2256     if (get_bits1(&s->gb)) {
2257         for(i=0;i<64;i++) {
2258             v = get_bits(&s->gb, 8);
2259             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2260             s->chroma_inter_matrix[j] = v;
2261         }
2262     }
2263 }
2264
2265 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
2266 {
2267     s->full_pel[0] = s->full_pel[1] = 0;
2268     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
2269     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
2270     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
2271     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
2272     s->intra_dc_precision = get_bits(&s->gb, 2);
2273     s->picture_structure = get_bits(&s->gb, 2);
2274     s->top_field_first = get_bits1(&s->gb);
2275     s->frame_pred_frame_dct = get_bits1(&s->gb);
2276     s->concealment_motion_vectors = get_bits1(&s->gb);
2277     s->q_scale_type = get_bits1(&s->gb);
2278     s->intra_vlc_format = get_bits1(&s->gb);
2279     s->alternate_scan = get_bits1(&s->gb);
2280     s->repeat_first_field = get_bits1(&s->gb);
2281     s->chroma_420_type = get_bits1(&s->gb);
2282     s->progressive_frame = get_bits1(&s->gb);
2283
2284     if(s->picture_structure == PICT_FRAME)
2285         s->first_field=0;
2286     else{
2287         s->first_field ^= 1;
2288         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
2289     }
2290     
2291     if(s->alternate_scan){
2292         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
2293         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
2294     }else{
2295         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
2296         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
2297     }
2298     
2299     /* composite display not parsed */
2300     dprintf("intra_dc_precision=%d\n", s->intra_dc_precision);
2301     dprintf("picture_structure=%d\n", s->picture_structure);
2302     dprintf("top field first=%d\n", s->top_field_first);
2303     dprintf("repeat first field=%d\n", s->repeat_first_field);
2304     dprintf("conceal=%d\n", s->concealment_motion_vectors);
2305     dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
2306     dprintf("alternate_scan=%d\n", s->alternate_scan);
2307     dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
2308     dprintf("progressive_frame=%d\n", s->progressive_frame);
2309 }
2310
2311 static void mpeg_decode_extension(AVCodecContext *avctx, 
2312                                   const uint8_t *buf, int buf_size)
2313 {
2314     Mpeg1Context *s1 = avctx->priv_data;
2315     MpegEncContext *s = &s1->mpeg_enc_ctx;
2316     int ext_type;
2317
2318     init_get_bits(&s->gb, buf, buf_size*8);
2319     
2320     ext_type = get_bits(&s->gb, 4);
2321     switch(ext_type) {
2322     case 0x1:
2323         mpeg_decode_sequence_extension(s1);
2324         break;
2325     case 0x2:
2326         mpeg_decode_sequence_display_extension(s1);
2327         break;
2328     case 0x3:
2329         mpeg_decode_quant_matrix_extension(s);
2330         break;
2331     case 0x7:
2332         mpeg_decode_picture_display_extension(s1);
2333         break;
2334     case 0x8:
2335         mpeg_decode_picture_coding_extension(s);
2336         break;
2337     }
2338 }
2339
2340 static void exchange_uv(MpegEncContext *s){
2341     short * tmp = s->pblocks[4];
2342     s->pblocks[4] = s->pblocks[5];
2343     s->pblocks[5] = tmp;
2344 }
2345
2346 static int mpeg_field_start(MpegEncContext *s){
2347     AVCodecContext *avctx= s->avctx;
2348     Mpeg1Context *s1 = (Mpeg1Context*)s;
2349
2350     /* start frame decoding */
2351     if(s->first_field || s->picture_structure==PICT_FRAME){
2352         if(MPV_frame_start(s, avctx) < 0)
2353             return -1;
2354
2355         ff_er_frame_start(s);
2356
2357         /* first check if we must repeat the frame */
2358         s->current_picture_ptr->repeat_pict = 0;
2359         if (s->repeat_first_field) {
2360             if (s->progressive_sequence) {
2361                 if (s->top_field_first)
2362                     s->current_picture_ptr->repeat_pict = 4;
2363                 else
2364                     s->current_picture_ptr->repeat_pict = 2;
2365             } else if (s->progressive_frame) {
2366                 s->current_picture_ptr->repeat_pict = 1;
2367             }
2368         }         
2369
2370         *s->current_picture_ptr->pan_scan= s1->pan_scan;
2371     }else{ //second field
2372             int i;
2373             
2374             if(!s->current_picture_ptr){
2375                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
2376                 return -1;
2377             }
2378             
2379             for(i=0; i<4; i++){
2380                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
2381                 if(s->picture_structure == PICT_BOTTOM_FIELD){
2382                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
2383                 } 
2384             }
2385     }
2386 #ifdef HAVE_XVMC
2387 // MPV_frame_start will call this function too,
2388 // but we need to call it on every field
2389     if(s->avctx->xvmc_acceleration)
2390          XVMC_field_start(s,avctx);
2391 #endif
2392
2393     return 0;
2394 }
2395
2396 #define DECODE_SLICE_ERROR -1
2397 #define DECODE_SLICE_OK 0
2398
2399 /**
2400  * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
2401  * @return DECODE_SLICE_ERROR if the slice is damaged<br>
2402  *         DECODE_SLICE_OK if this slice is ok<br>
2403  */
2404 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
2405                              const uint8_t **buf, int buf_size)
2406 {
2407     MpegEncContext *s = &s1->mpeg_enc_ctx;
2408     AVCodecContext *avctx= s->avctx;
2409     int ret;
2410     const int field_pic= s->picture_structure != PICT_FRAME;
2411     const int lowres= s->avctx->lowres;
2412
2413     s->resync_mb_x=
2414     s->resync_mb_y= -1;
2415
2416     if (mb_y<<field_pic >= s->mb_height){
2417         av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
2418         return -1;
2419     }
2420     
2421     init_get_bits(&s->gb, *buf, buf_size*8);
2422
2423     ff_mpeg1_clean_buffers(s);
2424     s->interlaced_dct = 0;
2425
2426     s->qscale = get_qscale(s);
2427
2428     if(s->qscale == 0){
2429         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
2430         return -1;
2431     }
2432     
2433     /* extra slice info */
2434     while (get_bits1(&s->gb) != 0) {
2435         skip_bits(&s->gb, 8);
2436     }
2437     
2438     s->mb_x=0;
2439
2440     for(;;) {
2441         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
2442         if (code < 0){
2443             av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
2444             return -1;
2445         }
2446         if (code >= 33) {
2447             if (code == 33) {
2448                 s->mb_x += 33;
2449             }
2450             /* otherwise, stuffing, nothing to do */
2451         } else {
2452             s->mb_x += code;
2453             break;
2454         }
2455     }
2456
2457     s->resync_mb_x= s->mb_x;
2458     s->resync_mb_y= s->mb_y= mb_y;
2459     s->mb_skip_run= 0;
2460     ff_init_block_index(s);
2461
2462     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
2463         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
2464              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", 
2465                  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],
2466                  s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")), 
2467                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"", 
2468                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
2469                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
2470         }
2471     }    
2472     
2473     for(;;) {
2474 #ifdef HAVE_XVMC
2475         //one 1 we memcpy blocks in xvmcvideo
2476         if(s->avctx->xvmc_acceleration > 1)
2477             XVMC_init_block(s);//set s->block
2478 #endif
2479
2480         s->dsp.clear_blocks(s->block[0]);
2481         if(!s->chroma_y_shift){
2482             s->dsp.clear_blocks(s->block[6]);
2483         }
2484         ret = mpeg_decode_mb(s, s->block);
2485         s->chroma_qscale= s->qscale;
2486
2487         dprintf("ret=%d\n", ret);
2488         if (ret < 0)
2489             return -1;
2490
2491         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
2492             const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
2493             int xy = s->mb_x*2 + s->mb_y*2*wrap;
2494             int motion_x, motion_y, dir, i;
2495             if(field_pic && !s->first_field)
2496                 xy += wrap/2;
2497
2498             for(i=0; i<2; i++){
2499                 for(dir=0; dir<2; dir++){
2500                     if (s->mb_intra || (dir==1 && s->pict_type != B_TYPE)) {
2501                         motion_x = motion_y = 0;
2502                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
2503                         motion_x = s->mv[dir][0][0];
2504                         motion_y = s->mv[dir][0][1];
2505                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
2506                         motion_x = s->mv[dir][i][0];
2507                         motion_y = s->mv[dir][i][1];
2508                     }
2509
2510                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
2511                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
2512                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
2513                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
2514                     s->current_picture.ref_index [dir][xy    ]=
2515                     s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
2516                 }
2517                 xy += wrap;
2518             }
2519         }
2520
2521         s->dest[0] += 16 >> lowres;
2522         s->dest[1] += 16 >> (s->chroma_x_shift + lowres);
2523         s->dest[2] += 16 >> (s->chroma_x_shift + lowres);
2524
2525         MPV_decode_mb(s, s->block);
2526         
2527         if (++s->mb_x >= s->mb_width) {
2528             const int mb_size= 16>>s->avctx->lowres;
2529
2530             ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
2531
2532             s->mb_x = 0;
2533             s->mb_y++;
2534
2535             if(s->mb_y<<field_pic >= s->mb_height){
2536                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
2537
2538                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)))
2539                    || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
2540                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d\n", left);
2541                     return -1;
2542                 }else
2543                     goto eos;
2544             }
2545             
2546             ff_init_block_index(s);
2547         }
2548
2549         /* skip mb handling */
2550         if (s->mb_skip_run == -1) {
2551             /* read again increment */
2552             s->mb_skip_run = 0;
2553             for(;;) {
2554                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
2555                 if (code < 0){
2556                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
2557                     return -1;
2558                 }
2559                 if (code >= 33) {
2560                     if (code == 33) {
2561                         s->mb_skip_run += 33;
2562                     }else if(code == 35){
2563                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
2564                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
2565                             return -1;
2566                         }
2567                         goto eos; /* end of slice */
2568                     }
2569                     /* otherwise, stuffing, nothing to do */
2570                 } else {
2571                     s->mb_skip_run += code;
2572                     break;
2573                 }
2574             }
2575         }
2576     }
2577 eos: // end of slice
2578     *buf += get_bits_count(&s->gb)/8 - 1;
2579 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
2580     return 0;
2581 }
2582
2583 static int slice_decode_thread(AVCodecContext *c, void *arg){
2584     MpegEncContext *s= arg;
2585     const uint8_t *buf= s->gb.buffer;
2586     int mb_y= s->start_mb_y;
2587
2588     s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
2589
2590     for(;;){
2591         int start_code, ret;
2592
2593         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
2594         emms_c();
2595 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n", 
2596 //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);
2597         if(ret < 0){
2598             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
2599                 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);
2600         }else{
2601             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);
2602         }
2603         
2604         if(s->mb_y == s->end_mb_y)
2605             return 0;
2606         
2607         start_code = find_start_code(&buf, s->gb.buffer_end);
2608         mb_y= start_code - SLICE_MIN_START_CODE;
2609         if(mb_y < 0 || mb_y >= s->end_mb_y)
2610             return -1;
2611     }
2612     
2613     return 0; //not reached
2614 }
2615
2616 /**
2617  * handles slice ends.
2618  * @return 1 if it seems to be the last slice of 
2619  */
2620 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2621 {
2622     Mpeg1Context *s1 = avctx->priv_data;
2623     MpegEncContext *s = &s1->mpeg_enc_ctx;
2624        
2625     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2626         return 0;
2627
2628 #ifdef HAVE_XVMC
2629     if(s->avctx->xvmc_acceleration)
2630         XVMC_field_end(s);
2631 #endif
2632     /* end of slice reached */
2633     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
2634         /* end of image */
2635
2636         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
2637
2638         ff_er_frame_end(s);
2639
2640         MPV_frame_end(s);
2641
2642         if (s->pict_type == B_TYPE || s->low_delay) {
2643             *pict= *(AVFrame*)s->current_picture_ptr;
2644             ff_print_debug_info(s, pict);
2645         } else {
2646             s->picture_number++;
2647             /* latency of 1 frame for I and P frames */
2648             /* XXX: use another variable than picture_number */
2649             if (s->last_picture_ptr != NULL) {
2650                 *pict= *(AVFrame*)s->last_picture_ptr;
2651                  ff_print_debug_info(s, pict);
2652             }
2653         }
2654
2655         return 1;
2656     } else {
2657         return 0;
2658     }
2659 }
2660
2661 static int mpeg1_decode_sequence(AVCodecContext *avctx, 
2662                                  const uint8_t *buf, int buf_size)
2663 {
2664     Mpeg1Context *s1 = avctx->priv_data;
2665     MpegEncContext *s = &s1->mpeg_enc_ctx;
2666     int width,height;
2667     int i, v, j;
2668
2669     init_get_bits(&s->gb, buf, buf_size*8);
2670
2671     width = get_bits(&s->gb, 12);
2672     height = get_bits(&s->gb, 12);
2673     if (width <= 0 || height <= 0 ||
2674         (width % 2) != 0 || (height % 2) != 0)
2675         return -1;
2676     s->aspect_ratio_info= get_bits(&s->gb, 4);
2677     if (s->aspect_ratio_info == 0)
2678         return -1;
2679     s->frame_rate_index = get_bits(&s->gb, 4);
2680     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
2681         return -1;
2682     s->bit_rate = get_bits(&s->gb, 18) * 400;
2683     if (get_bits1(&s->gb) == 0) /* marker */
2684         return -1;
2685     s->width = width;
2686     s->height = height;
2687
2688     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
2689     skip_bits(&s->gb, 1);
2690
2691     /* get matrix */
2692     if (get_bits1(&s->gb)) {
2693         for(i=0;i<64;i++) {
2694             v = get_bits(&s->gb, 8);
2695             if(v==0){
2696                 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
2697                 return -1;
2698             }
2699             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2700             s->intra_matrix[j] = v;
2701             s->chroma_intra_matrix[j] = v;
2702         }
2703 #ifdef DEBUG
2704         dprintf("intra matrix present\n");
2705         for(i=0;i<64;i++)
2706             dprintf(" %d", s->intra_matrix[s->dsp.idct_permutation[i]);
2707         printf("\n");
2708 #endif
2709     } else {
2710         for(i=0;i<64;i++) {
2711             j = s->dsp.idct_permutation[i];
2712             v = ff_mpeg1_default_intra_matrix[i];
2713             s->intra_matrix[j] = v;
2714             s->chroma_intra_matrix[j] = v;
2715         }
2716     }
2717     if (get_bits1(&s->gb)) {
2718         for(i=0;i<64;i++) {
2719             v = get_bits(&s->gb, 8);
2720             if(v==0){
2721                 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
2722                 return -1;
2723             }
2724             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2725             s->inter_matrix[j] = v;
2726             s->chroma_inter_matrix[j] = v;
2727         }
2728 #ifdef DEBUG
2729         dprintf("non intra matrix present\n");
2730         for(i=0;i<64;i++)
2731             dprintf(" %d", s->inter_matrix[s->dsp.idct_permutation[i]);
2732         printf("\n");
2733 #endif
2734     } else {
2735         for(i=0;i<64;i++) {
2736             int j= s->dsp.idct_permutation[i];
2737             v = ff_mpeg1_default_non_intra_matrix[i];
2738             s->inter_matrix[j] = v;
2739             s->chroma_inter_matrix[j] = v;
2740         }
2741     }
2742     
2743     if(show_bits(&s->gb, 23) != 0){
2744         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2745         return -1;
2746     }
2747
2748     /* we set mpeg2 parameters so that it emulates mpeg1 */
2749     s->progressive_sequence = 1;
2750     s->progressive_frame = 1;
2751     s->picture_structure = PICT_FRAME;
2752     s->frame_pred_frame_dct = 1;
2753     s->chroma_format = 1;
2754     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2755     avctx->sub_id = 1; /* indicates mpeg1 */
2756     s->out_format = FMT_MPEG1;
2757     s->swap_uv = 0;//AFAIK VCR2 don't have SEQ_HEADER
2758     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2759     
2760     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2761         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n", 
2762                s->avctx->rc_buffer_size, s->bit_rate);
2763     
2764     return 0;
2765 }
2766
2767 static int vcr2_init_sequence(AVCodecContext *avctx)
2768 {
2769     Mpeg1Context *s1 = avctx->priv_data;
2770     MpegEncContext *s = &s1->mpeg_enc_ctx;
2771     int i, v;
2772
2773     /* start new mpeg1 context decoding */
2774     s->out_format = FMT_MPEG1;
2775     if (s1->mpeg_enc_ctx_allocated) {
2776         MPV_common_end(s);
2777     }
2778     s->width  = avctx->coded_width;
2779     s->height = avctx->coded_height;
2780     avctx->has_b_frames= 0; //true?
2781     s->low_delay= 1;
2782
2783     if(avctx->xvmc_acceleration){
2784         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
2785     }else{
2786         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
2787     }
2788
2789     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
2790         if( avctx->idct_algo == FF_IDCT_AUTO )
2791             avctx->idct_algo = FF_IDCT_SIMPLE;
2792     
2793     if (MPV_common_init(s) < 0)
2794         return -1;
2795     exchange_uv(s);//common init reset pblocks, so we swap them here
2796     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB 
2797     s1->mpeg_enc_ctx_allocated = 1;
2798
2799     for(i=0;i<64;i++) {
2800         int j= s->dsp.idct_permutation[i];
2801         v = ff_mpeg1_default_intra_matrix[i];
2802         s->intra_matrix[j] = v;
2803         s->chroma_intra_matrix[j] = v;
2804
2805         v = ff_mpeg1_default_non_intra_matrix[i];
2806         s->inter_matrix[j] = v;
2807         s->chroma_inter_matrix[j] = v;
2808     }
2809
2810     s->progressive_sequence = 1;
2811     s->progressive_frame = 1;
2812     s->picture_structure = PICT_FRAME;
2813     s->frame_pred_frame_dct = 1;
2814     s->chroma_format = 1;
2815     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2816     avctx->sub_id = 2; /* indicates mpeg2 */
2817     return 0;
2818 }
2819
2820
2821 static void mpeg_decode_user_data(AVCodecContext *avctx, 
2822                                   const uint8_t *buf, int buf_size)
2823 {
2824     const uint8_t *p;
2825     int len, flags;
2826     p = buf;
2827     len = buf_size;
2828
2829     /* we parse the DTG active format information */
2830     if (len >= 5 &&
2831         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2832         flags = p[4];
2833         p += 5;
2834         len -= 5;
2835         if (flags & 0x80) {
2836             /* skip event id */
2837             if (len < 2)
2838                 return;
2839             p += 2;
2840             len -= 2;
2841         }
2842         if (flags & 0x40) {
2843             if (len < 1)
2844                 return;
2845             avctx->dtg_active_format = p[0] & 0x0f;
2846         }
2847     }
2848 }
2849
2850 static void mpeg_decode_gop(AVCodecContext *avctx, 
2851                             const uint8_t *buf, int buf_size){
2852     Mpeg1Context *s1 = avctx->priv_data;
2853     MpegEncContext *s = &s1->mpeg_enc_ctx;
2854
2855     int drop_frame_flag;
2856     int time_code_hours, time_code_minutes;
2857     int time_code_seconds, time_code_pictures;
2858     int broken_link;
2859
2860     init_get_bits(&s->gb, buf, buf_size*8);
2861
2862     drop_frame_flag = get_bits1(&s->gb);
2863     
2864     time_code_hours=get_bits(&s->gb,5);
2865     time_code_minutes = get_bits(&s->gb,6);
2866     skip_bits1(&s->gb);//marker bit
2867     time_code_seconds = get_bits(&s->gb,6);
2868     time_code_pictures = get_bits(&s->gb,6);
2869
2870     /*broken_link indicate that after editing the
2871       reference frames of the first B-Frames after GOP I-Frame
2872       are missing (open gop)*/
2873     broken_link = get_bits1(&s->gb);
2874
2875     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2876         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) broken_link=%d\n",
2877             time_code_hours, time_code_minutes, time_code_seconds,
2878             time_code_pictures, broken_link);
2879 }
2880 /**
2881  * finds the end of the current frame in the bitstream.
2882  * @return the position of the first byte of the next frame, or -1
2883  */
2884 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
2885 {
2886     int i;
2887     uint32_t state;
2888     
2889     state= pc->state;
2890     
2891     i=0;
2892     if(!pc->frame_start_found){
2893         for(i=0; i<buf_size; i++){
2894             state= (state<<8) | buf[i];
2895             if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2896                 i++;
2897                 pc->frame_start_found=1;
2898                 break;
2899             }
2900         }
2901     }
2902     
2903     if(pc->frame_start_found){
2904         /* EOF considered as end of frame */
2905         if (buf_size == 0)
2906             return 0;
2907         for(; i<buf_size; i++){
2908             state= (state<<8) | buf[i];
2909             if((state&0xFFFFFF00) == 0x100){
2910                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2911                     pc->frame_start_found=0;
2912                     pc->state=-1; 
2913                     return i-3;
2914                 }
2915             }
2916         }
2917     }        
2918     pc->state= state;
2919     return END_NOT_FOUND;
2920 }
2921
2922 /* handle buffering and image synchronisation */
2923 static int mpeg_decode_frame(AVCodecContext *avctx, 
2924                              void *data, int *data_size,
2925                              uint8_t *buf, int buf_size)
2926 {
2927     Mpeg1Context *s = avctx->priv_data;
2928     const uint8_t *buf_end;
2929     const uint8_t *buf_ptr;
2930     int ret, start_code, input_size;
2931     AVFrame *picture = data;
2932     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2933     dprintf("fill_buffer\n");
2934
2935     if (buf_size == 0) {
2936         /* special case for last picture */
2937         if (s2->low_delay==0 && s2->next_picture_ptr) {
2938             *picture= *(AVFrame*)s2->next_picture_ptr;
2939             s2->next_picture_ptr= NULL;
2940
2941             *data_size = sizeof(AVFrame);
2942         }
2943         return 0;
2944     }
2945
2946     if(s2->flags&CODEC_FLAG_TRUNCATED){
2947         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size);
2948         
2949         if( ff_combine_frame(&s2->parse_context, next, &buf, &buf_size) < 0 )
2950             return buf_size;
2951     }    
2952     
2953     buf_ptr = buf;
2954     buf_end = buf + buf_size;
2955
2956 #if 0    
2957     if (s->repeat_field % 2 == 1) { 
2958         s->repeat_field++;
2959         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2960         //        s2->picture_number, s->repeat_field);
2961         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2962             *data_size = sizeof(AVPicture);
2963             goto the_end;
2964         }
2965     }
2966 #endif
2967
2968     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == ff_get_fourcc("VCR2"))
2969         vcr2_init_sequence(avctx);
2970     
2971     s->slice_count= 0;
2972         
2973     for(;;) {
2974         /* find start next code */
2975         start_code = find_start_code(&buf_ptr, buf_end);
2976         if (start_code < 0){
2977             if(s2->pict_type != B_TYPE || avctx->hurry_up==0){
2978                 if(avctx->thread_count > 1){
2979                     int i;
2980
2981                     avctx->execute(avctx, slice_decode_thread,  (void**)&(s2->thread_context[0]), NULL, s->slice_count);
2982                     for(i=0; i<s->slice_count; i++)
2983                         s2->error_count += s2->thread_context[i]->error_count;
2984                 }
2985                 if (slice_end(avctx, picture)) {
2986                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2987                         *data_size = sizeof(AVPicture);
2988                 }
2989             }
2990             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2991         }
2992         
2993         input_size = buf_end - buf_ptr;
2994
2995         if(avctx->debug & FF_DEBUG_STARTCODE){
2996             av_log(avctx, AV_LOG_DEBUG, "%3X at %zd left %d\n", start_code, buf_ptr-buf, input_size);
2997         }
2998
2999                 /* prepare data for next start code */
3000                 switch(start_code) {
3001                 case SEQ_START_CODE:
3002                     mpeg1_decode_sequence(avctx, buf_ptr, 
3003                                           input_size);
3004                     break;
3005                             
3006                 case PICTURE_START_CODE:
3007                     /* we have a complete image : we try to decompress it */
3008                     mpeg1_decode_picture(avctx, 
3009                                          buf_ptr, input_size);
3010                     break;
3011                 case EXT_START_CODE:
3012                     mpeg_decode_extension(avctx,
3013                                           buf_ptr, input_size);
3014                     break;
3015                 case USER_START_CODE:
3016                     mpeg_decode_user_data(avctx, 
3017                                           buf_ptr, input_size);
3018                     break;
3019                 case GOP_START_CODE:
3020                     s2->first_field=0;
3021                     mpeg_decode_gop(avctx, 
3022                                           buf_ptr, input_size);
3023                     break;
3024                 default:
3025                     if (start_code >= SLICE_MIN_START_CODE &&
3026                         start_code <= SLICE_MAX_START_CODE) {
3027                         int mb_y= start_code - SLICE_MIN_START_CODE;
3028                         
3029                         /* skip b frames if we dont have reference frames */
3030                         if(s2->last_picture_ptr==NULL && s2->pict_type==B_TYPE) break;
3031                         /* skip b frames if we are in a hurry */
3032                         if(avctx->hurry_up && s2->pict_type==B_TYPE) break;
3033                         /* skip everything if we are in a hurry>=5 */
3034                         if(avctx->hurry_up>=5) break;
3035                         
3036                         if (!s->mpeg_enc_ctx_allocated) break;
3037
3038                         if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
3039                             if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
3040                                 break;
3041                         }
3042                         
3043                         if(s2->first_slice){
3044                             s2->first_slice=0;
3045                             if(mpeg_field_start(s2) < 0)
3046                                 return -1;
3047                         }
3048                         
3049                         if(avctx->thread_count > 1){
3050                             int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
3051                             if(threshold <= mb_y){
3052                                 MpegEncContext *thread_context= s2->thread_context[s->slice_count];
3053                                 
3054                                 thread_context->start_mb_y= mb_y;
3055                                 thread_context->end_mb_y  = s2->mb_height;
3056                                 if(s->slice_count){
3057                                     s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
3058                                     ff_update_duplicate_context(thread_context, s2);
3059                                 }
3060                                 init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
3061                                 s->slice_count++;
3062                             }
3063                             buf_ptr += 2; //FIXME add minimum num of bytes per slice
3064                         }else{
3065                             ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
3066                             emms_c();
3067
3068                             if(ret < 0){
3069                                 if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
3070                                     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);
3071                             }else{
3072                                 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);
3073                             }
3074                         }
3075                     }
3076                     break;
3077                 }
3078     }
3079 }
3080
3081 static int mpeg_decode_end(AVCodecContext *avctx)
3082 {
3083     Mpeg1Context *s = avctx->priv_data;
3084
3085     if (s->mpeg_enc_ctx_allocated)
3086         MPV_common_end(&s->mpeg_enc_ctx);
3087     return 0;
3088 }
3089
3090 AVCodec mpeg1video_decoder = {
3091     "mpeg1video",
3092     CODEC_TYPE_VIDEO,
3093     CODEC_ID_MPEG1VIDEO,
3094     sizeof(Mpeg1Context),
3095     mpeg_decode_init,
3096     NULL,
3097     mpeg_decode_end,
3098     mpeg_decode_frame,
3099     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
3100     .flush= ff_mpeg_flush,
3101 };
3102
3103 AVCodec mpeg2video_decoder = {
3104     "mpeg2video",
3105     CODEC_TYPE_VIDEO,
3106     CODEC_ID_MPEG2VIDEO,
3107     sizeof(Mpeg1Context),
3108     mpeg_decode_init,
3109     NULL,
3110     mpeg_decode_end,
3111     mpeg_decode_frame,
3112     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
3113     .flush= ff_mpeg_flush,
3114 };
3115
3116 //legacy decoder
3117 AVCodec mpegvideo_decoder = {
3118     "mpegvideo",
3119     CODEC_TYPE_VIDEO,
3120     CODEC_ID_MPEG2VIDEO,
3121     sizeof(Mpeg1Context),
3122     mpeg_decode_init,
3123     NULL,
3124     mpeg_decode_end,
3125     mpeg_decode_frame,
3126     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
3127     .flush= ff_mpeg_flush,
3128 };
3129
3130 #ifdef CONFIG_ENCODERS
3131
3132 AVCodec mpeg1video_encoder = {
3133     "mpeg1video",
3134     CODEC_TYPE_VIDEO,
3135     CODEC_ID_MPEG1VIDEO,
3136     sizeof(MpegEncContext),
3137     encode_init,
3138     MPV_encode_picture,
3139     MPV_encode_end,
3140     .supported_framerates= frame_rate_tab+1,
3141     .capabilities= CODEC_CAP_DELAY,
3142 };
3143
3144 #ifdef CONFIG_RISKY
3145
3146 AVCodec mpeg2video_encoder = {
3147     "mpeg2video",
3148     CODEC_TYPE_VIDEO,
3149     CODEC_ID_MPEG2VIDEO,
3150     sizeof(MpegEncContext),
3151     encode_init,
3152     MPV_encode_picture,
3153     MPV_encode_end,
3154     .supported_framerates= frame_rate_tab+1,
3155     .capabilities= CODEC_CAP_DELAY,
3156 };
3157 #endif
3158 #endif
3159
3160 #ifdef HAVE_XVMC
3161 static int mpeg_mc_decode_init(AVCodecContext *avctx){
3162     Mpeg1Context *s;
3163
3164     if( avctx->thread_count > 1) 
3165         return -1;
3166     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
3167         return -1;
3168     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
3169         dprintf("mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
3170     }
3171     mpeg_decode_init(avctx);
3172     s = avctx->priv_data;
3173
3174     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
3175     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
3176
3177     return 0;
3178 }
3179
3180 AVCodec mpeg_xvmc_decoder = {
3181     "mpegvideo_xvmc",
3182     CODEC_TYPE_VIDEO,
3183     CODEC_ID_MPEG2VIDEO_XVMC,
3184     sizeof(Mpeg1Context),
3185     mpeg_mc_decode_init,
3186     NULL,
3187     mpeg_decode_end,
3188     mpeg_decode_frame,
3189     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL,
3190     .flush= ff_mpeg_flush,
3191 };
3192
3193 #endif
3194
3195 /* this is ugly i know, but the alternative is too make 
3196    hundreds of vars global and prefix them with ff_mpeg1_
3197    which is far uglier. */
3198 #include "mdec.c"