optimizing non_intra ac coeff decode
[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, int use_static)
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, use_static);
114
115     if(use_static)    
116         rl->rl_vlc[0]= av_mallocz_static(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
117     else
118         rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
119
120     for(i=0; i<rl->vlc.table_size; i++){
121         int code= rl->vlc.table[i][0];
122         int len = rl->vlc.table[i][1];
123         int level, run;
124     
125         if(len==0){ // illegal code
126             run= 65;
127             level= MAX_LEVEL;
128         }else if(len<0){ //more bits needed
129             run= 0;
130             level= code;
131         }else{
132             if(code==rl->n){ //esc
133                 run= 65;
134                 level= 0;
135             }else if(code==rl->n+1){ //eob
136                 run= 0;
137                 level= 127;
138             }else{
139                 run=   rl->table_run  [code] + 1;
140                 level= rl->table_level[code];
141             }
142         }
143         rl->rl_vlc[0][i].len= len;
144         rl->rl_vlc[0][i].level= level;
145         rl->rl_vlc[0][i].run= run;
146     }
147 }
148
149 #ifdef CONFIG_ENCODERS
150 static void init_uni_ac_vlc(RLTable *rl, uint32_t *uni_ac_vlc_bits, uint8_t *uni_ac_vlc_len){
151     int i;
152
153     for(i=0; i<128; i++){
154         int level= i-64;
155         int run;
156         for(run=0; run<64; run++){
157             int len, bits, code;
158             
159             int alevel= ABS(level);
160             int sign= (level>>31)&1;
161
162             if (alevel > rl->max_level[0][run])
163                 code= 111; /*rl->n*/
164             else
165                 code= rl->index_run[0][run] + alevel - 1;
166
167             if (code < 111 /* rl->n */) {
168                 /* store the vlc & sign at once */
169                 len=   mpeg1_vlc[code][1]+1;
170                 bits= (mpeg1_vlc[code][0]<<1) + sign;
171             } else {
172                 len=  mpeg1_vlc[111/*rl->n*/][1]+6;
173                 bits= mpeg1_vlc[111/*rl->n*/][0]<<6;
174
175                 bits|= run;
176                 if (alevel < 128) {
177                     bits<<=8; len+=8;
178                     bits|= level & 0xff;
179                 } else {
180                     bits<<=16; len+=16;
181                     bits|= level & 0xff;
182                     if (level < 0) {
183                         bits|= 0x8001 + level + 255;
184                     } else {
185                         bits|= level & 0xffff;
186                     }
187                 }
188             }
189
190             uni_ac_vlc_bits[UNI_AC_ENC_INDEX(run, i)]= bits;
191             uni_ac_vlc_len [UNI_AC_ENC_INDEX(run, i)]= len;
192         }
193     }
194 }
195
196
197 static int find_frame_rate_index(MpegEncContext *s){
198     int i;
199     int64_t dmin= INT64_MAX;
200     int64_t d;
201
202     for(i=1;i<14;i++) {
203         int64_t n0= 1001LL/frame_rate_tab[i].den*frame_rate_tab[i].num*s->avctx->frame_rate_base;
204         int64_t n1= 1001LL*s->avctx->frame_rate;
205         if(s->avctx->strict_std_compliance >= 0 && i>=9) break;
206
207         d = ABS(n0 - n1);
208         if(d < dmin){
209             dmin=d;
210             s->frame_rate_index= i;
211         }
212     }
213     if(dmin)
214         return -1;
215     else
216         return 0;
217 }
218
219 static int encode_init(AVCodecContext *avctx)
220 {
221     MpegEncContext *s = avctx->priv_data;
222
223     if(MPV_encode_init(avctx) < 0)
224         return -1;
225
226     if(find_frame_rate_index(s) < 0){
227         if(s->strict_std_compliance >=0){
228             av_log(avctx, AV_LOG_ERROR, "MPEG1/2 doesnt support %d/%d fps\n", avctx->frame_rate, avctx->frame_rate_base);
229             return -1;
230         }else{
231             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);
232         }
233     }
234     
235     return 0;
236 }
237
238 static void put_header(MpegEncContext *s, int header)
239 {
240     align_put_bits(&s->pb);
241     put_bits(&s->pb, 16, header>>16);
242     put_bits(&s->pb, 16, header&0xFFFF);
243 }
244
245 /* put sequence header if needed */
246 static void mpeg1_encode_sequence_header(MpegEncContext *s)
247 {
248         unsigned int vbv_buffer_size;
249         unsigned int fps, v;
250         int i;
251         uint64_t time_code;
252         float best_aspect_error= 1E10;
253         float aspect_ratio= av_q2d(s->avctx->sample_aspect_ratio);
254         int constraint_parameter_flag;
255         
256         if(aspect_ratio==0.0) aspect_ratio= 1.0; //pixel aspect 1:1 (VGA)
257         
258         if (s->current_picture.key_frame) {
259             AVRational framerate= frame_rate_tab[s->frame_rate_index];
260
261             /* mpeg1 header repeated every gop */
262             put_header(s, SEQ_START_CODE);
263  
264             put_bits(&s->pb, 12, s->width);
265             put_bits(&s->pb, 12, s->height);
266             
267             for(i=1; i<15; i++){
268                 float error= aspect_ratio;
269                 if(s->codec_id == CODEC_ID_MPEG1VIDEO || i <=1)
270                     error-= 1.0/mpeg1_aspect[i];
271                 else
272                     error-= av_q2d(mpeg2_aspect[i])*s->height/s->width;
273              
274                 error= ABS(error);
275                 
276                 if(error < best_aspect_error){
277                     best_aspect_error= error;
278                     s->aspect_ratio_info= i;
279                 }
280             }
281             
282             put_bits(&s->pb, 4, s->aspect_ratio_info);
283             put_bits(&s->pb, 4, s->frame_rate_index);
284             
285             if(s->avctx->rc_max_rate){
286                 v = (s->avctx->rc_max_rate + 399) / 400;
287                 if (v > 0x3ffff && s->codec_id == CODEC_ID_MPEG1VIDEO)
288                     v = 0x3ffff;
289             }else{
290                 v= 0x3FFFF;
291             }
292
293             if(s->avctx->rc_buffer_size)
294                 vbv_buffer_size = s->avctx->rc_buffer_size;
295             else
296                 /* VBV calculation: Scaled so that a VCD has the proper VBV size of 40 kilobytes */
297                 vbv_buffer_size = (( 20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024;
298             vbv_buffer_size= (vbv_buffer_size + 16383) / 16384;
299
300             put_bits(&s->pb, 18, v & 0x3FFFF);
301             put_bits(&s->pb, 1, 1); /* marker */
302             put_bits(&s->pb, 10, vbv_buffer_size & 0x3FF);
303
304             constraint_parameter_flag= 
305                 s->width <= 768 && s->height <= 576 && 
306                 s->mb_width * s->mb_height <= 396 &&
307                 s->mb_width * s->mb_height * framerate.num <= framerate.den*396*25 &&
308                 framerate.num <= framerate.den*30 &&
309                 s->avctx->me_range && s->avctx->me_range < 128 &&
310                 vbv_buffer_size <= 20 &&
311                 v <= 1856000/400 &&
312                 s->codec_id == CODEC_ID_MPEG1VIDEO;
313                 
314             put_bits(&s->pb, 1, constraint_parameter_flag);
315             
316             ff_write_quant_matrix(&s->pb, s->avctx->intra_matrix);
317             ff_write_quant_matrix(&s->pb, s->avctx->inter_matrix);
318
319             if(s->codec_id == CODEC_ID_MPEG2VIDEO){
320                 put_header(s, EXT_START_CODE);
321                 put_bits(&s->pb, 4, 1); //seq ext
322                 put_bits(&s->pb, 1, 0); //esc
323                 
324                 if(s->avctx->profile == FF_PROFILE_UNKNOWN){
325                     put_bits(&s->pb, 3, 4); //profile
326                 }else{
327                     put_bits(&s->pb, 3, s->avctx->profile); //profile
328                 }
329
330                 if(s->avctx->level == FF_LEVEL_UNKNOWN){
331                     put_bits(&s->pb, 4, 8); //level
332                 }else{
333                     put_bits(&s->pb, 4, s->avctx->level); //level
334                 }
335
336                 put_bits(&s->pb, 1, s->progressive_sequence);
337                 put_bits(&s->pb, 2, 1); //chroma format 4:2:0
338                 put_bits(&s->pb, 2, 0); //horizontal size ext
339                 put_bits(&s->pb, 2, 0); //vertical size ext
340                 put_bits(&s->pb, 12, v>>18); //bitrate ext
341                 put_bits(&s->pb, 1, 1); //marker
342                 put_bits(&s->pb, 8, vbv_buffer_size >>10); //vbv buffer ext
343                 put_bits(&s->pb, 1, s->low_delay);
344                 put_bits(&s->pb, 2, 0); // frame_rate_ext_n
345                 put_bits(&s->pb, 5, 0); // frame_rate_ext_d
346             }
347             
348             put_header(s, GOP_START_CODE);
349             put_bits(&s->pb, 1, 0); /* do drop frame */
350             /* time code : we must convert from the real frame rate to a
351                fake mpeg frame rate in case of low frame rate */
352             fps = (framerate.num + framerate.den/2)/ framerate.den;
353             time_code = s->current_picture_ptr->coded_picture_number;
354
355             s->gop_picture_number = time_code;
356             put_bits(&s->pb, 5, (uint32_t)((time_code / (fps * 3600)) % 24));
357             put_bits(&s->pb, 6, (uint32_t)((time_code / (fps * 60)) % 60));
358             put_bits(&s->pb, 1, 1);
359             put_bits(&s->pb, 6, (uint32_t)((time_code / fps) % 60));
360             put_bits(&s->pb, 6, (uint32_t)((time_code % fps)));
361             put_bits(&s->pb, 1, !!(s->flags & CODEC_FLAG_CLOSED_GOP));
362             put_bits(&s->pb, 1, 0); /* broken link */
363         }
364 }
365
366 static inline void encode_mb_skip_run(MpegEncContext *s, int run){
367     while (run >= 33) {
368         put_bits(&s->pb, 11, 0x008);
369         run -= 33;
370     }
371     put_bits(&s->pb, mbAddrIncrTable[run][1], 
372              mbAddrIncrTable[run][0]);
373 }
374 #endif //CONFIG_ENCODERS
375
376 static void common_init(MpegEncContext *s)
377 {
378
379     s->y_dc_scale_table=
380     s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
381
382 }
383
384 void ff_mpeg1_clean_buffers(MpegEncContext *s){
385     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
386     s->last_dc[1] = s->last_dc[0];
387     s->last_dc[2] = s->last_dc[0];
388     memset(s->last_mv, 0, sizeof(s->last_mv));
389 }
390
391 #ifdef CONFIG_ENCODERS
392
393 void ff_mpeg1_encode_slice_header(MpegEncContext *s){
394     put_header(s, SLICE_MIN_START_CODE + s->mb_y);
395     put_bits(&s->pb, 5, s->qscale); /* quantizer scale */
396     put_bits(&s->pb, 1, 0); /* slice extra information */
397 }
398
399 void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
400 {
401     mpeg1_encode_sequence_header(s);
402
403     /* mpeg1 picture header */
404     put_header(s, PICTURE_START_CODE);
405     /* temporal reference */
406
407     // RAL: s->picture_number instead of s->fake_picture_number
408     put_bits(&s->pb, 10, (s->picture_number - 
409                           s->gop_picture_number) & 0x3ff); 
410     put_bits(&s->pb, 3, s->pict_type);
411
412     s->vbv_delay_ptr= s->pb.buf + put_bits_count(&s->pb)/8;
413     put_bits(&s->pb, 16, 0xFFFF); /* vbv_delay */
414     
415     // RAL: Forward f_code also needed for B frames
416     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
417         put_bits(&s->pb, 1, 0); /* half pel coordinates */
418         if(s->codec_id == CODEC_ID_MPEG1VIDEO)
419             put_bits(&s->pb, 3, s->f_code); /* forward_f_code */
420         else
421             put_bits(&s->pb, 3, 7); /* forward_f_code */
422     }
423     
424     // RAL: Backward f_code necessary for B frames
425     if (s->pict_type == B_TYPE) {
426         put_bits(&s->pb, 1, 0); /* half pel coordinates */
427         if(s->codec_id == CODEC_ID_MPEG1VIDEO)
428             put_bits(&s->pb, 3, s->b_code); /* backward_f_code */
429         else
430             put_bits(&s->pb, 3, 7); /* backward_f_code */
431     }
432
433     put_bits(&s->pb, 1, 0); /* extra bit picture */
434
435     s->frame_pred_frame_dct = 1;
436     if(s->codec_id == CODEC_ID_MPEG2VIDEO){
437         put_header(s, EXT_START_CODE);
438         put_bits(&s->pb, 4, 8); //pic ext
439         if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
440             put_bits(&s->pb, 4, s->f_code);
441             put_bits(&s->pb, 4, s->f_code);
442         }else{
443             put_bits(&s->pb, 8, 255);
444         }
445         if (s->pict_type == B_TYPE) {
446             put_bits(&s->pb, 4, s->b_code);
447             put_bits(&s->pb, 4, s->b_code);
448         }else{
449             put_bits(&s->pb, 8, 255);
450         }
451         put_bits(&s->pb, 2, s->intra_dc_precision);
452         
453         assert(s->picture_structure == PICT_FRAME);
454         put_bits(&s->pb, 2, s->picture_structure);
455         if (s->progressive_sequence) {
456             put_bits(&s->pb, 1, 0); /* no repeat */
457         } else {
458             put_bits(&s->pb, 1, s->current_picture_ptr->top_field_first);
459         }
460         /* XXX: optimize the generation of this flag with entropy
461            measures */
462         s->frame_pred_frame_dct = s->progressive_sequence;
463         
464         put_bits(&s->pb, 1, s->frame_pred_frame_dct);
465         put_bits(&s->pb, 1, s->concealment_motion_vectors);
466         put_bits(&s->pb, 1, s->q_scale_type);
467         put_bits(&s->pb, 1, s->intra_vlc_format);
468         put_bits(&s->pb, 1, s->alternate_scan);
469         put_bits(&s->pb, 1, s->repeat_first_field);
470         put_bits(&s->pb, 1, s->chroma_420_type=1);
471         s->progressive_frame = s->progressive_sequence;
472         put_bits(&s->pb, 1, s->progressive_frame);
473         put_bits(&s->pb, 1, 0); //composite_display_flag
474     }
475     if(s->flags & CODEC_FLAG_SVCD_SCAN_OFFSET){
476         int i;
477
478         put_header(s, USER_START_CODE);
479         for(i=0; i<sizeof(svcd_scan_offset_placeholder); i++){
480             put_bits(&s->pb, 8, svcd_scan_offset_placeholder[i]);
481         }
482     }
483     
484     s->mb_y=0;
485     ff_mpeg1_encode_slice_header(s);
486 }
487
488 static inline void put_mb_modes(MpegEncContext *s, int n, int bits, 
489                                 int has_mv, int field_motion)
490 {
491     put_bits(&s->pb, n, bits);
492     if (!s->frame_pred_frame_dct) {
493         if (has_mv) 
494             put_bits(&s->pb, 2, 2 - field_motion); /* motion_type: frame/field */
495         put_bits(&s->pb, 1, s->interlaced_dct);
496     }
497 }
498
499 void mpeg1_encode_mb(MpegEncContext *s,
500                      DCTELEM block[6][64],
501                      int motion_x, int motion_y)
502 {
503     int i, cbp;
504     const int mb_x = s->mb_x;
505     const int mb_y = s->mb_y;
506     const int first_mb= mb_x == s->resync_mb_x && mb_y == s->resync_mb_y;
507
508     /* compute cbp */
509     cbp = 0;
510     for(i=0;i<6;i++) {
511         if (s->block_last_index[i] >= 0)
512             cbp |= 1 << (5 - i);
513     }
514     
515     if (cbp == 0 && !first_mb && s->mv_type == MV_TYPE_16X16 &&
516         (mb_x != s->mb_width - 1 || (mb_y != s->mb_height - 1 && s->codec_id == CODEC_ID_MPEG1VIDEO)) && 
517         ((s->pict_type == P_TYPE && (motion_x | motion_y) == 0) ||
518         (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) |
519         ((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))) {
520         s->mb_skip_run++;
521         s->qscale -= s->dquant;
522         s->skip_count++;
523         s->misc_bits++;
524         s->last_bits++;
525         if(s->pict_type == P_TYPE){
526             s->last_mv[0][1][0]= s->last_mv[0][0][0]= 
527             s->last_mv[0][1][1]= s->last_mv[0][0][1]= 0;
528         }
529     } else {
530         if(first_mb){
531             assert(s->mb_skip_run == 0);
532             encode_mb_skip_run(s, s->mb_x);
533         }else{
534             encode_mb_skip_run(s, s->mb_skip_run);
535         }
536         
537         if (s->pict_type == I_TYPE) {
538             if(s->dquant && cbp){
539                 put_mb_modes(s, 2, 1, 0, 0); /* macroblock_type : macroblock_quant = 1 */
540                 put_bits(&s->pb, 5, s->qscale);
541             }else{
542                 put_mb_modes(s, 1, 1, 0, 0); /* macroblock_type : macroblock_quant = 0 */
543                 s->qscale -= s->dquant;
544             }
545             s->misc_bits+= get_bits_diff(s);
546             s->i_count++;
547         } else if (s->mb_intra) {
548             if(s->dquant && cbp){
549                 put_mb_modes(s, 6, 0x01, 0, 0);
550                 put_bits(&s->pb, 5, s->qscale);
551             }else{
552                 put_mb_modes(s, 5, 0x03, 0, 0);
553                 s->qscale -= s->dquant;
554             }
555             s->misc_bits+= get_bits_diff(s);
556             s->i_count++;
557             memset(s->last_mv, 0, sizeof(s->last_mv));
558         } else if (s->pict_type == P_TYPE) { 
559             if(s->mv_type == MV_TYPE_16X16){
560                 if (cbp != 0) {
561                     if ((motion_x|motion_y) == 0) {
562                         if(s->dquant){
563                             put_mb_modes(s, 5, 1, 0, 0); /* macroblock_pattern & quant */
564                             put_bits(&s->pb, 5, s->qscale);
565                         }else{
566                             put_mb_modes(s, 2, 1, 0, 0); /* macroblock_pattern only */
567                         }
568                         s->misc_bits+= get_bits_diff(s);
569                     } else {
570                         if(s->dquant){
571                             put_mb_modes(s, 5, 2, 1, 0); /* motion + cbp */
572                             put_bits(&s->pb, 5, s->qscale);
573                         }else{
574                             put_mb_modes(s, 1, 1, 1, 0); /* motion + cbp */
575                         }
576                         s->misc_bits+= get_bits_diff(s);
577                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
578                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
579                         s->mv_bits+= get_bits_diff(s);
580                     }
581                 } else {
582                     put_bits(&s->pb, 3, 1); /* motion only */
583                     if (!s->frame_pred_frame_dct)
584                         put_bits(&s->pb, 2, 2); /* motion_type: frame */
585                     s->misc_bits+= get_bits_diff(s);
586                     mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
587                     mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
588                     s->qscale -= s->dquant;
589                     s->mv_bits+= get_bits_diff(s);
590                 }
591                 s->last_mv[0][1][0]= s->last_mv[0][0][0]= motion_x;
592                 s->last_mv[0][1][1]= s->last_mv[0][0][1]= motion_y;
593             }else{
594                 assert(!s->frame_pred_frame_dct && s->mv_type == MV_TYPE_FIELD);
595
596                 if (cbp) {
597                     if(s->dquant){
598                         put_mb_modes(s, 5, 2, 1, 1); /* motion + cbp */
599                         put_bits(&s->pb, 5, s->qscale);
600                     }else{
601                         put_mb_modes(s, 1, 1, 1, 1); /* motion + cbp */
602                     }
603                 } else {
604                     put_bits(&s->pb, 3, 1); /* motion only */
605                     put_bits(&s->pb, 2, 1); /* motion_type: field */
606                     s->qscale -= s->dquant;
607                 }
608                 s->misc_bits+= get_bits_diff(s);
609                 for(i=0; i<2; i++){
610                     put_bits(&s->pb, 1, s->field_select[0][i]);
611                     mpeg1_encode_motion(s, s->mv[0][i][0] -  s->last_mv[0][i][0]    , s->f_code);
612                     mpeg1_encode_motion(s, s->mv[0][i][1] - (s->last_mv[0][i][1]>>1), s->f_code);
613                     s->last_mv[0][i][0]=   s->mv[0][i][0];
614                     s->last_mv[0][i][1]= 2*s->mv[0][i][1];
615                 }
616                 s->mv_bits+= get_bits_diff(s);
617             }
618             if(cbp)
619                 put_bits(&s->pb, mbPatTable[cbp][1], mbPatTable[cbp][0]);
620             s->f_count++;
621         } else{  
622             static const int mb_type_len[4]={0,3,4,2}; //bak,for,bi
623
624             if(s->mv_type == MV_TYPE_16X16){
625                 if (cbp){    // With coded bloc pattern
626                     if (s->dquant) {
627                         if(s->mv_dir == MV_DIR_FORWARD)
628                             put_mb_modes(s, 6, 3, 1, 0);
629                         else
630                             put_mb_modes(s, mb_type_len[s->mv_dir]+3, 2, 1, 0);
631                         put_bits(&s->pb, 5, s->qscale);
632                     } else {
633                         put_mb_modes(s, mb_type_len[s->mv_dir], 3, 1, 0);
634                     }
635                 }else{    // No coded bloc pattern
636                     put_bits(&s->pb, mb_type_len[s->mv_dir], 2);
637                     if (!s->frame_pred_frame_dct)
638                         put_bits(&s->pb, 2, 2); /* motion_type: frame */
639                     s->qscale -= s->dquant;
640                 }
641                 s->misc_bits += get_bits_diff(s);
642                 if (s->mv_dir&MV_DIR_FORWARD){
643                     mpeg1_encode_motion(s, s->mv[0][0][0] - s->last_mv[0][0][0], s->f_code); 
644                     mpeg1_encode_motion(s, s->mv[0][0][1] - s->last_mv[0][0][1], s->f_code); 
645                     s->last_mv[0][0][0]=s->last_mv[0][1][0]= s->mv[0][0][0];
646                     s->last_mv[0][0][1]=s->last_mv[0][1][1]= s->mv[0][0][1];
647                     s->f_count++;
648                 }
649                 if (s->mv_dir&MV_DIR_BACKWARD){
650                     mpeg1_encode_motion(s, s->mv[1][0][0] - s->last_mv[1][0][0], s->b_code); 
651                     mpeg1_encode_motion(s, s->mv[1][0][1] - s->last_mv[1][0][1], s->b_code); 
652                     s->last_mv[1][0][0]=s->last_mv[1][1][0]= s->mv[1][0][0];
653                     s->last_mv[1][0][1]=s->last_mv[1][1][1]= s->mv[1][0][1];
654                     s->b_count++;
655                 }
656             }else{
657                 assert(s->mv_type == MV_TYPE_FIELD);
658                 assert(!s->frame_pred_frame_dct);
659                 if (cbp){    // With coded bloc pattern
660                     if (s->dquant) {
661                         if(s->mv_dir == MV_DIR_FORWARD)
662                             put_mb_modes(s, 6, 3, 1, 1);
663                         else
664                             put_mb_modes(s, mb_type_len[s->mv_dir]+3, 2, 1, 1);
665                         put_bits(&s->pb, 5, s->qscale);
666                     } else {
667                         put_mb_modes(s, mb_type_len[s->mv_dir], 3, 1, 1);
668                     }
669                 }else{    // No coded bloc pattern
670                     put_bits(&s->pb, mb_type_len[s->mv_dir], 2);
671                     put_bits(&s->pb, 2, 1); /* motion_type: field */
672                     s->qscale -= s->dquant;
673                 }
674                 s->misc_bits += get_bits_diff(s);
675                 if (s->mv_dir&MV_DIR_FORWARD){
676                     for(i=0; i<2; i++){
677                         put_bits(&s->pb, 1, s->field_select[0][i]);
678                         mpeg1_encode_motion(s, s->mv[0][i][0] -  s->last_mv[0][i][0]    , s->f_code);
679                         mpeg1_encode_motion(s, s->mv[0][i][1] - (s->last_mv[0][i][1]>>1), s->f_code);
680                         s->last_mv[0][i][0]=   s->mv[0][i][0];
681                         s->last_mv[0][i][1]= 2*s->mv[0][i][1];
682                     }
683                     s->f_count++;
684                 }
685                 if (s->mv_dir&MV_DIR_BACKWARD){
686                     for(i=0; i<2; i++){
687                         put_bits(&s->pb, 1, s->field_select[1][i]);
688                         mpeg1_encode_motion(s, s->mv[1][i][0] -  s->last_mv[1][i][0]    , s->b_code);
689                         mpeg1_encode_motion(s, s->mv[1][i][1] - (s->last_mv[1][i][1]>>1), s->b_code);
690                         s->last_mv[1][i][0]=   s->mv[1][i][0];
691                         s->last_mv[1][i][1]= 2*s->mv[1][i][1];
692                     }
693                     s->b_count++;
694                 }
695             }
696             s->mv_bits += get_bits_diff(s);
697             if(cbp)
698                 put_bits(&s->pb, mbPatTable[cbp][1], mbPatTable[cbp][0]);
699         }
700         for(i=0;i<6;i++) {
701             if (cbp & (1 << (5 - i))) {
702                 mpeg1_encode_block(s, block[i], i);
703             }
704         }
705         s->mb_skip_run = 0;
706         if(s->mb_intra)
707             s->i_tex_bits+= get_bits_diff(s);
708         else
709             s->p_tex_bits+= get_bits_diff(s);
710     }
711 }
712
713 // RAL: Parameter added: f_or_b_code
714 static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code)
715 {
716     int code, bit_size, l, bits, range, sign;
717
718     if (val == 0) {
719         /* zero vector */
720         code = 0;
721         put_bits(&s->pb,
722                  mbMotionVectorTable[0][1], 
723                  mbMotionVectorTable[0][0]); 
724     } else {
725         bit_size = f_or_b_code - 1;
726         range = 1 << bit_size;
727         /* modulo encoding */
728         l= INT_BIT - 5 - bit_size;
729         val= (val<<l)>>l;
730
731         if (val >= 0) {
732             val--;
733             code = (val >> bit_size) + 1;
734             bits = val & (range - 1);
735             sign = 0;
736         } else {
737             val = -val;
738             val--;
739             code = (val >> bit_size) + 1;
740             bits = val & (range - 1);
741             sign = 1;
742         }
743
744         assert(code > 0 && code <= 16);
745
746         put_bits(&s->pb,
747                  mbMotionVectorTable[code][1], 
748                  mbMotionVectorTable[code][0]); 
749
750         put_bits(&s->pb, 1, sign);
751         if (bit_size > 0) {
752             put_bits(&s->pb, bit_size, bits);
753         }
754     }
755 }
756
757 void ff_mpeg1_encode_init(MpegEncContext *s)
758 {
759     static int done=0;
760
761     common_init(s);
762
763     if(!done){
764         int f_code;
765         int mv;
766         int i;
767
768         done=1;
769         init_rl(&rl_mpeg1, 1);
770
771         for(i=0; i<64; i++)
772         {
773                 mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i];
774                 mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i];
775         }
776         
777         init_uni_ac_vlc(&rl_mpeg1, uni_mpeg1_ac_vlc_bits, uni_mpeg1_ac_vlc_len);
778
779         /* build unified dc encoding tables */
780         for(i=-255; i<256; i++)
781         {
782                 int adiff, index;
783                 int bits, code;
784                 int diff=i;
785
786                 adiff = ABS(diff);
787                 if(diff<0) diff--;
788                 index = av_log2(2*adiff);
789
790                 bits= vlc_dc_lum_bits[index] + index;
791                 code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1));
792                 mpeg1_lum_dc_uni[i+255]= bits + (code<<8);
793                 
794                 bits= vlc_dc_chroma_bits[index] + index;
795                 code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1));
796                 mpeg1_chr_dc_uni[i+255]= bits + (code<<8);
797         }
798
799         mv_penalty= av_mallocz( sizeof(uint8_t)*(MAX_FCODE+1)*(2*MAX_MV+1) );
800
801         for(f_code=1; f_code<=MAX_FCODE; f_code++){
802             for(mv=-MAX_MV; mv<=MAX_MV; mv++){
803                 int len;
804
805                 if(mv==0) len= mbMotionVectorTable[0][1];
806                 else{
807                     int val, bit_size, range, code;
808
809                     bit_size = f_code - 1;
810                     range = 1 << bit_size;
811
812                     val=mv;
813                     if (val < 0) 
814                         val = -val;
815                     val--;
816                     code = (val >> bit_size) + 1;
817                     if(code<17){
818                         len= mbMotionVectorTable[code][1] + 1 + bit_size;
819                     }else{
820                         len= mbMotionVectorTable[16][1] + 2 + bit_size;
821                     }
822                 }
823
824                 mv_penalty[f_code][mv+MAX_MV]= len;
825             }
826         }
827         
828
829         for(f_code=MAX_FCODE; f_code>0; f_code--){
830             for(mv=-(8<<f_code); mv<(8<<f_code); mv++){
831                 fcode_tab[mv+MAX_MV]= f_code;
832             }
833         }
834     }
835     s->me.mv_penalty= mv_penalty;
836     s->fcode_tab= fcode_tab;
837     if(s->codec_id == CODEC_ID_MPEG1VIDEO){
838         s->min_qcoeff=-255;
839         s->max_qcoeff= 255;
840     }else{
841         s->min_qcoeff=-2047;
842         s->max_qcoeff= 2047;
843     }
844     s->intra_ac_vlc_length=
845     s->inter_ac_vlc_length=
846     s->intra_ac_vlc_last_length=
847     s->inter_ac_vlc_last_length= uni_mpeg1_ac_vlc_len;
848 }
849
850 static inline void encode_dc(MpegEncContext *s, int diff, int component)
851 {
852   if(((unsigned) (diff+255)) >= 511){
853         int index;
854
855         if(diff<0){
856             index= av_log2_16bit(-2*diff);
857             diff--;
858         }else{
859             index= av_log2_16bit(2*diff);
860         }
861         if (component == 0) {
862             put_bits(
863                 &s->pb, 
864                 vlc_dc_lum_bits[index] + index,
865                 (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1)));
866         }else{
867             put_bits(
868                 &s->pb, 
869                 vlc_dc_chroma_bits[index] + index,
870                 (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1)));
871         }
872   }else{
873     if (component == 0) {
874         put_bits(
875             &s->pb, 
876             mpeg1_lum_dc_uni[diff+255]&0xFF,
877             mpeg1_lum_dc_uni[diff+255]>>8);
878     } else {
879         put_bits(
880             &s->pb, 
881             mpeg1_chr_dc_uni[diff+255]&0xFF,
882             mpeg1_chr_dc_uni[diff+255]>>8);
883     }
884   }
885 }
886
887 static void mpeg1_encode_block(MpegEncContext *s, 
888                                DCTELEM *block, 
889                                int n)
890 {
891     int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign;
892     int code, component;
893 //    RLTable *rl = &rl_mpeg1;
894
895     last_index = s->block_last_index[n];
896
897     /* DC coef */
898     if (s->mb_intra) {
899         component = (n <= 3 ? 0 : n - 4 + 1);
900         dc = block[0]; /* overflow is impossible */
901         diff = dc - s->last_dc[component];
902         encode_dc(s, diff, component);
903         s->last_dc[component] = dc;
904         i = 1;
905 /*
906         if (s->intra_vlc_format)
907             rl = &rl_mpeg2;
908         else
909             rl = &rl_mpeg1;
910 */
911     } else {
912         /* encode the first coefficient : needs to be done here because
913            it is handled slightly differently */
914         level = block[0];
915         if (abs(level) == 1) {
916                 code = ((uint32_t)level >> 31); /* the sign bit */
917                 put_bits(&s->pb, 2, code | 0x02);
918                 i = 1;
919         } else {
920             i = 0;
921             last_non_zero = -1;
922             goto next_coef;
923         }
924     }
925
926     /* now quantify & encode AC coefs */
927     last_non_zero = i - 1;
928
929     for(;i<=last_index;i++) {
930         j = s->intra_scantable.permutated[i];
931         level = block[j];
932     next_coef:
933 #if 0
934         if (level != 0)
935             dprintf("level[%d]=%d\n", i, level);
936 #endif            
937         /* encode using VLC */
938         if (level != 0) {
939             run = i - last_non_zero - 1;
940             
941             alevel= level;
942             MASK_ABS(sign, alevel)
943             sign&=1;
944
945 //            code = get_rl_index(rl, 0, run, alevel);
946             if (alevel <= mpeg1_max_level[0][run]){
947                 code= mpeg1_index_run[0][run] + alevel - 1;
948                 /* store the vlc & sign at once */
949                 put_bits(&s->pb, mpeg1_vlc[code][1]+1, (mpeg1_vlc[code][0]<<1) + sign);
950             } else {
951                 /* escape seems to be pretty rare <5% so i dont optimize it */
952                 put_bits(&s->pb, mpeg1_vlc[111/*rl->n*/][1], mpeg1_vlc[111/*rl->n*/][0]);
953                 /* escape: only clip in this case */
954                 put_bits(&s->pb, 6, run);
955                 if(s->codec_id == CODEC_ID_MPEG1VIDEO){
956                     if (alevel < 128) {
957                         put_bits(&s->pb, 8, level & 0xff);
958                     } else {
959                         if (level < 0) {
960                             put_bits(&s->pb, 16, 0x8001 + level + 255);
961                         } else {
962                             put_bits(&s->pb, 16, level & 0xffff);
963                         }
964                     }
965                 }else{
966                     put_bits(&s->pb, 12, level & 0xfff);
967                 }
968             }
969             last_non_zero = i;
970         }
971     }
972     /* end of block */
973     put_bits(&s->pb, 2, 0x2);
974 }
975 #endif //CONFIG_ENCODERS
976
977 /******************************************/
978 /* decoding */
979
980 static VLC dc_lum_vlc;
981 static VLC dc_chroma_vlc;
982 static VLC mv_vlc;
983 static VLC mbincr_vlc;
984 static VLC mb_ptype_vlc;
985 static VLC mb_btype_vlc;
986 static VLC mb_pat_vlc;
987
988 static void init_vlcs(void)
989 {
990     static int done = 0;
991
992     if (!done) {
993         done = 1;
994
995         init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12, 
996                  vlc_dc_lum_bits, 1, 1,
997                  vlc_dc_lum_code, 2, 2, 1);
998         init_vlc(&dc_chroma_vlc,  DC_VLC_BITS, 12, 
999                  vlc_dc_chroma_bits, 1, 1,
1000                  vlc_dc_chroma_code, 2, 2, 1);
1001         init_vlc(&mv_vlc, MV_VLC_BITS, 17, 
1002                  &mbMotionVectorTable[0][1], 2, 1,
1003                  &mbMotionVectorTable[0][0], 2, 1, 1);
1004         init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36, 
1005                  &mbAddrIncrTable[0][1], 2, 1,
1006                  &mbAddrIncrTable[0][0], 2, 1, 1);
1007         init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
1008                  &mbPatTable[0][1], 2, 1,
1009                  &mbPatTable[0][0], 2, 1, 1);
1010         
1011         init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7, 
1012                  &table_mb_ptype[0][1], 2, 1,
1013                  &table_mb_ptype[0][0], 2, 1, 1);
1014         init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11, 
1015                  &table_mb_btype[0][1], 2, 1,
1016                  &table_mb_btype[0][0], 2, 1, 1);
1017         init_rl(&rl_mpeg1, 1);
1018         init_rl(&rl_mpeg2, 1);
1019
1020         init_2d_vlc_rl(&rl_mpeg1, 1);
1021         init_2d_vlc_rl(&rl_mpeg2, 1);
1022     }
1023 }
1024
1025 static inline int get_dmv(MpegEncContext *s)
1026 {
1027     if(get_bits1(&s->gb)) 
1028         return 1 - (get_bits1(&s->gb) << 1);
1029     else
1030         return 0;
1031 }
1032
1033 static inline int get_qscale(MpegEncContext *s)
1034 {
1035     int qscale = get_bits(&s->gb, 5);
1036     if (s->q_scale_type) {
1037         return non_linear_qscale[qscale];
1038     } else {
1039         return qscale << 1;
1040     }
1041 }
1042
1043 /* motion type (for mpeg2) */
1044 #define MT_FIELD 1
1045 #define MT_FRAME 2
1046 #define MT_16X8  2
1047 #define MT_DMV   3
1048
1049 static int mpeg_decode_mb(MpegEncContext *s,
1050                           DCTELEM block[12][64])
1051 {
1052     int i, j, k, cbp, val, mb_type, motion_type;
1053     const int mb_block_count = 4 + (1<< s->chroma_format);
1054
1055     dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
1056
1057     assert(s->mb_skiped==0);
1058
1059     if (s->mb_skip_run-- != 0) {
1060         if(s->pict_type == I_TYPE){
1061             av_log(s->avctx, AV_LOG_ERROR, "skiped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1062             return -1;
1063         }
1064     
1065         /* skip mb */
1066         s->mb_intra = 0;
1067         for(i=0;i<12;i++)
1068             s->block_last_index[i] = -1;
1069         if(s->picture_structure == PICT_FRAME)
1070             s->mv_type = MV_TYPE_16X16;
1071         else
1072             s->mv_type = MV_TYPE_FIELD;
1073         if (s->pict_type == P_TYPE) {
1074             /* if P type, zero motion vector is implied */
1075             s->mv_dir = MV_DIR_FORWARD;
1076             s->mv[0][0][0] = s->mv[0][0][1] = 0;
1077             s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1078             s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1079             s->field_select[0][0]= s->picture_structure - 1;
1080             s->mb_skiped = 1;
1081             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
1082         } else {
1083             int mb_type;
1084             
1085             if(s->mb_x)
1086                 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
1087             else
1088                 mb_type= s->current_picture.mb_type[ s->mb_width + (s->mb_y-1)*s->mb_stride - 1]; // FIXME not sure if this is allowed in mpeg at all, 
1089             if(IS_INTRA(mb_type))
1090                 return -1;
1091             
1092             /* if B type, reuse previous vectors and directions */
1093             s->mv[0][0][0] = s->last_mv[0][0][0];
1094             s->mv[0][0][1] = s->last_mv[0][0][1];
1095             s->mv[1][0][0] = s->last_mv[1][0][0];
1096             s->mv[1][0][1] = s->last_mv[1][0][1];
1097
1098             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= 
1099                 mb_type | MB_TYPE_SKIP;
1100 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
1101
1102             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0) 
1103                 s->mb_skiped = 1;
1104         }
1105
1106         return 0;
1107     }
1108
1109     switch(s->pict_type) {
1110     default:
1111     case I_TYPE:
1112         if (get_bits1(&s->gb) == 0) {
1113             if (get_bits1(&s->gb) == 0){
1114                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
1115                 return -1;
1116             }
1117             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
1118         } else {
1119             mb_type = MB_TYPE_INTRA;
1120         }
1121         break;
1122     case P_TYPE:
1123         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
1124         if (mb_type < 0){
1125             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
1126             return -1;
1127         }
1128         mb_type = ptype2mb_type[ mb_type ];
1129         break;
1130     case B_TYPE:
1131         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
1132         if (mb_type < 0){
1133             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
1134             return -1;
1135         }
1136         mb_type = btype2mb_type[ mb_type ];
1137         break;
1138     }
1139     dprintf("mb_type=%x\n", mb_type);
1140 //    motion_type = 0; /* avoid warning */
1141     if (IS_INTRA(mb_type)) {
1142         /* compute dct type */
1143         if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1144             !s->frame_pred_frame_dct) {
1145             s->interlaced_dct = get_bits1(&s->gb);
1146         }
1147
1148         if (IS_QUANT(mb_type))
1149             s->qscale = get_qscale(s);
1150         
1151         if (s->concealment_motion_vectors) {
1152             /* just parse them */
1153             if (s->picture_structure != PICT_FRAME) 
1154                 skip_bits1(&s->gb); /* field select */
1155             
1156             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] = 
1157                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
1158             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] = 
1159                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
1160
1161             skip_bits1(&s->gb); /* marker */
1162         }else
1163             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
1164         s->mb_intra = 1;
1165 #ifdef HAVE_XVMC
1166         //one 1 we memcpy blocks in xvmcvideo
1167         if(s->avctx->xvmc_acceleration > 1){
1168             XVMC_pack_pblocks(s,-1);//inter are always full blocks
1169             if(s->swap_uv){
1170                 exchange_uv(s);
1171             }
1172         }
1173 #endif
1174
1175         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
1176             for(i=0;i<mb_block_count;i++) {
1177                 if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
1178                     return -1;
1179             }
1180         } else {
1181             for(i=0;i<6;i++) {
1182                 if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
1183                     return -1;
1184             }
1185         }
1186     } else {
1187         if (mb_type & MB_TYPE_ZERO_MV){
1188             assert(mb_type & MB_TYPE_CBP);
1189
1190             /* compute dct type */
1191             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1192                 !s->frame_pred_frame_dct) {
1193                 s->interlaced_dct = get_bits1(&s->gb);
1194             }
1195
1196             if (IS_QUANT(mb_type))
1197                 s->qscale = get_qscale(s);
1198
1199             s->mv_dir = MV_DIR_FORWARD;
1200             if(s->picture_structure == PICT_FRAME)
1201                 s->mv_type = MV_TYPE_16X16;
1202             else{
1203                 s->mv_type = MV_TYPE_FIELD;
1204                 mb_type |= MB_TYPE_INTERLACED;
1205                 s->field_select[0][0]= s->picture_structure - 1;
1206             }
1207             s->last_mv[0][0][0] = 0;
1208             s->last_mv[0][0][1] = 0;
1209             s->last_mv[0][1][0] = 0;
1210             s->last_mv[0][1][1] = 0;
1211             s->mv[0][0][0] = 0;
1212             s->mv[0][0][1] = 0;
1213         }else{
1214             assert(mb_type & MB_TYPE_L0L1);
1215 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
1216             /* get additionnal motion vector type */
1217             if (s->frame_pred_frame_dct) 
1218                 motion_type = MT_FRAME;
1219             else{
1220                 motion_type = get_bits(&s->gb, 2);
1221             }
1222
1223             /* compute dct type */
1224             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1225                 !s->frame_pred_frame_dct && HAS_CBP(mb_type)) {
1226                 s->interlaced_dct = get_bits1(&s->gb);
1227             }
1228
1229             if (IS_QUANT(mb_type))
1230                 s->qscale = get_qscale(s);
1231
1232             /* motion vectors */
1233             s->mv_dir = 0;
1234             for(i=0;i<2;i++) {
1235                 if (USES_LIST(mb_type, i)) {
1236                     s->mv_dir |= (MV_DIR_FORWARD >> i);
1237                     dprintf("motion_type=%d\n", motion_type);
1238                     switch(motion_type) {
1239                     case MT_FRAME: /* or MT_16X8 */
1240                         if (s->picture_structure == PICT_FRAME) {
1241                             /* MT_FRAME */
1242                             mb_type |= MB_TYPE_16x16; 
1243                             s->mv_type = MV_TYPE_16X16;
1244                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] = 
1245                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
1246                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] = 
1247                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
1248                             /* full_pel: only for mpeg1 */
1249                             if (s->full_pel[i]){
1250                                 s->mv[i][0][0] <<= 1;
1251                                 s->mv[i][0][1] <<= 1;
1252                             }
1253                         } else {
1254                             /* MT_16X8 */
1255                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED; 
1256                             s->mv_type = MV_TYPE_16X8;
1257                             for(j=0;j<2;j++) {
1258                                 s->field_select[i][j] = get_bits1(&s->gb);
1259                                 for(k=0;k<2;k++) {
1260                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1261                                                              s->last_mv[i][j][k]);
1262                                     s->last_mv[i][j][k] = val;
1263                                     s->mv[i][j][k] = val;
1264                                 }
1265                             }
1266                         }
1267                         break;
1268                     case MT_FIELD:
1269                         s->mv_type = MV_TYPE_FIELD;
1270                         if (s->picture_structure == PICT_FRAME) {
1271                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED; 
1272                             for(j=0;j<2;j++) {
1273                                 s->field_select[i][j] = get_bits1(&s->gb);
1274                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1275                                                          s->last_mv[i][j][0]);
1276                                 s->last_mv[i][j][0] = val;
1277                                 s->mv[i][j][0] = val;
1278                                 dprintf("fmx=%d\n", val);
1279                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1280                                                          s->last_mv[i][j][1] >> 1);
1281                                 s->last_mv[i][j][1] = val << 1;
1282                                 s->mv[i][j][1] = val;
1283                                 dprintf("fmy=%d\n", val);
1284                             }
1285                         } else {
1286                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED; 
1287                             s->field_select[i][0] = get_bits1(&s->gb);
1288                             for(k=0;k<2;k++) {
1289                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1290                                                          s->last_mv[i][0][k]);
1291                                 s->last_mv[i][0][k] = val;
1292                                 s->last_mv[i][1][k] = val;
1293                                 s->mv[i][0][k] = val;
1294                             }
1295                         }
1296                         break;
1297                     case MT_DMV:
1298                         {
1299                             int dmx, dmy, mx, my, m;
1300
1301                             mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0], 
1302                                                     s->last_mv[i][0][0]);
1303                             s->last_mv[i][0][0] = mx;
1304                             s->last_mv[i][1][0] = mx;
1305                             dmx = get_dmv(s);
1306                             my = mpeg_decode_motion(s, s->mpeg_f_code[i][1], 
1307                                                     s->last_mv[i][0][1] >> 1);
1308                             dmy = get_dmv(s);
1309                             s->mv_type = MV_TYPE_DMV;
1310
1311
1312                             s->last_mv[i][0][1] = my<<1;
1313                             s->last_mv[i][1][1] = my<<1;
1314
1315                             s->mv[i][0][0] = mx;
1316                             s->mv[i][0][1] = my;
1317                             s->mv[i][1][0] = mx;//not used
1318                             s->mv[i][1][1] = my;//not used
1319
1320                             if (s->picture_structure == PICT_FRAME) {
1321                                 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED; 
1322
1323                                 //m = 1 + 2 * s->top_field_first;
1324                                 m = s->top_field_first ? 1 : 3;
1325
1326                                 /* top -> top pred */
1327                                 s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1328                                 s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1329                                 m = 4 - m;
1330                                 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1331                                 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1332                             } else {
1333                                 mb_type |= MB_TYPE_16x16;
1334
1335                                 s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1336                                 s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1337                                 if(s->picture_structure == PICT_TOP_FIELD)
1338                                     s->mv[i][2][1]--;
1339                                 else 
1340                                     s->mv[i][2][1]++;
1341                             }
1342                         }
1343                         break;
1344                     default:
1345                         av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1346                         return -1;
1347                     }
1348                 }
1349             }
1350         }
1351         
1352         s->mb_intra = 0;
1353
1354         if (HAS_CBP(mb_type)) {
1355             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1356             if (cbp < 0 || ((cbp == 0) && (s->chroma_format < 2)) ){
1357                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1358                 return -1;
1359             }
1360             if(mb_block_count > 6){
1361                  cbp<<= mb_block_count-6;
1362                  cbp |= get_bits(&s->gb, mb_block_count-6);
1363             }
1364
1365 #ifdef HAVE_XVMC
1366             //on 1 we memcpy blocks in xvmcvideo
1367             if(s->avctx->xvmc_acceleration > 1){
1368                 XVMC_pack_pblocks(s,cbp);
1369                 if(s->swap_uv){
1370                     exchange_uv(s);
1371                 }
1372             }    
1373 #endif
1374
1375             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
1376                 if(s->flags2 & CODEC_FLAG2_FAST){
1377                     for(i=0;i<6;i++) {
1378                         if(cbp & 32) {
1379                             mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);
1380                         } else {
1381                             s->block_last_index[i] = -1;
1382                         }
1383                         cbp+=cbp;
1384                     }
1385                 }else{
1386                     cbp<<= 12-mb_block_count;
1387     
1388                     for(i=0;i<mb_block_count;i++) {
1389                         if ( cbp & (1<<11) ) {
1390                             if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
1391                                 return -1;
1392                         } else {
1393                             s->block_last_index[i] = -1;
1394                         }
1395                         cbp+=cbp;
1396                     }
1397                 }
1398             } else {
1399                 if(s->flags2 & CODEC_FLAG2_FAST){
1400                     for(i=0;i<6;i++) {
1401                         if (cbp & 32) {
1402                             mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);
1403                         } else {
1404                             s->block_last_index[i] = -1;
1405                         }
1406                         cbp+=cbp;
1407                     }
1408                 }else{
1409                     for(i=0;i<6;i++) {
1410                         if (cbp & 32) {
1411                             if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)
1412                                 return -1;
1413                         } else {
1414                             s->block_last_index[i] = -1;
1415                         }
1416                         cbp+=cbp;
1417                     }
1418                 }
1419             }
1420         }else{
1421             for(i=0;i<6;i++)
1422                 s->block_last_index[i] = -1;
1423         }
1424     }
1425
1426     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
1427
1428     return 0;
1429 }
1430
1431 /* as h263, but only 17 codes */
1432 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
1433 {
1434     int code, sign, val, l, shift;
1435
1436     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
1437     if (code == 0) {
1438         return pred;
1439     }
1440     if (code < 0) {
1441         return 0xffff;
1442     }
1443
1444     sign = get_bits1(&s->gb);
1445     shift = fcode - 1;
1446     val = code;
1447     if (shift) {
1448         val = (val - 1) << shift;
1449         val |= get_bits(&s->gb, shift);
1450         val++;
1451     }
1452     if (sign)
1453         val = -val;
1454     val += pred;
1455     
1456     /* modulo decoding */
1457     l= INT_BIT - 5 - shift;
1458     val = (val<<l)>>l;
1459     return val;
1460 }
1461
1462 static inline int decode_dc(GetBitContext *gb, int component)
1463 {
1464     int code, diff;
1465
1466     if (component == 0) {
1467         code = get_vlc2(gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
1468     } else {
1469         code = get_vlc2(gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
1470     }
1471     if (code < 0){
1472         av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
1473         return 0xffff;
1474     }
1475     if (code == 0) {
1476         diff = 0;
1477     } else {
1478         diff = get_xbits(gb, code);
1479     }
1480     return diff;
1481 }
1482
1483 static inline int mpeg1_decode_block_intra(MpegEncContext *s, 
1484                                DCTELEM *block, 
1485                                int n)
1486 {
1487     int level, dc, diff, i, j, run;
1488     int component;
1489     RLTable *rl = &rl_mpeg1;
1490     uint8_t * const scantable= s->intra_scantable.permutated;
1491     const uint16_t *quant_matrix= s->intra_matrix;
1492     const int qscale= s->qscale;
1493
1494     /* DC coef */
1495     component = (n <= 3 ? 0 : n - 4 + 1);
1496     diff = decode_dc(&s->gb, component);
1497     if (diff >= 0xffff)
1498         return -1;
1499     dc = s->last_dc[component];
1500     dc += diff;
1501     s->last_dc[component] = dc;
1502     block[0] = dc<<3;
1503     dprintf("dc=%d diff=%d\n", dc, diff);
1504     i = 0;
1505     {
1506         OPEN_READER(re, &s->gb);    
1507         /* now quantify & encode AC coefs */
1508         for(;;) {
1509             UPDATE_CACHE(re, &s->gb);
1510             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1511             
1512             if(level == 127){
1513                 break;
1514             } else if(level != 0) {
1515                 i += run;
1516                 j = scantable[i];
1517                 level= (level*qscale*quant_matrix[j])>>4;
1518                 level= (level-1)|1;
1519                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1520                 LAST_SKIP_BITS(re, &s->gb, 1);
1521             } else {
1522                 /* escape */
1523                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1524                 UPDATE_CACHE(re, &s->gb);
1525                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1526                 if (level == -128) {
1527                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1528                 } else if (level == 0) {
1529                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1530                 }
1531                 i += run;
1532                 j = scantable[i];
1533                 if(level<0){
1534                     level= -level;
1535                     level= (level*qscale*quant_matrix[j])>>4;
1536                     level= (level-1)|1;
1537                     level= -level;
1538                 }else{
1539                     level= (level*qscale*quant_matrix[j])>>4;
1540                     level= (level-1)|1;
1541                 }
1542             }
1543             if (i > 63){
1544                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1545                 return -1;
1546             }
1547
1548             block[j] = level;
1549         }
1550         CLOSE_READER(re, &s->gb);
1551     }
1552     s->block_last_index[n] = i;
1553    return 0;
1554 }
1555
1556 static inline int mpeg1_decode_block_inter(MpegEncContext *s, 
1557                                DCTELEM *block, 
1558                                int n)
1559 {
1560     int level, i, j, run;
1561     RLTable *rl = &rl_mpeg1;
1562     uint8_t * const scantable= s->intra_scantable.permutated;
1563     const uint16_t *quant_matrix= s->inter_matrix;
1564     const int qscale= s->qscale;
1565
1566     {
1567         OPEN_READER(re, &s->gb);
1568         i = -1;
1569         /* special case for the first coef. no need to add a second vlc table */
1570         UPDATE_CACHE(re, &s->gb);
1571         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
1572             level= (3*qscale*quant_matrix[0])>>5;
1573             level= (level-1)|1;
1574             if(GET_CACHE(re, &s->gb)&0x40000000)
1575                 level= -level;
1576             block[0] = level;
1577             i++;
1578             SKIP_BITS(re, &s->gb, 2);
1579             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1580                 goto end;
1581         }
1582
1583         /* now quantify & encode AC coefs */
1584         for(;;) {
1585             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1586             
1587             if(level != 0) {
1588                 i += run;
1589                 j = scantable[i];
1590                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1591                 level= (level-1)|1;
1592                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1593                 SKIP_BITS(re, &s->gb, 1);
1594             } else {
1595                 /* escape */
1596                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1597                 UPDATE_CACHE(re, &s->gb);
1598                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1599                 if (level == -128) {
1600                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
1601                 } else if (level == 0) {
1602                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
1603                 }
1604                 i += run;
1605                 j = scantable[i];
1606                 if(level<0){
1607                     level= -level;
1608                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1609                     level= (level-1)|1;
1610                     level= -level;
1611                 }else{
1612                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1613                     level= (level-1)|1;
1614                 }
1615             }
1616             if (i > 63){
1617                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1618                 return -1;
1619             }
1620
1621             block[j] = level;
1622             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1623                 break;
1624             UPDATE_CACHE(re, &s->gb);
1625         }
1626 end:
1627         LAST_SKIP_BITS(re, &s->gb, 2);
1628         CLOSE_READER(re, &s->gb);
1629     }
1630     s->block_last_index[n] = i;
1631     return 0;
1632 }
1633
1634 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
1635 {
1636     int level, i, j, run;
1637     RLTable *rl = &rl_mpeg1;
1638     uint8_t * const scantable= s->intra_scantable.permutated;
1639     const int qscale= s->qscale;
1640
1641     {
1642         OPEN_READER(re, &s->gb);
1643         i = -1;
1644         /* special case for the first coef. no need to add a second vlc table */
1645         UPDATE_CACHE(re, &s->gb);
1646         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
1647             level= (3*qscale)>>1;
1648             level= (level-1)|1;
1649             if(GET_CACHE(re, &s->gb)&0x40000000)
1650                 level= -level;
1651             block[0] = level;
1652             i++;
1653             SKIP_BITS(re, &s->gb, 2);
1654             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1655                 goto end;
1656         }
1657
1658         /* now quantify & encode AC coefs */
1659         for(;;) {
1660             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1661             
1662             if(level != 0) {
1663                 i += run;
1664                 j = scantable[i];
1665                 level= ((level*2+1)*qscale)>>1;
1666                 level= (level-1)|1;
1667                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1668                 SKIP_BITS(re, &s->gb, 1);
1669             } else {
1670                 /* escape */
1671                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1672                 UPDATE_CACHE(re, &s->gb);
1673                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1674                 if (level == -128) {
1675                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
1676                 } else if (level == 0) {
1677                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
1678                 }
1679                 i += run;
1680                 j = scantable[i];
1681                 if(level<0){
1682                     level= -level;
1683                     level= ((level*2+1)*qscale)>>1;
1684                     level= (level-1)|1;
1685                     level= -level;
1686                 }else{
1687                     level= ((level*2+1)*qscale)>>1;
1688                     level= (level-1)|1;
1689                 }
1690             }
1691
1692             block[j] = level;
1693             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1694                 break;
1695             UPDATE_CACHE(re, &s->gb);
1696         }
1697 end:
1698         LAST_SKIP_BITS(re, &s->gb, 2);
1699         CLOSE_READER(re, &s->gb);
1700     }
1701     s->block_last_index[n] = i;
1702     return 0;
1703 }
1704
1705
1706 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, 
1707                                DCTELEM *block, 
1708                                int n)
1709 {
1710     int level, i, j, run;
1711     RLTable *rl = &rl_mpeg1;
1712     uint8_t * const scantable= s->intra_scantable.permutated;
1713     const uint16_t *quant_matrix;
1714     const int qscale= s->qscale;
1715     int mismatch;
1716
1717     mismatch = 1;
1718
1719     {
1720         OPEN_READER(re, &s->gb);
1721         i = -1;
1722         if (n < 4)
1723             quant_matrix = s->inter_matrix;
1724         else
1725             quant_matrix = s->chroma_inter_matrix;
1726
1727         /* special case for the first coef. no need to add a second vlc table */
1728         UPDATE_CACHE(re, &s->gb);
1729         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
1730             level= (3*qscale*quant_matrix[0])>>5;
1731             if(GET_CACHE(re, &s->gb)&0x40000000)
1732                 level= -level;
1733             block[0] = level;
1734             mismatch ^= level;
1735             i++;
1736             SKIP_BITS(re, &s->gb, 2);
1737             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1738                 goto end;
1739         }
1740
1741         /* now quantify & encode AC coefs */
1742         for(;;) {
1743             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1744             
1745             if(level != 0) {
1746                 i += run;
1747                 j = scantable[i];
1748                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1749                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1750                 SKIP_BITS(re, &s->gb, 1);
1751             } else {
1752                 /* escape */
1753                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1754                 UPDATE_CACHE(re, &s->gb);
1755                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1756
1757                 i += run;
1758                 j = scantable[i];
1759                 if(level<0){
1760                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
1761                     level= -level;
1762                 }else{
1763                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1764                 }
1765             }
1766             if (i > 63){
1767                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1768                 return -1;
1769             }
1770             
1771             mismatch ^= level;
1772             block[j] = level;
1773             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1774                 break;
1775             UPDATE_CACHE(re, &s->gb);
1776         }
1777 end:
1778         LAST_SKIP_BITS(re, &s->gb, 2);
1779         CLOSE_READER(re, &s->gb);
1780     }
1781     block[63] ^= (mismatch & 1);
1782     
1783     s->block_last_index[n] = i;
1784     return 0;
1785 }
1786
1787 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, 
1788                                DCTELEM *block, 
1789                                int n)
1790 {
1791     int level, i, j, run;
1792     RLTable *rl = &rl_mpeg1;
1793     uint8_t * const scantable= s->intra_scantable.permutated;
1794     const int qscale= s->qscale;
1795     int v;
1796     OPEN_READER(re, &s->gb);
1797     i = -1;
1798
1799     /* special case for the first coef. no need to add a second vlc table */
1800     UPDATE_CACHE(re, &s->gb);
1801     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
1802         level= (3*qscale)>>1;
1803         if(GET_CACHE(re, &s->gb)&0x40000000)
1804             level= -level;
1805         block[0] = level;
1806         i++;
1807         SKIP_BITS(re, &s->gb, 2);
1808         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1809             goto end;
1810     }
1811
1812     /* now quantify & encode AC coefs */
1813     for(;;) {
1814         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1815         
1816         if(level != 0) {
1817             i += run;
1818             j = scantable[i];
1819             level= ((level*2+1)*qscale)>>1;
1820             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1821             SKIP_BITS(re, &s->gb, 1);
1822         } else {
1823             /* escape */
1824             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1825             UPDATE_CACHE(re, &s->gb);
1826             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1827
1828             i += run;
1829             j = scantable[i];
1830             if(level<0){
1831                 level= ((-level*2+1)*qscale)>>1;
1832                 level= -level;
1833             }else{
1834                 level= ((level*2+1)*qscale)>>1;
1835             }
1836         }
1837         
1838         block[j] = level;
1839         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1840             break;
1841         UPDATE_CACHE(re, &s->gb);
1842     }
1843 end:
1844     LAST_SKIP_BITS(re, &s->gb, 2);    
1845     CLOSE_READER(re, &s->gb);
1846     s->block_last_index[n] = i;
1847     return 0;
1848 }
1849
1850
1851 static inline int mpeg2_decode_block_intra(MpegEncContext *s, 
1852                                DCTELEM *block, 
1853                                int n)
1854 {
1855     int level, dc, diff, i, j, run;
1856     int component;
1857     RLTable *rl;
1858     uint8_t * const scantable= s->intra_scantable.permutated;
1859     const uint16_t *quant_matrix;
1860     const int qscale= s->qscale;
1861     int mismatch;
1862
1863     /* DC coef */
1864     if (n < 4){
1865         quant_matrix = s->intra_matrix;
1866         component = 0; 
1867     }else{
1868         quant_matrix = s->chroma_intra_matrix;
1869         component = (n&1) + 1;
1870     }
1871     diff = decode_dc(&s->gb, component);
1872     if (diff >= 0xffff)
1873         return -1;
1874     dc = s->last_dc[component];
1875     dc += diff;
1876     s->last_dc[component] = dc;
1877     block[0] = dc << (3 - s->intra_dc_precision);
1878     dprintf("dc=%d\n", block[0]);
1879     mismatch = block[0] ^ 1;
1880     i = 0;
1881     if (s->intra_vlc_format)
1882         rl = &rl_mpeg2;
1883     else
1884         rl = &rl_mpeg1;
1885
1886     {
1887         OPEN_READER(re, &s->gb);    
1888         /* now quantify & encode AC coefs */
1889         for(;;) {
1890             UPDATE_CACHE(re, &s->gb);
1891             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1892             
1893             if(level == 127){
1894                 break;
1895             } else if(level != 0) {
1896                 i += run;
1897                 j = scantable[i];
1898                 level= (level*qscale*quant_matrix[j])>>4;
1899                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1900                 LAST_SKIP_BITS(re, &s->gb, 1);
1901             } else {
1902                 /* escape */
1903                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1904                 UPDATE_CACHE(re, &s->gb);
1905                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1906                 i += run;
1907                 j = scantable[i];
1908                 if(level<0){
1909                     level= (-level*qscale*quant_matrix[j])>>4;
1910                     level= -level;
1911                 }else{
1912                     level= (level*qscale*quant_matrix[j])>>4;
1913                 }
1914             }
1915             if (i > 63){
1916                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1917                 return -1;
1918             }
1919             
1920             mismatch^= level;
1921             block[j] = level;
1922         }
1923         CLOSE_READER(re, &s->gb);
1924     }
1925     block[63]^= mismatch&1;
1926     
1927     s->block_last_index[n] = i;
1928     return 0;
1929 }
1930
1931 typedef struct Mpeg1Context {
1932     MpegEncContext mpeg_enc_ctx;
1933     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1934     int repeat_field; /* true if we must repeat the field */
1935     AVPanScan pan_scan; /** some temporary storage for the panscan */
1936     int slice_count;
1937     int swap_uv;//indicate VCR2
1938     int save_aspect_info;
1939     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1940
1941 } Mpeg1Context;
1942
1943 static int mpeg_decode_init(AVCodecContext *avctx)
1944 {
1945     Mpeg1Context *s = avctx->priv_data;
1946     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1947     int i;
1948     
1949     //we need some parmutation to store
1950     //matrixes, until MPV_common_init()
1951     //set the real permutatuon 
1952     for(i=0;i<64;i++)
1953        s2->dsp.idct_permutation[i]=i;
1954
1955     MPV_decode_defaults(s2);
1956     
1957     s->mpeg_enc_ctx.avctx= avctx;
1958     s->mpeg_enc_ctx.flags= avctx->flags;
1959     s->mpeg_enc_ctx.flags2= avctx->flags2;
1960     common_init(&s->mpeg_enc_ctx);
1961     init_vlcs();
1962
1963     s->mpeg_enc_ctx_allocated = 0;
1964     s->mpeg_enc_ctx.picture_number = 0;
1965     s->repeat_field = 0;
1966     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1967     return 0;
1968 }
1969
1970 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm, 
1971                                      const uint8_t *new_perm){
1972     uint16_t temp_matrix[64];
1973     int i;
1974
1975     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1976     
1977     for(i=0;i<64;i++){
1978         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1979     }      
1980 }
1981
1982 //Call this function when we know all parameters
1983 //it may be called in different places for mpeg1 and mpeg2
1984 static int mpeg_decode_postinit(AVCodecContext *avctx){
1985     Mpeg1Context *s1 = avctx->priv_data;
1986     MpegEncContext *s = &s1->mpeg_enc_ctx;
1987     uint8_t old_permutation[64];
1988
1989     if (
1990         (s1->mpeg_enc_ctx_allocated == 0)|| 
1991         avctx->coded_width  != s->width ||
1992         avctx->coded_height != s->height||
1993         s1->save_aspect_info != s->aspect_ratio_info||
1994         0)
1995     {
1996     
1997         if (s1->mpeg_enc_ctx_allocated) {
1998             MPV_common_end(s);
1999         }
2000
2001         if( (s->width == 0 )||(s->height == 0))
2002             return -2;
2003
2004         avcodec_set_dimensions(avctx, s->width, s->height);
2005         avctx->bit_rate = s->bit_rate;
2006         s1->save_aspect_info = s->aspect_ratio_info;
2007
2008      //low_delay may be forced, in this case we will have B frames
2009      //that behave like P frames
2010         avctx->has_b_frames = !(s->low_delay);
2011
2012         if(avctx->sub_id==1){//s->codec_id==avctx->codec_id==CODEC_ID
2013             //mpeg1 fps
2014             avctx->frame_rate     = frame_rate_tab[s->frame_rate_index].num;
2015             avctx->frame_rate_base= frame_rate_tab[s->frame_rate_index].den;
2016             //mpeg1 aspect
2017             avctx->sample_aspect_ratio= av_d2q(
2018                     1.0/mpeg1_aspect[s->aspect_ratio_info], 255);
2019
2020         }else{//mpeg2
2021         //mpeg2 fps
2022             av_reduce(
2023                 &s->avctx->frame_rate, 
2024                 &s->avctx->frame_rate_base, 
2025                 frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
2026                 frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
2027                 1<<30);
2028         //mpeg2 aspect
2029             if(s->aspect_ratio_info > 1){
2030                 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) ){
2031                     s->avctx->sample_aspect_ratio= 
2032                         av_div_q(
2033                          mpeg2_aspect[s->aspect_ratio_info], 
2034                          (AVRational){s->width, s->height}
2035                          );
2036                 }else{
2037                     s->avctx->sample_aspect_ratio= 
2038                         av_div_q(
2039                          mpeg2_aspect[s->aspect_ratio_info], 
2040                          (AVRational){s1->pan_scan.width, s1->pan_scan.height}
2041                         );
2042                 }
2043             }else{
2044                 s->avctx->sample_aspect_ratio= 
2045                     mpeg2_aspect[s->aspect_ratio_info];
2046             }
2047         }//mpeg2
2048
2049         if(avctx->xvmc_acceleration){
2050             avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
2051         }else{
2052             if(s->chroma_format <  2){
2053                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
2054             }else
2055             if(s->chroma_format == 2){
2056                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_422);
2057             }else
2058             if(s->chroma_format >  2){
2059                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_444);
2060             }
2061         }
2062         //until then pix_fmt may be changed right after codec init
2063         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
2064             if( avctx->idct_algo == FF_IDCT_AUTO )
2065                 avctx->idct_algo = FF_IDCT_SIMPLE;
2066
2067         //quantization matrixes may need reordering 
2068         //if dct permutation is changed
2069         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
2070
2071         if (MPV_common_init(s) < 0)
2072             return -2;
2073
2074         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
2075         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
2076         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
2077         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
2078
2079         s1->mpeg_enc_ctx_allocated = 1;
2080     }
2081     return 0;
2082 }
2083
2084 /* return the 8 bit start code value and update the search
2085    state. Return -1 if no start code found */
2086 static int find_start_code(const uint8_t **pbuf_ptr, const uint8_t *buf_end)
2087 {
2088     const uint8_t *buf_ptr= *pbuf_ptr;
2089
2090     buf_ptr++; //gurantees that -1 is within the array
2091     buf_end -= 2; // gurantees that +2 is within the array
2092
2093     while (buf_ptr < buf_end) {
2094         if(*buf_ptr==0){
2095             while(buf_ptr < buf_end && buf_ptr[1]==0)
2096                 buf_ptr++;
2097
2098             if(buf_ptr[-1] == 0 && buf_ptr[1] == 1){
2099                 *pbuf_ptr = buf_ptr+3;
2100                 return buf_ptr[2] + 0x100;
2101             }
2102         }
2103         buf_ptr += 2;
2104     }
2105     buf_end += 2; //undo the hack above
2106     
2107     *pbuf_ptr = buf_end;
2108     return -1;
2109 }
2110
2111 static int mpeg1_decode_picture(AVCodecContext *avctx, 
2112                                 const uint8_t *buf, int buf_size)
2113 {
2114     Mpeg1Context *s1 = avctx->priv_data;
2115     MpegEncContext *s = &s1->mpeg_enc_ctx;
2116     int ref, f_code, vbv_delay;
2117
2118     if(mpeg_decode_postinit(s->avctx) < 0) 
2119        return -2;
2120
2121     init_get_bits(&s->gb, buf, buf_size*8);
2122
2123     ref = get_bits(&s->gb, 10); /* temporal ref */
2124     s->pict_type = get_bits(&s->gb, 3);
2125     if(s->pict_type == 0 || s->pict_type > 3)
2126         return -1;
2127
2128     vbv_delay= get_bits(&s->gb, 16);
2129     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
2130         s->full_pel[0] = get_bits1(&s->gb);
2131         f_code = get_bits(&s->gb, 3);
2132         if (f_code == 0)
2133             return -1;
2134         s->mpeg_f_code[0][0] = f_code;
2135         s->mpeg_f_code[0][1] = f_code;
2136     }
2137     if (s->pict_type == B_TYPE) {
2138         s->full_pel[1] = get_bits1(&s->gb);
2139         f_code = get_bits(&s->gb, 3);
2140         if (f_code == 0)
2141             return -1;
2142         s->mpeg_f_code[1][0] = f_code;
2143         s->mpeg_f_code[1][1] = f_code;
2144     }
2145     s->current_picture.pict_type= s->pict_type;
2146     s->current_picture.key_frame= s->pict_type == I_TYPE;
2147     
2148     if(avctx->debug & FF_DEBUG_PICT_INFO)
2149         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
2150     
2151     s->y_dc_scale = 8;
2152     s->c_dc_scale = 8;
2153     s->first_slice = 1;
2154     return 0;
2155 }
2156
2157 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
2158 {
2159     MpegEncContext *s= &s1->mpeg_enc_ctx;
2160     int horiz_size_ext, vert_size_ext;
2161     int bit_rate_ext;
2162
2163     skip_bits(&s->gb, 1); /* profil and level esc*/
2164     s->avctx->profile= get_bits(&s->gb, 3);
2165     s->avctx->level= get_bits(&s->gb, 4);
2166     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
2167     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
2168     horiz_size_ext = get_bits(&s->gb, 2);
2169     vert_size_ext = get_bits(&s->gb, 2);
2170     s->width |= (horiz_size_ext << 12);
2171     s->height |= (vert_size_ext << 12);
2172     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
2173     s->bit_rate += (bit_rate_ext << 18) * 400;
2174     skip_bits1(&s->gb); /* marker */
2175     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
2176
2177     s->low_delay = get_bits1(&s->gb);
2178     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2179
2180     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
2181     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
2182
2183     dprintf("sequence extension\n");
2184     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2185     s->avctx->sub_id = 2; /* indicates mpeg2 found */
2186
2187     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2188         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n", 
2189                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
2190
2191 }
2192
2193 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
2194 {
2195     MpegEncContext *s= &s1->mpeg_enc_ctx;
2196     int color_description, w, h;
2197
2198     skip_bits(&s->gb, 3); /* video format */
2199     color_description= get_bits1(&s->gb);
2200     if(color_description){
2201         skip_bits(&s->gb, 8); /* color primaries */
2202         skip_bits(&s->gb, 8); /* transfer_characteristics */
2203         skip_bits(&s->gb, 8); /* matrix_coefficients */
2204     }
2205     w= get_bits(&s->gb, 14);
2206     skip_bits(&s->gb, 1); //marker
2207     h= get_bits(&s->gb, 14);
2208     skip_bits(&s->gb, 1); //marker
2209     
2210     s1->pan_scan.width= 16*w;
2211     s1->pan_scan.height=16*h;
2212         
2213     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2214         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
2215 }
2216
2217 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
2218 {
2219     MpegEncContext *s= &s1->mpeg_enc_ctx;
2220     int i,nofco;
2221
2222     nofco = 1;
2223     if(s->progressive_sequence){
2224         if(s->repeat_first_field){
2225             nofco++;
2226             if(s->top_field_first)
2227                 nofco++;        
2228         }
2229     }else{
2230         if(s->picture_structure == PICT_FRAME){
2231             nofco++;
2232             if(s->repeat_first_field)
2233                 nofco++;
2234         }
2235     }
2236     for(i=0; i<nofco; i++){
2237         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
2238         skip_bits(&s->gb, 1); //marker
2239         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
2240         skip_bits(&s->gb, 1); //marker
2241     }
2242    
2243     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2244         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n", 
2245             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1], 
2246             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1], 
2247             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
2248         );
2249 }
2250
2251 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
2252 {
2253     int i, v, j;
2254
2255     dprintf("matrix extension\n");
2256
2257     if (get_bits1(&s->gb)) {
2258         for(i=0;i<64;i++) {
2259             v = get_bits(&s->gb, 8);
2260             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2261             s->intra_matrix[j] = v;
2262             s->chroma_intra_matrix[j] = v;
2263         }
2264     }
2265     if (get_bits1(&s->gb)) {
2266         for(i=0;i<64;i++) {
2267             v = get_bits(&s->gb, 8);
2268             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2269             s->inter_matrix[j] = v;
2270             s->chroma_inter_matrix[j] = v;
2271         }
2272     }
2273     if (get_bits1(&s->gb)) {
2274         for(i=0;i<64;i++) {
2275             v = get_bits(&s->gb, 8);
2276             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2277             s->chroma_intra_matrix[j] = v;
2278         }
2279     }
2280     if (get_bits1(&s->gb)) {
2281         for(i=0;i<64;i++) {
2282             v = get_bits(&s->gb, 8);
2283             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2284             s->chroma_inter_matrix[j] = v;
2285         }
2286     }
2287 }
2288
2289 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
2290 {
2291     s->full_pel[0] = s->full_pel[1] = 0;
2292     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
2293     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
2294     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
2295     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
2296     s->intra_dc_precision = get_bits(&s->gb, 2);
2297     s->picture_structure = get_bits(&s->gb, 2);
2298     s->top_field_first = get_bits1(&s->gb);
2299     s->frame_pred_frame_dct = get_bits1(&s->gb);
2300     s->concealment_motion_vectors = get_bits1(&s->gb);
2301     s->q_scale_type = get_bits1(&s->gb);
2302     s->intra_vlc_format = get_bits1(&s->gb);
2303     s->alternate_scan = get_bits1(&s->gb);
2304     s->repeat_first_field = get_bits1(&s->gb);
2305     s->chroma_420_type = get_bits1(&s->gb);
2306     s->progressive_frame = get_bits1(&s->gb);
2307
2308     if(s->picture_structure == PICT_FRAME)
2309         s->first_field=0;
2310     else{
2311         s->first_field ^= 1;
2312         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
2313     }
2314     
2315     if(s->alternate_scan){
2316         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
2317         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
2318     }else{
2319         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
2320         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
2321     }
2322     
2323     /* composite display not parsed */
2324     dprintf("intra_dc_precision=%d\n", s->intra_dc_precision);
2325     dprintf("picture_structure=%d\n", s->picture_structure);
2326     dprintf("top field first=%d\n", s->top_field_first);
2327     dprintf("repeat first field=%d\n", s->repeat_first_field);
2328     dprintf("conceal=%d\n", s->concealment_motion_vectors);
2329     dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
2330     dprintf("alternate_scan=%d\n", s->alternate_scan);
2331     dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
2332     dprintf("progressive_frame=%d\n", s->progressive_frame);
2333 }
2334
2335 static void mpeg_decode_extension(AVCodecContext *avctx, 
2336                                   const uint8_t *buf, int buf_size)
2337 {
2338     Mpeg1Context *s1 = avctx->priv_data;
2339     MpegEncContext *s = &s1->mpeg_enc_ctx;
2340     int ext_type;
2341
2342     init_get_bits(&s->gb, buf, buf_size*8);
2343     
2344     ext_type = get_bits(&s->gb, 4);
2345     switch(ext_type) {
2346     case 0x1:
2347         mpeg_decode_sequence_extension(s1);
2348         break;
2349     case 0x2:
2350         mpeg_decode_sequence_display_extension(s1);
2351         break;
2352     case 0x3:
2353         mpeg_decode_quant_matrix_extension(s);
2354         break;
2355     case 0x7:
2356         mpeg_decode_picture_display_extension(s1);
2357         break;
2358     case 0x8:
2359         mpeg_decode_picture_coding_extension(s);
2360         break;
2361     }
2362 }
2363
2364 static void exchange_uv(MpegEncContext *s){
2365     short * tmp = s->pblocks[4];
2366     s->pblocks[4] = s->pblocks[5];
2367     s->pblocks[5] = tmp;
2368 }
2369
2370 static int mpeg_field_start(MpegEncContext *s){
2371     AVCodecContext *avctx= s->avctx;
2372     Mpeg1Context *s1 = (Mpeg1Context*)s;
2373
2374     /* start frame decoding */
2375     if(s->first_field || s->picture_structure==PICT_FRAME){
2376         if(MPV_frame_start(s, avctx) < 0)
2377             return -1;
2378
2379         ff_er_frame_start(s);
2380
2381         /* first check if we must repeat the frame */
2382         s->current_picture_ptr->repeat_pict = 0;
2383         if (s->repeat_first_field) {
2384             if (s->progressive_sequence) {
2385                 if (s->top_field_first)
2386                     s->current_picture_ptr->repeat_pict = 4;
2387                 else
2388                     s->current_picture_ptr->repeat_pict = 2;
2389             } else if (s->progressive_frame) {
2390                 s->current_picture_ptr->repeat_pict = 1;
2391             }
2392         }         
2393
2394         *s->current_picture_ptr->pan_scan= s1->pan_scan;
2395     }else{ //second field
2396             int i;
2397             
2398             if(!s->current_picture_ptr){
2399                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
2400                 return -1;
2401             }
2402             
2403             for(i=0; i<4; i++){
2404                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
2405                 if(s->picture_structure == PICT_BOTTOM_FIELD){
2406                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
2407                 } 
2408             }
2409     }
2410 #ifdef HAVE_XVMC
2411 // MPV_frame_start will call this function too,
2412 // but we need to call it on every field
2413     if(s->avctx->xvmc_acceleration)
2414          XVMC_field_start(s,avctx);
2415 #endif
2416
2417     return 0;
2418 }
2419
2420 #define DECODE_SLICE_ERROR -1
2421 #define DECODE_SLICE_OK 0
2422
2423 /**
2424  * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
2425  * @return DECODE_SLICE_ERROR if the slice is damaged<br>
2426  *         DECODE_SLICE_OK if this slice is ok<br>
2427  */
2428 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
2429                              const uint8_t **buf, int buf_size)
2430 {
2431     MpegEncContext *s = &s1->mpeg_enc_ctx;
2432     AVCodecContext *avctx= s->avctx;
2433     int ret;
2434     const int field_pic= s->picture_structure != PICT_FRAME;
2435     const int lowres= s->avctx->lowres;
2436
2437     s->resync_mb_x=
2438     s->resync_mb_y= -1;
2439
2440     if (mb_y<<field_pic >= s->mb_height){
2441         av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
2442         return -1;
2443     }
2444     
2445     init_get_bits(&s->gb, *buf, buf_size*8);
2446
2447     ff_mpeg1_clean_buffers(s);
2448     s->interlaced_dct = 0;
2449
2450     s->qscale = get_qscale(s);
2451
2452     if(s->qscale == 0){
2453         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
2454         return -1;
2455     }
2456     
2457     /* extra slice info */
2458     while (get_bits1(&s->gb) != 0) {
2459         skip_bits(&s->gb, 8);
2460     }
2461     
2462     s->mb_x=0;
2463
2464     for(;;) {
2465         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
2466         if (code < 0){
2467             av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
2468             return -1;
2469         }
2470         if (code >= 33) {
2471             if (code == 33) {
2472                 s->mb_x += 33;
2473             }
2474             /* otherwise, stuffing, nothing to do */
2475         } else {
2476             s->mb_x += code;
2477             break;
2478         }
2479     }
2480
2481     s->resync_mb_x= s->mb_x;
2482     s->resync_mb_y= s->mb_y= mb_y;
2483     s->mb_skip_run= 0;
2484     ff_init_block_index(s);
2485
2486     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
2487         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
2488              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", 
2489                  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],
2490                  s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")), 
2491                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"", 
2492                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
2493                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
2494         }
2495     }    
2496     
2497     for(;;) {
2498 #ifdef HAVE_XVMC
2499         //one 1 we memcpy blocks in xvmcvideo
2500         if(s->avctx->xvmc_acceleration > 1)
2501             XVMC_init_block(s);//set s->block
2502 #endif
2503
2504         s->dsp.clear_blocks(s->block[0]);
2505         if(!s->chroma_y_shift){
2506             s->dsp.clear_blocks(s->block[6]);
2507         }
2508         ret = mpeg_decode_mb(s, s->block);
2509         s->chroma_qscale= s->qscale;
2510
2511         dprintf("ret=%d\n", ret);
2512         if (ret < 0)
2513             return -1;
2514
2515         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
2516             const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
2517             int xy = s->mb_x*2 + s->mb_y*2*wrap;
2518             int motion_x, motion_y, dir, i;
2519             if(field_pic && !s->first_field)
2520                 xy += wrap/2;
2521
2522             for(i=0; i<2; i++){
2523                 for(dir=0; dir<2; dir++){
2524                     if (s->mb_intra || (dir==1 && s->pict_type != B_TYPE)) {
2525                         motion_x = motion_y = 0;
2526                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
2527                         motion_x = s->mv[dir][0][0];
2528                         motion_y = s->mv[dir][0][1];
2529                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
2530                         motion_x = s->mv[dir][i][0];
2531                         motion_y = s->mv[dir][i][1];
2532                     }
2533
2534                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
2535                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
2536                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
2537                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
2538                     s->current_picture.ref_index [dir][xy    ]=
2539                     s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
2540                 }
2541                 xy += wrap;
2542             }
2543         }
2544
2545         s->dest[0] += 16 >> lowres;
2546         s->dest[1] += 16 >> (s->chroma_x_shift + lowres);
2547         s->dest[2] += 16 >> (s->chroma_x_shift + lowres);
2548
2549         MPV_decode_mb(s, s->block);
2550         
2551         if (++s->mb_x >= s->mb_width) {
2552             const int mb_size= 16>>s->avctx->lowres;
2553
2554             ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
2555
2556             s->mb_x = 0;
2557             s->mb_y++;
2558
2559             if(s->mb_y<<field_pic >= s->mb_height){
2560                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
2561
2562                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)))
2563                    || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
2564                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d\n", left);
2565                     return -1;
2566                 }else
2567                     goto eos;
2568             }
2569             
2570             ff_init_block_index(s);
2571         }
2572
2573         /* skip mb handling */
2574         if (s->mb_skip_run == -1) {
2575             /* read again increment */
2576             s->mb_skip_run = 0;
2577             for(;;) {
2578                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
2579                 if (code < 0){
2580                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
2581                     return -1;
2582                 }
2583                 if (code >= 33) {
2584                     if (code == 33) {
2585                         s->mb_skip_run += 33;
2586                     }else if(code == 35){
2587                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
2588                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
2589                             return -1;
2590                         }
2591                         goto eos; /* end of slice */
2592                     }
2593                     /* otherwise, stuffing, nothing to do */
2594                 } else {
2595                     s->mb_skip_run += code;
2596                     break;
2597                 }
2598             }
2599         }
2600     }
2601 eos: // end of slice
2602     *buf += get_bits_count(&s->gb)/8 - 1;
2603 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
2604     return 0;
2605 }
2606
2607 static int slice_decode_thread(AVCodecContext *c, void *arg){
2608     MpegEncContext *s= arg;
2609     const uint8_t *buf= s->gb.buffer;
2610     int mb_y= s->start_mb_y;
2611
2612     s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
2613
2614     for(;;){
2615         int start_code, ret;
2616
2617         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
2618         emms_c();
2619 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n", 
2620 //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);
2621         if(ret < 0){
2622             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
2623                 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);
2624         }else{
2625             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);
2626         }
2627         
2628         if(s->mb_y == s->end_mb_y)
2629             return 0;
2630         
2631         start_code = find_start_code(&buf, s->gb.buffer_end);
2632         mb_y= start_code - SLICE_MIN_START_CODE;
2633         if(mb_y < 0 || mb_y >= s->end_mb_y)
2634             return -1;
2635     }
2636     
2637     return 0; //not reached
2638 }
2639
2640 /**
2641  * handles slice ends.
2642  * @return 1 if it seems to be the last slice of 
2643  */
2644 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2645 {
2646     Mpeg1Context *s1 = avctx->priv_data;
2647     MpegEncContext *s = &s1->mpeg_enc_ctx;
2648        
2649     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2650         return 0;
2651
2652 #ifdef HAVE_XVMC
2653     if(s->avctx->xvmc_acceleration)
2654         XVMC_field_end(s);
2655 #endif
2656     /* end of slice reached */
2657     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
2658         /* end of image */
2659
2660         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
2661
2662         ff_er_frame_end(s);
2663
2664         MPV_frame_end(s);
2665
2666         if (s->pict_type == B_TYPE || s->low_delay) {
2667             *pict= *(AVFrame*)s->current_picture_ptr;
2668             ff_print_debug_info(s, pict);
2669         } else {
2670             s->picture_number++;
2671             /* latency of 1 frame for I and P frames */
2672             /* XXX: use another variable than picture_number */
2673             if (s->last_picture_ptr != NULL) {
2674                 *pict= *(AVFrame*)s->last_picture_ptr;
2675                  ff_print_debug_info(s, pict);
2676             }
2677         }
2678
2679         return 1;
2680     } else {
2681         return 0;
2682     }
2683 }
2684
2685 static int mpeg1_decode_sequence(AVCodecContext *avctx, 
2686                                  const uint8_t *buf, int buf_size)
2687 {
2688     Mpeg1Context *s1 = avctx->priv_data;
2689     MpegEncContext *s = &s1->mpeg_enc_ctx;
2690     int width,height;
2691     int i, v, j;
2692
2693     init_get_bits(&s->gb, buf, buf_size*8);
2694
2695     width = get_bits(&s->gb, 12);
2696     height = get_bits(&s->gb, 12);
2697     if (width <= 0 || height <= 0 ||
2698         (width % 2) != 0 || (height % 2) != 0)
2699         return -1;
2700     s->aspect_ratio_info= get_bits(&s->gb, 4);
2701     if (s->aspect_ratio_info == 0)
2702         return -1;
2703     s->frame_rate_index = get_bits(&s->gb, 4);
2704     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
2705         return -1;
2706     s->bit_rate = get_bits(&s->gb, 18) * 400;
2707     if (get_bits1(&s->gb) == 0) /* marker */
2708         return -1;
2709     s->width = width;
2710     s->height = height;
2711
2712     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
2713     skip_bits(&s->gb, 1);
2714
2715     /* get matrix */
2716     if (get_bits1(&s->gb)) {
2717         for(i=0;i<64;i++) {
2718             v = get_bits(&s->gb, 8);
2719             if(v==0){
2720                 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
2721                 return -1;
2722             }
2723             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2724             s->intra_matrix[j] = v;
2725             s->chroma_intra_matrix[j] = v;
2726         }
2727 #ifdef DEBUG
2728         dprintf("intra matrix present\n");
2729         for(i=0;i<64;i++)
2730             dprintf(" %d", s->intra_matrix[s->dsp.idct_permutation[i]]);
2731         printf("\n");
2732 #endif
2733     } else {
2734         for(i=0;i<64;i++) {
2735             j = s->dsp.idct_permutation[i];
2736             v = ff_mpeg1_default_intra_matrix[i];
2737             s->intra_matrix[j] = v;
2738             s->chroma_intra_matrix[j] = v;
2739         }
2740     }
2741     if (get_bits1(&s->gb)) {
2742         for(i=0;i<64;i++) {
2743             v = get_bits(&s->gb, 8);
2744             if(v==0){
2745                 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
2746                 return -1;
2747             }
2748             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2749             s->inter_matrix[j] = v;
2750             s->chroma_inter_matrix[j] = v;
2751         }
2752 #ifdef DEBUG
2753         dprintf("non intra matrix present\n");
2754         for(i=0;i<64;i++)
2755             dprintf(" %d", s->inter_matrix[s->dsp.idct_permutation[i]]);
2756         printf("\n");
2757 #endif
2758     } else {
2759         for(i=0;i<64;i++) {
2760             int j= s->dsp.idct_permutation[i];
2761             v = ff_mpeg1_default_non_intra_matrix[i];
2762             s->inter_matrix[j] = v;
2763             s->chroma_inter_matrix[j] = v;
2764         }
2765     }
2766     
2767     if(show_bits(&s->gb, 23) != 0){
2768         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2769         return -1;
2770     }
2771
2772     /* we set mpeg2 parameters so that it emulates mpeg1 */
2773     s->progressive_sequence = 1;
2774     s->progressive_frame = 1;
2775     s->picture_structure = PICT_FRAME;
2776     s->frame_pred_frame_dct = 1;
2777     s->chroma_format = 1;
2778     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2779     avctx->sub_id = 1; /* indicates mpeg1 */
2780     s->out_format = FMT_MPEG1;
2781     s->swap_uv = 0;//AFAIK VCR2 don't have SEQ_HEADER
2782     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2783     
2784     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2785         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n", 
2786                s->avctx->rc_buffer_size, s->bit_rate);
2787     
2788     return 0;
2789 }
2790
2791 static int vcr2_init_sequence(AVCodecContext *avctx)
2792 {
2793     Mpeg1Context *s1 = avctx->priv_data;
2794     MpegEncContext *s = &s1->mpeg_enc_ctx;
2795     int i, v;
2796
2797     /* start new mpeg1 context decoding */
2798     s->out_format = FMT_MPEG1;
2799     if (s1->mpeg_enc_ctx_allocated) {
2800         MPV_common_end(s);
2801     }
2802     s->width  = avctx->coded_width;
2803     s->height = avctx->coded_height;
2804     avctx->has_b_frames= 0; //true?
2805     s->low_delay= 1;
2806
2807     if(avctx->xvmc_acceleration){
2808         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
2809     }else{
2810         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
2811     }
2812
2813     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
2814         if( avctx->idct_algo == FF_IDCT_AUTO )
2815             avctx->idct_algo = FF_IDCT_SIMPLE;
2816     
2817     if (MPV_common_init(s) < 0)
2818         return -1;
2819     exchange_uv(s);//common init reset pblocks, so we swap them here
2820     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB 
2821     s1->mpeg_enc_ctx_allocated = 1;
2822
2823     for(i=0;i<64;i++) {
2824         int j= s->dsp.idct_permutation[i];
2825         v = ff_mpeg1_default_intra_matrix[i];
2826         s->intra_matrix[j] = v;
2827         s->chroma_intra_matrix[j] = v;
2828
2829         v = ff_mpeg1_default_non_intra_matrix[i];
2830         s->inter_matrix[j] = v;
2831         s->chroma_inter_matrix[j] = v;
2832     }
2833
2834     s->progressive_sequence = 1;
2835     s->progressive_frame = 1;
2836     s->picture_structure = PICT_FRAME;
2837     s->frame_pred_frame_dct = 1;
2838     s->chroma_format = 1;
2839     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2840     avctx->sub_id = 2; /* indicates mpeg2 */
2841     return 0;
2842 }
2843
2844
2845 static void mpeg_decode_user_data(AVCodecContext *avctx, 
2846                                   const uint8_t *buf, int buf_size)
2847 {
2848     const uint8_t *p;
2849     int len, flags;
2850     p = buf;
2851     len = buf_size;
2852
2853     /* we parse the DTG active format information */
2854     if (len >= 5 &&
2855         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2856         flags = p[4];
2857         p += 5;
2858         len -= 5;
2859         if (flags & 0x80) {
2860             /* skip event id */
2861             if (len < 2)
2862                 return;
2863             p += 2;
2864             len -= 2;
2865         }
2866         if (flags & 0x40) {
2867             if (len < 1)
2868                 return;
2869             avctx->dtg_active_format = p[0] & 0x0f;
2870         }
2871     }
2872 }
2873
2874 static void mpeg_decode_gop(AVCodecContext *avctx, 
2875                             const uint8_t *buf, int buf_size){
2876     Mpeg1Context *s1 = avctx->priv_data;
2877     MpegEncContext *s = &s1->mpeg_enc_ctx;
2878
2879     int drop_frame_flag;
2880     int time_code_hours, time_code_minutes;
2881     int time_code_seconds, time_code_pictures;
2882     int broken_link;
2883
2884     init_get_bits(&s->gb, buf, buf_size*8);
2885
2886     drop_frame_flag = get_bits1(&s->gb);
2887     
2888     time_code_hours=get_bits(&s->gb,5);
2889     time_code_minutes = get_bits(&s->gb,6);
2890     skip_bits1(&s->gb);//marker bit
2891     time_code_seconds = get_bits(&s->gb,6);
2892     time_code_pictures = get_bits(&s->gb,6);
2893
2894     /*broken_link indicate that after editing the
2895       reference frames of the first B-Frames after GOP I-Frame
2896       are missing (open gop)*/
2897     broken_link = get_bits1(&s->gb);
2898
2899     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2900         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) broken_link=%d\n",
2901             time_code_hours, time_code_minutes, time_code_seconds,
2902             time_code_pictures, broken_link);
2903 }
2904 /**
2905  * finds the end of the current frame in the bitstream.
2906  * @return the position of the first byte of the next frame, or -1
2907  */
2908 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
2909 {
2910     int i;
2911     uint32_t state;
2912     
2913     state= pc->state;
2914     
2915     i=0;
2916     if(!pc->frame_start_found){
2917         for(i=0; i<buf_size; i++){
2918             state= (state<<8) | buf[i];
2919             if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2920                 i++;
2921                 pc->frame_start_found=1;
2922                 break;
2923             }
2924         }
2925     }
2926     
2927     if(pc->frame_start_found){
2928         /* EOF considered as end of frame */
2929         if (buf_size == 0)
2930             return 0;
2931         for(; i<buf_size; i++){
2932             state= (state<<8) | buf[i];
2933             if((state&0xFFFFFF00) == 0x100){
2934                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2935                     pc->frame_start_found=0;
2936                     pc->state=-1; 
2937                     return i-3;
2938                 }
2939             }
2940         }
2941     }        
2942     pc->state= state;
2943     return END_NOT_FOUND;
2944 }
2945
2946 /* handle buffering and image synchronisation */
2947 static int mpeg_decode_frame(AVCodecContext *avctx, 
2948                              void *data, int *data_size,
2949                              uint8_t *buf, int buf_size)
2950 {
2951     Mpeg1Context *s = avctx->priv_data;
2952     const uint8_t *buf_end;
2953     const uint8_t *buf_ptr;
2954     int ret, start_code, input_size;
2955     AVFrame *picture = data;
2956     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2957     dprintf("fill_buffer\n");
2958
2959     if (buf_size == 0) {
2960         /* special case for last picture */
2961         if (s2->low_delay==0 && s2->next_picture_ptr) {
2962             *picture= *(AVFrame*)s2->next_picture_ptr;
2963             s2->next_picture_ptr= NULL;
2964
2965             *data_size = sizeof(AVFrame);
2966         }
2967         return 0;
2968     }
2969
2970     if(s2->flags&CODEC_FLAG_TRUNCATED){
2971         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size);
2972         
2973         if( ff_combine_frame(&s2->parse_context, next, &buf, &buf_size) < 0 )
2974             return buf_size;
2975     }    
2976     
2977     buf_ptr = buf;
2978     buf_end = buf + buf_size;
2979
2980 #if 0    
2981     if (s->repeat_field % 2 == 1) { 
2982         s->repeat_field++;
2983         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2984         //        s2->picture_number, s->repeat_field);
2985         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2986             *data_size = sizeof(AVPicture);
2987             goto the_end;
2988         }
2989     }
2990 #endif
2991
2992     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == ff_get_fourcc("VCR2"))
2993         vcr2_init_sequence(avctx);
2994     
2995     s->slice_count= 0;
2996         
2997     for(;;) {
2998         /* find start next code */
2999         start_code = find_start_code(&buf_ptr, buf_end);
3000         if (start_code < 0){
3001             if(s2->pict_type != B_TYPE || avctx->hurry_up==0){
3002                 if(avctx->thread_count > 1){
3003                     int i;
3004
3005                     avctx->execute(avctx, slice_decode_thread,  (void**)&(s2->thread_context[0]), NULL, s->slice_count);
3006                     for(i=0; i<s->slice_count; i++)
3007                         s2->error_count += s2->thread_context[i]->error_count;
3008                 }
3009                 if (slice_end(avctx, picture)) {
3010                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
3011                         *data_size = sizeof(AVPicture);
3012                 }
3013             }
3014             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
3015         }
3016         
3017         input_size = buf_end - buf_ptr;
3018
3019         if(avctx->debug & FF_DEBUG_STARTCODE){
3020             av_log(avctx, AV_LOG_DEBUG, "%3X at %zd left %d\n", start_code, buf_ptr-buf, input_size);
3021         }
3022
3023                 /* prepare data for next start code */
3024                 switch(start_code) {
3025                 case SEQ_START_CODE:
3026                     mpeg1_decode_sequence(avctx, buf_ptr, 
3027                                           input_size);
3028                     break;
3029                             
3030                 case PICTURE_START_CODE:
3031                     /* we have a complete image : we try to decompress it */
3032                     mpeg1_decode_picture(avctx, 
3033                                          buf_ptr, input_size);
3034                     break;
3035                 case EXT_START_CODE:
3036                     mpeg_decode_extension(avctx,
3037                                           buf_ptr, input_size);
3038                     break;
3039                 case USER_START_CODE:
3040                     mpeg_decode_user_data(avctx, 
3041                                           buf_ptr, input_size);
3042                     break;
3043                 case GOP_START_CODE:
3044                     s2->first_field=0;
3045                     mpeg_decode_gop(avctx, 
3046                                           buf_ptr, input_size);
3047                     break;
3048                 default:
3049                     if (start_code >= SLICE_MIN_START_CODE &&
3050                         start_code <= SLICE_MAX_START_CODE) {
3051                         int mb_y= start_code - SLICE_MIN_START_CODE;
3052                         
3053                         /* skip b frames if we dont have reference frames */
3054                         if(s2->last_picture_ptr==NULL && s2->pict_type==B_TYPE) break;
3055                         /* skip b frames if we are in a hurry */
3056                         if(avctx->hurry_up && s2->pict_type==B_TYPE) break;
3057                         /* skip everything if we are in a hurry>=5 */
3058                         if(avctx->hurry_up>=5) break;
3059                         
3060                         if (!s->mpeg_enc_ctx_allocated) break;
3061
3062                         if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
3063                             if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
3064                                 break;
3065                         }
3066                         
3067                         if(s2->first_slice){
3068                             s2->first_slice=0;
3069                             if(mpeg_field_start(s2) < 0)
3070                                 return -1;
3071                         }
3072                         
3073                         if(avctx->thread_count > 1){
3074                             int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
3075                             if(threshold <= mb_y){
3076                                 MpegEncContext *thread_context= s2->thread_context[s->slice_count];
3077                                 
3078                                 thread_context->start_mb_y= mb_y;
3079                                 thread_context->end_mb_y  = s2->mb_height;
3080                                 if(s->slice_count){
3081                                     s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
3082                                     ff_update_duplicate_context(thread_context, s2);
3083                                 }
3084                                 init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
3085                                 s->slice_count++;
3086                             }
3087                             buf_ptr += 2; //FIXME add minimum num of bytes per slice
3088                         }else{
3089                             ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
3090                             emms_c();
3091
3092                             if(ret < 0){
3093                                 if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
3094                                     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);
3095                             }else{
3096                                 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);
3097                             }
3098                         }
3099                     }
3100                     break;
3101                 }
3102     }
3103 }
3104
3105 static int mpeg_decode_end(AVCodecContext *avctx)
3106 {
3107     Mpeg1Context *s = avctx->priv_data;
3108
3109     if (s->mpeg_enc_ctx_allocated)
3110         MPV_common_end(&s->mpeg_enc_ctx);
3111     return 0;
3112 }
3113
3114 AVCodec mpeg1video_decoder = {
3115     "mpeg1video",
3116     CODEC_TYPE_VIDEO,
3117     CODEC_ID_MPEG1VIDEO,
3118     sizeof(Mpeg1Context),
3119     mpeg_decode_init,
3120     NULL,
3121     mpeg_decode_end,
3122     mpeg_decode_frame,
3123     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
3124     .flush= ff_mpeg_flush,
3125 };
3126
3127 AVCodec mpeg2video_decoder = {
3128     "mpeg2video",
3129     CODEC_TYPE_VIDEO,
3130     CODEC_ID_MPEG2VIDEO,
3131     sizeof(Mpeg1Context),
3132     mpeg_decode_init,
3133     NULL,
3134     mpeg_decode_end,
3135     mpeg_decode_frame,
3136     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
3137     .flush= ff_mpeg_flush,
3138 };
3139
3140 //legacy decoder
3141 AVCodec mpegvideo_decoder = {
3142     "mpegvideo",
3143     CODEC_TYPE_VIDEO,
3144     CODEC_ID_MPEG2VIDEO,
3145     sizeof(Mpeg1Context),
3146     mpeg_decode_init,
3147     NULL,
3148     mpeg_decode_end,
3149     mpeg_decode_frame,
3150     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
3151     .flush= ff_mpeg_flush,
3152 };
3153
3154 #ifdef CONFIG_ENCODERS
3155
3156 AVCodec mpeg1video_encoder = {
3157     "mpeg1video",
3158     CODEC_TYPE_VIDEO,
3159     CODEC_ID_MPEG1VIDEO,
3160     sizeof(MpegEncContext),
3161     encode_init,
3162     MPV_encode_picture,
3163     MPV_encode_end,
3164     .supported_framerates= frame_rate_tab+1,
3165     .pix_fmts= (enum PixelFormat[]){PIX_FMT_YUV420P, -1},
3166     .capabilities= CODEC_CAP_DELAY,
3167 };
3168
3169 AVCodec mpeg2video_encoder = {
3170     "mpeg2video",
3171     CODEC_TYPE_VIDEO,
3172     CODEC_ID_MPEG2VIDEO,
3173     sizeof(MpegEncContext),
3174     encode_init,
3175     MPV_encode_picture,
3176     MPV_encode_end,
3177     .supported_framerates= frame_rate_tab+1,
3178     .pix_fmts= (enum PixelFormat[]){PIX_FMT_YUV420P, -1},
3179     .capabilities= CODEC_CAP_DELAY,
3180 };
3181 #endif
3182
3183 #ifdef HAVE_XVMC
3184 static int mpeg_mc_decode_init(AVCodecContext *avctx){
3185     Mpeg1Context *s;
3186
3187     if( avctx->thread_count > 1) 
3188         return -1;
3189     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
3190         return -1;
3191     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
3192         dprintf("mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
3193     }
3194     mpeg_decode_init(avctx);
3195     s = avctx->priv_data;
3196
3197     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
3198     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
3199
3200     return 0;
3201 }
3202
3203 AVCodec mpeg_xvmc_decoder = {
3204     "mpegvideo_xvmc",
3205     CODEC_TYPE_VIDEO,
3206     CODEC_ID_MPEG2VIDEO_XVMC,
3207     sizeof(Mpeg1Context),
3208     mpeg_mc_decode_init,
3209     NULL,
3210     mpeg_decode_end,
3211     mpeg_decode_frame,
3212     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
3213     .flush= ff_mpeg_flush,
3214 };
3215
3216 #endif
3217
3218 /* this is ugly i know, but the alternative is too make 
3219    hundreds of vars global and prefix them with ff_mpeg1_
3220    which is far uglier. */
3221 #include "mdec.c"