05023d4bc64cdf76c04f41f63a5c80a6ef687dd2
[ffmpeg.git] / libavcodec / mpeg12.c
1 /*
2  * MPEG1 codec / MPEG2 decoder
3  * Copyright (c) 2000,2001 Fabrice Bellard.
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with this library; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  */
19  
20 /**
21  * @file mpeg12.c
22  * MPEG1 codec / MPEG2 decoder.
23  */
24  
25 //#define DEBUG
26 #include "avcodec.h"
27 #include "dsputil.h"
28 #include "mpegvideo.h"
29
30 #include "mpeg12data.h"
31
32
33 /* Start codes. */
34 #define SEQ_END_CODE            0x000001b7
35 #define SEQ_START_CODE          0x000001b3
36 #define GOP_START_CODE          0x000001b8
37 #define PICTURE_START_CODE      0x00000100
38 #define SLICE_MIN_START_CODE    0x00000101
39 #define SLICE_MAX_START_CODE    0x000001af
40 #define EXT_START_CODE          0x000001b5
41 #define USER_START_CODE         0x000001b2
42
43 #define DC_VLC_BITS 9
44 #define MV_VLC_BITS 9
45 #define MBINCR_VLC_BITS 9
46 #define MB_PAT_VLC_BITS 9
47 #define MB_PTYPE_VLC_BITS 6
48 #define MB_BTYPE_VLC_BITS 6
49 #define TEX_VLC_BITS 9
50
51 static void mpeg1_encode_block(MpegEncContext *s, 
52                          DCTELEM *block, 
53                          int component);
54 static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code);    // RAL: f_code parameter added
55 static void mpeg1_skip_picture(MpegEncContext *s, int pict_num);
56 static inline int mpeg1_decode_block_inter(MpegEncContext *s, 
57                               DCTELEM *block, 
58                               int n);
59 static inline int mpeg1_decode_block_intra(MpegEncContext *s, 
60                               DCTELEM *block, 
61                               int n);
62 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, 
63                                         DCTELEM *block, 
64                                         int n);
65 static inline int mpeg2_decode_block_intra(MpegEncContext *s, 
66                                     DCTELEM *block, 
67                                     int n);
68 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
69
70 #ifdef CONFIG_ENCODERS
71 static uint8_t (*mv_penalty)[MAX_MV*2+1]= NULL;
72 static uint8_t fcode_tab[MAX_MV*2+1];
73
74 static uint32_t uni_mpeg1_ac_vlc_bits[64*64*2];
75 static uint8_t  uni_mpeg1_ac_vlc_len [64*64*2];
76 #endif
77
78 static void init_2d_vlc_rl(RLTable *rl)
79 {
80     int i;
81     
82     init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2, 
83              &rl->table_vlc[0][1], 4, 2,
84              &rl->table_vlc[0][0], 4, 2);
85
86     
87     rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
88     for(i=0; i<rl->vlc.table_size; i++){
89         int code= rl->vlc.table[i][0];
90         int len = rl->vlc.table[i][1];
91         int level, run;
92     
93         if(len==0){ // illegal code
94             run= 65;
95             level= MAX_LEVEL;
96         }else if(len<0){ //more bits needed
97             run= 0;
98             level= code;
99         }else{
100             if(code==rl->n){ //esc
101                 run= 65;
102                 level= 0;
103             }else if(code==rl->n+1){ //eob
104                 run= 0;
105                 level= 127;
106             }else{
107                 run=   rl->table_run  [code] + 1;
108                 level= rl->table_level[code];
109             }
110         }
111         rl->rl_vlc[0][i].len= len;
112         rl->rl_vlc[0][i].level= level;
113         rl->rl_vlc[0][i].run= run;
114     }
115 }
116
117 static void init_uni_ac_vlc(RLTable *rl, uint32_t *uni_ac_vlc_bits, uint8_t *uni_ac_vlc_len){
118     int i;
119
120     for(i=0; i<128; i++){
121         int level= i-64;
122         int run;
123         for(run=0; run<64; run++){
124             int len, bits, code;
125             
126             int alevel= ABS(level);
127             int sign= (level>>31)&1;
128
129             if (alevel > rl->max_level[0][run])
130                 code= 111; /*rl->n*/
131             else
132                 code= rl->index_run[0][run] + alevel - 1;
133
134             if (code < 111 /* rl->n */) {
135                 /* store the vlc & sign at once */
136                 len=   mpeg1_vlc[code][1]+1;
137                 bits= (mpeg1_vlc[code][0]<<1) + sign;
138             } else {
139                 len=  mpeg1_vlc[111/*rl->n*/][1]+6;
140                 bits= mpeg1_vlc[111/*rl->n*/][0]<<6;
141
142                 bits|= run;
143                 if (alevel < 128) {
144                     bits<<=8; len+=8;
145                     bits|= level & 0xff;
146                 } else {
147                     bits<<=16; len+=16;
148                     bits|= level & 0xff;
149                     if (level < 0) {
150                         bits|= 0x8001 + level + 255;
151                     } else {
152                         bits|= level & 0xffff;
153                     }
154                 }
155             }
156
157             uni_ac_vlc_bits[UNI_AC_ENC_INDEX(run, i)]= bits;
158             uni_ac_vlc_len [UNI_AC_ENC_INDEX(run, i)]= len;
159         }
160     }
161 }
162
163 static void put_header(MpegEncContext *s, int header)
164 {
165     align_put_bits(&s->pb);
166     put_bits(&s->pb, 16, header>>16);
167     put_bits(&s->pb, 16, header&0xFFFF);
168 }
169
170 /* put sequence header if needed */
171 static void mpeg1_encode_sequence_header(MpegEncContext *s)
172 {
173         unsigned int vbv_buffer_size;
174         unsigned int fps, v;
175         int n, i;
176         uint64_t time_code;
177         float best_aspect_error= 1E10;
178         float aspect_ratio= s->avctx->aspect_ratio;
179         
180         if(aspect_ratio==0.0) aspect_ratio= s->width / (float)s->height; //pixel aspect 1:1 (VGA)
181         
182         if (s->current_picture.key_frame) {
183             /* mpeg1 header repeated every gop */
184             put_header(s, SEQ_START_CODE);
185             
186             /* search closest frame rate */
187             {
188                 int i, dmin, d;
189                 s->frame_rate_index = 0;
190                 dmin = 0x7fffffff;
191                 for(i=1;i<14;i++) {
192                     if(s->avctx->strict_std_compliance >= 0 && i>=9) break;
193                      
194                     d = abs(MPEG1_FRAME_RATE_BASE*(int64_t)s->avctx->frame_rate/s->avctx->frame_rate_base - frame_rate_tab[i]);
195                     if (d < dmin) {
196                         dmin = d;
197                         s->frame_rate_index = i;
198                     }
199                 }
200             }
201  
202             put_bits(&s->pb, 12, s->width);
203             put_bits(&s->pb, 12, s->height);
204             
205             for(i=1; i<15; i++){
206                 float error= mpeg1_aspect[i] - s->width/(s->height*aspect_ratio);
207                 error= ABS(error);
208                 
209                 if(error < best_aspect_error){
210                     best_aspect_error= error;
211                     s->aspect_ratio_info= i;
212                 }
213             }
214             
215             put_bits(&s->pb, 4, s->aspect_ratio_info);
216             put_bits(&s->pb, 4, s->frame_rate_index);
217             v = (s->bit_rate + 399) / 400;
218             if (v > 0x3ffff)
219                 v = 0x3ffff;
220             put_bits(&s->pb, 18, v);
221             put_bits(&s->pb, 1, 1); /* marker */
222
223             if(s->avctx->rc_buffer_size)
224                 vbv_buffer_size = s->avctx->rc_buffer_size;
225             else
226                 /* VBV calculation: Scaled so that a VCD has the proper VBV size of 40 kilobytes */
227                 vbv_buffer_size = (( 20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024;      
228             put_bits(&s->pb, 10, (vbv_buffer_size + 16383) / 16384); 
229             put_bits(&s->pb, 1, 1); /* constrained parameter flag */
230             put_bits(&s->pb, 1, 0); /* no custom intra matrix */
231             put_bits(&s->pb, 1, 0); /* no custom non intra matrix */
232
233             put_header(s, GOP_START_CODE);
234             put_bits(&s->pb, 1, 0); /* do drop frame */
235             /* time code : we must convert from the real frame rate to a
236                fake mpeg frame rate in case of low frame rate */
237             fps = frame_rate_tab[s->frame_rate_index];
238             time_code = (int64_t)s->fake_picture_number * MPEG1_FRAME_RATE_BASE;
239             s->gop_picture_number = s->fake_picture_number;
240             put_bits(&s->pb, 5, (uint32_t)((time_code / (fps * 3600)) % 24));
241             put_bits(&s->pb, 6, (uint32_t)((time_code / (fps * 60)) % 60));
242             put_bits(&s->pb, 1, 1);
243             put_bits(&s->pb, 6, (uint32_t)((time_code / fps) % 60));
244             put_bits(&s->pb, 6, (uint32_t)((time_code % fps) / MPEG1_FRAME_RATE_BASE));
245             put_bits(&s->pb, 1, 1); /* closed gop */
246             put_bits(&s->pb, 1, 0); /* broken link */
247         }
248
249         if (s->avctx->frame_rate < (24 * s->avctx->frame_rate_base) && s->picture_number > 0) {
250             /* insert empty P pictures to slow down to the desired
251                frame rate. Each fake pictures takes about 20 bytes */
252             fps = frame_rate_tab[s->frame_rate_index];
253             n = av_rescale((int64_t)s->picture_number * s->avctx->frame_rate_base, fps, s->avctx->frame_rate) / MPEG1_FRAME_RATE_BASE - 1;
254             while (s->fake_picture_number < n) {
255                 mpeg1_skip_picture(s, s->fake_picture_number - 
256                                    s->gop_picture_number); 
257                 s->fake_picture_number++;
258             }
259
260         }
261 }
262
263 static inline void encode_mb_skip_run(MpegEncContext *s, int run){
264     while (run >= 33) {
265         put_bits(&s->pb, 11, 0x008);
266         run -= 33;
267     }
268     put_bits(&s->pb, mbAddrIncrTable[run][1], 
269              mbAddrIncrTable[run][0]);
270 }
271
272 /* insert a fake P picture */
273 static void mpeg1_skip_picture(MpegEncContext *s, int pict_num)
274 {
275     /* mpeg1 picture header */
276     put_header(s, PICTURE_START_CODE);
277     /* temporal reference */
278     put_bits(&s->pb, 10, pict_num & 0x3ff); 
279     
280     put_bits(&s->pb, 3, P_TYPE);
281     put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
282     
283     put_bits(&s->pb, 1, 1); /* integer coordinates */
284     put_bits(&s->pb, 3, 1); /* forward_f_code */
285     
286     put_bits(&s->pb, 1, 0); /* extra bit picture */
287     
288     /* only one slice */
289     put_header(s, SLICE_MIN_START_CODE);
290     put_bits(&s->pb, 5, 1); /* quantizer scale */
291     put_bits(&s->pb, 1, 0); /* slice extra information */
292     
293     encode_mb_skip_run(s, 0);
294     
295     /* empty macroblock */
296     put_bits(&s->pb, 3, 1); /* motion only */
297     
298     /* zero motion x & y */
299     put_bits(&s->pb, 1, 1); 
300     put_bits(&s->pb, 1, 1); 
301
302     /* output a number of empty slice */
303     encode_mb_skip_run(s, s->mb_width * s->mb_height - 2);
304     
305     /* empty macroblock */
306     put_bits(&s->pb, 3, 1); /* motion only */
307     
308     /* zero motion x & y */
309     put_bits(&s->pb, 1, 1); 
310     put_bits(&s->pb, 1, 1); 
311 }
312
313 static void common_init(MpegEncContext *s)
314 {
315     s->y_dc_scale_table=
316     s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
317 }
318
319 #ifdef CONFIG_ENCODERS
320
321 void ff_mpeg1_encode_slice_header(MpegEncContext *s){
322     put_header(s, SLICE_MIN_START_CODE + s->mb_y);
323     put_bits(&s->pb, 5, s->qscale); /* quantizer scale */
324     put_bits(&s->pb, 1, 0); /* slice extra information */
325 }
326
327 void ff_mpeg1_clean_buffers(MpegEncContext *s){
328     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
329     s->last_dc[1] = s->last_dc[0];
330     s->last_dc[2] = s->last_dc[0];
331     memset(s->last_mv, 0, sizeof(s->last_mv));
332 }
333
334 void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
335 {
336     mpeg1_encode_sequence_header(s);
337
338     /* mpeg1 picture header */
339     put_header(s, PICTURE_START_CODE);
340     /* temporal reference */
341
342     // RAL: s->picture_number instead of s->fake_picture_number
343     put_bits(&s->pb, 10, (s->picture_number - 
344                           s->gop_picture_number) & 0x3ff); 
345     s->fake_picture_number++;
346     
347     put_bits(&s->pb, 3, s->pict_type);
348     put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
349     
350     // RAL: Forward f_code also needed for B frames
351     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
352         put_bits(&s->pb, 1, 0); /* half pel coordinates */
353         put_bits(&s->pb, 3, s->f_code); /* forward_f_code */
354     }
355     
356     // RAL: Backward f_code necessary for B frames
357     if (s->pict_type == B_TYPE) {
358         put_bits(&s->pb, 1, 0); /* half pel coordinates */
359         put_bits(&s->pb, 3, s->b_code); /* backward_f_code */
360         }
361
362     put_bits(&s->pb, 1, 0); /* extra bit picture */
363     
364     s->mb_y=0;
365     ff_mpeg1_encode_slice_header(s);
366 }
367
368 void mpeg1_encode_mb(MpegEncContext *s,
369                      DCTELEM block[6][64],
370                      int motion_x, int motion_y)
371 {
372     int i, cbp;
373     const int mb_x = s->mb_x;
374     const int mb_y = s->mb_y;
375     const int first_mb= mb_x == s->resync_mb_x && mb_y == s->resync_mb_y;
376
377     /* compute cbp */
378     cbp = 0;
379     for(i=0;i<6;i++) {
380         if (s->block_last_index[i] >= 0)
381             cbp |= 1 << (5 - i);
382     }
383
384     if (cbp == 0 && !first_mb && (mb_x != s->mb_width - 1 || mb_y != s->mb_height - 1) && 
385         ((s->pict_type == P_TYPE && (motion_x | motion_y) == 0) ||
386         (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) |
387         ((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))) {
388         s->mb_skip_run++;
389         s->qscale -= s->dquant;
390         s->skip_count++;
391         s->misc_bits++;
392         s->last_bits++;
393     } else {
394         if(first_mb){
395             assert(s->mb_skip_run == 0);
396             encode_mb_skip_run(s, s->mb_x);
397         }else{
398             encode_mb_skip_run(s, s->mb_skip_run);
399         }
400         
401         if (s->pict_type == I_TYPE) {
402             if(s->dquant && cbp){
403                 put_bits(&s->pb, 2, 1); /* macroblock_type : macroblock_quant = 1 */
404                 put_bits(&s->pb, 5, s->qscale);
405             }else{
406                 put_bits(&s->pb, 1, 1); /* macroblock_type : macroblock_quant = 0 */
407                 s->qscale -= s->dquant;
408             }
409             s->misc_bits+= get_bits_diff(s);
410             s->i_count++;
411         } else if (s->mb_intra) {
412             if(s->dquant && cbp){
413                 put_bits(&s->pb, 6, 0x01);
414                 put_bits(&s->pb, 5, s->qscale);
415             }else{
416                 put_bits(&s->pb, 5, 0x03);
417                 s->qscale -= s->dquant;
418             }
419             s->misc_bits+= get_bits_diff(s);
420             s->i_count++;
421             s->last_mv[0][0][0] = 
422             s->last_mv[0][0][1] = 0;
423         } else if (s->pict_type == P_TYPE) { 
424                 if (cbp != 0) {
425                     if (motion_x == 0 && motion_y == 0) {
426                         if(s->dquant){
427                             put_bits(&s->pb, 5, 1); /* macroblock_pattern & quant */
428                             put_bits(&s->pb, 5, s->qscale);
429                         }else{
430                             put_bits(&s->pb, 2, 1); /* macroblock_pattern only */
431                         }
432                         s->misc_bits+= get_bits_diff(s);
433                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
434                     } else {
435                         if(s->dquant){
436                             put_bits(&s->pb, 5, 2); /* motion + cbp */
437                             put_bits(&s->pb, 5, s->qscale);
438                         }else{
439                             put_bits(&s->pb, 1, 1); /* motion + cbp */
440                         }
441                         s->misc_bits+= get_bits_diff(s);
442                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
443                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
444                         s->mv_bits+= get_bits_diff(s);
445                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
446                     }
447                 } else {
448                     put_bits(&s->pb, 3, 1); /* motion only */
449                     mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
450                     mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
451                     s->qscale -= s->dquant;
452                     s->mv_bits+= get_bits_diff(s);
453                 }
454                 s->f_count++;
455         } else
456             {    // RAL: All the following bloc added for B frames:
457                 if (cbp != 0)
458                     {    // With coded bloc pattern
459                     if (s->mv_dir == (MV_DIR_FORWARD | MV_DIR_BACKWARD))
460                         {    // Bi-directional motion
461                         if (s->dquant)
462                             {    // With QScale
463                             put_bits(&s->pb, 5, 2);
464                             put_bits(&s->pb, 5, s->qscale);
465                             }
466                         else    // Without QScale
467                             put_bits(&s->pb, 2, 3);
468                         s->misc_bits += get_bits_diff(s);
469                         mpeg1_encode_motion(s, s->mv[0][0][0] - s->last_mv[0][0][0], s->f_code);
470                         mpeg1_encode_motion(s, s->mv[0][0][1] - s->last_mv[0][0][1], s->f_code);
471                         mpeg1_encode_motion(s, s->mv[1][0][0] - s->last_mv[1][0][0], s->b_code);
472                         mpeg1_encode_motion(s, s->mv[1][0][1] - s->last_mv[1][0][1], s->b_code);
473                         s->b_count++;
474                         s->f_count++;
475                         s->mv_bits += get_bits_diff(s);
476                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
477                         }
478                     else if (s->mv_dir == MV_DIR_BACKWARD)
479                         {    // Backward motion
480                         if (s->dquant)
481                             {    // With QScale
482                             put_bits(&s->pb, 6, 2);
483                             put_bits(&s->pb, 5, s->qscale);
484                             }
485                         else    // Without QScale
486                             put_bits(&s->pb, 3, 3);
487                         s->misc_bits += get_bits_diff(s);
488                         mpeg1_encode_motion(s, motion_x - s->last_mv[1][0][0], s->b_code); 
489                         mpeg1_encode_motion(s, motion_y - s->last_mv[1][0][1], s->b_code); 
490                         s->b_count++;
491                         s->mv_bits += get_bits_diff(s);
492                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
493                         }
494                     else if (s->mv_dir == MV_DIR_FORWARD)
495                         {    // Forward motion
496                         if (s->dquant)
497                             {    // With QScale
498                             put_bits(&s->pb, 6, 3);
499                             put_bits(&s->pb, 5, s->qscale);
500                             }
501                         else    // Without QScale
502                             put_bits(&s->pb, 4, 3);
503                         s->misc_bits += get_bits_diff(s);
504                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code); 
505                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code); 
506                         s->f_count++;
507                         s->mv_bits += get_bits_diff(s);
508                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
509                         }
510                     }
511                 else
512                     {    // No coded bloc pattern
513                     if (s->mv_dir == (MV_DIR_FORWARD | MV_DIR_BACKWARD))
514                         {    // Bi-directional motion 
515                         put_bits(&s->pb, 2, 2); /* backward & forward motion */
516                         mpeg1_encode_motion(s, s->mv[0][0][0] - s->last_mv[0][0][0], s->f_code);
517                         mpeg1_encode_motion(s, s->mv[0][0][1] - s->last_mv[0][0][1], s->f_code);
518                         mpeg1_encode_motion(s, s->mv[1][0][0] - s->last_mv[1][0][0], s->b_code);
519                         mpeg1_encode_motion(s, s->mv[1][0][1] - s->last_mv[1][0][1], s->b_code);
520                         s->b_count++;
521                         s->f_count++;
522                         }
523                     else if (s->mv_dir == MV_DIR_BACKWARD)
524                         {    // Backward motion
525                         put_bits(&s->pb, 3, 2); /* backward motion only */
526                         mpeg1_encode_motion(s, motion_x - s->last_mv[1][0][0], s->b_code); 
527                         mpeg1_encode_motion(s, motion_y - s->last_mv[1][0][1], s->b_code); 
528                         s->b_count++;
529                         }
530                     else if (s->mv_dir == MV_DIR_FORWARD)
531                         {    // Forward motion
532                         put_bits(&s->pb, 4, 2); /* forward motion only */
533                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code); 
534                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code); 
535                         s->f_count++;
536                         }
537                     s->qscale -= s->dquant;
538                     s->mv_bits += get_bits_diff(s);
539                     }
540             // End of bloc from RAL
541             }
542         for(i=0;i<6;i++) {
543             if (cbp & (1 << (5 - i))) {
544                 mpeg1_encode_block(s, block[i], i);
545             }
546         }
547         s->mb_skip_run = 0;
548         if(s->mb_intra)
549             s->i_tex_bits+= get_bits_diff(s);
550         else
551             s->p_tex_bits+= get_bits_diff(s);
552     }
553
554     // RAL: By this:
555     if (s->mv_dir & MV_DIR_FORWARD)
556         {
557         s->last_mv[0][0][0]= s->mv[0][0][0];
558         s->last_mv[0][0][1]= s->mv[0][0][1];
559         }
560     if (s->mv_dir & MV_DIR_BACKWARD)
561         {
562         s->last_mv[1][0][0]= s->mv[1][0][0];
563         s->last_mv[1][0][1]= s->mv[1][0][1];
564         }
565 }
566
567 // RAL: Parameter added: f_or_b_code
568 static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code)
569 {
570     int code, bit_size, l, m, bits, range, sign;
571
572     if (val == 0) {
573         /* zero vector */
574         code = 0;
575         put_bits(&s->pb,
576                  mbMotionVectorTable[0][1], 
577                  mbMotionVectorTable[0][0]); 
578     } else {
579         bit_size = f_or_b_code - 1;
580         range = 1 << bit_size;
581         /* modulo encoding */
582         l = 16 * range;
583         m = 2 * l;
584         if (val < -l) {
585             val += m;
586         } else if (val >= l) {
587             val -= m;
588         }
589
590         if (val >= 0) {
591             val--;
592             code = (val >> bit_size) + 1;
593             bits = val & (range - 1);
594             sign = 0;
595         } else {
596             val = -val;
597             val--;
598             code = (val >> bit_size) + 1;
599             bits = val & (range - 1);
600             sign = 1;
601         }
602
603         assert(code > 0 && code <= 16);
604
605         put_bits(&s->pb,
606                  mbMotionVectorTable[code][1], 
607                  mbMotionVectorTable[code][0]); 
608
609         put_bits(&s->pb, 1, sign);
610         if (bit_size > 0) {
611             put_bits(&s->pb, bit_size, bits);
612         }
613     }
614 }
615
616 void ff_mpeg1_encode_init(MpegEncContext *s)
617 {
618     static int done=0;
619
620     common_init(s);
621
622     if(!done){
623         int f_code;
624         int mv;
625         int i;
626
627         done=1;
628         init_rl(&rl_mpeg1);
629
630         for(i=0; i<64; i++)
631         {
632                 mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i];
633                 mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i];
634         }
635         
636         init_uni_ac_vlc(&rl_mpeg1, uni_mpeg1_ac_vlc_bits, uni_mpeg1_ac_vlc_len);
637
638         /* build unified dc encoding tables */
639         for(i=-255; i<256; i++)
640         {
641                 int adiff, index;
642                 int bits, code;
643                 int diff=i;
644
645                 adiff = ABS(diff);
646                 if(diff<0) diff--;
647                 index = vlc_dc_table[adiff];
648
649                 bits= vlc_dc_lum_bits[index] + index;
650                 code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1));
651                 mpeg1_lum_dc_uni[i+255]= bits + (code<<8);
652                 
653                 bits= vlc_dc_chroma_bits[index] + index;
654                 code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1));
655                 mpeg1_chr_dc_uni[i+255]= bits + (code<<8);
656         }
657
658         mv_penalty= av_mallocz( sizeof(uint8_t)*(MAX_FCODE+1)*(2*MAX_MV+1) );
659
660         for(f_code=1; f_code<=MAX_FCODE; f_code++){
661             for(mv=-MAX_MV; mv<=MAX_MV; mv++){
662                 int len;
663
664                 if(mv==0) len= mbMotionVectorTable[0][1];
665                 else{
666                     int val, bit_size, range, code;
667
668                     bit_size = s->f_code - 1;
669                     range = 1 << bit_size;
670
671                     val=mv;
672                     if (val < 0) 
673                         val = -val;
674                     val--;
675                     code = (val >> bit_size) + 1;
676                     if(code<17){
677                         len= mbMotionVectorTable[code][1] + 1 + bit_size;
678                     }else{
679                         len= mbMotionVectorTable[16][1] + 2 + bit_size;
680                     }
681                 }
682
683                 mv_penalty[f_code][mv+MAX_MV]= len;
684             }
685         }
686         
687
688         for(f_code=MAX_FCODE; f_code>0; f_code--){
689             for(mv=-(8<<f_code); mv<(8<<f_code); mv++){
690                 fcode_tab[mv+MAX_MV]= f_code;
691             }
692         }
693     }
694     s->me.mv_penalty= mv_penalty;
695     s->fcode_tab= fcode_tab;
696     s->min_qcoeff=-255;
697     s->max_qcoeff= 255;
698     s->intra_ac_vlc_length=
699     s->inter_ac_vlc_length= uni_mpeg1_ac_vlc_len;
700 }
701
702 static inline void encode_dc(MpegEncContext *s, int diff, int component)
703 {
704     if (component == 0) {
705         put_bits(
706             &s->pb, 
707             mpeg1_lum_dc_uni[diff+255]&0xFF,
708             mpeg1_lum_dc_uni[diff+255]>>8);
709     } else {
710         put_bits(
711             &s->pb, 
712             mpeg1_chr_dc_uni[diff+255]&0xFF,
713             mpeg1_chr_dc_uni[diff+255]>>8);
714     }
715 }
716
717 static void mpeg1_encode_block(MpegEncContext *s, 
718                                DCTELEM *block, 
719                                int n)
720 {
721     int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign;
722     int code, component;
723 //    RLTable *rl = &rl_mpeg1;
724
725     last_index = s->block_last_index[n];
726
727     /* DC coef */
728     if (s->mb_intra) {
729         component = (n <= 3 ? 0 : n - 4 + 1);
730         dc = block[0]; /* overflow is impossible */
731         diff = dc - s->last_dc[component];
732         encode_dc(s, diff, component);
733         s->last_dc[component] = dc;
734         i = 1;
735     } else {
736         /* encode the first coefficient : needs to be done here because
737            it is handled slightly differently */
738         level = block[0];
739         if (abs(level) == 1) {
740                 code = ((uint32_t)level >> 31); /* the sign bit */
741                 put_bits(&s->pb, 2, code | 0x02);
742                 i = 1;
743         } else {
744             i = 0;
745             last_non_zero = -1;
746             goto next_coef;
747         }
748     }
749
750     /* now quantify & encode AC coefs */
751     last_non_zero = i - 1;
752
753     for(;i<=last_index;i++) {
754         j = s->intra_scantable.permutated[i];
755         level = block[j];
756     next_coef:
757 #if 0
758         if (level != 0)
759             dprintf("level[%d]=%d\n", i, level);
760 #endif            
761         /* encode using VLC */
762         if (level != 0) {
763             run = i - last_non_zero - 1;
764             
765             alevel= level;
766             MASK_ABS(sign, alevel)
767             sign&=1;
768
769 //            code = get_rl_index(rl, 0, run, alevel);
770             if (alevel <= mpeg1_max_level[0][run]){
771                 code= mpeg1_index_run[0][run] + alevel - 1;
772                 /* store the vlc & sign at once */
773                 put_bits(&s->pb, mpeg1_vlc[code][1]+1, (mpeg1_vlc[code][0]<<1) + sign);
774             } else {
775                 /* escape seems to be pretty rare <5% so i dont optimize it */
776                 put_bits(&s->pb, mpeg1_vlc[111/*rl->n*/][1], mpeg1_vlc[111/*rl->n*/][0]);
777                 /* escape: only clip in this case */
778                 put_bits(&s->pb, 6, run);
779                 if (alevel < 128) {
780                     put_bits(&s->pb, 8, level & 0xff);
781                 } else {
782                     if (level < 0) {
783                         put_bits(&s->pb, 16, 0x8001 + level + 255);
784                     } else {
785                         put_bits(&s->pb, 16, level & 0xffff);
786                     }
787                 }
788             }
789             last_non_zero = i;
790         }
791     }
792     /* end of block */
793     put_bits(&s->pb, 2, 0x2);
794 }
795 #endif //CONFIG_ENCODERS
796
797 /******************************************/
798 /* decoding */
799
800 static VLC dc_lum_vlc;
801 static VLC dc_chroma_vlc;
802 static VLC mv_vlc;
803 static VLC mbincr_vlc;
804 static VLC mb_ptype_vlc;
805 static VLC mb_btype_vlc;
806 static VLC mb_pat_vlc;
807
808 static void init_vlcs(MpegEncContext *s)
809 {
810     static int done = 0;
811
812     if (!done) {
813         done = 1;
814
815         init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12, 
816                  vlc_dc_lum_bits, 1, 1,
817                  vlc_dc_lum_code, 2, 2);
818         init_vlc(&dc_chroma_vlc,  DC_VLC_BITS, 12, 
819                  vlc_dc_chroma_bits, 1, 1,
820                  vlc_dc_chroma_code, 2, 2);
821         init_vlc(&mv_vlc, MV_VLC_BITS, 17, 
822                  &mbMotionVectorTable[0][1], 2, 1,
823                  &mbMotionVectorTable[0][0], 2, 1);
824         init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36, 
825                  &mbAddrIncrTable[0][1], 2, 1,
826                  &mbAddrIncrTable[0][0], 2, 1);
827         init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 63, 
828                  &mbPatTable[0][1], 2, 1,
829                  &mbPatTable[0][0], 2, 1);
830         
831         init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7, 
832                  &table_mb_ptype[0][1], 2, 1,
833                  &table_mb_ptype[0][0], 2, 1);
834         init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11, 
835                  &table_mb_btype[0][1], 2, 1,
836                  &table_mb_btype[0][0], 2, 1);
837         init_rl(&rl_mpeg1);
838         init_rl(&rl_mpeg2);
839
840         init_2d_vlc_rl(&rl_mpeg1);
841         init_2d_vlc_rl(&rl_mpeg2);
842     }
843 }
844
845 static inline int get_dmv(MpegEncContext *s)
846 {
847     if(get_bits1(&s->gb)) 
848         return 1 - (get_bits1(&s->gb) << 1);
849     else
850         return 0;
851 }
852
853 static inline int get_qscale(MpegEncContext *s)
854 {
855     int qscale = get_bits(&s->gb, 5);
856     if (s->mpeg2) {
857         if (s->q_scale_type) {
858             return non_linear_qscale[qscale];
859         } else {
860             return qscale << 1;
861         }
862     }
863     return qscale;
864 }
865
866 /* motion type (for mpeg2) */
867 #define MT_FIELD 1
868 #define MT_FRAME 2
869 #define MT_16X8  2
870 #define MT_DMV   3
871
872 static int mpeg_decode_mb(MpegEncContext *s,
873                           DCTELEM block[6][64])
874 {
875     int i, j, k, cbp, val, mb_type, motion_type;
876     
877     dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
878
879     assert(s->mb_skiped==0);
880
881     if (s->mb_skip_run-- != 0) {
882         if(s->pict_type == I_TYPE){
883             fprintf(stderr, "skiped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
884             return -1;
885         }
886     
887         /* skip mb */
888         s->mb_intra = 0;
889         for(i=0;i<6;i++)
890             s->block_last_index[i] = -1;
891         s->mv_type = MV_TYPE_16X16;
892         if (s->pict_type == P_TYPE) {
893             /* if P type, zero motion vector is implied */
894             s->mv_dir = MV_DIR_FORWARD;
895             s->mv[0][0][0] = s->mv[0][0][1] = 0;
896             s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
897             s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
898             s->mb_skiped = 1;
899             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
900         } else {
901             /* if B type, reuse previous vectors and directions */
902             s->mv[0][0][0] = s->last_mv[0][0][0];
903             s->mv[0][0][1] = s->last_mv[0][0][1];
904             s->mv[1][0][0] = s->last_mv[1][0][0];
905             s->mv[1][0][1] = s->last_mv[1][0][1];
906
907             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= 
908                 s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1] | MB_TYPE_SKIP;
909 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
910
911             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0) 
912                 s->mb_skiped = 1;
913         }
914
915         return 0;
916     }
917
918     switch(s->pict_type) {
919     default:
920     case I_TYPE:
921         if (get_bits1(&s->gb) == 0) {
922             if (get_bits1(&s->gb) == 0)
923                 return -1;
924             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
925         } else {
926             mb_type = MB_TYPE_INTRA;
927         }
928         break;
929     case P_TYPE:
930         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
931         if (mb_type < 0){
932             fprintf(stderr, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
933             return -1;
934         }
935         mb_type = ptype2mb_type[ mb_type ];
936         break;
937     case B_TYPE:
938         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
939         if (mb_type < 0){
940             fprintf(stderr, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
941             return -1;
942         }
943         mb_type = btype2mb_type[ mb_type ];
944         break;
945     }
946     dprintf("mb_type=%x\n", mb_type);
947 //    motion_type = 0; /* avoid warning */
948     if (IS_INTRA(mb_type)) {
949         /* compute dct type */
950         if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
951             !s->frame_pred_frame_dct) {
952             s->interlaced_dct = get_bits1(&s->gb);
953         }
954
955         if (IS_QUANT(mb_type))
956             s->qscale = get_qscale(s);
957         
958         if (s->concealment_motion_vectors) {
959             /* just parse them */
960             if (s->picture_structure != PICT_FRAME) 
961                 skip_bits1(&s->gb); /* field select */
962             
963             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] = 
964                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
965             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] = 
966                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
967
968             skip_bits1(&s->gb); /* marker */
969         }else
970             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
971         s->mb_intra = 1;
972
973         if (s->mpeg2) {
974             for(i=0;i<6;i++) {
975                 if (mpeg2_decode_block_intra(s, block[i], i) < 0)
976                     return -1;
977             }
978         } else {
979             for(i=0;i<6;i++) {
980                 if (mpeg1_decode_block_intra(s, block[i], i) < 0)
981                     return -1;
982             }
983         }
984     } else {
985         if (mb_type & MB_TYPE_ZERO_MV){
986             assert(mb_type & MB_TYPE_PAT);
987
988             /* compute dct type */
989             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
990                 !s->frame_pred_frame_dct) {
991                 s->interlaced_dct = get_bits1(&s->gb);
992             }
993
994             if (IS_QUANT(mb_type))
995                 s->qscale = get_qscale(s);
996
997             s->mv_dir = MV_DIR_FORWARD;
998             s->mv_type = MV_TYPE_16X16;
999             s->last_mv[0][0][0] = 0;
1000             s->last_mv[0][0][1] = 0;
1001             s->last_mv[0][1][0] = 0;
1002             s->last_mv[0][1][1] = 0;
1003             s->mv[0][0][0] = 0;
1004             s->mv[0][0][1] = 0;
1005         }else{
1006             assert(mb_type & MB_TYPE_L0L1);
1007 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
1008             /* get additionnal motion vector type */
1009             if (s->frame_pred_frame_dct) 
1010                 motion_type = MT_FRAME;
1011             else{
1012                 motion_type = get_bits(&s->gb, 2);
1013             }
1014
1015             /* compute dct type */
1016             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1017                 !s->frame_pred_frame_dct && IS_PAT(mb_type)) {
1018                 s->interlaced_dct = get_bits1(&s->gb);
1019             }
1020
1021             if (IS_QUANT(mb_type))
1022                 s->qscale = get_qscale(s);
1023
1024             /* motion vectors */
1025             s->mv_dir = 0;
1026             for(i=0;i<2;i++) {
1027                 if (USES_LIST(mb_type, i)) {
1028                     s->mv_dir |= (MV_DIR_FORWARD >> i);
1029                     dprintf("motion_type=%d\n", motion_type);
1030                     switch(motion_type) {
1031                     case MT_FRAME: /* or MT_16X8 */
1032                         if (s->picture_structure == PICT_FRAME) {
1033                             /* MT_FRAME */
1034                             mb_type |= MB_TYPE_16x16; 
1035                             s->mv_type = MV_TYPE_16X16;
1036                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] = 
1037                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
1038                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] = 
1039                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
1040                             /* full_pel: only for mpeg1 */
1041                             if (s->full_pel[i]){
1042                                 s->mv[i][0][0] <<= 1;
1043                                 s->mv[i][0][1] <<= 1;
1044                             }
1045                         } else {
1046                             /* MT_16X8 */
1047                             mb_type |= MB_TYPE_16x8; 
1048                             s->mv_type = MV_TYPE_16X8;
1049                             for(j=0;j<2;j++) {
1050                                 s->field_select[i][j] = get_bits1(&s->gb);
1051                                 for(k=0;k<2;k++) {
1052                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1053                                                              s->last_mv[i][j][k]);
1054                                     s->last_mv[i][j][k] = val;
1055                                     s->mv[i][j][k] = val;
1056                                 }
1057                             }
1058                         }
1059                         break;
1060                     case MT_FIELD:
1061                         s->mv_type = MV_TYPE_FIELD;
1062                         if (s->picture_structure == PICT_FRAME) {
1063                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED; 
1064                             for(j=0;j<2;j++) {
1065                                 s->field_select[i][j] = get_bits1(&s->gb);
1066                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1067                                                          s->last_mv[i][j][0]);
1068                                 s->last_mv[i][j][0] = val;
1069                                 s->mv[i][j][0] = val;
1070                                 dprintf("fmx=%d\n", val);
1071                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1072                                                          s->last_mv[i][j][1] >> 1);
1073                                 s->last_mv[i][j][1] = val << 1;
1074                                 s->mv[i][j][1] = val;
1075                                 dprintf("fmy=%d\n", val);
1076                             }
1077                         } else {
1078                             mb_type |= MB_TYPE_16x16; 
1079                             s->field_select[i][0] = get_bits1(&s->gb);
1080                             for(k=0;k<2;k++) {
1081                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1082                                                          s->last_mv[i][0][k]);
1083                                 s->last_mv[i][0][k] = val;
1084                                 s->last_mv[i][1][k] = val;
1085                                 s->mv[i][0][k] = val;
1086                             }
1087                         }
1088                         break;
1089                     case MT_DMV:
1090                         {
1091                             int dmx, dmy, mx, my, m;
1092
1093                             mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0], 
1094                                                     s->last_mv[i][0][0]);
1095                             s->last_mv[i][0][0] = mx;
1096                             s->last_mv[i][1][0] = mx;
1097                             dmx = get_dmv(s);
1098                             my = mpeg_decode_motion(s, s->mpeg_f_code[i][1], 
1099                                                     s->last_mv[i][0][1] >> 1);
1100                             dmy = get_dmv(s);
1101                             s->mv_type = MV_TYPE_DMV;
1102                             /* XXX: totally broken */
1103                             if (s->picture_structure == PICT_FRAME) {
1104                                 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED; 
1105
1106                                 s->last_mv[i][0][1] = my << 1;
1107                                 s->last_mv[i][1][1] = my << 1;
1108
1109                                 m = s->top_field_first ? 1 : 3;
1110                                 /* top -> top pred */
1111                                 s->mv[i][0][0] = mx; 
1112                                 s->mv[i][0][1] = my << 1;
1113                                 s->mv[i][1][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1114                                 s->mv[i][1][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1115                                 m = 4 - m;
1116                                 s->mv[i][2][0] = mx;
1117                                 s->mv[i][2][1] = my << 1;
1118                                 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1119                                 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1120                             } else {
1121                                 mb_type |= MB_TYPE_16x16;
1122
1123                                 s->last_mv[i][0][1] = my;
1124                                 s->last_mv[i][1][1] = my;
1125                                 s->mv[i][0][0] = mx;
1126                                 s->mv[i][0][1] = my;
1127                                 s->mv[i][1][0] = ((mx + (mx > 0)) >> 1) + dmx;
1128                                 s->mv[i][1][1] = ((my + (my > 0)) >> 1) + dmy - 1 
1129                                     /* + 2 * cur_field */;
1130                             }
1131                         }
1132                         break;
1133                     }
1134                 }
1135             }
1136         }
1137         
1138         s->mb_intra = 0;
1139
1140         if (IS_PAT(mb_type)) {
1141             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1142             if (cbp < 0){
1143                 fprintf(stderr, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1144                 return -1;
1145             }
1146             cbp++;
1147
1148             if (s->mpeg2) {
1149                 for(i=0;i<6;i++) {
1150                     if (cbp & 32) {
1151                         if (mpeg2_decode_block_non_intra(s, block[i], i) < 0)
1152                             return -1;
1153                     } else {
1154                         s->block_last_index[i] = -1;
1155                     }
1156                     cbp+=cbp;
1157                 }
1158             } else {
1159                 for(i=0;i<6;i++) {
1160                     if (cbp & 32) {
1161                         if (mpeg1_decode_block_inter(s, block[i], i) < 0)
1162                             return -1;
1163                     } else {
1164                         s->block_last_index[i] = -1;
1165                     }
1166                     cbp+=cbp;
1167                 }
1168             }
1169         }else{
1170             for(i=0;i<6;i++)
1171                 s->block_last_index[i] = -1;
1172         }
1173     }
1174
1175     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
1176
1177     return 0;
1178 }
1179
1180 /* as h263, but only 17 codes */
1181 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
1182 {
1183     int code, sign, val, l, shift;
1184
1185     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
1186     if (code == 0) {
1187         return pred;
1188     }
1189     if (code < 0) {
1190         return 0xffff;
1191     }
1192
1193     sign = get_bits1(&s->gb);
1194     shift = fcode - 1;
1195     val = code;
1196     if (shift) {
1197         val = (val - 1) << shift;
1198         val |= get_bits(&s->gb, shift);
1199         val++;
1200     }
1201     if (sign)
1202         val = -val;
1203     val += pred;
1204     
1205     /* modulo decoding */
1206     l = 1 << (shift+4);
1207     val = ((val + l)&(l*2-1)) - l;
1208     return val;
1209 }
1210
1211 static inline int decode_dc(MpegEncContext *s, int component)
1212 {
1213     int code, diff;
1214
1215     if (component == 0) {
1216         code = get_vlc2(&s->gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
1217     } else {
1218         code = get_vlc2(&s->gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
1219     }
1220     if (code < 0){
1221         fprintf(stderr, "invalid dc code at %d %d\n", s->mb_x, s->mb_y);
1222         return 0xffff;
1223     }
1224     if (code == 0) {
1225         diff = 0;
1226     } else {
1227         diff = get_xbits(&s->gb, code);
1228     }
1229     return diff;
1230 }
1231
1232 static inline int mpeg1_decode_block_intra(MpegEncContext *s, 
1233                                DCTELEM *block, 
1234                                int n)
1235 {
1236     int level, dc, diff, i, j, run;
1237     int component;
1238     RLTable *rl = &rl_mpeg1;
1239     uint8_t * const scantable= s->intra_scantable.permutated;
1240     const uint16_t *quant_matrix= s->intra_matrix;
1241     const int qscale= s->qscale;
1242
1243     /* DC coef */
1244     component = (n <= 3 ? 0 : n - 4 + 1);
1245     diff = decode_dc(s, component);
1246     if (diff >= 0xffff)
1247         return -1;
1248     dc = s->last_dc[component];
1249     dc += diff;
1250     s->last_dc[component] = dc;
1251     block[0] = dc<<3;
1252     dprintf("dc=%d diff=%d\n", dc, diff);
1253     i = 0;
1254     {
1255         OPEN_READER(re, &s->gb);    
1256         /* now quantify & encode AC coefs */
1257         for(;;) {
1258             UPDATE_CACHE(re, &s->gb);
1259             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1260             
1261             if(level == 127){
1262                 break;
1263             } else if(level != 0) {
1264                 i += run;
1265                 j = scantable[i];
1266                 level= (level*qscale*quant_matrix[j])>>3;
1267                 level= (level-1)|1;
1268                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1269                 LAST_SKIP_BITS(re, &s->gb, 1);
1270             } else {
1271                 /* escape */
1272                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1273                 UPDATE_CACHE(re, &s->gb);
1274                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1275                 if (level == -128) {
1276                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1277                 } else if (level == 0) {
1278                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1279                 }
1280                 i += run;
1281                 j = scantable[i];
1282                 if(level<0){
1283                     level= -level;
1284                     level= (level*qscale*quant_matrix[j])>>3;
1285                     level= (level-1)|1;
1286                     level= -level;
1287                 }else{
1288                     level= (level*qscale*quant_matrix[j])>>3;
1289                     level= (level-1)|1;
1290                 }
1291             }
1292             if (i > 63){
1293                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1294                 return -1;
1295             }
1296
1297             block[j] = level;
1298         }
1299         CLOSE_READER(re, &s->gb);
1300     }
1301     s->block_last_index[n] = i;
1302    return 0;
1303 }
1304
1305 static inline int mpeg1_decode_block_inter(MpegEncContext *s, 
1306                                DCTELEM *block, 
1307                                int n)
1308 {
1309     int level, i, j, run;
1310     RLTable *rl = &rl_mpeg1;
1311     uint8_t * const scantable= s->intra_scantable.permutated;
1312     const uint16_t *quant_matrix= s->inter_matrix;
1313     const int qscale= s->qscale;
1314
1315     {
1316         int v;
1317         OPEN_READER(re, &s->gb);
1318         i = -1;
1319         /* special case for the first coef. no need to add a second vlc table */
1320         UPDATE_CACHE(re, &s->gb);
1321         v= SHOW_UBITS(re, &s->gb, 2);
1322         if (v & 2) {
1323             LAST_SKIP_BITS(re, &s->gb, 2);
1324             level= (3*qscale*quant_matrix[0])>>4;
1325             level= (level-1)|1;
1326             if(v&1)
1327                 level= -level;
1328             block[0] = level;
1329             i++;
1330         }
1331
1332         /* now quantify & encode AC coefs */
1333         for(;;) {
1334             UPDATE_CACHE(re, &s->gb);
1335             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1336             
1337             if(level == 127){
1338                 break;
1339             } else if(level != 0) {
1340                 i += run;
1341                 j = scantable[i];
1342                 level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1343                 level= (level-1)|1;
1344                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1345                 LAST_SKIP_BITS(re, &s->gb, 1);
1346             } else {
1347                 /* escape */
1348                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1349                 UPDATE_CACHE(re, &s->gb);
1350                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1351                 if (level == -128) {
1352                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1353                 } else if (level == 0) {
1354                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1355                 }
1356                 i += run;
1357                 j = scantable[i];
1358                 if(level<0){
1359                     level= -level;
1360                     level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1361                     level= (level-1)|1;
1362                     level= -level;
1363                 }else{
1364                     level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1365                     level= (level-1)|1;
1366                 }
1367             }
1368             if (i > 63){
1369                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1370                 return -1;
1371             }
1372
1373             block[j] = level;
1374         }
1375         CLOSE_READER(re, &s->gb);
1376     }
1377     s->block_last_index[n] = i;
1378     return 0;
1379 }
1380
1381 /* Also does unquantization here, since I will never support mpeg2
1382    encoding */
1383 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, 
1384                                DCTELEM *block, 
1385                                int n)
1386 {
1387     int level, i, j, run;
1388     RLTable *rl = &rl_mpeg1;
1389     uint8_t * const scantable= s->intra_scantable.permutated;
1390     const uint16_t *quant_matrix;
1391     const int qscale= s->qscale;
1392     int mismatch;
1393
1394     mismatch = 1;
1395
1396     {
1397         int v;
1398         OPEN_READER(re, &s->gb);
1399         i = -1;
1400         if (n < 4)
1401             quant_matrix = s->inter_matrix;
1402         else
1403             quant_matrix = s->chroma_inter_matrix;
1404
1405         /* special case for the first coef. no need to add a second vlc table */
1406         UPDATE_CACHE(re, &s->gb);
1407         v= SHOW_UBITS(re, &s->gb, 2);
1408         if (v & 2) {
1409             LAST_SKIP_BITS(re, &s->gb, 2);
1410             level= (3*qscale*quant_matrix[0])>>5;
1411             if(v&1)
1412                 level= -level;
1413             block[0] = level;
1414             mismatch ^= level;
1415             i++;
1416         }
1417
1418         /* now quantify & encode AC coefs */
1419         for(;;) {
1420             UPDATE_CACHE(re, &s->gb);
1421             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1422             
1423             if(level == 127){
1424                 break;
1425             } else if(level != 0) {
1426                 i += run;
1427                 j = scantable[i];
1428                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1429                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1430                 LAST_SKIP_BITS(re, &s->gb, 1);
1431             } else {
1432                 /* escape */
1433                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1434                 UPDATE_CACHE(re, &s->gb);
1435                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1436
1437                 i += run;
1438                 j = scantable[i];
1439                 if(level<0){
1440                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
1441                     level= -level;
1442                 }else{
1443                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1444                 }
1445             }
1446             if (i > 63){
1447                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1448                 return -1;
1449             }
1450             
1451             mismatch ^= level;
1452             block[j] = level;
1453         }
1454         CLOSE_READER(re, &s->gb);
1455     }
1456     block[63] ^= (mismatch & 1);
1457     
1458     s->block_last_index[n] = i;
1459     return 0;
1460 }
1461
1462 static inline int mpeg2_decode_block_intra(MpegEncContext *s, 
1463                                DCTELEM *block, 
1464                                int n)
1465 {
1466     int level, dc, diff, i, j, run;
1467     int component;
1468     RLTable *rl;
1469     uint8_t * const scantable= s->intra_scantable.permutated;
1470     const uint16_t *quant_matrix;
1471     const int qscale= s->qscale;
1472     int mismatch;
1473
1474     /* DC coef */
1475     if (n < 4){
1476         quant_matrix = s->intra_matrix;
1477         component = 0; 
1478     }else{
1479         quant_matrix = s->chroma_intra_matrix;
1480         component = n - 3;
1481     }
1482     diff = decode_dc(s, component);
1483     if (diff >= 0xffff)
1484         return -1;
1485     dc = s->last_dc[component];
1486     dc += diff;
1487     s->last_dc[component] = dc;
1488     block[0] = dc << (3 - s->intra_dc_precision);
1489     dprintf("dc=%d\n", block[0]);
1490     mismatch = block[0] ^ 1;
1491     i = 0;
1492     if (s->intra_vlc_format)
1493         rl = &rl_mpeg2;
1494     else
1495         rl = &rl_mpeg1;
1496
1497     {
1498         OPEN_READER(re, &s->gb);    
1499         /* now quantify & encode AC coefs */
1500         for(;;) {
1501             UPDATE_CACHE(re, &s->gb);
1502             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1503             
1504             if(level == 127){
1505                 break;
1506             } else if(level != 0) {
1507                 i += run;
1508                 j = scantable[i];
1509                 level= (level*qscale*quant_matrix[j])>>4;
1510                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1511                 LAST_SKIP_BITS(re, &s->gb, 1);
1512             } else {
1513                 /* escape */
1514                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1515                 UPDATE_CACHE(re, &s->gb);
1516                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1517                 i += run;
1518                 j = scantable[i];
1519                 if(level<0){
1520                     level= (-level*qscale*quant_matrix[j])>>4;
1521                     level= -level;
1522                 }else{
1523                     level= (level*qscale*quant_matrix[j])>>4;
1524                 }
1525             }
1526             if (i > 63){
1527                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1528                 return -1;
1529             }
1530             
1531             mismatch^= level;
1532             block[j] = level;
1533         }
1534         CLOSE_READER(re, &s->gb);
1535     }
1536     block[63]^= mismatch&1;
1537     
1538     s->block_last_index[n] = i;
1539     return 0;
1540 }
1541
1542 typedef struct Mpeg1Context {
1543     MpegEncContext mpeg_enc_ctx;
1544     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1545     int repeat_field; /* true if we must repeat the field */
1546 } Mpeg1Context;
1547
1548 static int mpeg_decode_init(AVCodecContext *avctx)
1549 {
1550     Mpeg1Context *s = avctx->priv_data;
1551     
1552     s->mpeg_enc_ctx.flags= avctx->flags;
1553     common_init(&s->mpeg_enc_ctx);
1554     init_vlcs(&s->mpeg_enc_ctx);
1555
1556     s->mpeg_enc_ctx_allocated = 0;
1557     s->mpeg_enc_ctx.picture_number = 0;
1558     s->repeat_field = 0;
1559     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1560     return 0;
1561 }
1562
1563 /* return the 8 bit start code value and update the search
1564    state. Return -1 if no start code found */
1565 static int find_start_code(uint8_t **pbuf_ptr, uint8_t *buf_end)
1566 {
1567     uint8_t *buf_ptr;
1568     unsigned int state=0xFFFFFFFF, v;
1569     int val;
1570
1571     buf_ptr = *pbuf_ptr;
1572     while (buf_ptr < buf_end) {
1573         v = *buf_ptr++;
1574         if (state == 0x000001) {
1575             state = ((state << 8) | v) & 0xffffff;
1576             val = state;
1577             goto found;
1578         }
1579         state = ((state << 8) | v) & 0xffffff;
1580     }
1581     val = -1;
1582  found:
1583     *pbuf_ptr = buf_ptr;
1584     return val;
1585 }
1586
1587 static int mpeg1_decode_picture(AVCodecContext *avctx, 
1588                                 uint8_t *buf, int buf_size)
1589 {
1590     Mpeg1Context *s1 = avctx->priv_data;
1591     MpegEncContext *s = &s1->mpeg_enc_ctx;
1592     int ref, f_code;
1593
1594     init_get_bits(&s->gb, buf, buf_size*8);
1595
1596     ref = get_bits(&s->gb, 10); /* temporal ref */
1597     s->pict_type = get_bits(&s->gb, 3);
1598     dprintf("pict_type=%d number=%d\n", s->pict_type, s->picture_number);
1599
1600     skip_bits(&s->gb, 16);
1601     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
1602         s->full_pel[0] = get_bits1(&s->gb);
1603         f_code = get_bits(&s->gb, 3);
1604         if (f_code == 0)
1605             return -1;
1606         s->mpeg_f_code[0][0] = f_code;
1607         s->mpeg_f_code[0][1] = f_code;
1608     }
1609     if (s->pict_type == B_TYPE) {
1610         s->full_pel[1] = get_bits1(&s->gb);
1611         f_code = get_bits(&s->gb, 3);
1612         if (f_code == 0)
1613             return -1;
1614         s->mpeg_f_code[1][0] = f_code;
1615         s->mpeg_f_code[1][1] = f_code;
1616     }
1617     s->current_picture.pict_type= s->pict_type;
1618     s->current_picture.key_frame= s->pict_type == I_TYPE;
1619     
1620     s->y_dc_scale = 8;
1621     s->c_dc_scale = 8;
1622     s->first_slice = 1;
1623     return 0;
1624 }
1625
1626 static void mpeg_decode_sequence_extension(MpegEncContext *s)
1627 {
1628     int horiz_size_ext, vert_size_ext;
1629     int bit_rate_ext, vbv_buf_ext;
1630     int frame_rate_ext_n, frame_rate_ext_d;
1631     float aspect;
1632
1633     skip_bits(&s->gb, 8); /* profil and level */
1634     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1635     skip_bits(&s->gb, 2); /* chroma_format */
1636     horiz_size_ext = get_bits(&s->gb, 2);
1637     vert_size_ext = get_bits(&s->gb, 2);
1638     s->width |= (horiz_size_ext << 12);
1639     s->height |= (vert_size_ext << 12);
1640     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1641     s->bit_rate = ((s->bit_rate / 400) | (bit_rate_ext << 12)) * 400;
1642     skip_bits1(&s->gb); /* marker */
1643     vbv_buf_ext = get_bits(&s->gb, 8);
1644     s->low_delay = get_bits1(&s->gb);
1645     frame_rate_ext_n = get_bits(&s->gb, 2);
1646     frame_rate_ext_d = get_bits(&s->gb, 5);
1647     av_reduce(
1648         &s->avctx->frame_rate, 
1649         &s->avctx->frame_rate_base, 
1650         frame_rate_tab[s->frame_rate_index] * (frame_rate_ext_n+1),
1651         MPEG1_FRAME_RATE_BASE * (frame_rate_ext_d+1),
1652         1<<30);
1653
1654     dprintf("sequence extension\n");
1655     s->mpeg2 = 1;
1656     s->avctx->sub_id = 2; /* indicates mpeg2 found */
1657
1658     aspect= mpeg2_aspect[s->aspect_ratio_info];
1659     if(aspect>0.0)      s->avctx->aspect_ratio= s->width/(aspect*s->height);
1660     else if(aspect<0.0) s->avctx->aspect_ratio= -1.0/aspect;
1661 }
1662
1663 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1664 {
1665     int i, v, j;
1666
1667     dprintf("matrix extension\n");
1668
1669     if (get_bits1(&s->gb)) {
1670         for(i=0;i<64;i++) {
1671             v = get_bits(&s->gb, 8);
1672             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1673             s->intra_matrix[j] = v;
1674             s->chroma_intra_matrix[j] = v;
1675         }
1676     }
1677     if (get_bits1(&s->gb)) {
1678         for(i=0;i<64;i++) {
1679             v = get_bits(&s->gb, 8);
1680             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1681             s->inter_matrix[j] = v;
1682             s->chroma_inter_matrix[j] = v;
1683         }
1684     }
1685     if (get_bits1(&s->gb)) {
1686         for(i=0;i<64;i++) {
1687             v = get_bits(&s->gb, 8);
1688             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1689             s->chroma_intra_matrix[j] = v;
1690         }
1691     }
1692     if (get_bits1(&s->gb)) {
1693         for(i=0;i<64;i++) {
1694             v = get_bits(&s->gb, 8);
1695             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1696             s->chroma_inter_matrix[j] = v;
1697         }
1698     }
1699 }
1700
1701 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1702 {
1703     s->full_pel[0] = s->full_pel[1] = 0;
1704     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1705     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1706     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1707     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1708     s->intra_dc_precision = get_bits(&s->gb, 2);
1709     s->picture_structure = get_bits(&s->gb, 2);
1710     s->top_field_first = get_bits1(&s->gb);
1711     s->frame_pred_frame_dct = get_bits1(&s->gb);
1712     s->concealment_motion_vectors = get_bits1(&s->gb);
1713     s->q_scale_type = get_bits1(&s->gb);
1714     s->intra_vlc_format = get_bits1(&s->gb);
1715     s->alternate_scan = get_bits1(&s->gb);
1716     s->repeat_first_field = get_bits1(&s->gb);
1717     s->chroma_420_type = get_bits1(&s->gb);
1718     s->progressive_frame = get_bits1(&s->gb);
1719     
1720     if(s->picture_structure == PICT_FRAME)
1721         s->first_field=0;
1722     else{
1723         s->first_field ^= 1;
1724         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1725     }
1726     
1727     if(s->alternate_scan){
1728         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1729         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1730         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
1731         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
1732     }else{
1733         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1734         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1735         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
1736         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
1737     }
1738     
1739     /* composite display not parsed */
1740     dprintf("intra_dc_precision=%d\n", s->intra_dc_precision);
1741     dprintf("picture_structure=%d\n", s->picture_structure);
1742     dprintf("top field first=%d\n", s->top_field_first);
1743     dprintf("repeat first field=%d\n", s->repeat_first_field);
1744     dprintf("conceal=%d\n", s->concealment_motion_vectors);
1745     dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
1746     dprintf("alternate_scan=%d\n", s->alternate_scan);
1747     dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1748     dprintf("progressive_frame=%d\n", s->progressive_frame);
1749 }
1750
1751 static void mpeg_decode_extension(AVCodecContext *avctx, 
1752                                   uint8_t *buf, int buf_size)
1753 {
1754     Mpeg1Context *s1 = avctx->priv_data;
1755     MpegEncContext *s = &s1->mpeg_enc_ctx;
1756     int ext_type;
1757
1758     init_get_bits(&s->gb, buf, buf_size*8);
1759     
1760     ext_type = get_bits(&s->gb, 4);
1761     switch(ext_type) {
1762     case 0x1:
1763         /* sequence ext */
1764         mpeg_decode_sequence_extension(s);
1765         break;
1766     case 0x3:
1767         /* quant matrix extension */
1768         mpeg_decode_quant_matrix_extension(s);
1769         break;
1770     case 0x8:
1771         /* picture extension */
1772         mpeg_decode_picture_coding_extension(s);
1773         break;
1774     }
1775 }
1776
1777 #define DECODE_SLICE_FATAL_ERROR -2
1778 #define DECODE_SLICE_ERROR -1
1779 #define DECODE_SLICE_OK 0
1780
1781 /**
1782  * decodes a slice.
1783  * @return DECODE_SLICE_FATAL_ERROR if a non recoverable error occured<br>
1784  *         DECODE_SLICE_ERROR if the slice is damaged<br>
1785  *         DECODE_SLICE_OK if this slice is ok<br>
1786  */
1787 static int mpeg_decode_slice(AVCodecContext *avctx, 
1788                               AVFrame *pict,
1789                               int start_code,
1790                               uint8_t **buf, int buf_size)
1791 {
1792     Mpeg1Context *s1 = avctx->priv_data;
1793     MpegEncContext *s = &s1->mpeg_enc_ctx;
1794     int ret;
1795     const int field_pic= s->picture_structure != PICT_FRAME;
1796
1797     s->resync_mb_x= s->mb_x = 
1798     s->resync_mb_y= s->mb_y = -1;
1799     
1800     start_code = (start_code - 1) & 0xff;
1801     if (start_code >= s->mb_height){
1802         fprintf(stderr, "slice below image (%d >= %d)\n", start_code, s->mb_height);
1803         return -1;
1804     }
1805     
1806     ff_mpeg1_clean_buffers(s);
1807     s->interlaced_dct = 0;
1808         
1809     /* start frame decoding */
1810     if (s->first_slice) {
1811       if(s->first_field || s->picture_structure==PICT_FRAME){
1812         if(MPV_frame_start(s, avctx) < 0)
1813             return DECODE_SLICE_FATAL_ERROR;
1814
1815         ff_er_frame_start(s);
1816
1817         /* first check if we must repeat the frame */
1818         s->current_picture.repeat_pict = 0;
1819
1820         if (s->repeat_first_field) {
1821             if (s->progressive_sequence) {
1822                 if (s->top_field_first)
1823                     s->current_picture.repeat_pict = 4;
1824                 else
1825                     s->current_picture.repeat_pict = 2;
1826             } else if (s->progressive_frame) {
1827                 s->current_picture.repeat_pict = 1;
1828             }
1829         }         
1830 //        printf("%d \n", s->current_picture.repeat_pict);
1831
1832         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1833              printf("qp:%d fc:%2d%2d%2d%2d %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n", 
1834                  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],
1835                  s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")), 
1836                  s->progressive_sequence ? "pro" :"", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"", 
1837                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1838                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1839         }
1840       }else{ //second field
1841             int i;
1842             
1843             if(!s->current_picture_ptr){
1844                 fprintf(stderr, "first field missing\n");
1845                 return -1;
1846             }
1847             
1848             for(i=0; i<4; i++){
1849                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1850                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1851                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1852                 } 
1853             }
1854       }
1855     }
1856     s->first_slice = 0;
1857
1858     init_get_bits(&s->gb, *buf, buf_size*8);
1859
1860     s->qscale = get_qscale(s);
1861     if(s->qscale == 0){
1862         fprintf(stderr, "qscale == 0\n");
1863         return -1;
1864     }
1865     
1866     /* extra slice info */
1867     while (get_bits1(&s->gb) != 0) {
1868         skip_bits(&s->gb, 8);
1869     }
1870     
1871     s->mb_x=0;
1872
1873     for(;;) {
1874         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1875         if (code < 0){
1876             fprintf(stderr, "first mb_incr damaged\n");
1877             return -1;
1878         }
1879         if (code >= 33) {
1880             if (code == 33) {
1881                 s->mb_x += 33;
1882             }
1883             /* otherwise, stuffing, nothing to do */
1884         } else {
1885             s->mb_x += code;
1886             break;
1887         }
1888     }
1889     
1890     s->resync_mb_x= s->mb_x;
1891     s->resync_mb_y= s->mb_y = start_code;
1892     s->mb_skip_run= 0;
1893
1894     for(;;) {
1895         s->dsp.clear_blocks(s->block[0]);
1896
1897         ret = mpeg_decode_mb(s, s->block);
1898
1899         dprintf("ret=%d\n", ret);
1900         if (ret < 0)
1901             return -1;
1902             
1903         if(s->motion_val && s->pict_type != B_TYPE){ //note motion_val is normally NULL unless we want to extract the MVs
1904             const int wrap = s->block_wrap[0];
1905             const int xy = s->mb_x*2 + 1 + (s->mb_y*2 +1)*wrap;
1906             int motion_x, motion_y;
1907
1908             if (s->mb_intra) {
1909                 motion_x = motion_y = 0;
1910             }else if (s->mv_type == MV_TYPE_16X16) {
1911                 motion_x = s->mv[0][0][0];
1912                 motion_y = s->mv[0][0][1];
1913             } else /*if (s->mv_type == MV_TYPE_FIELD)*/ {
1914                 motion_x = s->mv[0][0][0] + s->mv[0][1][0];
1915                 motion_y = s->mv[0][0][1] + s->mv[0][1][1];
1916                 motion_x = (motion_x>>1) | (motion_x&1);
1917             }
1918             s->motion_val[xy][0] = motion_x;
1919             s->motion_val[xy][1] = motion_y;
1920             s->motion_val[xy + 1][0] = motion_x;
1921             s->motion_val[xy + 1][1] = motion_y;
1922             s->motion_val[xy + wrap][0] = motion_x;
1923             s->motion_val[xy + wrap][1] = motion_y;
1924             s->motion_val[xy + 1 + wrap][0] = motion_x;
1925             s->motion_val[xy + 1 + wrap][1] = motion_y;
1926         }
1927         
1928         MPV_decode_mb(s, s->block);
1929
1930         if (++s->mb_x >= s->mb_width) {
1931             if(s->picture_structure==PICT_FRAME){
1932                 ff_draw_horiz_band(s, 16*s->mb_y, 16);
1933             }else{
1934                 if(!s->first_field){
1935                     ff_draw_horiz_band(s, 32*s->mb_y, 32);
1936                 }
1937             }
1938
1939             s->mb_x = 0;
1940             s->mb_y++;
1941
1942             if(s->mb_y<<field_pic >= s->mb_height){
1943                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1944
1945                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)))
1946                    || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
1947                     fprintf(stderr, "end missmatch left=%d\n", left);
1948                     return -1;
1949                 }else
1950                     goto eos;
1951             }
1952         }
1953
1954         /* skip mb handling */
1955         if (s->mb_skip_run == -1) {
1956             /* read again increment */
1957             s->mb_skip_run = 0;
1958             for(;;) {
1959                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1960                 if (code < 0){
1961                     fprintf(stderr, "mb incr damaged\n");
1962                     return -1;
1963                 }
1964                 if (code >= 33) {
1965                     if (code == 33) {
1966                         s->mb_skip_run += 33;
1967                     }else if(code == 35){
1968                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1969                             fprintf(stderr, "slice missmatch\n");
1970                             return -1;
1971                         }
1972                         goto eos; /* end of slice */
1973                     }
1974                     /* otherwise, stuffing, nothing to do */
1975                 } else {
1976                     s->mb_skip_run += code;
1977                     break;
1978                 }
1979             }
1980         }
1981     }
1982 eos: // end of slice
1983     *buf += get_bits_count(&s->gb)/8 - 1;
1984 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1985     return 0;
1986 }
1987
1988 /**
1989  * handles slice ends.
1990  * @return 1 if it seems to be the last slice of 
1991  */
1992 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1993 {
1994     Mpeg1Context *s1 = avctx->priv_data;
1995     MpegEncContext *s = &s1->mpeg_enc_ctx;
1996        
1997     if (!s1->mpeg_enc_ctx_allocated)
1998         return 0;
1999
2000     /* end of slice reached */
2001     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
2002         /* end of image */
2003
2004         if(s->mpeg2){
2005             s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
2006         }else
2007             s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG1;
2008
2009         ff_er_frame_end(s);
2010
2011         MPV_frame_end(s);
2012
2013         if (s->pict_type == B_TYPE || s->low_delay) {
2014             *pict= *(AVFrame*)&s->current_picture;
2015             ff_print_debug_info(s, s->current_picture_ptr);
2016         } else {
2017             s->picture_number++;
2018             /* latency of 1 frame for I and P frames */
2019             /* XXX: use another variable than picture_number */
2020             if (s->last_picture_ptr != NULL) {
2021                 *pict= *(AVFrame*)&s->last_picture;
2022                  ff_print_debug_info(s, s->last_picture_ptr);
2023             }
2024         }
2025         return 1;
2026     } else {
2027         return 0;
2028     }
2029 }
2030
2031 static int mpeg1_decode_sequence(AVCodecContext *avctx, 
2032                                  uint8_t *buf, int buf_size)
2033 {
2034     Mpeg1Context *s1 = avctx->priv_data;
2035     MpegEncContext *s = &s1->mpeg_enc_ctx;
2036     int width, height, i, v, j;
2037     float aspect;
2038
2039     init_get_bits(&s->gb, buf, buf_size*8);
2040
2041     width = get_bits(&s->gb, 12);
2042     height = get_bits(&s->gb, 12);
2043     s->aspect_ratio_info= get_bits(&s->gb, 4);
2044     if(!s->mpeg2){
2045         aspect= mpeg1_aspect[s->aspect_ratio_info];
2046         if(aspect!=0.0) avctx->aspect_ratio= width/(aspect*height);
2047     }
2048
2049     s->frame_rate_index = get_bits(&s->gb, 4);
2050     if (s->frame_rate_index == 0)
2051         return -1;
2052     s->bit_rate = get_bits(&s->gb, 18) * 400;
2053     if (get_bits1(&s->gb) == 0) /* marker */
2054         return -1;
2055     if (width <= 0 || height <= 0 ||
2056         (width % 2) != 0 || (height % 2) != 0)
2057         return -1;
2058     if (width != s->width ||
2059         height != s->height) {
2060         /* start new mpeg1 context decoding */
2061         s->out_format = FMT_MPEG1;
2062         if (s1->mpeg_enc_ctx_allocated) {
2063             MPV_common_end(s);
2064         }
2065         s->width = width;
2066         s->height = height;
2067         avctx->has_b_frames= 1;
2068         s->avctx = avctx;
2069         avctx->width = width;
2070         avctx->height = height;
2071         av_reduce(
2072             &avctx->frame_rate, 
2073             &avctx->frame_rate_base,
2074             frame_rate_tab[s->frame_rate_index],
2075             MPEG1_FRAME_RATE_BASE, //FIXME store in allready reduced form 
2076             1<<30
2077             );
2078         avctx->bit_rate = s->bit_rate;
2079         
2080         if (MPV_common_init(s) < 0)
2081             return -1;
2082         s1->mpeg_enc_ctx_allocated = 1;
2083     }
2084
2085     skip_bits(&s->gb, 10); /* vbv_buffer_size */
2086     skip_bits(&s->gb, 1);
2087
2088     /* get matrix */
2089     if (get_bits1(&s->gb)) {
2090         for(i=0;i<64;i++) {
2091             v = get_bits(&s->gb, 8);
2092             j = s->intra_scantable.permutated[i];
2093             s->intra_matrix[j] = v;
2094             s->chroma_intra_matrix[j] = v;
2095         }
2096 #ifdef DEBUG
2097         dprintf("intra matrix present\n");
2098         for(i=0;i<64;i++)
2099             dprintf(" %d", s->intra_matrix[s->intra_scantable.permutated[i]]);
2100         printf("\n");
2101 #endif
2102     } else {
2103         for(i=0;i<64;i++) {
2104             int j= s->dsp.idct_permutation[i];
2105             v = ff_mpeg1_default_intra_matrix[i];
2106             s->intra_matrix[j] = v;
2107             s->chroma_intra_matrix[j] = v;
2108         }
2109     }
2110     if (get_bits1(&s->gb)) {
2111         for(i=0;i<64;i++) {
2112             v = get_bits(&s->gb, 8);
2113             j = s->intra_scantable.permutated[i];
2114             s->inter_matrix[j] = v;
2115             s->chroma_inter_matrix[j] = v;
2116         }
2117 #ifdef DEBUG
2118         dprintf("non intra matrix present\n");
2119         for(i=0;i<64;i++)
2120             dprintf(" %d", s->inter_matrix[s->intra_scantable.permutated[i]]);
2121         printf("\n");
2122 #endif
2123     } else {
2124         for(i=0;i<64;i++) {
2125             int j= s->dsp.idct_permutation[i];
2126             v = ff_mpeg1_default_non_intra_matrix[i];
2127             s->inter_matrix[j] = v;
2128             s->chroma_inter_matrix[j] = v;
2129         }
2130     }
2131
2132     /* we set mpeg2 parameters so that it emulates mpeg1 */
2133     s->progressive_sequence = 1;
2134     s->progressive_frame = 1;
2135     s->picture_structure = PICT_FRAME;
2136     s->frame_pred_frame_dct = 1;
2137     s->mpeg2 = 0;
2138     avctx->sub_id = 1; /* indicates mpeg1 */
2139     return 0;
2140 }
2141
2142 static void mpeg_decode_user_data(AVCodecContext *avctx, 
2143                                   const uint8_t *buf, int buf_size)
2144 {
2145     const uint8_t *p;
2146     int len, flags;
2147     p = buf;
2148     len = buf_size;
2149
2150     /* we parse the DTG active format information */
2151     if (len >= 5 &&
2152         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2153         flags = p[4];
2154         p += 5;
2155         len -= 5;
2156         if (flags & 0x80) {
2157             /* skip event id */
2158             if (len < 2)
2159                 return;
2160             p += 2;
2161             len -= 2;
2162         }
2163         if (flags & 0x40) {
2164             if (len < 1)
2165                 return;
2166             avctx->dtg_active_format = p[0] & 0x0f;
2167         }
2168     }
2169 }
2170
2171 /**
2172  * finds the end of the current frame in the bitstream.
2173  * @return the position of the first byte of the next frame, or -1
2174  */
2175 static int mpeg1_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
2176     ParseContext *pc= &s->parse_context;
2177     int i;
2178     uint32_t state;
2179     
2180     state= pc->state;
2181     
2182     i=0;
2183     if(!pc->frame_start_found){
2184         for(i=0; i<buf_size; i++){
2185             state= (state<<8) | buf[i];
2186             if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2187                 i++;
2188                 pc->frame_start_found=1;
2189                 break;
2190             }
2191         }
2192     }
2193     
2194     if(pc->frame_start_found){
2195         for(; i<buf_size; i++){
2196             state= (state<<8) | buf[i];
2197             if((state&0xFFFFFF00) == 0x100){
2198                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2199                     pc->frame_start_found=0;
2200                     pc->state=-1; 
2201                     return i-3;
2202                 }
2203             }
2204         }
2205     }        
2206     pc->state= state;
2207     return END_NOT_FOUND;
2208 }
2209
2210 /* handle buffering and image synchronisation */
2211 static int mpeg_decode_frame(AVCodecContext *avctx, 
2212                              void *data, int *data_size,
2213                              uint8_t *buf, int buf_size)
2214 {
2215     Mpeg1Context *s = avctx->priv_data;
2216     uint8_t *buf_end, *buf_ptr;
2217     int ret, start_code, input_size;
2218     AVFrame *picture = data;
2219     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2220     dprintf("fill_buffer\n");
2221
2222     *data_size = 0;
2223
2224     /* special case for last picture */
2225     if (buf_size == 0) {
2226         if (s2->picture_number > 0) {
2227             *picture= *(AVFrame*)&s2->next_picture;
2228
2229             *data_size = sizeof(AVFrame);
2230         }
2231         return 0;
2232     }
2233
2234     if(s2->flags&CODEC_FLAG_TRUNCATED){
2235         int next= mpeg1_find_frame_end(s2, buf, buf_size);
2236         
2237         if( ff_combine_frame(s2, next, &buf, &buf_size) < 0 )
2238             return buf_size;
2239     }    
2240     
2241     buf_ptr = buf;
2242     buf_end = buf + buf_size;
2243
2244 #if 0    
2245     if (s->repeat_field % 2 == 1) { 
2246         s->repeat_field++;
2247         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2248         //        s2->picture_number, s->repeat_field);
2249         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2250             *data_size = sizeof(AVPicture);
2251             goto the_end;
2252         }
2253     }
2254 #endif
2255     for(;;) {
2256         /* find start next code */
2257         start_code = find_start_code(&buf_ptr, buf_end);
2258         if (start_code < 0){
2259             if (slice_end(avctx, picture)) {
2260                 if(s2->last_picture_ptr) //FIXME merge with the stuff in mpeg_decode_slice
2261                     *data_size = sizeof(AVPicture);
2262             }
2263             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2264         }
2265         
2266         input_size = buf_end - buf_ptr;
2267
2268         if(avctx->debug & FF_DEBUG_STARTCODE){
2269             printf("%3X at %d left %d\n", start_code, buf_ptr-buf, input_size);
2270         }
2271
2272                 /* prepare data for next start code */
2273                 switch(start_code) {
2274                 case SEQ_START_CODE:
2275                     mpeg1_decode_sequence(avctx, buf_ptr, 
2276                                           input_size);
2277                     break;
2278                             
2279                 case PICTURE_START_CODE:
2280                     /* we have a complete image : we try to decompress it */
2281                     mpeg1_decode_picture(avctx, 
2282                                          buf_ptr, input_size);
2283                     break;
2284                 case EXT_START_CODE:
2285                     mpeg_decode_extension(avctx,
2286                                           buf_ptr, input_size);
2287                     break;
2288                 case USER_START_CODE:
2289                     mpeg_decode_user_data(avctx, 
2290                                           buf_ptr, input_size);
2291                     break;
2292                 default:
2293                     if (start_code >= SLICE_MIN_START_CODE &&
2294                         start_code <= SLICE_MAX_START_CODE) {
2295                         
2296                         /* skip b frames if we dont have reference frames */
2297                         if(s2->last_picture_ptr==NULL && s2->pict_type==B_TYPE) break;
2298                         /* skip b frames if we are in a hurry */
2299                         if(avctx->hurry_up && s2->pict_type==B_TYPE) break;
2300                         /* skip everything if we are in a hurry>=5 */
2301                         if(avctx->hurry_up>=5) break;
2302                         
2303                         if (!s->mpeg_enc_ctx_allocated) break;
2304
2305                         ret = mpeg_decode_slice(avctx, picture,
2306                                                 start_code, &buf_ptr, input_size);
2307                         emms_c();
2308
2309                         if(ret < 0){
2310                             if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2311                                 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);
2312                             if(ret==DECODE_SLICE_FATAL_ERROR) return -1;
2313                         }else{
2314                             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);
2315                         }
2316                     }
2317                     break;
2318                 }
2319     }
2320 }
2321
2322 static int mpeg_decode_end(AVCodecContext *avctx)
2323 {
2324     Mpeg1Context *s = avctx->priv_data;
2325
2326     if (s->mpeg_enc_ctx_allocated)
2327         MPV_common_end(&s->mpeg_enc_ctx);
2328     return 0;
2329 }
2330
2331 AVCodec mpeg_decoder = {
2332     "mpegvideo",
2333     CODEC_TYPE_VIDEO,
2334     CODEC_ID_MPEG1VIDEO,
2335     sizeof(Mpeg1Context),
2336     mpeg_decode_init,
2337     NULL,
2338     mpeg_decode_end,
2339     mpeg_decode_frame,
2340     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
2341 };