git.sesse.net Git - ffmpeg/blob - 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             mpeg_decode_motion(s, s->mpeg_f_code[0][0], 0);
 963             mpeg_decode_motion(s, s->mpeg_f_code[0][1], 0);
 964             skip_bits1(&s->gb); /* marker */
 965         }
 966         s->mb_intra = 1;
 967         memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 968
 969         if (s->mpeg2) {
 970             for(i=0;i<6;i++) {
 971                 if (mpeg2_decode_block_intra(s, block[i], i) < 0)
 972                     return -1;
 973             }
 974         } else {
 975             for(i=0;i<6;i++) {
 976                 if (mpeg1_decode_block_intra(s, block[i], i) < 0)
 977                     return -1;
 978             }
 979         }
 980     } else {
 981         if (mb_type & MB_TYPE_ZERO_MV){
 982             assert(mb_type & MB_TYPE_PAT);
 983
 984             /* compute dct type */
 985             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
 986                 !s->frame_pred_frame_dct) {
 987                 s->interlaced_dct = get_bits1(&s->gb);
 988             }
 989
 990             if (IS_QUANT(mb_type))
 991                 s->qscale = get_qscale(s);
 992
 993             s->mv_dir = MV_DIR_FORWARD;
 994             s->mv_type = MV_TYPE_16X16;
 995             s->last_mv[0][0][0] = 0;
 996             s->last_mv[0][0][1] = 0;
 997             s->last_mv[0][1][0] = 0;
 998             s->last_mv[0][1][1] = 0;
 999             s->mv[0][0][0] = 0;
1000             s->mv[0][0][1] = 0;
1001         }else{
1002             assert(mb_type & MB_TYPE_L0L1);
1003 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
1004             /* get additionnal motion vector type */
1005             if (s->frame_pred_frame_dct)
1006                 motion_type = MT_FRAME;
1007             else{
1008                 motion_type = get_bits(&s->gb, 2);
1009             }
1010
1011             /* compute dct type */
1012             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1013                 !s->frame_pred_frame_dct && IS_PAT(mb_type)) {
1014                 s->interlaced_dct = get_bits1(&s->gb);
1015             }
1016
1017             if (IS_QUANT(mb_type))
1018                 s->qscale = get_qscale(s);
1019
1020             /* motion vectors */
1021             s->mv_dir = 0;
1022             for(i=0;i<2;i++) {
1023                 if (USES_LIST(mb_type, i)) {
1024                     s->mv_dir |= (MV_DIR_FORWARD >> i);
1025                     dprintf("motion_type=%d\n", motion_type);
1026                     switch(motion_type) {
1027                     case MT_FRAME: /* or MT_16X8 */
1028                         if (s->picture_structure == PICT_FRAME) {
1029                             /* MT_FRAME */
1030                             mb_type |= MB_TYPE_16x16;
1031                             s->mv_type = MV_TYPE_16X16;
1032                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
1033                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
1034                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
1035                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
1036                             /* full_pel: only for mpeg1 */
1037                             if (s->full_pel[i]){
1038                                 s->mv[i][0][0] <<= 1;
1039                                 s->mv[i][0][1] <<= 1;
1040                             }
1041                         } else {
1042                             /* MT_16X8 */
1043                             mb_type |= MB_TYPE_16x8;
1044                             s->mv_type = MV_TYPE_16X8;
1045                             for(j=0;j<2;j++) {
1046                                 s->field_select[i][j] = get_bits1(&s->gb);
1047                                 for(k=0;k<2;k++) {
1048                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1049                                                              s->last_mv[i][j][k]);
1050                                     s->last_mv[i][j][k] = val;
1051                                     s->mv[i][j][k] = val;
1052                                 }
1053                             }
1054                         }
1055                         break;
1056                     case MT_FIELD:
1057                         s->mv_type = MV_TYPE_FIELD;
1058                         if (s->picture_structure == PICT_FRAME) {
1059                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
1060                             for(j=0;j<2;j++) {
1061                                 s->field_select[i][j] = get_bits1(&s->gb);
1062                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1063                                                          s->last_mv[i][j][0]);
1064                                 s->last_mv[i][j][0] = val;
1065                                 s->mv[i][j][0] = val;
1066                                 dprintf("fmx=%d\n", val);
1067                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1068                                                          s->last_mv[i][j][1] >> 1);
1069                                 s->last_mv[i][j][1] = val << 1;
1070                                 s->mv[i][j][1] = val;
1071                                 dprintf("fmy=%d\n", val);
1072                             }
1073                         } else {
1074                             mb_type |= MB_TYPE_16x16;
1075                             s->field_select[i][0] = get_bits1(&s->gb);
1076                             for(k=0;k<2;k++) {
1077                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1078                                                          s->last_mv[i][0][k]);
1079                                 s->last_mv[i][0][k] = val;
1080                                 s->last_mv[i][1][k] = val;
1081                                 s->mv[i][0][k] = val;
1082                             }
1083                         }
1084                         break;
1085                     case MT_DMV:
1086                         {
1087                             int dmx, dmy, mx, my, m;
1088
1089                             mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1090                                                     s->last_mv[i][0][0]);
1091                             s->last_mv[i][0][0] = mx;
1092                             s->last_mv[i][1][0] = mx;
1093                             dmx = get_dmv(s);
1094                             my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1095                                                     s->last_mv[i][0][1] >> 1);
1096                             dmy = get_dmv(s);
1097                             s->mv_type = MV_TYPE_DMV;
1098                             /* XXX: totally broken */
1099                             if (s->picture_structure == PICT_FRAME) {
1100                                 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1101
1102                                 s->last_mv[i][0][1] = my << 1;
1103                                 s->last_mv[i][1][1] = my << 1;
1104
1105                                 m = s->top_field_first ? 1 : 3;
1106                                 /* top -> top pred */
1107                                 s->mv[i][0][0] = mx;
1108                                 s->mv[i][0][1] = my << 1;
1109                                 s->mv[i][1][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1110                                 s->mv[i][1][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1111                                 m = 4 - m;
1112                                 s->mv[i][2][0] = mx;
1113                                 s->mv[i][2][1] = my << 1;
1114                                 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1115                                 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1116                             } else {
1117                                 mb_type |= MB_TYPE_16x16;
1118
1119                                 s->last_mv[i][0][1] = my;
1120                                 s->last_mv[i][1][1] = my;
1121                                 s->mv[i][0][0] = mx;
1122                                 s->mv[i][0][1] = my;
1123                                 s->mv[i][1][0] = ((mx + (mx > 0)) >> 1) + dmx;
1124                                 s->mv[i][1][1] = ((my + (my > 0)) >> 1) + dmy - 1
1125                                     /* + 2 * cur_field */;
1126                             }
1127                         }
1128                         break;
1129                     }
1130                 }
1131             }
1132         }
1133
1134         s->mb_intra = 0;
1135
1136         if (IS_PAT(mb_type)) {
1137             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1138             if (cbp < 0){
1139                 fprintf(stderr, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1140                 return -1;
1141             }
1142             cbp++;
1143
1144             if (s->mpeg2) {
1145                 for(i=0;i<6;i++) {
1146                     if (cbp & 32) {
1147                         if (mpeg2_decode_block_non_intra(s, block[i], i) < 0)
1148                             return -1;
1149                     } else {
1150                         s->block_last_index[i] = -1;
1151                     }
1152                     cbp+=cbp;
1153                 }
1154             } else {
1155                 for(i=0;i<6;i++) {
1156                     if (cbp & 32) {
1157                         if (mpeg1_decode_block_inter(s, block[i], i) < 0)
1158                             return -1;
1159                     } else {
1160                         s->block_last_index[i] = -1;
1161                     }
1162                     cbp+=cbp;
1163                 }
1164             }
1165         }else{
1166             for(i=0;i<6;i++)
1167                 s->block_last_index[i] = -1;
1168         }
1169     }
1170
1171     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
1172
1173     return 0;
1174 }
1175
1176 /* as h263, but only 17 codes */
1177 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
1178 {
1179     int code, sign, val, l, shift;
1180
1181     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
1182     if (code == 0) {
1183         return pred;
1184     }
1185     if (code < 0) {
1186         return 0xffff;
1187     }
1188
1189     sign = get_bits1(&s->gb);
1190     shift = fcode - 1;
1191     val = code;
1192     if (shift) {
1193         val = (val - 1) << shift;
1194         val |= get_bits(&s->gb, shift);
1195         val++;
1196     }
1197     if (sign)
1198         val = -val;
1199     val += pred;
1200
1201     /* modulo decoding */
1202     l = 1 << (shift+4);
1203     val = ((val + l)&(l*2-1)) - l;
1204     return val;
1205 }
1206
1207 static inline int decode_dc(MpegEncContext *s, int component)
1208 {
1209     int code, diff;
1210
1211     if (component == 0) {
1212         code = get_vlc2(&s->gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
1213     } else {
1214         code = get_vlc2(&s->gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
1215     }
1216     if (code < 0){
1217         fprintf(stderr, "invalid dc code at %d %d\n", s->mb_x, s->mb_y);
1218         return 0xffff;
1219     }
1220     if (code == 0) {
1221         diff = 0;
1222     } else {
1223         diff = get_xbits(&s->gb, code);
1224     }
1225     return diff;
1226 }
1227
1228 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
1229                                DCTELEM *block,
1230                                int n)
1231 {
1232     int level, dc, diff, i, j, run;
1233     int component;
1234     RLTable *rl = &rl_mpeg1;
1235     uint8_t * const scantable= s->intra_scantable.permutated;
1236     const uint16_t *quant_matrix= s->intra_matrix;
1237     const int qscale= s->qscale;
1238
1239     /* DC coef */
1240     component = (n <= 3 ? 0 : n - 4 + 1);
1241     diff = decode_dc(s, component);
1242     if (diff >= 0xffff)
1243         return -1;
1244     dc = s->last_dc[component];
1245     dc += diff;
1246     s->last_dc[component] = dc;
1247     block[0] = dc<<3;
1248     dprintf("dc=%d diff=%d\n", dc, diff);
1249     i = 0;
1250     {
1251         OPEN_READER(re, &s->gb);
1252         /* now quantify & encode AC coefs */
1253         for(;;) {
1254             UPDATE_CACHE(re, &s->gb);
1255             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1256
1257             if(level == 127){
1258                 break;
1259             } else if(level != 0) {
1260                 i += run;
1261                 j = scantable[i];
1262                 level= (level*qscale*quant_matrix[j])>>3;
1263                 level= (level-1)|1;
1264                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1265                 LAST_SKIP_BITS(re, &s->gb, 1);
1266             } else {
1267                 /* escape */
1268                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1269                 UPDATE_CACHE(re, &s->gb);
1270                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1271                 if (level == -128) {
1272                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1273                 } else if (level == 0) {
1274                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1275                 }
1276                 i += run;
1277                 j = scantable[i];
1278                 if(level<0){
1279                     level= -level;
1280                     level= (level*qscale*quant_matrix[j])>>3;
1281                     level= (level-1)|1;
1282                     level= -level;
1283                 }else{
1284                     level= (level*qscale*quant_matrix[j])>>3;
1285                     level= (level-1)|1;
1286                 }
1287             }
1288             if (i > 63){
1289                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1290                 return -1;
1291             }
1292
1293             block[j] = level;
1294         }
1295         CLOSE_READER(re, &s->gb);
1296     }
1297     s->block_last_index[n] = i;
1298    return 0;
1299 }
1300
1301 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
1302                                DCTELEM *block,
1303                                int n)
1304 {
1305     int level, i, j, run;
1306     RLTable *rl = &rl_mpeg1;
1307     uint8_t * const scantable= s->intra_scantable.permutated;
1308     const uint16_t *quant_matrix= s->inter_matrix;
1309     const int qscale= s->qscale;
1310
1311     {
1312         int v;
1313         OPEN_READER(re, &s->gb);
1314         i = -1;
1315         /* special case for the first coef. no need to add a second vlc table */
1316         UPDATE_CACHE(re, &s->gb);
1317         v= SHOW_UBITS(re, &s->gb, 2);
1318         if (v & 2) {
1319             LAST_SKIP_BITS(re, &s->gb, 2);
1320             level= (3*qscale*quant_matrix[0])>>4;
1321             level= (level-1)|1;
1322             if(v&1)
1323                 level= -level;
1324             block[0] = level;
1325             i++;
1326         }
1327
1328         /* now quantify & encode AC coefs */
1329         for(;;) {
1330             UPDATE_CACHE(re, &s->gb);
1331             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1332
1333             if(level == 127){
1334                 break;
1335             } else if(level != 0) {
1336                 i += run;
1337                 j = scantable[i];
1338                 level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1339                 level= (level-1)|1;
1340                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1341                 LAST_SKIP_BITS(re, &s->gb, 1);
1342             } else {
1343                 /* escape */
1344                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1345                 UPDATE_CACHE(re, &s->gb);
1346                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1347                 if (level == -128) {
1348                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1349                 } else if (level == 0) {
1350                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1351                 }
1352                 i += run;
1353                 j = scantable[i];
1354                 if(level<0){
1355                     level= -level;
1356                     level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1357                     level= (level-1)|1;
1358                     level= -level;
1359                 }else{
1360                     level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1361                     level= (level-1)|1;
1362                 }
1363             }
1364             if (i > 63){
1365                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1366                 return -1;
1367             }
1368
1369             block[j] = level;
1370         }
1371         CLOSE_READER(re, &s->gb);
1372     }
1373     s->block_last_index[n] = i;
1374     return 0;
1375 }
1376
1377 /* Also does unquantization here, since I will never support mpeg2
1378    encoding */
1379 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
1380                                DCTELEM *block,
1381                                int n)
1382 {
1383     int level, i, j, run;
1384     RLTable *rl = &rl_mpeg1;
1385     uint8_t * const scantable= s->intra_scantable.permutated;
1386     const uint16_t *quant_matrix;
1387     const int qscale= s->qscale;
1388     int mismatch;
1389
1390     mismatch = 1;
1391
1392     {
1393         int v;
1394         OPEN_READER(re, &s->gb);
1395         i = -1;
1396         if (n < 4)
1397             quant_matrix = s->inter_matrix;
1398         else
1399             quant_matrix = s->chroma_inter_matrix;
1400
1401         /* special case for the first coef. no need to add a second vlc table */
1402         UPDATE_CACHE(re, &s->gb);
1403         v= SHOW_UBITS(re, &s->gb, 2);
1404         if (v & 2) {
1405             LAST_SKIP_BITS(re, &s->gb, 2);
1406             level= (3*qscale*quant_matrix[0])>>5;
1407             if(v&1)
1408                 level= -level;
1409             block[0] = level;
1410             mismatch ^= level;
1411             i++;
1412         }
1413
1414         /* now quantify & encode AC coefs */
1415         for(;;) {
1416             UPDATE_CACHE(re, &s->gb);
1417             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1418
1419             if(level == 127){
1420                 break;
1421             } else if(level != 0) {
1422                 i += run;
1423                 j = scantable[i];
1424                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1425                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1426                 LAST_SKIP_BITS(re, &s->gb, 1);
1427             } else {
1428                 /* escape */
1429                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1430                 UPDATE_CACHE(re, &s->gb);
1431                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1432
1433                 i += run;
1434                 j = scantable[i];
1435                 if(level<0){
1436                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
1437                     level= -level;
1438                 }else{
1439                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1440                 }
1441             }
1442             if (i > 63){
1443                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1444                 return -1;
1445             }
1446
1447             mismatch ^= level;
1448             block[j] = level;
1449         }
1450         CLOSE_READER(re, &s->gb);
1451     }
1452     block[63] ^= (mismatch & 1);
1453
1454     s->block_last_index[n] = i;
1455     return 0;
1456 }
1457
1458 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1459                                DCTELEM *block,
1460                                int n)
1461 {
1462     int level, dc, diff, i, j, run;
1463     int component;
1464     RLTable *rl;
1465     uint8_t * const scantable= s->intra_scantable.permutated;
1466     const uint16_t *quant_matrix;
1467     const int qscale= s->qscale;
1468     int mismatch;
1469
1470     /* DC coef */
1471     if (n < 4){
1472         quant_matrix = s->intra_matrix;
1473         component = 0;
1474     }else{
1475         quant_matrix = s->chroma_intra_matrix;
1476         component = n - 3;
1477     }
1478     diff = decode_dc(s, component);
1479     if (diff >= 0xffff)
1480         return -1;
1481     dc = s->last_dc[component];
1482     dc += diff;
1483     s->last_dc[component] = dc;
1484     block[0] = dc << (3 - s->intra_dc_precision);
1485     dprintf("dc=%d\n", block[0]);
1486     mismatch = block[0] ^ 1;
1487     i = 0;
1488     if (s->intra_vlc_format)
1489         rl = &rl_mpeg2;
1490     else
1491         rl = &rl_mpeg1;
1492
1493     {
1494         OPEN_READER(re, &s->gb);
1495         /* now quantify & encode AC coefs */
1496         for(;;) {
1497             UPDATE_CACHE(re, &s->gb);
1498             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1499
1500             if(level == 127){
1501                 break;
1502             } else if(level != 0) {
1503                 i += run;
1504                 j = scantable[i];
1505                 level= (level*qscale*quant_matrix[j])>>4;
1506                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1507                 LAST_SKIP_BITS(re, &s->gb, 1);
1508             } else {
1509                 /* escape */
1510                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1511                 UPDATE_CACHE(re, &s->gb);
1512                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1513                 i += run;
1514                 j = scantable[i];
1515                 if(level<0){
1516                     level= (-level*qscale*quant_matrix[j])>>4;
1517                     level= -level;
1518                 }else{
1519                     level= (level*qscale*quant_matrix[j])>>4;
1520                 }
1521             }
1522             if (i > 63){
1523                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1524                 return -1;
1525             }
1526
1527             mismatch^= level;
1528             block[j] = level;
1529         }
1530         CLOSE_READER(re, &s->gb);
1531     }
1532     block[63]^= mismatch&1;
1533
1534     s->block_last_index[n] = i;
1535     return 0;
1536 }
1537
1538 typedef struct Mpeg1Context {
1539     MpegEncContext mpeg_enc_ctx;
1540     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1541     int repeat_field; /* true if we must repeat the field */
1542 } Mpeg1Context;
1543
1544 static int mpeg_decode_init(AVCodecContext *avctx)
1545 {
1546     Mpeg1Context *s = avctx->priv_data;
1547
1548     s->mpeg_enc_ctx.flags= avctx->flags;
1549     common_init(&s->mpeg_enc_ctx);
1550     init_vlcs(&s->mpeg_enc_ctx);
1551
1552     s->mpeg_enc_ctx_allocated = 0;
1553     s->mpeg_enc_ctx.picture_number = 0;
1554     s->repeat_field = 0;
1555     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1556     return 0;
1557 }
1558
1559 /* return the 8 bit start code value and update the search
1560    state. Return -1 if no start code found */
1561 static int find_start_code(uint8_t **pbuf_ptr, uint8_t *buf_end)
1562 {
1563     uint8_t *buf_ptr;
1564     unsigned int state=0xFFFFFFFF, v;
1565     int val;
1566
1567     buf_ptr = *pbuf_ptr;
1568     while (buf_ptr < buf_end) {
1569         v = *buf_ptr++;
1570         if (state == 0x000001) {
1571             state = ((state << 8) | v) & 0xffffff;
1572             val = state;
1573             goto found;
1574         }
1575         state = ((state << 8) | v) & 0xffffff;
1576     }
1577     val = -1;
1578  found:
1579     *pbuf_ptr = buf_ptr;
1580     return val;
1581 }
1582
1583 static int mpeg1_decode_picture(AVCodecContext *avctx,
1584                                 uint8_t *buf, int buf_size)
1585 {
1586     Mpeg1Context *s1 = avctx->priv_data;
1587     MpegEncContext *s = &s1->mpeg_enc_ctx;
1588     int ref, f_code;
1589
1590     init_get_bits(&s->gb, buf, buf_size*8);
1591
1592     ref = get_bits(&s->gb, 10); /* temporal ref */
1593     s->pict_type = get_bits(&s->gb, 3);
1594     dprintf("pict_type=%d number=%d\n", s->pict_type, s->picture_number);
1595
1596     skip_bits(&s->gb, 16);
1597     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
1598         s->full_pel[0] = get_bits1(&s->gb);
1599         f_code = get_bits(&s->gb, 3);
1600         if (f_code == 0)
1601             return -1;
1602         s->mpeg_f_code[0][0] = f_code;
1603         s->mpeg_f_code[0][1] = f_code;
1604     }
1605     if (s->pict_type == B_TYPE) {
1606         s->full_pel[1] = get_bits1(&s->gb);
1607         f_code = get_bits(&s->gb, 3);
1608         if (f_code == 0)
1609             return -1;
1610         s->mpeg_f_code[1][0] = f_code;
1611         s->mpeg_f_code[1][1] = f_code;
1612     }
1613     s->current_picture.pict_type= s->pict_type;
1614     s->current_picture.key_frame= s->pict_type == I_TYPE;
1615
1616     s->y_dc_scale = 8;
1617     s->c_dc_scale = 8;
1618     s->first_slice = 1;
1619     return 0;
1620 }
1621
1622 static void mpeg_decode_sequence_extension(MpegEncContext *s)
1623 {
1624     int horiz_size_ext, vert_size_ext;
1625     int bit_rate_ext, vbv_buf_ext;
1626     int frame_rate_ext_n, frame_rate_ext_d;
1627     float aspect;
1628
1629     skip_bits(&s->gb, 8); /* profil and level */
1630     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1631     skip_bits(&s->gb, 2); /* chroma_format */
1632     horiz_size_ext = get_bits(&s->gb, 2);
1633     vert_size_ext = get_bits(&s->gb, 2);
1634     s->width |= (horiz_size_ext << 12);
1635     s->height |= (vert_size_ext << 12);
1636     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1637     s->bit_rate = ((s->bit_rate / 400) | (bit_rate_ext << 12)) * 400;
1638     skip_bits1(&s->gb); /* marker */
1639     vbv_buf_ext = get_bits(&s->gb, 8);
1640     s->low_delay = get_bits1(&s->gb);
1641     frame_rate_ext_n = get_bits(&s->gb, 2);
1642     frame_rate_ext_d = get_bits(&s->gb, 5);
1643     av_reduce(
1644         &s->avctx->frame_rate,
1645         &s->avctx->frame_rate_base,
1646         frame_rate_tab[s->frame_rate_index] * (frame_rate_ext_n+1),
1647         MPEG1_FRAME_RATE_BASE * (frame_rate_ext_d+1),
1648         1<<30);
1649
1650     dprintf("sequence extension\n");
1651     s->mpeg2 = 1;
1652     s->avctx->sub_id = 2; /* indicates mpeg2 found */
1653
1654     aspect= mpeg2_aspect[s->aspect_ratio_info];
1655     if(aspect>0.0)      s->avctx->aspect_ratio= s->width/(aspect*s->height);
1656     else if(aspect<0.0) s->avctx->aspect_ratio= -1.0/aspect;
1657 }
1658
1659 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1660 {
1661     int i, v, j;
1662
1663     dprintf("matrix extension\n");
1664
1665     if (get_bits1(&s->gb)) {
1666         for(i=0;i<64;i++) {
1667             v = get_bits(&s->gb, 8);
1668             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1669             s->intra_matrix[j] = v;
1670             s->chroma_intra_matrix[j] = v;
1671         }
1672     }
1673     if (get_bits1(&s->gb)) {
1674         for(i=0;i<64;i++) {
1675             v = get_bits(&s->gb, 8);
1676             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1677             s->inter_matrix[j] = v;
1678             s->chroma_inter_matrix[j] = v;
1679         }
1680     }
1681     if (get_bits1(&s->gb)) {
1682         for(i=0;i<64;i++) {
1683             v = get_bits(&s->gb, 8);
1684             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1685             s->chroma_intra_matrix[j] = v;
1686         }
1687     }
1688     if (get_bits1(&s->gb)) {
1689         for(i=0;i<64;i++) {
1690             v = get_bits(&s->gb, 8);
1691             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1692             s->chroma_inter_matrix[j] = v;
1693         }
1694     }
1695 }
1696
1697 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1698 {
1699     s->full_pel[0] = s->full_pel[1] = 0;
1700     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1701     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1702     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1703     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1704     s->intra_dc_precision = get_bits(&s->gb, 2);
1705     s->picture_structure = get_bits(&s->gb, 2);
1706     s->top_field_first = get_bits1(&s->gb);
1707     s->frame_pred_frame_dct = get_bits1(&s->gb);
1708     s->concealment_motion_vectors = get_bits1(&s->gb);
1709     s->q_scale_type = get_bits1(&s->gb);
1710     s->intra_vlc_format = get_bits1(&s->gb);
1711     s->alternate_scan = get_bits1(&s->gb);
1712     s->repeat_first_field = get_bits1(&s->gb);
1713     s->chroma_420_type = get_bits1(&s->gb);
1714     s->progressive_frame = get_bits1(&s->gb);
1715
1716     if(s->picture_structure == PICT_FRAME)
1717         s->first_field=0;
1718     else{
1719         s->first_field ^= 1;
1720         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1721     }
1722
1723     if(s->alternate_scan){
1724         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1725         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1726         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
1727         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
1728     }else{
1729         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1730         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1731         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
1732         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
1733     }
1734
1735     /* composite display not parsed */
1736     dprintf("intra_dc_precision=%d\n", s->intra_dc_precision);
1737     dprintf("picture_structure=%d\n", s->picture_structure);
1738     dprintf("top field first=%d\n", s->top_field_first);
1739     dprintf("repeat first field=%d\n", s->repeat_first_field);
1740     dprintf("conceal=%d\n", s->concealment_motion_vectors);
1741     dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
1742     dprintf("alternate_scan=%d\n", s->alternate_scan);
1743     dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1744     dprintf("progressive_frame=%d\n", s->progressive_frame);
1745 }
1746
1747 static void mpeg_decode_extension(AVCodecContext *avctx,
1748                                   uint8_t *buf, int buf_size)
1749 {
1750     Mpeg1Context *s1 = avctx->priv_data;
1751     MpegEncContext *s = &s1->mpeg_enc_ctx;
1752     int ext_type;
1753
1754     init_get_bits(&s->gb, buf, buf_size*8);
1755
1756     ext_type = get_bits(&s->gb, 4);
1757     switch(ext_type) {
1758     case 0x1:
1759         /* sequence ext */
1760         mpeg_decode_sequence_extension(s);
1761         break;
1762     case 0x3:
1763         /* quant matrix extension */
1764         mpeg_decode_quant_matrix_extension(s);
1765         break;
1766     case 0x8:
1767         /* picture extension */
1768         mpeg_decode_picture_coding_extension(s);
1769         break;
1770     }
1771 }
1772
1773 #define DECODE_SLICE_FATAL_ERROR -2
1774 #define DECODE_SLICE_ERROR -1
1775 #define DECODE_SLICE_OK 0
1776
1777 /**
1778  * decodes a slice.
1779  * @return DECODE_SLICE_FATAL_ERROR if a non recoverable error occured<br>
1780  *         DECODE_SLICE_ERROR if the slice is damaged<br>
1781  *         DECODE_SLICE_OK if this slice is ok<br>
1782  */
1783 static int mpeg_decode_slice(AVCodecContext *avctx,
1784                               AVFrame *pict,
1785                               int start_code,
1786                               uint8_t **buf, int buf_size)
1787 {
1788     Mpeg1Context *s1 = avctx->priv_data;
1789     MpegEncContext *s = &s1->mpeg_enc_ctx;
1790     int ret;
1791     const int field_pic= s->picture_structure != PICT_FRAME;
1792
1793     s->resync_mb_x= s->mb_x =
1794     s->resync_mb_y= s->mb_y = -1;
1795
1796     start_code = (start_code - 1) & 0xff;
1797     if (start_code >= s->mb_height){
1798         fprintf(stderr, "slice below image (%d >= %d)\n", start_code, s->mb_height);
1799         return -1;
1800     }
1801
1802     ff_mpeg1_clean_buffers(s);
1803     s->interlaced_dct = 0;
1804
1805     /* start frame decoding */
1806     if (s->first_slice) {
1807       if(s->first_field || s->picture_structure==PICT_FRAME){
1808         if(MPV_frame_start(s, avctx) < 0)
1809             return DECODE_SLICE_FATAL_ERROR;
1810
1811         ff_er_frame_start(s);
1812
1813         /* first check if we must repeat the frame */
1814         s->current_picture.repeat_pict = 0;
1815
1816         if (s->repeat_first_field) {
1817             if (s->progressive_sequence) {
1818                 if (s->top_field_first)
1819                     s->current_picture.repeat_pict = 4;
1820                 else
1821                     s->current_picture.repeat_pict = 2;
1822             } else if (s->progressive_frame) {
1823                 s->current_picture.repeat_pict = 1;
1824             }
1825         }
1826 //        printf("%d \n", s->current_picture.repeat_pict);
1827
1828         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1829              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",
1830                  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],
1831                  s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")),
1832                  s->progressive_sequence ? "pro" :"", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1833                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1834                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1835         }
1836       }else{ //second field
1837             int i;
1838
1839             if(!s->current_picture_ptr){
1840                 fprintf(stderr, "first field missing\n");
1841                 return -1;
1842             }
1843
1844             for(i=0; i<4; i++){
1845                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1846                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1847                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1848                 }
1849             }
1850       }
1851     }
1852     s->first_slice = 0;
1853
1854     init_get_bits(&s->gb, *buf, buf_size*8);
1855
1856     s->qscale = get_qscale(s);
1857     if(s->qscale == 0){
1858         fprintf(stderr, "qscale == 0\n");
1859         return -1;
1860     }
1861
1862     /* extra slice info */
1863     while (get_bits1(&s->gb) != 0) {
1864         skip_bits(&s->gb, 8);
1865     }
1866
1867     s->mb_x=0;
1868
1869     for(;;) {
1870         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1871         if (code < 0){
1872             fprintf(stderr, "first mb_incr damaged\n");
1873             return -1;
1874         }
1875         if (code >= 33) {
1876             if (code == 33) {
1877                 s->mb_x += 33;
1878             }
1879             /* otherwise, stuffing, nothing to do */
1880         } else {
1881             s->mb_x += code;
1882             break;
1883         }
1884     }
1885
1886     s->resync_mb_x= s->mb_x;
1887     s->resync_mb_y= s->mb_y = start_code;
1888     s->mb_skip_run= 0;
1889
1890     for(;;) {
1891         s->dsp.clear_blocks(s->block[0]);
1892
1893         ret = mpeg_decode_mb(s, s->block);
1894
1895         dprintf("ret=%d\n", ret);
1896         if (ret < 0)
1897             return -1;
1898
1899         if(s->motion_val && s->pict_type != B_TYPE){ //note motion_val is normally NULL unless we want to extract the MVs
1900             const int wrap = s->block_wrap[0];
1901             const int xy = s->mb_x*2 + 1 + (s->mb_y*2 +1)*wrap;
1902             int motion_x, motion_y;
1903
1904             if (s->mb_intra) {
1905                 motion_x = motion_y = 0;
1906             }else if (s->mv_type == MV_TYPE_16X16) {
1907                 motion_x = s->mv[0][0][0];
1908                 motion_y = s->mv[0][0][1];
1909             } else /*if (s->mv_type == MV_TYPE_FIELD)*/ {
1910                 motion_x = s->mv[0][0][0] + s->mv[0][1][0];
1911                 motion_y = s->mv[0][0][1] + s->mv[0][1][1];
1912                 motion_x = (motion_x>>1) | (motion_x&1);
1913             }
1914             s->motion_val[xy][0] = motion_x;
1915             s->motion_val[xy][1] = motion_y;
1916             s->motion_val[xy + 1][0] = motion_x;
1917             s->motion_val[xy + 1][1] = motion_y;
1918             s->motion_val[xy + wrap][0] = motion_x;
1919             s->motion_val[xy + wrap][1] = motion_y;
1920             s->motion_val[xy + 1 + wrap][0] = motion_x;
1921             s->motion_val[xy + 1 + wrap][1] = motion_y;
1922         }
1923
1924         MPV_decode_mb(s, s->block);
1925
1926         if (++s->mb_x >= s->mb_width) {
1927             if(s->picture_structure==PICT_FRAME){
1928                 ff_draw_horiz_band(s, 16*s->mb_y, 16);
1929             }else{
1930                 if(!s->first_field){
1931                     ff_draw_horiz_band(s, 32*s->mb_y, 32);
1932                 }
1933             }
1934
1935             s->mb_x = 0;
1936             s->mb_y++;
1937
1938             if(s->mb_y<<field_pic >= s->mb_height){
1939                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1940
1941                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)))
1942                    || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
1943                     fprintf(stderr, "end missmatch left=%d\n", left);
1944                     return -1;
1945                 }else
1946                     goto eos;
1947             }
1948         }
1949
1950         /* skip mb handling */
1951         if (s->mb_skip_run == -1) {
1952             /* read again increment */
1953             s->mb_skip_run = 0;
1954             for(;;) {
1955                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1956                 if (code < 0){
1957                     fprintf(stderr, "mb incr damaged\n");
1958                     return -1;
1959                 }
1960                 if (code >= 33) {
1961                     if (code == 33) {
1962                         s->mb_skip_run += 33;
1963                     }else if(code == 35){
1964                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1965                             fprintf(stderr, "slice missmatch\n");
1966                             return -1;
1967                         }
1968                         goto eos; /* end of slice */
1969                     }
1970                     /* otherwise, stuffing, nothing to do */
1971                 } else {
1972                     s->mb_skip_run += code;
1973                     break;
1974                 }
1975             }
1976         }
1977     }
1978 eos: // end of slice
1979     *buf += get_bits_count(&s->gb)/8 - 1;
1980 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1981     return 0;
1982 }
1983
1984 /**
1985  * handles slice ends.
1986  * @return 1 if it seems to be the last slice of
1987  */
1988 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1989 {
1990     Mpeg1Context *s1 = avctx->priv_data;
1991     MpegEncContext *s = &s1->mpeg_enc_ctx;
1992
1993     /* end of slice reached */
1994     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1995         /* end of image */
1996
1997         if(s->mpeg2){
1998             s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1999         }else
2000             s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG1;
2001
2002         ff_er_frame_end(s);
2003
2004         MPV_frame_end(s);
2005
2006         if (s->pict_type == B_TYPE || s->low_delay) {
2007             *pict= *(AVFrame*)&s->current_picture;
2008             ff_print_debug_info(s, s->current_picture_ptr);
2009         } else {
2010             s->picture_number++;
2011             /* latency of 1 frame for I and P frames */
2012             /* XXX: use another variable than picture_number */
2013             if (s->last_picture_ptr != NULL) {
2014                 *pict= *(AVFrame*)&s->last_picture;
2015                  ff_print_debug_info(s, s->last_picture_ptr);
2016             }
2017         }
2018         return 1;
2019     } else {
2020         return 0;
2021     }
2022 }
2023
2024 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2025                                  uint8_t *buf, int buf_size)
2026 {
2027     Mpeg1Context *s1 = avctx->priv_data;
2028     MpegEncContext *s = &s1->mpeg_enc_ctx;
2029     int width, height, i, v, j;
2030     float aspect;
2031
2032     init_get_bits(&s->gb, buf, buf_size*8);
2033
2034     width = get_bits(&s->gb, 12);
2035     height = get_bits(&s->gb, 12);
2036     s->aspect_ratio_info= get_bits(&s->gb, 4);
2037     if(!s->mpeg2){
2038         aspect= mpeg1_aspect[s->aspect_ratio_info];
2039         if(aspect!=0.0) avctx->aspect_ratio= width/(aspect*height);
2040     }
2041
2042     s->frame_rate_index = get_bits(&s->gb, 4);
2043     if (s->frame_rate_index == 0)
2044         return -1;
2045     s->bit_rate = get_bits(&s->gb, 18) * 400;
2046     if (get_bits1(&s->gb) == 0) /* marker */
2047         return -1;
2048     if (width <= 0 || height <= 0 ||
2049         (width % 2) != 0 || (height % 2) != 0)
2050         return -1;
2051     if (width != s->width ||
2052         height != s->height) {
2053         /* start new mpeg1 context decoding */
2054         s->out_format = FMT_MPEG1;
2055         if (s1->mpeg_enc_ctx_allocated) {
2056             MPV_common_end(s);
2057         }
2058         s->width = width;
2059         s->height = height;
2060         avctx->has_b_frames= 1;
2061         s->avctx = avctx;
2062         avctx->width = width;
2063         avctx->height = height;
2064         av_reduce(
2065             &avctx->frame_rate,
2066             &avctx->frame_rate_base,
2067             frame_rate_tab[s->frame_rate_index],
2068             MPEG1_FRAME_RATE_BASE, //FIXME store in allready reduced form
2069             1<<30
2070             );
2071         avctx->bit_rate = s->bit_rate;
2072
2073         if (MPV_common_init(s) < 0)
2074             return -1;
2075         s1->mpeg_enc_ctx_allocated = 1;
2076     }
2077
2078     skip_bits(&s->gb, 10); /* vbv_buffer_size */
2079     skip_bits(&s->gb, 1);
2080
2081     /* get matrix */
2082     if (get_bits1(&s->gb)) {
2083         for(i=0;i<64;i++) {
2084             v = get_bits(&s->gb, 8);
2085             j = s->intra_scantable.permutated[i];
2086             s->intra_matrix[j] = v;
2087             s->chroma_intra_matrix[j] = v;
2088         }
2089 #ifdef DEBUG
2090         dprintf("intra matrix present\n");
2091         for(i=0;i<64;i++)
2092             dprintf(" %d", s->intra_matrix[s->intra_scantable.permutated[i]]);
2093         printf("\n");
2094 #endif
2095     } else {
2096         for(i=0;i<64;i++) {
2097             int j= s->dsp.idct_permutation[i];
2098             v = ff_mpeg1_default_intra_matrix[i];
2099             s->intra_matrix[j] = v;
2100             s->chroma_intra_matrix[j] = v;
2101         }
2102     }
2103     if (get_bits1(&s->gb)) {
2104         for(i=0;i<64;i++) {
2105             v = get_bits(&s->gb, 8);
2106             j = s->intra_scantable.permutated[i];
2107             s->inter_matrix[j] = v;
2108             s->chroma_inter_matrix[j] = v;
2109         }
2110 #ifdef DEBUG
2111         dprintf("non intra matrix present\n");
2112         for(i=0;i<64;i++)
2113             dprintf(" %d", s->inter_matrix[s->intra_scantable.permutated[i]]);
2114         printf("\n");
2115 #endif
2116     } else {
2117         for(i=0;i<64;i++) {
2118             int j= s->dsp.idct_permutation[i];
2119             v = ff_mpeg1_default_non_intra_matrix[i];
2120             s->inter_matrix[j] = v;
2121             s->chroma_inter_matrix[j] = v;
2122         }
2123     }
2124
2125     /* we set mpeg2 parameters so that it emulates mpeg1 */
2126     s->progressive_sequence = 1;
2127     s->progressive_frame = 1;
2128     s->picture_structure = PICT_FRAME;
2129     s->frame_pred_frame_dct = 1;
2130     s->mpeg2 = 0;
2131     avctx->sub_id = 1; /* indicates mpeg1 */
2132     return 0;
2133 }
2134
2135 static void mpeg_decode_user_data(AVCodecContext *avctx,
2136                                   const uint8_t *buf, int buf_size)
2137 {
2138     const uint8_t *p;
2139     int len, flags;
2140     p = buf;
2141     len = buf_size;
2142
2143     /* we parse the DTG active format information */
2144     if (len >= 5 &&
2145         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2146         flags = p[4];
2147         p += 5;
2148         len -= 5;
2149         if (flags & 0x80) {
2150             /* skip event id */
2151             if (len < 2)
2152                 return;
2153             p += 2;
2154             len -= 2;
2155         }
2156         if (flags & 0x40) {
2157             if (len < 1)
2158                 return;
2159             avctx->dtg_active_format = p[0] & 0x0f;
2160         }
2161     }
2162 }
2163
2164 /**
2165  * finds the end of the current frame in the bitstream.
2166  * @return the position of the first byte of the next frame, or -1
2167  */
2168 static int mpeg1_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
2169     ParseContext *pc= &s->parse_context;
2170     int i;
2171     uint32_t state;
2172
2173     state= pc->state;
2174
2175     i=0;
2176     if(!pc->frame_start_found){
2177         for(i=0; i<buf_size; i++){
2178             state= (state<<8) | buf[i];
2179             if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2180                 i++;
2181                 pc->frame_start_found=1;
2182                 break;
2183             }
2184         }
2185     }
2186
2187     if(pc->frame_start_found){
2188         for(; i<buf_size; i++){
2189             state= (state<<8) | buf[i];
2190             if((state&0xFFFFFF00) == 0x100){
2191                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2192                     pc->frame_start_found=0;
2193                     pc->state=-1;
2194                     return i-3;
2195                 }
2196             }
2197         }
2198     }
2199     pc->state= state;
2200     return END_NOT_FOUND;
2201 }
2202
2203 /* handle buffering and image synchronisation */
2204 static int mpeg_decode_frame(AVCodecContext *avctx,
2205                              void *data, int *data_size,
2206                              uint8_t *buf, int buf_size)
2207 {
2208     Mpeg1Context *s = avctx->priv_data;
2209     uint8_t *buf_end, *buf_ptr;
2210     int ret, start_code, input_size;
2211     AVFrame *picture = data;
2212     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2213     dprintf("fill_buffer\n");
2214
2215     *data_size = 0;
2216
2217     /* special case for last picture */
2218     if (buf_size == 0) {
2219         if (s2->picture_number > 0) {
2220             *picture= *(AVFrame*)&s2->next_picture;
2221
2222             *data_size = sizeof(AVFrame);
2223         }
2224         return 0;
2225     }
2226
2227     if(s2->flags&CODEC_FLAG_TRUNCATED){
2228         int next= mpeg1_find_frame_end(s2, buf, buf_size);
2229
2230         if( ff_combine_frame(s2, next, &buf, &buf_size) < 0 )
2231             return buf_size;
2232     }
2233
2234     buf_ptr = buf;
2235     buf_end = buf + buf_size;
2236
2237 #if 0
2238     if (s->repeat_field % 2 == 1) {
2239         s->repeat_field++;
2240         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2241         //        s2->picture_number, s->repeat_field);
2242         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2243             *data_size = sizeof(AVPicture);
2244             goto the_end;
2245         }
2246     }
2247 #endif
2248     for(;;) {
2249         /* find start next code */
2250         start_code = find_start_code(&buf_ptr, buf_end);
2251         if (start_code < 0){
2252             if (slice_end(avctx, picture)) {
2253                 if(s2->last_picture_ptr) //FIXME merge with the stuff in mpeg_decode_slice
2254                     *data_size = sizeof(AVPicture);
2255             }
2256             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2257         }
2258
2259         input_size = buf_end - buf_ptr;
2260
2261         if(avctx->debug & FF_DEBUG_STARTCODE){
2262             printf("%3X at %d left %d\n", start_code, buf_ptr-buf, input_size);
2263         }
2264
2265                 /* prepare data for next start code */
2266                 switch(start_code) {
2267                 case SEQ_START_CODE:
2268                     mpeg1_decode_sequence(avctx, buf_ptr,
2269                                           input_size);
2270                     break;
2271
2272                 case PICTURE_START_CODE:
2273                     /* we have a complete image : we try to decompress it */
2274                     mpeg1_decode_picture(avctx,
2275                                          buf_ptr, input_size);
2276                     break;
2277                 case EXT_START_CODE:
2278                     mpeg_decode_extension(avctx,
2279                                           buf_ptr, input_size);
2280                     break;
2281                 case USER_START_CODE:
2282                     mpeg_decode_user_data(avctx,
2283                                           buf_ptr, input_size);
2284                     break;
2285                 default:
2286                     if (start_code >= SLICE_MIN_START_CODE &&
2287                         start_code <= SLICE_MAX_START_CODE) {
2288
2289                         /* skip b frames if we dont have reference frames */
2290                         if(s2->last_picture_ptr==NULL && s2->pict_type==B_TYPE) break;
2291                         /* skip b frames if we are in a hurry */
2292                         if(avctx->hurry_up && s2->pict_type==B_TYPE) break;
2293                         /* skip everything if we are in a hurry>=5 */
2294                         if(avctx->hurry_up>=5) break;
2295
2296                         if (!s->mpeg_enc_ctx_allocated) break;
2297
2298                         ret = mpeg_decode_slice(avctx, picture,
2299                                                 start_code, &buf_ptr, input_size);
2300                         emms_c();
2301
2302                         if(ret < 0){
2303                             if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2304                                 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);
2305                             if(ret==DECODE_SLICE_FATAL_ERROR) return -1;
2306                         }else{
2307                             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);
2308                         }
2309                     }
2310                     break;
2311                 }
2312     }
2313 }
2314
2315 static int mpeg_decode_end(AVCodecContext *avctx)
2316 {
2317     Mpeg1Context *s = avctx->priv_data;
2318
2319     if (s->mpeg_enc_ctx_allocated)
2320         MPV_common_end(&s->mpeg_enc_ctx);
2321     return 0;
2322 }
2323
2324 AVCodec mpeg_decoder = {
2325     "mpegvideo",
2326     CODEC_TYPE_VIDEO,
2327     CODEC_ID_MPEG1VIDEO,
2328     sizeof(Mpeg1Context),
2329     mpeg_decode_init,
2330     NULL,
2331     mpeg_decode_end,
2332     mpeg_decode_frame,
2333     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
2334 };