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   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
  77 /* simple include everything table for dc, first byte is bits number next 3 are code*/
  78 static uint32_t mpeg1_lum_dc_uni[512];
  79 static uint32_t mpeg1_chr_dc_uni[512];
  80
  81 static uint8_t mpeg1_index_run[2][64];
  82 static int8_t mpeg1_max_level[2][64];
  83 #endif
  84
  85 static void init_2d_vlc_rl(RLTable *rl)
  86 {
  87     int i;
  88
  89     init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2,
  90              &rl->table_vlc[0][1], 4, 2,
  91              &rl->table_vlc[0][0], 4, 2);
  92
  93
  94     rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
  95     for(i=0; i<rl->vlc.table_size; i++){
  96         int code= rl->vlc.table[i][0];
  97         int len = rl->vlc.table[i][1];
  98         int level, run;
  99
 100         if(len==0){ // illegal code
 101             run= 65;
 102             level= MAX_LEVEL;
 103         }else if(len<0){ //more bits needed
 104             run= 0;
 105             level= code;
 106         }else{
 107             if(code==rl->n){ //esc
 108                 run= 65;
 109                 level= 0;
 110             }else if(code==rl->n+1){ //eob
 111                 run= 0;
 112                 level= 127;
 113             }else{
 114                 run=   rl->table_run  [code] + 1;
 115                 level= rl->table_level[code];
 116             }
 117         }
 118         rl->rl_vlc[0][i].len= len;
 119         rl->rl_vlc[0][i].level= level;
 120         rl->rl_vlc[0][i].run= run;
 121     }
 122 }
 123
 124 #ifdef CONFIG_ENCODERS
 125 static void init_uni_ac_vlc(RLTable *rl, uint32_t *uni_ac_vlc_bits, uint8_t *uni_ac_vlc_len){
 126     int i;
 127
 128     for(i=0; i<128; i++){
 129         int level= i-64;
 130         int run;
 131         for(run=0; run<64; run++){
 132             int len, bits, code;
 133
 134             int alevel= ABS(level);
 135             int sign= (level>>31)&1;
 136
 137             if (alevel > rl->max_level[0][run])
 138                 code= 111; /*rl->n*/
 139             else
 140                 code= rl->index_run[0][run] + alevel - 1;
 141
 142             if (code < 111 /* rl->n */) {
 143                 /* store the vlc & sign at once */
 144                 len=   mpeg1_vlc[code][1]+1;
 145                 bits= (mpeg1_vlc[code][0]<<1) + sign;
 146             } else {
 147                 len=  mpeg1_vlc[111/*rl->n*/][1]+6;
 148                 bits= mpeg1_vlc[111/*rl->n*/][0]<<6;
 149
 150                 bits|= run;
 151                 if (alevel < 128) {
 152                     bits<<=8; len+=8;
 153                     bits|= level & 0xff;
 154                 } else {
 155                     bits<<=16; len+=16;
 156                     bits|= level & 0xff;
 157                     if (level < 0) {
 158                         bits|= 0x8001 + level + 255;
 159                     } else {
 160                         bits|= level & 0xffff;
 161                     }
 162                 }
 163             }
 164
 165             uni_ac_vlc_bits[UNI_AC_ENC_INDEX(run, i)]= bits;
 166             uni_ac_vlc_len [UNI_AC_ENC_INDEX(run, i)]= len;
 167         }
 168     }
 169 }
 170
 171 static void put_header(MpegEncContext *s, int header)
 172 {
 173     align_put_bits(&s->pb);
 174     put_bits(&s->pb, 16, header>>16);
 175     put_bits(&s->pb, 16, header&0xFFFF);
 176 }
 177
 178 /* put sequence header if needed */
 179 static void mpeg1_encode_sequence_header(MpegEncContext *s)
 180 {
 181         unsigned int vbv_buffer_size;
 182         unsigned int fps, v;
 183         int n, i;
 184         uint64_t time_code;
 185         float best_aspect_error= 1E10;
 186         float aspect_ratio= s->avctx->aspect_ratio;
 187
 188         if(aspect_ratio==0.0) aspect_ratio= s->width / (float)s->height; //pixel aspect 1:1 (VGA)
 189
 190         if (s->current_picture.key_frame) {
 191             /* mpeg1 header repeated every gop */
 192             put_header(s, SEQ_START_CODE);
 193
 194             /* search closest frame rate */
 195             {
 196                 int i, dmin, d;
 197                 s->frame_rate_index = 0;
 198                 dmin = 0x7fffffff;
 199                 for(i=1;i<14;i++) {
 200                     if(s->avctx->strict_std_compliance >= 0 && i>=9) break;
 201
 202                     d = abs(MPEG1_FRAME_RATE_BASE*(int64_t)s->avctx->frame_rate/s->avctx->frame_rate_base - frame_rate_tab[i]);
 203                     if (d < dmin) {
 204                         dmin = d;
 205                         s->frame_rate_index = i;
 206                     }
 207                 }
 208             }
 209
 210             put_bits(&s->pb, 12, s->width);
 211             put_bits(&s->pb, 12, s->height);
 212
 213             for(i=1; i<15; i++){
 214                 float error= mpeg1_aspect[i] - s->width/(s->height*aspect_ratio);
 215                 error= ABS(error);
 216
 217                 if(error < best_aspect_error){
 218                     best_aspect_error= error;
 219                     s->aspect_ratio_info= i;
 220                 }
 221             }
 222
 223             put_bits(&s->pb, 4, s->aspect_ratio_info);
 224             put_bits(&s->pb, 4, s->frame_rate_index);
 225             v = (s->bit_rate + 399) / 400;
 226             if (v > 0x3ffff)
 227                 v = 0x3ffff;
 228             put_bits(&s->pb, 18, v);
 229             put_bits(&s->pb, 1, 1); /* marker */
 230
 231             if(s->avctx->rc_buffer_size)
 232                 vbv_buffer_size = s->avctx->rc_buffer_size;
 233             else
 234                 /* VBV calculation: Scaled so that a VCD has the proper VBV size of 40 kilobytes */
 235                 vbv_buffer_size = (( 20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024;
 236             put_bits(&s->pb, 10, (vbv_buffer_size + 16383) / 16384);
 237             put_bits(&s->pb, 1, 1); /* constrained parameter flag */
 238             put_bits(&s->pb, 1, 0); /* no custom intra matrix */
 239             put_bits(&s->pb, 1, 0); /* no custom non intra matrix */
 240
 241             put_header(s, GOP_START_CODE);
 242             put_bits(&s->pb, 1, 0); /* do drop frame */
 243             /* time code : we must convert from the real frame rate to a
 244                fake mpeg frame rate in case of low frame rate */
 245             fps = frame_rate_tab[s->frame_rate_index];
 246             time_code = (int64_t)s->fake_picture_number * MPEG1_FRAME_RATE_BASE;
 247             s->gop_picture_number = s->fake_picture_number;
 248             put_bits(&s->pb, 5, (uint32_t)((time_code / (fps * 3600)) % 24));
 249             put_bits(&s->pb, 6, (uint32_t)((time_code / (fps * 60)) % 60));
 250             put_bits(&s->pb, 1, 1);
 251             put_bits(&s->pb, 6, (uint32_t)((time_code / fps) % 60));
 252             put_bits(&s->pb, 6, (uint32_t)((time_code % fps) / MPEG1_FRAME_RATE_BASE));
 253             put_bits(&s->pb, 1, 1); /* closed gop */
 254             put_bits(&s->pb, 1, 0); /* broken link */
 255         }
 256
 257         if (s->avctx->frame_rate < (24 * s->avctx->frame_rate_base) && s->picture_number > 0) {
 258             /* insert empty P pictures to slow down to the desired
 259                frame rate. Each fake pictures takes about 20 bytes */
 260             fps = frame_rate_tab[s->frame_rate_index];
 261             n = av_rescale((int64_t)s->picture_number * s->avctx->frame_rate_base, fps, s->avctx->frame_rate) / MPEG1_FRAME_RATE_BASE - 1;
 262             while (s->fake_picture_number < n) {
 263                 mpeg1_skip_picture(s, s->fake_picture_number -
 264                                    s->gop_picture_number);
 265                 s->fake_picture_number++;
 266             }
 267
 268         }
 269 }
 270
 271 static inline void encode_mb_skip_run(MpegEncContext *s, int run){
 272     while (run >= 33) {
 273         put_bits(&s->pb, 11, 0x008);
 274         run -= 33;
 275     }
 276     put_bits(&s->pb, mbAddrIncrTable[run][1],
 277              mbAddrIncrTable[run][0]);
 278 }
 279
 280 /* insert a fake P picture */
 281 static void mpeg1_skip_picture(MpegEncContext *s, int pict_num)
 282 {
 283     /* mpeg1 picture header */
 284     put_header(s, PICTURE_START_CODE);
 285     /* temporal reference */
 286     put_bits(&s->pb, 10, pict_num & 0x3ff);
 287
 288     put_bits(&s->pb, 3, P_TYPE);
 289     put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
 290
 291     put_bits(&s->pb, 1, 1); /* integer coordinates */
 292     put_bits(&s->pb, 3, 1); /* forward_f_code */
 293
 294     put_bits(&s->pb, 1, 0); /* extra bit picture */
 295
 296     /* only one slice */
 297     put_header(s, SLICE_MIN_START_CODE);
 298     put_bits(&s->pb, 5, 1); /* quantizer scale */
 299     put_bits(&s->pb, 1, 0); /* slice extra information */
 300
 301     encode_mb_skip_run(s, 0);
 302
 303     /* empty macroblock */
 304     put_bits(&s->pb, 3, 1); /* motion only */
 305
 306     /* zero motion x & y */
 307     put_bits(&s->pb, 1, 1);
 308     put_bits(&s->pb, 1, 1);
 309
 310     /* output a number of empty slice */
 311     encode_mb_skip_run(s, s->mb_width * s->mb_height - 2);
 312
 313     /* empty macroblock */
 314     put_bits(&s->pb, 3, 1); /* motion only */
 315
 316     /* zero motion x & y */
 317     put_bits(&s->pb, 1, 1);
 318     put_bits(&s->pb, 1, 1);
 319 }
 320 #endif
 321
 322 static void common_init(MpegEncContext *s)
 323 {
 324     s->y_dc_scale_table=
 325     s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
 326 }
 327
 328 void ff_mpeg1_clean_buffers(MpegEncContext *s){
 329     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
 330     s->last_dc[1] = s->last_dc[0];
 331     s->last_dc[2] = s->last_dc[0];
 332     memset(s->last_mv, 0, sizeof(s->last_mv));
 333 }
 334
 335 #ifdef CONFIG_ENCODERS
 336
 337 void ff_mpeg1_encode_slice_header(MpegEncContext *s){
 338     put_header(s, SLICE_MIN_START_CODE + s->mb_y);
 339     put_bits(&s->pb, 5, s->qscale); /* quantizer scale */
 340     put_bits(&s->pb, 1, 0); /* slice extra information */
 341 }
 342
 343 void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
 344 {
 345     mpeg1_encode_sequence_header(s);
 346
 347     /* mpeg1 picture header */
 348     put_header(s, PICTURE_START_CODE);
 349     /* temporal reference */
 350
 351     // RAL: s->picture_number instead of s->fake_picture_number
 352     put_bits(&s->pb, 10, (s->picture_number -
 353                           s->gop_picture_number) & 0x3ff);
 354     s->fake_picture_number++;
 355
 356     put_bits(&s->pb, 3, s->pict_type);
 357     put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
 358
 359     // RAL: Forward f_code also needed for B frames
 360     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
 361         put_bits(&s->pb, 1, 0); /* half pel coordinates */
 362         put_bits(&s->pb, 3, s->f_code); /* forward_f_code */
 363     }
 364
 365     // RAL: Backward f_code necessary for B frames
 366     if (s->pict_type == B_TYPE) {
 367         put_bits(&s->pb, 1, 0); /* half pel coordinates */
 368         put_bits(&s->pb, 3, s->b_code); /* backward_f_code */
 369         }
 370
 371     put_bits(&s->pb, 1, 0); /* extra bit picture */
 372
 373     s->mb_y=0;
 374     ff_mpeg1_encode_slice_header(s);
 375 }
 376
 377 void mpeg1_encode_mb(MpegEncContext *s,
 378                      DCTELEM block[6][64],
 379                      int motion_x, int motion_y)
 380 {
 381     int i, cbp;
 382     const int mb_x = s->mb_x;
 383     const int mb_y = s->mb_y;
 384     const int first_mb= mb_x == s->resync_mb_x && mb_y == s->resync_mb_y;
 385
 386     /* compute cbp */
 387     cbp = 0;
 388     for(i=0;i<6;i++) {
 389         if (s->block_last_index[i] >= 0)
 390             cbp |= 1 << (5 - i);
 391     }
 392
 393     if (cbp == 0 && !first_mb && (mb_x != s->mb_width - 1 || mb_y != s->mb_height - 1) &&
 394         ((s->pict_type == P_TYPE && (motion_x | motion_y) == 0) ||
 395         (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) |
 396         ((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))) {
 397         s->mb_skip_run++;
 398         s->qscale -= s->dquant;
 399         s->skip_count++;
 400         s->misc_bits++;
 401         s->last_bits++;
 402     } else {
 403         if(first_mb){
 404             assert(s->mb_skip_run == 0);
 405             encode_mb_skip_run(s, s->mb_x);
 406         }else{
 407             encode_mb_skip_run(s, s->mb_skip_run);
 408         }
 409
 410         if (s->pict_type == I_TYPE) {
 411             if(s->dquant && cbp){
 412                 put_bits(&s->pb, 2, 1); /* macroblock_type : macroblock_quant = 1 */
 413                 put_bits(&s->pb, 5, s->qscale);
 414             }else{
 415                 put_bits(&s->pb, 1, 1); /* macroblock_type : macroblock_quant = 0 */
 416                 s->qscale -= s->dquant;
 417             }
 418             s->misc_bits+= get_bits_diff(s);
 419             s->i_count++;
 420         } else if (s->mb_intra) {
 421             if(s->dquant && cbp){
 422                 put_bits(&s->pb, 6, 0x01);
 423                 put_bits(&s->pb, 5, s->qscale);
 424             }else{
 425                 put_bits(&s->pb, 5, 0x03);
 426                 s->qscale -= s->dquant;
 427             }
 428             s->misc_bits+= get_bits_diff(s);
 429             s->i_count++;
 430             s->last_mv[0][0][0] =
 431             s->last_mv[0][0][1] = 0;
 432         } else if (s->pict_type == P_TYPE) {
 433                 if (cbp != 0) {
 434                     if (motion_x == 0 && motion_y == 0) {
 435                         if(s->dquant){
 436                             put_bits(&s->pb, 5, 1); /* macroblock_pattern & quant */
 437                             put_bits(&s->pb, 5, s->qscale);
 438                         }else{
 439                             put_bits(&s->pb, 2, 1); /* macroblock_pattern only */
 440                         }
 441                         s->misc_bits+= get_bits_diff(s);
 442                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
 443                     } else {
 444                         if(s->dquant){
 445                             put_bits(&s->pb, 5, 2); /* motion + cbp */
 446                             put_bits(&s->pb, 5, s->qscale);
 447                         }else{
 448                             put_bits(&s->pb, 1, 1); /* motion + cbp */
 449                         }
 450                         s->misc_bits+= get_bits_diff(s);
 451                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
 452                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
 453                         s->mv_bits+= get_bits_diff(s);
 454                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
 455                     }
 456                 } else {
 457                     put_bits(&s->pb, 3, 1); /* motion only */
 458                     mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);    // RAL: f_code parameter added
 459                     mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);    // RAL: f_code parameter added
 460                     s->qscale -= s->dquant;
 461                     s->mv_bits+= get_bits_diff(s);
 462                 }
 463                 s->f_count++;
 464         } else
 465             {    // RAL: All the following bloc added for B frames:
 466                 if (cbp != 0)
 467                     {    // With coded bloc pattern
 468                     if (s->mv_dir == (MV_DIR_FORWARD | MV_DIR_BACKWARD))
 469                         {    // Bi-directional motion
 470                         if (s->dquant)
 471                             {    // With QScale
 472                             put_bits(&s->pb, 5, 2);
 473                             put_bits(&s->pb, 5, s->qscale);
 474                             }
 475                         else    // Without QScale
 476                             put_bits(&s->pb, 2, 3);
 477                         s->misc_bits += get_bits_diff(s);
 478                         mpeg1_encode_motion(s, s->mv[0][0][0] - s->last_mv[0][0][0], s->f_code);
 479                         mpeg1_encode_motion(s, s->mv[0][0][1] - s->last_mv[0][0][1], s->f_code);
 480                         mpeg1_encode_motion(s, s->mv[1][0][0] - s->last_mv[1][0][0], s->b_code);
 481                         mpeg1_encode_motion(s, s->mv[1][0][1] - s->last_mv[1][0][1], s->b_code);
 482                         s->b_count++;
 483                         s->f_count++;
 484                         s->mv_bits += get_bits_diff(s);
 485                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
 486                         }
 487                     else if (s->mv_dir == MV_DIR_BACKWARD)
 488                         {    // Backward motion
 489                         if (s->dquant)
 490                             {    // With QScale
 491                             put_bits(&s->pb, 6, 2);
 492                             put_bits(&s->pb, 5, s->qscale);
 493                             }
 494                         else    // Without QScale
 495                             put_bits(&s->pb, 3, 3);
 496                         s->misc_bits += get_bits_diff(s);
 497                         mpeg1_encode_motion(s, motion_x - s->last_mv[1][0][0], s->b_code);
 498                         mpeg1_encode_motion(s, motion_y - s->last_mv[1][0][1], s->b_code);
 499                         s->b_count++;
 500                         s->mv_bits += get_bits_diff(s);
 501                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
 502                         }
 503                     else if (s->mv_dir == MV_DIR_FORWARD)
 504                         {    // Forward motion
 505                         if (s->dquant)
 506                             {    // With QScale
 507                             put_bits(&s->pb, 6, 3);
 508                             put_bits(&s->pb, 5, s->qscale);
 509                             }
 510                         else    // Without QScale
 511                             put_bits(&s->pb, 4, 3);
 512                         s->misc_bits += get_bits_diff(s);
 513                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);
 514                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);
 515                         s->f_count++;
 516                         s->mv_bits += get_bits_diff(s);
 517                         put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
 518                         }
 519                     }
 520                 else
 521                     {    // No coded bloc pattern
 522                     if (s->mv_dir == (MV_DIR_FORWARD | MV_DIR_BACKWARD))
 523                         {    // Bi-directional motion
 524                         put_bits(&s->pb, 2, 2); /* backward & forward motion */
 525                         mpeg1_encode_motion(s, s->mv[0][0][0] - s->last_mv[0][0][0], s->f_code);
 526                         mpeg1_encode_motion(s, s->mv[0][0][1] - s->last_mv[0][0][1], s->f_code);
 527                         mpeg1_encode_motion(s, s->mv[1][0][0] - s->last_mv[1][0][0], s->b_code);
 528                         mpeg1_encode_motion(s, s->mv[1][0][1] - s->last_mv[1][0][1], s->b_code);
 529                         s->b_count++;
 530                         s->f_count++;
 531                         }
 532                     else if (s->mv_dir == MV_DIR_BACKWARD)
 533                         {    // Backward motion
 534                         put_bits(&s->pb, 3, 2); /* backward motion only */
 535                         mpeg1_encode_motion(s, motion_x - s->last_mv[1][0][0], s->b_code);
 536                         mpeg1_encode_motion(s, motion_y - s->last_mv[1][0][1], s->b_code);
 537                         s->b_count++;
 538                         }
 539                     else if (s->mv_dir == MV_DIR_FORWARD)
 540                         {    // Forward motion
 541                         put_bits(&s->pb, 4, 2); /* forward motion only */
 542                         mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0], s->f_code);
 543                         mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1], s->f_code);
 544                         s->f_count++;
 545                         }
 546                     s->qscale -= s->dquant;
 547                     s->mv_bits += get_bits_diff(s);
 548                     }
 549             // End of bloc from RAL
 550             }
 551         for(i=0;i<6;i++) {
 552             if (cbp & (1 << (5 - i))) {
 553                 mpeg1_encode_block(s, block[i], i);
 554             }
 555         }
 556         s->mb_skip_run = 0;
 557         if(s->mb_intra)
 558             s->i_tex_bits+= get_bits_diff(s);
 559         else
 560             s->p_tex_bits+= get_bits_diff(s);
 561     }
 562
 563     // RAL: By this:
 564     if (s->mv_dir & MV_DIR_FORWARD)
 565         {
 566         s->last_mv[0][0][0]= s->mv[0][0][0];
 567         s->last_mv[0][0][1]= s->mv[0][0][1];
 568         }
 569     if (s->mv_dir & MV_DIR_BACKWARD)
 570         {
 571         s->last_mv[1][0][0]= s->mv[1][0][0];
 572         s->last_mv[1][0][1]= s->mv[1][0][1];
 573         }
 574 }
 575
 576 // RAL: Parameter added: f_or_b_code
 577 static void mpeg1_encode_motion(MpegEncContext *s, int val, int f_or_b_code)
 578 {
 579     int code, bit_size, l, m, bits, range, sign;
 580
 581     if (val == 0) {
 582         /* zero vector */
 583         code = 0;
 584         put_bits(&s->pb,
 585                  mbMotionVectorTable[0][1],
 586                  mbMotionVectorTable[0][0]);
 587     } else {
 588         bit_size = f_or_b_code - 1;
 589         range = 1 << bit_size;
 590         /* modulo encoding */
 591         l = 16 * range;
 592         m = 2 * l;
 593         if (val < -l) {
 594             val += m;
 595         } else if (val >= l) {
 596             val -= m;
 597         }
 598
 599         if (val >= 0) {
 600             val--;
 601             code = (val >> bit_size) + 1;
 602             bits = val & (range - 1);
 603             sign = 0;
 604         } else {
 605             val = -val;
 606             val--;
 607             code = (val >> bit_size) + 1;
 608             bits = val & (range - 1);
 609             sign = 1;
 610         }
 611
 612         assert(code > 0 && code <= 16);
 613
 614         put_bits(&s->pb,
 615                  mbMotionVectorTable[code][1],
 616                  mbMotionVectorTable[code][0]);
 617
 618         put_bits(&s->pb, 1, sign);
 619         if (bit_size > 0) {
 620             put_bits(&s->pb, bit_size, bits);
 621         }
 622     }
 623 }
 624
 625 void ff_mpeg1_encode_init(MpegEncContext *s)
 626 {
 627     static int done=0;
 628
 629     common_init(s);
 630
 631     if(!done){
 632         int f_code;
 633         int mv;
 634         int i;
 635
 636         done=1;
 637         init_rl(&rl_mpeg1);
 638
 639         for(i=0; i<64; i++)
 640         {
 641                 mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i];
 642                 mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i];
 643         }
 644
 645         init_uni_ac_vlc(&rl_mpeg1, uni_mpeg1_ac_vlc_bits, uni_mpeg1_ac_vlc_len);
 646
 647         /* build unified dc encoding tables */
 648         for(i=-255; i<256; i++)
 649         {
 650                 int adiff, index;
 651                 int bits, code;
 652                 int diff=i;
 653
 654                 adiff = ABS(diff);
 655                 if(diff<0) diff--;
 656                 index = vlc_dc_table[adiff];
 657
 658                 bits= vlc_dc_lum_bits[index] + index;
 659                 code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1));
 660                 mpeg1_lum_dc_uni[i+255]= bits + (code<<8);
 661
 662                 bits= vlc_dc_chroma_bits[index] + index;
 663                 code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1));
 664                 mpeg1_chr_dc_uni[i+255]= bits + (code<<8);
 665         }
 666
 667         mv_penalty= av_mallocz( sizeof(uint8_t)*(MAX_FCODE+1)*(2*MAX_MV+1) );
 668
 669         for(f_code=1; f_code<=MAX_FCODE; f_code++){
 670             for(mv=-MAX_MV; mv<=MAX_MV; mv++){
 671                 int len;
 672
 673                 if(mv==0) len= mbMotionVectorTable[0][1];
 674                 else{
 675                     int val, bit_size, range, code;
 676
 677                     bit_size = s->f_code - 1;
 678                     range = 1 << bit_size;
 679
 680                     val=mv;
 681                     if (val < 0)
 682                         val = -val;
 683                     val--;
 684                     code = (val >> bit_size) + 1;
 685                     if(code<17){
 686                         len= mbMotionVectorTable[code][1] + 1 + bit_size;
 687                     }else{
 688                         len= mbMotionVectorTable[16][1] + 2 + bit_size;
 689                     }
 690                 }
 691
 692                 mv_penalty[f_code][mv+MAX_MV]= len;
 693             }
 694         }
 695
 696
 697         for(f_code=MAX_FCODE; f_code>0; f_code--){
 698             for(mv=-(8<<f_code); mv<(8<<f_code); mv++){
 699                 fcode_tab[mv+MAX_MV]= f_code;
 700             }
 701         }
 702     }
 703     s->me.mv_penalty= mv_penalty;
 704     s->fcode_tab= fcode_tab;
 705     s->min_qcoeff=-255;
 706     s->max_qcoeff= 255;
 707     s->intra_ac_vlc_length=
 708     s->inter_ac_vlc_length= uni_mpeg1_ac_vlc_len;
 709 }
 710
 711 static inline void encode_dc(MpegEncContext *s, int diff, int component)
 712 {
 713     if (component == 0) {
 714         put_bits(
 715             &s->pb,
 716             mpeg1_lum_dc_uni[diff+255]&0xFF,
 717             mpeg1_lum_dc_uni[diff+255]>>8);
 718     } else {
 719         put_bits(
 720             &s->pb,
 721             mpeg1_chr_dc_uni[diff+255]&0xFF,
 722             mpeg1_chr_dc_uni[diff+255]>>8);
 723     }
 724 }
 725
 726 static void mpeg1_encode_block(MpegEncContext *s,
 727                                DCTELEM *block,
 728                                int n)
 729 {
 730     int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign;
 731     int code, component;
 732 //    RLTable *rl = &rl_mpeg1;
 733
 734     last_index = s->block_last_index[n];
 735
 736     /* DC coef */
 737     if (s->mb_intra) {
 738         component = (n <= 3 ? 0 : n - 4 + 1);
 739         dc = block[0]; /* overflow is impossible */
 740         diff = dc - s->last_dc[component];
 741         encode_dc(s, diff, component);
 742         s->last_dc[component] = dc;
 743         i = 1;
 744     } else {
 745         /* encode the first coefficient : needs to be done here because
 746            it is handled slightly differently */
 747         level = block[0];
 748         if (abs(level) == 1) {
 749                 code = ((uint32_t)level >> 31); /* the sign bit */
 750                 put_bits(&s->pb, 2, code | 0x02);
 751                 i = 1;
 752         } else {
 753             i = 0;
 754             last_non_zero = -1;
 755             goto next_coef;
 756         }
 757     }
 758
 759     /* now quantify & encode AC coefs */
 760     last_non_zero = i - 1;
 761
 762     for(;i<=last_index;i++) {
 763         j = s->intra_scantable.permutated[i];
 764         level = block[j];
 765     next_coef:
 766 #if 0
 767         if (level != 0)
 768             dprintf("level[%d]=%d\n", i, level);
 769 #endif
 770         /* encode using VLC */
 771         if (level != 0) {
 772             run = i - last_non_zero - 1;
 773
 774             alevel= level;
 775             MASK_ABS(sign, alevel)
 776             sign&=1;
 777
 778 //            code = get_rl_index(rl, 0, run, alevel);
 779             if (alevel <= mpeg1_max_level[0][run]){
 780                 code= mpeg1_index_run[0][run] + alevel - 1;
 781                 /* store the vlc & sign at once */
 782                 put_bits(&s->pb, mpeg1_vlc[code][1]+1, (mpeg1_vlc[code][0]<<1) + sign);
 783             } else {
 784                 /* escape seems to be pretty rare <5% so i dont optimize it */
 785                 put_bits(&s->pb, mpeg1_vlc[111/*rl->n*/][1], mpeg1_vlc[111/*rl->n*/][0]);
 786                 /* escape: only clip in this case */
 787                 put_bits(&s->pb, 6, run);
 788                 if (alevel < 128) {
 789                     put_bits(&s->pb, 8, level & 0xff);
 790                 } else {
 791                     if (level < 0) {
 792                         put_bits(&s->pb, 16, 0x8001 + level + 255);
 793                     } else {
 794                         put_bits(&s->pb, 16, level & 0xffff);
 795                     }
 796                 }
 797             }
 798             last_non_zero = i;
 799         }
 800     }
 801     /* end of block */
 802     put_bits(&s->pb, 2, 0x2);
 803 }
 804 #endif //CONFIG_ENCODERS
 805
 806 /******************************************/
 807 /* decoding */
 808
 809 static VLC dc_lum_vlc;
 810 static VLC dc_chroma_vlc;
 811 static VLC mv_vlc;
 812 static VLC mbincr_vlc;
 813 static VLC mb_ptype_vlc;
 814 static VLC mb_btype_vlc;
 815 static VLC mb_pat_vlc;
 816
 817 static void init_vlcs(MpegEncContext *s)
 818 {
 819     static int done = 0;
 820
 821     if (!done) {
 822         done = 1;
 823
 824         init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12,
 825                  vlc_dc_lum_bits, 1, 1,
 826                  vlc_dc_lum_code, 2, 2);
 827         init_vlc(&dc_chroma_vlc,  DC_VLC_BITS, 12,
 828                  vlc_dc_chroma_bits, 1, 1,
 829                  vlc_dc_chroma_code, 2, 2);
 830         init_vlc(&mv_vlc, MV_VLC_BITS, 17,
 831                  &mbMotionVectorTable[0][1], 2, 1,
 832                  &mbMotionVectorTable[0][0], 2, 1);
 833         init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36,
 834                  &mbAddrIncrTable[0][1], 2, 1,
 835                  &mbAddrIncrTable[0][0], 2, 1);
 836         init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 63,
 837                  &mbPatTable[0][1], 2, 1,
 838                  &mbPatTable[0][0], 2, 1);
 839
 840         init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
 841                  &table_mb_ptype[0][1], 2, 1,
 842                  &table_mb_ptype[0][0], 2, 1);
 843         init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
 844                  &table_mb_btype[0][1], 2, 1,
 845                  &table_mb_btype[0][0], 2, 1);
 846         init_rl(&rl_mpeg1);
 847         init_rl(&rl_mpeg2);
 848
 849         init_2d_vlc_rl(&rl_mpeg1);
 850         init_2d_vlc_rl(&rl_mpeg2);
 851     }
 852 }
 853
 854 static inline int get_dmv(MpegEncContext *s)
 855 {
 856     if(get_bits1(&s->gb))
 857         return 1 - (get_bits1(&s->gb) << 1);
 858     else
 859         return 0;
 860 }
 861
 862 static inline int get_qscale(MpegEncContext *s)
 863 {
 864     int qscale = get_bits(&s->gb, 5);
 865     if (s->mpeg2) {
 866         if (s->q_scale_type) {
 867             return non_linear_qscale[qscale];
 868         } else {
 869             return qscale << 1;
 870         }
 871     }
 872     return qscale;
 873 }
 874
 875 /* motion type (for mpeg2) */
 876 #define MT_FIELD 1
 877 #define MT_FRAME 2
 878 #define MT_16X8  2
 879 #define MT_DMV   3
 880
 881 static int mpeg_decode_mb(MpegEncContext *s,
 882                           DCTELEM block[6][64])
 883 {
 884     int i, j, k, cbp, val, mb_type, motion_type;
 885
 886     dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 887
 888     assert(s->mb_skiped==0);
 889
 890     if (s->mb_skip_run-- != 0) {
 891         if(s->pict_type == I_TYPE){
 892             fprintf(stderr, "skiped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
 893             return -1;
 894         }
 895
 896         /* skip mb */
 897         s->mb_intra = 0;
 898         for(i=0;i<6;i++)
 899             s->block_last_index[i] = -1;
 900         s->mv_type = MV_TYPE_16X16;
 901         if (s->pict_type == P_TYPE) {
 902             /* if P type, zero motion vector is implied */
 903             s->mv_dir = MV_DIR_FORWARD;
 904             s->mv[0][0][0] = s->mv[0][0][1] = 0;
 905             s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
 906             s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
 907             s->mb_skiped = 1;
 908             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 909         } else {
 910             /* if B type, reuse previous vectors and directions */
 911             s->mv[0][0][0] = s->last_mv[0][0][0];
 912             s->mv[0][0][1] = s->last_mv[0][0][1];
 913             s->mv[1][0][0] = s->last_mv[1][0][0];
 914             s->mv[1][0][1] = s->last_mv[1][0][1];
 915
 916             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
 917                 s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1] | MB_TYPE_SKIP;
 918 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
 919
 920             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
 921                 s->mb_skiped = 1;
 922         }
 923
 924         return 0;
 925     }
 926
 927     switch(s->pict_type) {
 928     default:
 929     case I_TYPE:
 930         if (get_bits1(&s->gb) == 0) {
 931             if (get_bits1(&s->gb) == 0)
 932                 return -1;
 933             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 934         } else {
 935             mb_type = MB_TYPE_INTRA;
 936         }
 937         break;
 938     case P_TYPE:
 939         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 940         if (mb_type < 0){
 941             fprintf(stderr, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 942             return -1;
 943         }
 944         mb_type = ptype2mb_type[ mb_type ];
 945         break;
 946     case B_TYPE:
 947         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 948         if (mb_type < 0){
 949             fprintf(stderr, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 950             return -1;
 951         }
 952         mb_type = btype2mb_type[ mb_type ];
 953         break;
 954     }
 955     dprintf("mb_type=%x\n", mb_type);
 956 //    motion_type = 0; /* avoid warning */
 957     if (IS_INTRA(mb_type)) {
 958         /* compute dct type */
 959         if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
 960             !s->frame_pred_frame_dct) {
 961             s->interlaced_dct = get_bits1(&s->gb);
 962         }
 963
 964         if (IS_QUANT(mb_type))
 965             s->qscale = get_qscale(s);
 966
 967         if (s->concealment_motion_vectors) {
 968             /* just parse them */
 969             if (s->picture_structure != PICT_FRAME)
 970                 skip_bits1(&s->gb); /* field select */
 971
 972             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
 973                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
 974             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
 975                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
 976
 977             skip_bits1(&s->gb); /* marker */
 978         }else
 979             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 980         s->mb_intra = 1;
 981
 982         if (s->mpeg2) {
 983             for(i=0;i<6;i++) {
 984                 if (mpeg2_decode_block_intra(s, block[i], i) < 0)
 985                     return -1;
 986             }
 987         } else {
 988             for(i=0;i<6;i++) {
 989                 if (mpeg1_decode_block_intra(s, block[i], i) < 0)
 990                     return -1;
 991             }
 992         }
 993     } else {
 994         if (mb_type & MB_TYPE_ZERO_MV){
 995             assert(mb_type & MB_TYPE_PAT);
 996
 997             /* compute dct type */
 998             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
 999                 !s->frame_pred_frame_dct) {
1000                 s->interlaced_dct = get_bits1(&s->gb);
1001             }
1002
1003             if (IS_QUANT(mb_type))
1004                 s->qscale = get_qscale(s);
1005
1006             s->mv_dir = MV_DIR_FORWARD;
1007             s->mv_type = MV_TYPE_16X16;
1008             s->last_mv[0][0][0] = 0;
1009             s->last_mv[0][0][1] = 0;
1010             s->last_mv[0][1][0] = 0;
1011             s->last_mv[0][1][1] = 0;
1012             s->mv[0][0][0] = 0;
1013             s->mv[0][0][1] = 0;
1014         }else{
1015             assert(mb_type & MB_TYPE_L0L1);
1016 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
1017             /* get additionnal motion vector type */
1018             if (s->frame_pred_frame_dct)
1019                 motion_type = MT_FRAME;
1020             else{
1021                 motion_type = get_bits(&s->gb, 2);
1022             }
1023
1024             /* compute dct type */
1025             if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
1026                 !s->frame_pred_frame_dct && IS_PAT(mb_type)) {
1027                 s->interlaced_dct = get_bits1(&s->gb);
1028             }
1029
1030             if (IS_QUANT(mb_type))
1031                 s->qscale = get_qscale(s);
1032
1033             /* motion vectors */
1034             s->mv_dir = 0;
1035             for(i=0;i<2;i++) {
1036                 if (USES_LIST(mb_type, i)) {
1037                     s->mv_dir |= (MV_DIR_FORWARD >> i);
1038                     dprintf("motion_type=%d\n", motion_type);
1039                     switch(motion_type) {
1040                     case MT_FRAME: /* or MT_16X8 */
1041                         if (s->picture_structure == PICT_FRAME) {
1042                             /* MT_FRAME */
1043                             mb_type |= MB_TYPE_16x16;
1044                             s->mv_type = MV_TYPE_16X16;
1045                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
1046                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
1047                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
1048                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
1049                             /* full_pel: only for mpeg1 */
1050                             if (s->full_pel[i]){
1051                                 s->mv[i][0][0] <<= 1;
1052                                 s->mv[i][0][1] <<= 1;
1053                             }
1054                         } else {
1055                             /* MT_16X8 */
1056                             mb_type |= MB_TYPE_16x8;
1057                             s->mv_type = MV_TYPE_16X8;
1058                             for(j=0;j<2;j++) {
1059                                 s->field_select[i][j] = get_bits1(&s->gb);
1060                                 for(k=0;k<2;k++) {
1061                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1062                                                              s->last_mv[i][j][k]);
1063                                     s->last_mv[i][j][k] = val;
1064                                     s->mv[i][j][k] = val;
1065                                 }
1066                             }
1067                         }
1068                         break;
1069                     case MT_FIELD:
1070                         s->mv_type = MV_TYPE_FIELD;
1071                         if (s->picture_structure == PICT_FRAME) {
1072                             mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
1073                             for(j=0;j<2;j++) {
1074                                 s->field_select[i][j] = get_bits1(&s->gb);
1075                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1076                                                          s->last_mv[i][j][0]);
1077                                 s->last_mv[i][j][0] = val;
1078                                 s->mv[i][j][0] = val;
1079                                 dprintf("fmx=%d\n", val);
1080                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1081                                                          s->last_mv[i][j][1] >> 1);
1082                                 s->last_mv[i][j][1] = val << 1;
1083                                 s->mv[i][j][1] = val;
1084                                 dprintf("fmy=%d\n", val);
1085                             }
1086                         } else {
1087                             mb_type |= MB_TYPE_16x16;
1088                             s->field_select[i][0] = get_bits1(&s->gb);
1089                             for(k=0;k<2;k++) {
1090                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
1091                                                          s->last_mv[i][0][k]);
1092                                 s->last_mv[i][0][k] = val;
1093                                 s->last_mv[i][1][k] = val;
1094                                 s->mv[i][0][k] = val;
1095                             }
1096                         }
1097                         break;
1098                     case MT_DMV:
1099                         {
1100                             int dmx, dmy, mx, my, m;
1101
1102                             mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1103                                                     s->last_mv[i][0][0]);
1104                             s->last_mv[i][0][0] = mx;
1105                             s->last_mv[i][1][0] = mx;
1106                             dmx = get_dmv(s);
1107                             my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1108                                                     s->last_mv[i][0][1] >> 1);
1109                             dmy = get_dmv(s);
1110                             s->mv_type = MV_TYPE_DMV;
1111                             /* XXX: totally broken */
1112                             if (s->picture_structure == PICT_FRAME) {
1113                                 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1114
1115                                 s->last_mv[i][0][1] = my << 1;
1116                                 s->last_mv[i][1][1] = my << 1;
1117
1118                                 m = s->top_field_first ? 1 : 3;
1119                                 /* top -> top pred */
1120                                 s->mv[i][0][0] = mx;
1121                                 s->mv[i][0][1] = my << 1;
1122                                 s->mv[i][1][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1123                                 s->mv[i][1][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1124                                 m = 4 - m;
1125                                 s->mv[i][2][0] = mx;
1126                                 s->mv[i][2][1] = my << 1;
1127                                 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1128                                 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1129                             } else {
1130                                 mb_type |= MB_TYPE_16x16;
1131
1132                                 s->last_mv[i][0][1] = my;
1133                                 s->last_mv[i][1][1] = my;
1134                                 s->mv[i][0][0] = mx;
1135                                 s->mv[i][0][1] = my;
1136                                 s->mv[i][1][0] = ((mx + (mx > 0)) >> 1) + dmx;
1137                                 s->mv[i][1][1] = ((my + (my > 0)) >> 1) + dmy - 1
1138                                     /* + 2 * cur_field */;
1139                             }
1140                         }
1141                         break;
1142                     }
1143                 }
1144             }
1145         }
1146
1147         s->mb_intra = 0;
1148
1149         if (IS_PAT(mb_type)) {
1150             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1151             if (cbp < 0){
1152                 fprintf(stderr, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1153                 return -1;
1154             }
1155             cbp++;
1156
1157             if (s->mpeg2) {
1158                 for(i=0;i<6;i++) {
1159                     if (cbp & 32) {
1160                         if (mpeg2_decode_block_non_intra(s, block[i], i) < 0)
1161                             return -1;
1162                     } else {
1163                         s->block_last_index[i] = -1;
1164                     }
1165                     cbp+=cbp;
1166                 }
1167             } else {
1168                 for(i=0;i<6;i++) {
1169                     if (cbp & 32) {
1170                         if (mpeg1_decode_block_inter(s, block[i], i) < 0)
1171                             return -1;
1172                     } else {
1173                         s->block_last_index[i] = -1;
1174                     }
1175                     cbp+=cbp;
1176                 }
1177             }
1178         }else{
1179             for(i=0;i<6;i++)
1180                 s->block_last_index[i] = -1;
1181         }
1182     }
1183
1184     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
1185
1186     return 0;
1187 }
1188
1189 /* as h263, but only 17 codes */
1190 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
1191 {
1192     int code, sign, val, l, shift;
1193
1194     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
1195     if (code == 0) {
1196         return pred;
1197     }
1198     if (code < 0) {
1199         return 0xffff;
1200     }
1201
1202     sign = get_bits1(&s->gb);
1203     shift = fcode - 1;
1204     val = code;
1205     if (shift) {
1206         val = (val - 1) << shift;
1207         val |= get_bits(&s->gb, shift);
1208         val++;
1209     }
1210     if (sign)
1211         val = -val;
1212     val += pred;
1213
1214     /* modulo decoding */
1215     l = 1 << (shift+4);
1216     val = ((val + l)&(l*2-1)) - l;
1217     return val;
1218 }
1219
1220 static inline int decode_dc(MpegEncContext *s, int component)
1221 {
1222     int code, diff;
1223
1224     if (component == 0) {
1225         code = get_vlc2(&s->gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
1226     } else {
1227         code = get_vlc2(&s->gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
1228     }
1229     if (code < 0){
1230         fprintf(stderr, "invalid dc code at %d %d\n", s->mb_x, s->mb_y);
1231         return 0xffff;
1232     }
1233     if (code == 0) {
1234         diff = 0;
1235     } else {
1236         diff = get_xbits(&s->gb, code);
1237     }
1238     return diff;
1239 }
1240
1241 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
1242                                DCTELEM *block,
1243                                int n)
1244 {
1245     int level, dc, diff, i, j, run;
1246     int component;
1247     RLTable *rl = &rl_mpeg1;
1248     uint8_t * const scantable= s->intra_scantable.permutated;
1249     const uint16_t *quant_matrix= s->intra_matrix;
1250     const int qscale= s->qscale;
1251
1252     /* DC coef */
1253     component = (n <= 3 ? 0 : n - 4 + 1);
1254     diff = decode_dc(s, component);
1255     if (diff >= 0xffff)
1256         return -1;
1257     dc = s->last_dc[component];
1258     dc += diff;
1259     s->last_dc[component] = dc;
1260     block[0] = dc<<3;
1261     dprintf("dc=%d diff=%d\n", dc, diff);
1262     i = 0;
1263     {
1264         OPEN_READER(re, &s->gb);
1265         /* now quantify & encode AC coefs */
1266         for(;;) {
1267             UPDATE_CACHE(re, &s->gb);
1268             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1269
1270             if(level == 127){
1271                 break;
1272             } else if(level != 0) {
1273                 i += run;
1274                 j = scantable[i];
1275                 level= (level*qscale*quant_matrix[j])>>3;
1276                 level= (level-1)|1;
1277                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1278                 LAST_SKIP_BITS(re, &s->gb, 1);
1279             } else {
1280                 /* escape */
1281                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1282                 UPDATE_CACHE(re, &s->gb);
1283                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1284                 if (level == -128) {
1285                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1286                 } else if (level == 0) {
1287                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1288                 }
1289                 i += run;
1290                 j = scantable[i];
1291                 if(level<0){
1292                     level= -level;
1293                     level= (level*qscale*quant_matrix[j])>>3;
1294                     level= (level-1)|1;
1295                     level= -level;
1296                 }else{
1297                     level= (level*qscale*quant_matrix[j])>>3;
1298                     level= (level-1)|1;
1299                 }
1300             }
1301             if (i > 63){
1302                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1303                 return -1;
1304             }
1305
1306             block[j] = level;
1307         }
1308         CLOSE_READER(re, &s->gb);
1309     }
1310     s->block_last_index[n] = i;
1311    return 0;
1312 }
1313
1314 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
1315                                DCTELEM *block,
1316                                int n)
1317 {
1318     int level, i, j, run;
1319     RLTable *rl = &rl_mpeg1;
1320     uint8_t * const scantable= s->intra_scantable.permutated;
1321     const uint16_t *quant_matrix= s->inter_matrix;
1322     const int qscale= s->qscale;
1323
1324     {
1325         int v;
1326         OPEN_READER(re, &s->gb);
1327         i = -1;
1328         /* special case for the first coef. no need to add a second vlc table */
1329         UPDATE_CACHE(re, &s->gb);
1330         v= SHOW_UBITS(re, &s->gb, 2);
1331         if (v & 2) {
1332             LAST_SKIP_BITS(re, &s->gb, 2);
1333             level= (3*qscale*quant_matrix[0])>>4;
1334             level= (level-1)|1;
1335             if(v&1)
1336                 level= -level;
1337             block[0] = level;
1338             i++;
1339         }
1340
1341         /* now quantify & encode AC coefs */
1342         for(;;) {
1343             UPDATE_CACHE(re, &s->gb);
1344             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1345
1346             if(level == 127){
1347                 break;
1348             } else if(level != 0) {
1349                 i += run;
1350                 j = scantable[i];
1351                 level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1352                 level= (level-1)|1;
1353                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1354                 LAST_SKIP_BITS(re, &s->gb, 1);
1355             } else {
1356                 /* escape */
1357                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1358                 UPDATE_CACHE(re, &s->gb);
1359                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
1360                 if (level == -128) {
1361                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
1362                 } else if (level == 0) {
1363                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
1364                 }
1365                 i += run;
1366                 j = scantable[i];
1367                 if(level<0){
1368                     level= -level;
1369                     level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1370                     level= (level-1)|1;
1371                     level= -level;
1372                 }else{
1373                     level= ((level*2+1)*qscale*quant_matrix[j])>>4;
1374                     level= (level-1)|1;
1375                 }
1376             }
1377             if (i > 63){
1378                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1379                 return -1;
1380             }
1381
1382             block[j] = level;
1383         }
1384         CLOSE_READER(re, &s->gb);
1385     }
1386     s->block_last_index[n] = i;
1387     return 0;
1388 }
1389
1390 /* Also does unquantization here, since I will never support mpeg2
1391    encoding */
1392 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
1393                                DCTELEM *block,
1394                                int n)
1395 {
1396     int level, i, j, run;
1397     RLTable *rl = &rl_mpeg1;
1398     uint8_t * const scantable= s->intra_scantable.permutated;
1399     const uint16_t *quant_matrix;
1400     const int qscale= s->qscale;
1401     int mismatch;
1402
1403     mismatch = 1;
1404
1405     {
1406         int v;
1407         OPEN_READER(re, &s->gb);
1408         i = -1;
1409         if (n < 4)
1410             quant_matrix = s->inter_matrix;
1411         else
1412             quant_matrix = s->chroma_inter_matrix;
1413
1414         /* special case for the first coef. no need to add a second vlc table */
1415         UPDATE_CACHE(re, &s->gb);
1416         v= SHOW_UBITS(re, &s->gb, 2);
1417         if (v & 2) {
1418             LAST_SKIP_BITS(re, &s->gb, 2);
1419             level= (3*qscale*quant_matrix[0])>>5;
1420             if(v&1)
1421                 level= -level;
1422             block[0] = level;
1423             mismatch ^= level;
1424             i++;
1425         }
1426
1427         /* now quantify & encode AC coefs */
1428         for(;;) {
1429             UPDATE_CACHE(re, &s->gb);
1430             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1431
1432             if(level == 127){
1433                 break;
1434             } else if(level != 0) {
1435                 i += run;
1436                 j = scantable[i];
1437                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1438                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1439                 LAST_SKIP_BITS(re, &s->gb, 1);
1440             } else {
1441                 /* escape */
1442                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1443                 UPDATE_CACHE(re, &s->gb);
1444                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1445
1446                 i += run;
1447                 j = scantable[i];
1448                 if(level<0){
1449                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
1450                     level= -level;
1451                 }else{
1452                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
1453                 }
1454             }
1455             if (i > 63){
1456                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1457                 return -1;
1458             }
1459
1460             mismatch ^= level;
1461             block[j] = level;
1462         }
1463         CLOSE_READER(re, &s->gb);
1464     }
1465     block[63] ^= (mismatch & 1);
1466
1467     s->block_last_index[n] = i;
1468     return 0;
1469 }
1470
1471 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1472                                DCTELEM *block,
1473                                int n)
1474 {
1475     int level, dc, diff, i, j, run;
1476     int component;
1477     RLTable *rl;
1478     uint8_t * const scantable= s->intra_scantable.permutated;
1479     const uint16_t *quant_matrix;
1480     const int qscale= s->qscale;
1481     int mismatch;
1482
1483     /* DC coef */
1484     if (n < 4){
1485         quant_matrix = s->intra_matrix;
1486         component = 0;
1487     }else{
1488         quant_matrix = s->chroma_intra_matrix;
1489         component = n - 3;
1490     }
1491     diff = decode_dc(s, component);
1492     if (diff >= 0xffff)
1493         return -1;
1494     dc = s->last_dc[component];
1495     dc += diff;
1496     s->last_dc[component] = dc;
1497     block[0] = dc << (3 - s->intra_dc_precision);
1498     dprintf("dc=%d\n", block[0]);
1499     mismatch = block[0] ^ 1;
1500     i = 0;
1501     if (s->intra_vlc_format)
1502         rl = &rl_mpeg2;
1503     else
1504         rl = &rl_mpeg1;
1505
1506     {
1507         OPEN_READER(re, &s->gb);
1508         /* now quantify & encode AC coefs */
1509         for(;;) {
1510             UPDATE_CACHE(re, &s->gb);
1511             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2);
1512
1513             if(level == 127){
1514                 break;
1515             } else if(level != 0) {
1516                 i += run;
1517                 j = scantable[i];
1518                 level= (level*qscale*quant_matrix[j])>>4;
1519                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1520                 LAST_SKIP_BITS(re, &s->gb, 1);
1521             } else {
1522                 /* escape */
1523                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1524                 UPDATE_CACHE(re, &s->gb);
1525                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1526                 i += run;
1527                 j = scantable[i];
1528                 if(level<0){
1529                     level= (-level*qscale*quant_matrix[j])>>4;
1530                     level= -level;
1531                 }else{
1532                     level= (level*qscale*quant_matrix[j])>>4;
1533                 }
1534             }
1535             if (i > 63){
1536                 fprintf(stderr, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1537                 return -1;
1538             }
1539
1540             mismatch^= level;
1541             block[j] = level;
1542         }
1543         CLOSE_READER(re, &s->gb);
1544     }
1545     block[63]^= mismatch&1;
1546
1547     s->block_last_index[n] = i;
1548     return 0;
1549 }
1550
1551 typedef struct Mpeg1Context {
1552     MpegEncContext mpeg_enc_ctx;
1553     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1554     int repeat_field; /* true if we must repeat the field */
1555 } Mpeg1Context;
1556
1557 static int mpeg_decode_init(AVCodecContext *avctx)
1558 {
1559     Mpeg1Context *s = avctx->priv_data;
1560
1561     s->mpeg_enc_ctx.flags= avctx->flags;
1562     common_init(&s->mpeg_enc_ctx);
1563     init_vlcs(&s->mpeg_enc_ctx);
1564
1565     s->mpeg_enc_ctx_allocated = 0;
1566     s->mpeg_enc_ctx.picture_number = 0;
1567     s->repeat_field = 0;
1568     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1569     return 0;
1570 }
1571
1572 /* return the 8 bit start code value and update the search
1573    state. Return -1 if no start code found */
1574 static int find_start_code(uint8_t **pbuf_ptr, uint8_t *buf_end)
1575 {
1576     uint8_t *buf_ptr;
1577     unsigned int state=0xFFFFFFFF, v;
1578     int val;
1579
1580     buf_ptr = *pbuf_ptr;
1581     while (buf_ptr < buf_end) {
1582         v = *buf_ptr++;
1583         if (state == 0x000001) {
1584             state = ((state << 8) | v) & 0xffffff;
1585             val = state;
1586             goto found;
1587         }
1588         state = ((state << 8) | v) & 0xffffff;
1589     }
1590     val = -1;
1591  found:
1592     *pbuf_ptr = buf_ptr;
1593     return val;
1594 }
1595
1596 static int mpeg1_decode_picture(AVCodecContext *avctx,
1597                                 uint8_t *buf, int buf_size)
1598 {
1599     Mpeg1Context *s1 = avctx->priv_data;
1600     MpegEncContext *s = &s1->mpeg_enc_ctx;
1601     int ref, f_code;
1602
1603     init_get_bits(&s->gb, buf, buf_size*8);
1604
1605     ref = get_bits(&s->gb, 10); /* temporal ref */
1606     s->pict_type = get_bits(&s->gb, 3);
1607     dprintf("pict_type=%d number=%d\n", s->pict_type, s->picture_number);
1608
1609     skip_bits(&s->gb, 16);
1610     if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
1611         s->full_pel[0] = get_bits1(&s->gb);
1612         f_code = get_bits(&s->gb, 3);
1613         if (f_code == 0)
1614             return -1;
1615         s->mpeg_f_code[0][0] = f_code;
1616         s->mpeg_f_code[0][1] = f_code;
1617     }
1618     if (s->pict_type == B_TYPE) {
1619         s->full_pel[1] = get_bits1(&s->gb);
1620         f_code = get_bits(&s->gb, 3);
1621         if (f_code == 0)
1622             return -1;
1623         s->mpeg_f_code[1][0] = f_code;
1624         s->mpeg_f_code[1][1] = f_code;
1625     }
1626     s->current_picture.pict_type= s->pict_type;
1627     s->current_picture.key_frame= s->pict_type == I_TYPE;
1628
1629     s->y_dc_scale = 8;
1630     s->c_dc_scale = 8;
1631     s->first_slice = 1;
1632     return 0;
1633 }
1634
1635 static void mpeg_decode_sequence_extension(MpegEncContext *s)
1636 {
1637     int horiz_size_ext, vert_size_ext;
1638     int bit_rate_ext, vbv_buf_ext;
1639     int frame_rate_ext_n, frame_rate_ext_d;
1640     float aspect;
1641
1642     skip_bits(&s->gb, 8); /* profil and level */
1643     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1644     skip_bits(&s->gb, 2); /* chroma_format */
1645     horiz_size_ext = get_bits(&s->gb, 2);
1646     vert_size_ext = get_bits(&s->gb, 2);
1647     s->width |= (horiz_size_ext << 12);
1648     s->height |= (vert_size_ext << 12);
1649     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1650     s->bit_rate = ((s->bit_rate / 400) | (bit_rate_ext << 12)) * 400;
1651     skip_bits1(&s->gb); /* marker */
1652     vbv_buf_ext = get_bits(&s->gb, 8);
1653     s->low_delay = get_bits1(&s->gb);
1654     frame_rate_ext_n = get_bits(&s->gb, 2);
1655     frame_rate_ext_d = get_bits(&s->gb, 5);
1656     av_reduce(
1657         &s->avctx->frame_rate,
1658         &s->avctx->frame_rate_base,
1659         frame_rate_tab[s->frame_rate_index] * (frame_rate_ext_n+1),
1660         MPEG1_FRAME_RATE_BASE * (frame_rate_ext_d+1),
1661         1<<30);
1662
1663     dprintf("sequence extension\n");
1664     s->mpeg2 = 1;
1665     s->avctx->sub_id = 2; /* indicates mpeg2 found */
1666
1667     aspect= mpeg2_aspect[s->aspect_ratio_info];
1668     if(aspect>0.0)      s->avctx->aspect_ratio= s->width/(aspect*s->height);
1669     else if(aspect<0.0) s->avctx->aspect_ratio= -1.0/aspect;
1670 }
1671
1672 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1673 {
1674     int i, v, j;
1675
1676     dprintf("matrix extension\n");
1677
1678     if (get_bits1(&s->gb)) {
1679         for(i=0;i<64;i++) {
1680             v = get_bits(&s->gb, 8);
1681             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1682             s->intra_matrix[j] = v;
1683             s->chroma_intra_matrix[j] = v;
1684         }
1685     }
1686     if (get_bits1(&s->gb)) {
1687         for(i=0;i<64;i++) {
1688             v = get_bits(&s->gb, 8);
1689             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1690             s->inter_matrix[j] = v;
1691             s->chroma_inter_matrix[j] = v;
1692         }
1693     }
1694     if (get_bits1(&s->gb)) {
1695         for(i=0;i<64;i++) {
1696             v = get_bits(&s->gb, 8);
1697             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1698             s->chroma_intra_matrix[j] = v;
1699         }
1700     }
1701     if (get_bits1(&s->gb)) {
1702         for(i=0;i<64;i++) {
1703             v = get_bits(&s->gb, 8);
1704             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1705             s->chroma_inter_matrix[j] = v;
1706         }
1707     }
1708 }
1709
1710 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1711 {
1712     s->full_pel[0] = s->full_pel[1] = 0;
1713     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1714     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1715     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1716     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1717     s->intra_dc_precision = get_bits(&s->gb, 2);
1718     s->picture_structure = get_bits(&s->gb, 2);
1719     s->top_field_first = get_bits1(&s->gb);
1720     s->frame_pred_frame_dct = get_bits1(&s->gb);
1721     s->concealment_motion_vectors = get_bits1(&s->gb);
1722     s->q_scale_type = get_bits1(&s->gb);
1723     s->intra_vlc_format = get_bits1(&s->gb);
1724     s->alternate_scan = get_bits1(&s->gb);
1725     s->repeat_first_field = get_bits1(&s->gb);
1726     s->chroma_420_type = get_bits1(&s->gb);
1727     s->progressive_frame = get_bits1(&s->gb);
1728
1729     if(s->picture_structure == PICT_FRAME)
1730         s->first_field=0;
1731     else{
1732         s->first_field ^= 1;
1733         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1734     }
1735
1736     if(s->alternate_scan){
1737         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1738         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1739         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
1740         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
1741     }else{
1742         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1743         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1744         ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
1745         ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
1746     }
1747
1748     /* composite display not parsed */
1749     dprintf("intra_dc_precision=%d\n", s->intra_dc_precision);
1750     dprintf("picture_structure=%d\n", s->picture_structure);
1751     dprintf("top field first=%d\n", s->top_field_first);
1752     dprintf("repeat first field=%d\n", s->repeat_first_field);
1753     dprintf("conceal=%d\n", s->concealment_motion_vectors);
1754     dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
1755     dprintf("alternate_scan=%d\n", s->alternate_scan);
1756     dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1757     dprintf("progressive_frame=%d\n", s->progressive_frame);
1758 }
1759
1760 static void mpeg_decode_extension(AVCodecContext *avctx,
1761                                   uint8_t *buf, int buf_size)
1762 {
1763     Mpeg1Context *s1 = avctx->priv_data;
1764     MpegEncContext *s = &s1->mpeg_enc_ctx;
1765     int ext_type;
1766
1767     init_get_bits(&s->gb, buf, buf_size*8);
1768
1769     ext_type = get_bits(&s->gb, 4);
1770     switch(ext_type) {
1771     case 0x1:
1772         /* sequence ext */
1773         mpeg_decode_sequence_extension(s);
1774         break;
1775     case 0x3:
1776         /* quant matrix extension */
1777         mpeg_decode_quant_matrix_extension(s);
1778         break;
1779     case 0x8:
1780         /* picture extension */
1781         mpeg_decode_picture_coding_extension(s);
1782         break;
1783     }
1784 }
1785
1786 #define DECODE_SLICE_FATAL_ERROR -2
1787 #define DECODE_SLICE_ERROR -1
1788 #define DECODE_SLICE_OK 0
1789
1790 /**
1791  * decodes a slice.
1792  * @return DECODE_SLICE_FATAL_ERROR if a non recoverable error occured<br>
1793  *         DECODE_SLICE_ERROR if the slice is damaged<br>
1794  *         DECODE_SLICE_OK if this slice is ok<br>
1795  */
1796 static int mpeg_decode_slice(AVCodecContext *avctx,
1797                               AVFrame *pict,
1798                               int start_code,
1799                               uint8_t **buf, int buf_size)
1800 {
1801     Mpeg1Context *s1 = avctx->priv_data;
1802     MpegEncContext *s = &s1->mpeg_enc_ctx;
1803     int ret;
1804     const int field_pic= s->picture_structure != PICT_FRAME;
1805
1806     s->resync_mb_x= s->mb_x =
1807     s->resync_mb_y= s->mb_y = -1;
1808
1809     start_code = (start_code - 1) & 0xff;
1810     if (start_code >= s->mb_height){
1811         fprintf(stderr, "slice below image (%d >= %d)\n", start_code, s->mb_height);
1812         return -1;
1813     }
1814
1815     ff_mpeg1_clean_buffers(s);
1816     s->interlaced_dct = 0;
1817
1818     /* start frame decoding */
1819     if (s->first_slice) {
1820       if(s->first_field || s->picture_structure==PICT_FRAME){
1821         if(MPV_frame_start(s, avctx) < 0)
1822             return DECODE_SLICE_FATAL_ERROR;
1823
1824         ff_er_frame_start(s);
1825
1826         /* first check if we must repeat the frame */
1827         s->current_picture.repeat_pict = 0;
1828
1829         if (s->repeat_first_field) {
1830             if (s->progressive_sequence) {
1831                 if (s->top_field_first)
1832                     s->current_picture.repeat_pict = 4;
1833                 else
1834                     s->current_picture.repeat_pict = 2;
1835             } else if (s->progressive_frame) {
1836                 s->current_picture.repeat_pict = 1;
1837             }
1838         }
1839 //        printf("%d \n", s->current_picture.repeat_pict);
1840
1841         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1842              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",
1843                  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],
1844                  s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")),
1845                  s->progressive_sequence ? "pro" :"", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1846                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1847                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1848         }
1849       }else{ //second field
1850             int i;
1851
1852             if(!s->current_picture_ptr){
1853                 fprintf(stderr, "first field missing\n");
1854                 return -1;
1855             }
1856
1857             for(i=0; i<4; i++){
1858                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1859                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1860                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1861                 }
1862             }
1863       }
1864     }
1865     s->first_slice = 0;
1866
1867     init_get_bits(&s->gb, *buf, buf_size*8);
1868
1869     s->qscale = get_qscale(s);
1870     if(s->qscale == 0){
1871         fprintf(stderr, "qscale == 0\n");
1872         return -1;
1873     }
1874
1875     /* extra slice info */
1876     while (get_bits1(&s->gb) != 0) {
1877         skip_bits(&s->gb, 8);
1878     }
1879
1880     s->mb_x=0;
1881
1882     for(;;) {
1883         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1884         if (code < 0){
1885             fprintf(stderr, "first mb_incr damaged\n");
1886             return -1;
1887         }
1888         if (code >= 33) {
1889             if (code == 33) {
1890                 s->mb_x += 33;
1891             }
1892             /* otherwise, stuffing, nothing to do */
1893         } else {
1894             s->mb_x += code;
1895             break;
1896         }
1897     }
1898
1899     s->resync_mb_x= s->mb_x;
1900     s->resync_mb_y= s->mb_y = start_code;
1901     s->mb_skip_run= 0;
1902
1903     for(;;) {
1904         s->dsp.clear_blocks(s->block[0]);
1905
1906         ret = mpeg_decode_mb(s, s->block);
1907
1908         dprintf("ret=%d\n", ret);
1909         if (ret < 0)
1910             return -1;
1911
1912         if(s->motion_val && s->pict_type != B_TYPE){ //note motion_val is normally NULL unless we want to extract the MVs
1913             const int wrap = s->block_wrap[0];
1914             const int xy = s->mb_x*2 + 1 + (s->mb_y*2 +1)*wrap;
1915             int motion_x, motion_y;
1916
1917             if (s->mb_intra) {
1918                 motion_x = motion_y = 0;
1919             }else if (s->mv_type == MV_TYPE_16X16) {
1920                 motion_x = s->mv[0][0][0];
1921                 motion_y = s->mv[0][0][1];
1922             } else /*if (s->mv_type == MV_TYPE_FIELD)*/ {
1923                 motion_x = s->mv[0][0][0] + s->mv[0][1][0];
1924                 motion_y = s->mv[0][0][1] + s->mv[0][1][1];
1925                 motion_x = (motion_x>>1) | (motion_x&1);
1926             }
1927             s->motion_val[xy][0] = motion_x;
1928             s->motion_val[xy][1] = motion_y;
1929             s->motion_val[xy + 1][0] = motion_x;
1930             s->motion_val[xy + 1][1] = motion_y;
1931             s->motion_val[xy + wrap][0] = motion_x;
1932             s->motion_val[xy + wrap][1] = motion_y;
1933             s->motion_val[xy + 1 + wrap][0] = motion_x;
1934             s->motion_val[xy + 1 + wrap][1] = motion_y;
1935         }
1936
1937         MPV_decode_mb(s, s->block);
1938
1939         if (++s->mb_x >= s->mb_width) {
1940             if(s->picture_structure==PICT_FRAME){
1941                 ff_draw_horiz_band(s, 16*s->mb_y, 16);
1942             }else{
1943                 if(!s->first_field){
1944                     ff_draw_horiz_band(s, 32*s->mb_y, 32);
1945                 }
1946             }
1947
1948             s->mb_x = 0;
1949             s->mb_y++;
1950
1951             if(s->mb_y<<field_pic >= s->mb_height){
1952                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1953
1954                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)))
1955                    || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
1956                     fprintf(stderr, "end missmatch left=%d\n", left);
1957                     return -1;
1958                 }else
1959                     goto eos;
1960             }
1961         }
1962
1963         /* skip mb handling */
1964         if (s->mb_skip_run == -1) {
1965             /* read again increment */
1966             s->mb_skip_run = 0;
1967             for(;;) {
1968                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1969                 if (code < 0){
1970                     fprintf(stderr, "mb incr damaged\n");
1971                     return -1;
1972                 }
1973                 if (code >= 33) {
1974                     if (code == 33) {
1975                         s->mb_skip_run += 33;
1976                     }else if(code == 35){
1977                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1978                             fprintf(stderr, "slice missmatch\n");
1979                             return -1;
1980                         }
1981                         goto eos; /* end of slice */
1982                     }
1983                     /* otherwise, stuffing, nothing to do */
1984                 } else {
1985                     s->mb_skip_run += code;
1986                     break;
1987                 }
1988             }
1989         }
1990     }
1991 eos: // end of slice
1992     *buf += get_bits_count(&s->gb)/8 - 1;
1993 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1994     return 0;
1995 }
1996
1997 /**
1998  * handles slice ends.
1999  * @return 1 if it seems to be the last slice of
2000  */
2001 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2002 {
2003     Mpeg1Context *s1 = avctx->priv_data;
2004     MpegEncContext *s = &s1->mpeg_enc_ctx;
2005
2006     if (!s1->mpeg_enc_ctx_allocated)
2007         return 0;
2008
2009     /* end of slice reached */
2010     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
2011         /* end of image */
2012
2013         if(s->mpeg2){
2014             s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
2015         }else
2016             s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG1;
2017
2018         ff_er_frame_end(s);
2019
2020         MPV_frame_end(s);
2021
2022         if (s->pict_type == B_TYPE || s->low_delay) {
2023             *pict= *(AVFrame*)&s->current_picture;
2024             ff_print_debug_info(s, s->current_picture_ptr);
2025         } else {
2026             s->picture_number++;
2027             /* latency of 1 frame for I and P frames */
2028             /* XXX: use another variable than picture_number */
2029             if (s->last_picture_ptr != NULL) {
2030                 *pict= *(AVFrame*)&s->last_picture;
2031                  ff_print_debug_info(s, s->last_picture_ptr);
2032             }
2033         }
2034         return 1;
2035     } else {
2036         return 0;
2037     }
2038 }
2039
2040 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2041                                  uint8_t *buf, int buf_size)
2042 {
2043     Mpeg1Context *s1 = avctx->priv_data;
2044     MpegEncContext *s = &s1->mpeg_enc_ctx;
2045     int width, height, i, v, j;
2046     float aspect;
2047
2048     init_get_bits(&s->gb, buf, buf_size*8);
2049
2050     width = get_bits(&s->gb, 12);
2051     height = get_bits(&s->gb, 12);
2052     s->aspect_ratio_info= get_bits(&s->gb, 4);
2053     if(!s->mpeg2){
2054         aspect= mpeg1_aspect[s->aspect_ratio_info];
2055         if(aspect!=0.0) avctx->aspect_ratio= width/(aspect*height);
2056     }
2057
2058     s->frame_rate_index = get_bits(&s->gb, 4);
2059     if (s->frame_rate_index == 0)
2060         return -1;
2061     s->bit_rate = get_bits(&s->gb, 18) * 400;
2062     if (get_bits1(&s->gb) == 0) /* marker */
2063         return -1;
2064     if (width <= 0 || height <= 0 ||
2065         (width % 2) != 0 || (height % 2) != 0)
2066         return -1;
2067     if (width != s->width ||
2068         height != s->height) {
2069         /* start new mpeg1 context decoding */
2070         s->out_format = FMT_MPEG1;
2071         if (s1->mpeg_enc_ctx_allocated) {
2072             MPV_common_end(s);
2073         }
2074         s->width = width;
2075         s->height = height;
2076         avctx->has_b_frames= 1;
2077         s->avctx = avctx;
2078         avctx->width = width;
2079         avctx->height = height;
2080         av_reduce(
2081             &avctx->frame_rate,
2082             &avctx->frame_rate_base,
2083             frame_rate_tab[s->frame_rate_index],
2084             MPEG1_FRAME_RATE_BASE, //FIXME store in allready reduced form
2085             1<<30
2086             );
2087         avctx->bit_rate = s->bit_rate;
2088
2089         if (MPV_common_init(s) < 0)
2090             return -1;
2091         s1->mpeg_enc_ctx_allocated = 1;
2092     }
2093
2094     skip_bits(&s->gb, 10); /* vbv_buffer_size */
2095     skip_bits(&s->gb, 1);
2096
2097     /* get matrix */
2098     if (get_bits1(&s->gb)) {
2099         for(i=0;i<64;i++) {
2100             v = get_bits(&s->gb, 8);
2101             j = s->intra_scantable.permutated[i];
2102             s->intra_matrix[j] = v;
2103             s->chroma_intra_matrix[j] = v;
2104         }
2105 #ifdef DEBUG
2106         dprintf("intra matrix present\n");
2107         for(i=0;i<64;i++)
2108             dprintf(" %d", s->intra_matrix[s->intra_scantable.permutated[i]]);
2109         printf("\n");
2110 #endif
2111     } else {
2112         for(i=0;i<64;i++) {
2113             int j= s->dsp.idct_permutation[i];
2114             v = ff_mpeg1_default_intra_matrix[i];
2115             s->intra_matrix[j] = v;
2116             s->chroma_intra_matrix[j] = v;
2117         }
2118     }
2119     if (get_bits1(&s->gb)) {
2120         for(i=0;i<64;i++) {
2121             v = get_bits(&s->gb, 8);
2122             j = s->intra_scantable.permutated[i];
2123             s->inter_matrix[j] = v;
2124             s->chroma_inter_matrix[j] = v;
2125         }
2126 #ifdef DEBUG
2127         dprintf("non intra matrix present\n");
2128         for(i=0;i<64;i++)
2129             dprintf(" %d", s->inter_matrix[s->intra_scantable.permutated[i]]);
2130         printf("\n");
2131 #endif
2132     } else {
2133         for(i=0;i<64;i++) {
2134             int j= s->dsp.idct_permutation[i];
2135             v = ff_mpeg1_default_non_intra_matrix[i];
2136             s->inter_matrix[j] = v;
2137             s->chroma_inter_matrix[j] = v;
2138         }
2139     }
2140
2141     /* we set mpeg2 parameters so that it emulates mpeg1 */
2142     s->progressive_sequence = 1;
2143     s->progressive_frame = 1;
2144     s->picture_structure = PICT_FRAME;
2145     s->frame_pred_frame_dct = 1;
2146     s->mpeg2 = 0;
2147     avctx->sub_id = 1; /* indicates mpeg1 */
2148     return 0;
2149 }
2150
2151 static void mpeg_decode_user_data(AVCodecContext *avctx,
2152                                   const uint8_t *buf, int buf_size)
2153 {
2154     const uint8_t *p;
2155     int len, flags;
2156     p = buf;
2157     len = buf_size;
2158
2159     /* we parse the DTG active format information */
2160     if (len >= 5 &&
2161         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2162         flags = p[4];
2163         p += 5;
2164         len -= 5;
2165         if (flags & 0x80) {
2166             /* skip event id */
2167             if (len < 2)
2168                 return;
2169             p += 2;
2170             len -= 2;
2171         }
2172         if (flags & 0x40) {
2173             if (len < 1)
2174                 return;
2175             avctx->dtg_active_format = p[0] & 0x0f;
2176         }
2177     }
2178 }
2179
2180 /**
2181  * finds the end of the current frame in the bitstream.
2182  * @return the position of the first byte of the next frame, or -1
2183  */
2184 static int mpeg1_find_frame_end(MpegEncContext *s, uint8_t *buf, int buf_size){
2185     ParseContext *pc= &s->parse_context;
2186     int i;
2187     uint32_t state;
2188
2189     state= pc->state;
2190
2191     i=0;
2192     if(!pc->frame_start_found){
2193         for(i=0; i<buf_size; i++){
2194             state= (state<<8) | buf[i];
2195             if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2196                 i++;
2197                 pc->frame_start_found=1;
2198                 break;
2199             }
2200         }
2201     }
2202
2203     if(pc->frame_start_found){
2204         for(; i<buf_size; i++){
2205             state= (state<<8) | buf[i];
2206             if((state&0xFFFFFF00) == 0x100){
2207                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2208                     pc->frame_start_found=0;
2209                     pc->state=-1;
2210                     return i-3;
2211                 }
2212             }
2213         }
2214     }
2215     pc->state= state;
2216     return END_NOT_FOUND;
2217 }
2218
2219 /* handle buffering and image synchronisation */
2220 static int mpeg_decode_frame(AVCodecContext *avctx,
2221                              void *data, int *data_size,
2222                              uint8_t *buf, int buf_size)
2223 {
2224     Mpeg1Context *s = avctx->priv_data;
2225     uint8_t *buf_end, *buf_ptr;
2226     int ret, start_code, input_size;
2227     AVFrame *picture = data;
2228     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2229     dprintf("fill_buffer\n");
2230
2231     *data_size = 0;
2232
2233     /* special case for last picture */
2234     if (buf_size == 0) {
2235         if (s2->picture_number > 0) {
2236             *picture= *(AVFrame*)&s2->next_picture;
2237
2238             *data_size = sizeof(AVFrame);
2239         }
2240         return 0;
2241     }
2242
2243     if(s2->flags&CODEC_FLAG_TRUNCATED){
2244         int next= mpeg1_find_frame_end(s2, buf, buf_size);
2245
2246         if( ff_combine_frame(s2, next, &buf, &buf_size) < 0 )
2247             return buf_size;
2248     }
2249
2250     buf_ptr = buf;
2251     buf_end = buf + buf_size;
2252
2253 #if 0
2254     if (s->repeat_field % 2 == 1) {
2255         s->repeat_field++;
2256         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2257         //        s2->picture_number, s->repeat_field);
2258         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2259             *data_size = sizeof(AVPicture);
2260             goto the_end;
2261         }
2262     }
2263 #endif
2264     for(;;) {
2265         /* find start next code */
2266         start_code = find_start_code(&buf_ptr, buf_end);
2267         if (start_code < 0){
2268             if (slice_end(avctx, picture)) {
2269                 if(s2->last_picture_ptr) //FIXME merge with the stuff in mpeg_decode_slice
2270                     *data_size = sizeof(AVPicture);
2271             }
2272             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2273         }
2274
2275         input_size = buf_end - buf_ptr;
2276
2277         if(avctx->debug & FF_DEBUG_STARTCODE){
2278             printf("%3X at %d left %d\n", start_code, buf_ptr-buf, input_size);
2279         }
2280
2281                 /* prepare data for next start code */
2282                 switch(start_code) {
2283                 case SEQ_START_CODE:
2284                     mpeg1_decode_sequence(avctx, buf_ptr,
2285                                           input_size);
2286                     break;
2287
2288                 case PICTURE_START_CODE:
2289                     /* we have a complete image : we try to decompress it */
2290                     mpeg1_decode_picture(avctx,
2291                                          buf_ptr, input_size);
2292                     break;
2293                 case EXT_START_CODE:
2294                     mpeg_decode_extension(avctx,
2295                                           buf_ptr, input_size);
2296                     break;
2297                 case USER_START_CODE:
2298                     mpeg_decode_user_data(avctx,
2299                                           buf_ptr, input_size);
2300                     break;
2301                 default:
2302                     if (start_code >= SLICE_MIN_START_CODE &&
2303                         start_code <= SLICE_MAX_START_CODE) {
2304
2305                         /* skip b frames if we dont have reference frames */
2306                         if(s2->last_picture_ptr==NULL && s2->pict_type==B_TYPE) break;
2307                         /* skip b frames if we are in a hurry */
2308                         if(avctx->hurry_up && s2->pict_type==B_TYPE) break;
2309                         /* skip everything if we are in a hurry>=5 */
2310                         if(avctx->hurry_up>=5) break;
2311
2312                         if (!s->mpeg_enc_ctx_allocated) break;
2313
2314                         ret = mpeg_decode_slice(avctx, picture,
2315                                                 start_code, &buf_ptr, input_size);
2316                         emms_c();
2317
2318                         if(ret < 0){
2319                             if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2320                                 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);
2321                             if(ret==DECODE_SLICE_FATAL_ERROR) return -1;
2322                         }else{
2323                             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);
2324                         }
2325                     }
2326                     break;
2327                 }
2328     }
2329 }
2330
2331 static int mpeg_decode_end(AVCodecContext *avctx)
2332 {
2333     Mpeg1Context *s = avctx->priv_data;
2334
2335     if (s->mpeg_enc_ctx_allocated)
2336         MPV_common_end(&s->mpeg_enc_ctx);
2337     return 0;
2338 }
2339
2340 AVCodec mpeg_decoder = {
2341     "mpegvideo",
2342     CODEC_TYPE_VIDEO,
2343     CODEC_ID_MPEG1VIDEO,
2344     sizeof(Mpeg1Context),
2345     mpeg_decode_init,
2346     NULL,
2347     mpeg_decode_end,
2348     mpeg_decode_frame,
2349     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
2350 };