git.sesse.net Git - ffmpeg/blob - libavcodec/mpeg12.c

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