git.sesse.net Git - ffmpeg/blob - libavcodec/msmpeg4dec.c

   1 /*
   2  * MSMPEG4 backend for encoder and decoder
   3  * Copyright (c) 2001 Fabrice Bellard
   4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * msmpeg4v1 & v2 stuff by Michael Niedermayer <michaelni@gmx.at>
   7  *
   8  * This file is part of Libav.
   9  *
  10  * Libav is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * Libav is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with Libav; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  23  */
  24
  25 #include "avcodec.h"
  26 #include "internal.h"
  27 #include "mpegutils.h"
  28 #include "mpegvideo.h"
  29 #include "msmpeg4.h"
  30 #include "h263.h"
  31 #include "mpeg4video.h"
  32 #include "msmpeg4data.h"
  33 #include "vc1data.h"
  34 #include "wmv2.h"
  35
  36 #define DC_VLC_BITS 9
  37 #define V2_INTRA_CBPC_VLC_BITS 3
  38 #define V2_MB_TYPE_VLC_BITS 7
  39 #define MV_VLC_BITS 9
  40 #define V2_MV_VLC_BITS 9
  41 #define TEX_VLC_BITS 9
  42
  43 #define DEFAULT_INTER_INDEX 3
  44
  45 static inline int msmpeg4v1_pred_dc(MpegEncContext * s, int n,
  46                                     int32_t **dc_val_ptr)
  47 {
  48     int i;
  49
  50     if (n < 4) {
  51         i= 0;
  52     } else {
  53         i= n-3;
  54     }
  55
  56     *dc_val_ptr= &s->last_dc[i];
  57     return s->last_dc[i];
  58 }
  59
  60 /****************************************/
  61 /* decoding stuff */
  62
  63 VLC ff_mb_non_intra_vlc[4];
  64 static VLC v2_dc_lum_vlc;
  65 static VLC v2_dc_chroma_vlc;
  66 static VLC v2_intra_cbpc_vlc;
  67 static VLC v2_mb_type_vlc;
  68 static VLC v2_mv_vlc;
  69 VLC ff_inter_intra_vlc;
  70
  71 /* This is identical to H.263 except that its range is multiplied by 2. */
  72 static int msmpeg4v2_decode_motion(MpegEncContext * s, int pred, int f_code)
  73 {
  74     int code, val, sign, shift;
  75
  76     code = get_vlc2(&s->gb, v2_mv_vlc.table, V2_MV_VLC_BITS, 2);
  77     ff_dlog(s, "MV code %d at %d %d pred: %d\n", code, s->mb_x,s->mb_y, pred);
  78     if (code < 0)
  79         return 0xffff;
  80
  81     if (code == 0)
  82         return pred;
  83     sign = get_bits1(&s->gb);
  84     shift = f_code - 1;
  85     val = code;
  86     if (shift) {
  87         val = (val - 1) << shift;
  88         val |= get_bits(&s->gb, shift);
  89         val++;
  90     }
  91     if (sign)
  92         val = -val;
  93
  94     val += pred;
  95     if (val <= -64)
  96         val += 64;
  97     else if (val >= 64)
  98         val -= 64;
  99
 100     return val;
 101 }
 102
 103 static int msmpeg4v12_decode_mb(MpegEncContext *s, int16_t block[6][64])
 104 {
 105     int cbp, code, i;
 106
 107     if (s->pict_type == AV_PICTURE_TYPE_P) {
 108         if (s->use_skip_mb_code) {
 109             if (get_bits1(&s->gb)) {
 110                 /* skip mb */
 111                 s->mb_intra = 0;
 112                 for(i=0;i<6;i++)
 113                     s->block_last_index[i] = -1;
 114                 s->mv_dir = MV_DIR_FORWARD;
 115                 s->mv_type = MV_TYPE_16X16;
 116                 s->mv[0][0][0] = 0;
 117                 s->mv[0][0][1] = 0;
 118                 s->mb_skipped = 1;
 119                 return 0;
 120             }
 121         }
 122
 123         if(s->msmpeg4_version==2)
 124             code = get_vlc2(&s->gb, v2_mb_type_vlc.table, V2_MB_TYPE_VLC_BITS, 1);
 125         else
 126             code = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
 127         if(code<0 || code>7){
 128             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", code, s->mb_x, s->mb_y);
 129             return -1;
 130         }
 131
 132         s->mb_intra = code >>2;
 133
 134         cbp = code & 0x3;
 135     } else {
 136         s->mb_intra = 1;
 137         if(s->msmpeg4_version==2)
 138             cbp= get_vlc2(&s->gb, v2_intra_cbpc_vlc.table, V2_INTRA_CBPC_VLC_BITS, 1);
 139         else
 140             cbp= get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 1);
 141         if(cbp<0 || cbp>3){
 142             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
 143             return -1;
 144         }
 145     }
 146
 147     if (!s->mb_intra) {
 148         int mx, my, cbpy;
 149
 150         cbpy= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
 151         if(cbpy<0){
 152             av_log(s->avctx, AV_LOG_ERROR, "cbpy %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
 153             return -1;
 154         }
 155
 156         cbp|= cbpy<<2;
 157         if(s->msmpeg4_version==1 || (cbp&3) != 3) cbp^= 0x3C;
 158
 159         ff_h263_pred_motion(s, 0, 0, &mx, &my);
 160         mx= msmpeg4v2_decode_motion(s, mx, 1);
 161         my= msmpeg4v2_decode_motion(s, my, 1);
 162
 163         s->mv_dir = MV_DIR_FORWARD;
 164         s->mv_type = MV_TYPE_16X16;
 165         s->mv[0][0][0] = mx;
 166         s->mv[0][0][1] = my;
 167     } else {
 168         if(s->msmpeg4_version==2){
 169             s->ac_pred = get_bits1(&s->gb);
 170             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
 171         } else{
 172             s->ac_pred = 0;
 173             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
 174             if(s->pict_type==AV_PICTURE_TYPE_P) cbp^=0x3C;
 175         }
 176     }
 177
 178     s->bdsp.clear_blocks(s->block[0]);
 179     for (i = 0; i < 6; i++) {
 180         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
 181         {
 182              av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
 183              return -1;
 184         }
 185     }
 186     return 0;
 187 }
 188
 189 static int msmpeg4v34_decode_mb(MpegEncContext *s, int16_t block[6][64])
 190 {
 191     int cbp, code, i;
 192     uint8_t *coded_val;
 193     uint32_t * const mb_type_ptr = &s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride];
 194
 195     if (s->pict_type == AV_PICTURE_TYPE_P) {
 196         if (s->use_skip_mb_code) {
 197             if (get_bits1(&s->gb)) {
 198                 /* skip mb */
 199                 s->mb_intra = 0;
 200                 for(i=0;i<6;i++)
 201                     s->block_last_index[i] = -1;
 202                 s->mv_dir = MV_DIR_FORWARD;
 203                 s->mv_type = MV_TYPE_16X16;
 204                 s->mv[0][0][0] = 0;
 205                 s->mv[0][0][1] = 0;
 206                 s->mb_skipped = 1;
 207                 *mb_type_ptr = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 208
 209                 return 0;
 210             }
 211         }
 212
 213         code = get_vlc2(&s->gb, ff_mb_non_intra_vlc[DEFAULT_INTER_INDEX].table, MB_NON_INTRA_VLC_BITS, 3);
 214         if (code < 0)
 215             return -1;
 216         //s->mb_intra = (code & 0x40) ? 0 : 1;
 217         s->mb_intra = (~code & 0x40) >> 6;
 218
 219         cbp = code & 0x3f;
 220     } else {
 221         s->mb_intra = 1;
 222         code = get_vlc2(&s->gb, ff_msmp4_mb_i_vlc.table, MB_INTRA_VLC_BITS, 2);
 223         if (code < 0)
 224             return -1;
 225         /* predict coded block pattern */
 226         cbp = 0;
 227         for(i=0;i<6;i++) {
 228             int val = ((code >> (5 - i)) & 1);
 229             if (i < 4) {
 230                 int pred = ff_msmpeg4_coded_block_pred(s, i, &coded_val);
 231                 val = val ^ pred;
 232                 *coded_val = val;
 233             }
 234             cbp |= val << (5 - i);
 235         }
 236     }
 237
 238     if (!s->mb_intra) {
 239         int mx, my;
 240         if(s->per_mb_rl_table && cbp){
 241             s->rl_table_index = decode012(&s->gb);
 242             s->rl_chroma_table_index = s->rl_table_index;
 243         }
 244         ff_h263_pred_motion(s, 0, 0, &mx, &my);
 245         if (ff_msmpeg4_decode_motion(s, &mx, &my) < 0)
 246             return -1;
 247         s->mv_dir = MV_DIR_FORWARD;
 248         s->mv_type = MV_TYPE_16X16;
 249         s->mv[0][0][0] = mx;
 250         s->mv[0][0][1] = my;
 251         *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16;
 252     } else {
 253         ff_dlog(s, "I at %d %d %d %06X\n", s->mb_x, s->mb_y,
 254                 ((cbp & 3) ? 1 : 0) +((cbp & 0x3C)? 2 : 0),
 255                 show_bits(&s->gb, 24));
 256         s->ac_pred = get_bits1(&s->gb);
 257         *mb_type_ptr = MB_TYPE_INTRA;
 258         if(s->inter_intra_pred){
 259             s->h263_aic_dir= get_vlc2(&s->gb, ff_inter_intra_vlc.table, INTER_INTRA_VLC_BITS, 1);
 260             ff_dlog(s, "%d%d %d %d/",
 261                     s->ac_pred, s->h263_aic_dir, s->mb_x, s->mb_y);
 262         }
 263         if(s->per_mb_rl_table && cbp){
 264             s->rl_table_index = decode012(&s->gb);
 265             s->rl_chroma_table_index = s->rl_table_index;
 266         }
 267     }
 268
 269     s->bdsp.clear_blocks(s->block[0]);
 270     for (i = 0; i < 6; i++) {
 271         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
 272         {
 273             av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
 274             return -1;
 275         }
 276     }
 277
 278     return 0;
 279 }
 280
 281 /* init all vlc decoding tables */
 282 av_cold int ff_msmpeg4_decode_init(AVCodecContext *avctx)
 283 {
 284     MpegEncContext *s = avctx->priv_data;
 285     static int done = 0;
 286     int i;
 287     MVTable *mv;
 288
 289     if (ff_h263_decode_init(avctx) < 0)
 290         return -1;
 291
 292     ff_msmpeg4_common_init(s);
 293
 294     if (!done) {
 295         done = 1;
 296
 297         for(i=0;i<NB_RL_TABLES;i++) {
 298             ff_rl_init(&ff_rl_table[i], ff_static_rl_table_store[i]);
 299         }
 300         INIT_VLC_RL(ff_rl_table[0], 642);
 301         INIT_VLC_RL(ff_rl_table[1], 1104);
 302         INIT_VLC_RL(ff_rl_table[2], 554);
 303         INIT_VLC_RL(ff_rl_table[3], 940);
 304         INIT_VLC_RL(ff_rl_table[4], 962);
 305         INIT_VLC_RL(ff_rl_table[5], 554);
 306
 307         mv = &ff_mv_tables[0];
 308         INIT_VLC_STATIC(&mv->vlc, MV_VLC_BITS, mv->n + 1,
 309                     mv->table_mv_bits, 1, 1,
 310                     mv->table_mv_code, 2, 2, 3714);
 311         mv = &ff_mv_tables[1];
 312         INIT_VLC_STATIC(&mv->vlc, MV_VLC_BITS, mv->n + 1,
 313                     mv->table_mv_bits, 1, 1,
 314                     mv->table_mv_code, 2, 2, 2694);
 315
 316         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[0], DC_VLC_BITS, 120,
 317                  &ff_table0_dc_lum[0][1], 8, 4,
 318                  &ff_table0_dc_lum[0][0], 8, 4, 1158);
 319         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[0], DC_VLC_BITS, 120,
 320                  &ff_table0_dc_chroma[0][1], 8, 4,
 321                  &ff_table0_dc_chroma[0][0], 8, 4, 1118);
 322         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[1], DC_VLC_BITS, 120,
 323                  &ff_table1_dc_lum[0][1], 8, 4,
 324                  &ff_table1_dc_lum[0][0], 8, 4, 1476);
 325         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[1], DC_VLC_BITS, 120,
 326                  &ff_table1_dc_chroma[0][1], 8, 4,
 327                  &ff_table1_dc_chroma[0][0], 8, 4, 1216);
 328
 329         INIT_VLC_STATIC(&v2_dc_lum_vlc, DC_VLC_BITS, 512,
 330                  &ff_v2_dc_lum_table[0][1], 8, 4,
 331                  &ff_v2_dc_lum_table[0][0], 8, 4, 1472);
 332         INIT_VLC_STATIC(&v2_dc_chroma_vlc, DC_VLC_BITS, 512,
 333                  &ff_v2_dc_chroma_table[0][1], 8, 4,
 334                  &ff_v2_dc_chroma_table[0][0], 8, 4, 1506);
 335
 336         INIT_VLC_STATIC(&v2_intra_cbpc_vlc, V2_INTRA_CBPC_VLC_BITS, 4,
 337                  &ff_v2_intra_cbpc[0][1], 2, 1,
 338                  &ff_v2_intra_cbpc[0][0], 2, 1, 8);
 339         INIT_VLC_STATIC(&v2_mb_type_vlc, V2_MB_TYPE_VLC_BITS, 8,
 340                  &ff_v2_mb_type[0][1], 2, 1,
 341                  &ff_v2_mb_type[0][0], 2, 1, 128);
 342         INIT_VLC_STATIC(&v2_mv_vlc, V2_MV_VLC_BITS, 33,
 343                  &ff_mvtab[0][1], 2, 1,
 344                  &ff_mvtab[0][0], 2, 1, 538);
 345
 346         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[0], MB_NON_INTRA_VLC_BITS, 128,
 347                      &ff_wmv2_inter_table[0][0][1], 8, 4,
 348                      &ff_wmv2_inter_table[0][0][0], 8, 4, 1636);
 349         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[1], MB_NON_INTRA_VLC_BITS, 128,
 350                      &ff_wmv2_inter_table[1][0][1], 8, 4,
 351                      &ff_wmv2_inter_table[1][0][0], 8, 4, 2648);
 352         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[2], MB_NON_INTRA_VLC_BITS, 128,
 353                      &ff_wmv2_inter_table[2][0][1], 8, 4,
 354                      &ff_wmv2_inter_table[2][0][0], 8, 4, 1532);
 355         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[3], MB_NON_INTRA_VLC_BITS, 128,
 356                      &ff_wmv2_inter_table[3][0][1], 8, 4,
 357                      &ff_wmv2_inter_table[3][0][0], 8, 4, 2488);
 358
 359         INIT_VLC_STATIC(&ff_msmp4_mb_i_vlc, MB_INTRA_VLC_BITS, 64,
 360                  &ff_msmp4_mb_i_table[0][1], 4, 2,
 361                  &ff_msmp4_mb_i_table[0][0], 4, 2, 536);
 362
 363         INIT_VLC_STATIC(&ff_inter_intra_vlc, INTER_INTRA_VLC_BITS, 4,
 364                  &ff_table_inter_intra[0][1], 2, 1,
 365                  &ff_table_inter_intra[0][0], 2, 1, 8);
 366     }
 367
 368     switch(s->msmpeg4_version){
 369     case 1:
 370     case 2:
 371         s->decode_mb= msmpeg4v12_decode_mb;
 372         break;
 373     case 3:
 374     case 4:
 375         s->decode_mb= msmpeg4v34_decode_mb;
 376         break;
 377     case 5:
 378         if (CONFIG_WMV2_DECODER)
 379             s->decode_mb= ff_wmv2_decode_mb;
 380     case 6:
 381         //FIXME + TODO VC1 decode mb
 382         break;
 383     }
 384
 385     s->slice_height= s->mb_height; //to avoid 1/0 if the first frame is not a keyframe
 386
 387     return 0;
 388 }
 389
 390 int ff_msmpeg4_decode_picture_header(MpegEncContext * s)
 391 {
 392     int code;
 393
 394     if(s->msmpeg4_version==1){
 395         int start_code = get_bits_long(&s->gb, 32);
 396         if(start_code!=0x00000100){
 397             av_log(s->avctx, AV_LOG_ERROR, "invalid startcode\n");
 398             return -1;
 399         }
 400
 401         skip_bits(&s->gb, 5); // frame number */
 402     }
 403
 404     s->pict_type = get_bits(&s->gb, 2) + 1;
 405     if (s->pict_type != AV_PICTURE_TYPE_I &&
 406         s->pict_type != AV_PICTURE_TYPE_P){
 407         av_log(s->avctx, AV_LOG_ERROR, "invalid picture type\n");
 408         return -1;
 409     }
 410 #if 0
 411 {
 412     static int had_i=0;
 413     if(s->pict_type == AV_PICTURE_TYPE_I) had_i=1;
 414     if(!had_i) return -1;
 415 }
 416 #endif
 417     s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
 418     if(s->qscale==0){
 419         av_log(s->avctx, AV_LOG_ERROR, "invalid qscale\n");
 420         return -1;
 421     }
 422
 423     if (s->pict_type == AV_PICTURE_TYPE_I) {
 424         code = get_bits(&s->gb, 5);
 425         if(s->msmpeg4_version==1){
 426             if(code==0 || code>s->mb_height){
 427                 av_log(s->avctx, AV_LOG_ERROR, "invalid slice height %d\n", code);
 428                 return -1;
 429             }
 430
 431             s->slice_height = code;
 432         }else{
 433             /* 0x17: one slice, 0x18: two slices, ... */
 434             if (code < 0x17){
 435                 av_log(s->avctx, AV_LOG_ERROR, "error, slice code was %X\n", code);
 436                 return -1;
 437             }
 438
 439             s->slice_height = s->mb_height / (code - 0x16);
 440         }
 441
 442         switch(s->msmpeg4_version){
 443         case 1:
 444         case 2:
 445             s->rl_chroma_table_index = 2;
 446             s->rl_table_index = 2;
 447
 448             s->dc_table_index = 0; //not used
 449             break;
 450         case 3:
 451             s->rl_chroma_table_index = decode012(&s->gb);
 452             s->rl_table_index = decode012(&s->gb);
 453
 454             s->dc_table_index = get_bits1(&s->gb);
 455             break;
 456         case 4:
 457             ff_msmpeg4_decode_ext_header(s, (2+5+5+17+7)/8);
 458
 459             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
 460             else                           s->per_mb_rl_table= 0;
 461
 462             if(!s->per_mb_rl_table){
 463                 s->rl_chroma_table_index = decode012(&s->gb);
 464                 s->rl_table_index = decode012(&s->gb);
 465             }
 466
 467             s->dc_table_index = get_bits1(&s->gb);
 468             s->inter_intra_pred= 0;
 469             break;
 470         }
 471         s->no_rounding = 1;
 472         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
 473             av_log(s->avctx, AV_LOG_DEBUG, "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d slice:%d   \n",
 474                 s->qscale,
 475                 s->rl_chroma_table_index,
 476                 s->rl_table_index,
 477                 s->dc_table_index,
 478                 s->per_mb_rl_table,
 479                 s->slice_height);
 480     } else {
 481         switch(s->msmpeg4_version){
 482         case 1:
 483         case 2:
 484             if(s->msmpeg4_version==1)
 485                 s->use_skip_mb_code = 1;
 486             else
 487                 s->use_skip_mb_code = get_bits1(&s->gb);
 488             s->rl_table_index = 2;
 489             s->rl_chroma_table_index = s->rl_table_index;
 490             s->dc_table_index = 0; //not used
 491             s->mv_table_index = 0;
 492             break;
 493         case 3:
 494             s->use_skip_mb_code = get_bits1(&s->gb);
 495             s->rl_table_index = decode012(&s->gb);
 496             s->rl_chroma_table_index = s->rl_table_index;
 497
 498             s->dc_table_index = get_bits1(&s->gb);
 499
 500             s->mv_table_index = get_bits1(&s->gb);
 501             break;
 502         case 4:
 503             s->use_skip_mb_code = get_bits1(&s->gb);
 504
 505             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
 506             else                           s->per_mb_rl_table= 0;
 507
 508             if(!s->per_mb_rl_table){
 509                 s->rl_table_index = decode012(&s->gb);
 510                 s->rl_chroma_table_index = s->rl_table_index;
 511             }
 512
 513             s->dc_table_index = get_bits1(&s->gb);
 514
 515             s->mv_table_index = get_bits1(&s->gb);
 516             s->inter_intra_pred= (s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE);
 517             break;
 518         }
 519
 520         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
 521             av_log(s->avctx, AV_LOG_DEBUG, "skip:%d rl:%d rlc:%d dc:%d mv:%d mbrl:%d qp:%d   \n",
 522                 s->use_skip_mb_code,
 523                 s->rl_table_index,
 524                 s->rl_chroma_table_index,
 525                 s->dc_table_index,
 526                 s->mv_table_index,
 527                 s->per_mb_rl_table,
 528                 s->qscale);
 529
 530         if(s->flipflop_rounding){
 531             s->no_rounding ^= 1;
 532         }else{
 533             s->no_rounding = 0;
 534         }
 535     }
 536     ff_dlog(s->avctx, "%d %d %d %d %d\n", s->pict_type, s->bit_rate,
 537             s->inter_intra_pred, s->width, s->height);
 538
 539     s->esc3_level_length= 0;
 540     s->esc3_run_length= 0;
 541
 542     return 0;
 543 }
 544
 545 int ff_msmpeg4_decode_ext_header(MpegEncContext * s, int buf_size)
 546 {
 547     int left= buf_size*8 - get_bits_count(&s->gb);
 548     int length= s->msmpeg4_version>=3 ? 17 : 16;
 549     /* the alt_bitstream reader could read over the end so we need to check it */
 550     if(left>=length && left<length+8)
 551     {
 552         skip_bits(&s->gb, 5); /* fps */
 553         s->bit_rate= get_bits(&s->gb, 11)*1024;
 554         if(s->msmpeg4_version>=3)
 555             s->flipflop_rounding= get_bits1(&s->gb);
 556         else
 557             s->flipflop_rounding= 0;
 558     }
 559     else if(left<length+8)
 560     {
 561         s->flipflop_rounding= 0;
 562         if(s->msmpeg4_version != 2)
 563             av_log(s->avctx, AV_LOG_ERROR, "ext header missing, %d left\n", left);
 564     }
 565     else
 566     {
 567         av_log(s->avctx, AV_LOG_ERROR, "I-frame too long, ignoring ext header\n");
 568     }
 569
 570     return 0;
 571 }
 572
 573 static int msmpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
 574 {
 575     int level, pred;
 576
 577     if(s->msmpeg4_version<=2){
 578         if (n < 4) {
 579             level = get_vlc2(&s->gb, v2_dc_lum_vlc.table, DC_VLC_BITS, 3);
 580         } else {
 581             level = get_vlc2(&s->gb, v2_dc_chroma_vlc.table, DC_VLC_BITS, 3);
 582         }
 583         if (level < 0)
 584             return -1;
 585         level-=256;
 586     }else{  //FIXME optimize use unified tables & index
 587         if (n < 4) {
 588             level = get_vlc2(&s->gb, ff_msmp4_dc_luma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
 589         } else {
 590             level = get_vlc2(&s->gb, ff_msmp4_dc_chroma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
 591         }
 592         if (level < 0){
 593             av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
 594             return -1;
 595         }
 596
 597         if (level == DC_MAX) {
 598             level = get_bits(&s->gb, 8);
 599             if (get_bits1(&s->gb))
 600                 level = -level;
 601         } else if (level != 0) {
 602             if (get_bits1(&s->gb))
 603                 level = -level;
 604         }
 605     }
 606
 607     if(s->msmpeg4_version==1){
 608         int32_t *dc_val;
 609         pred = msmpeg4v1_pred_dc(s, n, &dc_val);
 610         level += pred;
 611
 612         /* update predictor */
 613         *dc_val= level;
 614     }else{
 615         int16_t *dc_val;
 616         pred   = ff_msmpeg4_pred_dc(s, n, &dc_val, dir_ptr);
 617         level += pred;
 618
 619         /* update predictor */
 620         if (n < 4) {
 621             *dc_val = level * s->y_dc_scale;
 622         } else {
 623             *dc_val = level * s->c_dc_scale;
 624         }
 625     }
 626
 627     return level;
 628 }
 629
 630 //#define ERROR_DETAILS
 631 int ff_msmpeg4_decode_block(MpegEncContext * s, int16_t * block,
 632                               int n, int coded, const uint8_t *scan_table)
 633 {
 634     int level, i, last, run, run_diff;
 635     int av_uninit(dc_pred_dir);
 636     RLTable *rl;
 637     RL_VLC_ELEM *rl_vlc;
 638     int qmul, qadd;
 639
 640     if (s->mb_intra) {
 641         qmul=1;
 642         qadd=0;
 643
 644         /* DC coef */
 645         level = msmpeg4_decode_dc(s, n, &dc_pred_dir);
 646
 647         if (level < 0){
 648             av_log(s->avctx, AV_LOG_ERROR, "dc overflow- block: %d qscale: %d//\n", n, s->qscale);
 649             if(s->inter_intra_pred) level=0;
 650             else                    return -1;
 651         }
 652         if (n < 4) {
 653             rl = &ff_rl_table[s->rl_table_index];
 654             if(level > 256*s->y_dc_scale){
 655                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ L qscale: %d//\n", s->qscale);
 656                 if(!s->inter_intra_pred) return -1;
 657             }
 658         } else {
 659             rl = &ff_rl_table[3 + s->rl_chroma_table_index];
 660             if(level > 256*s->c_dc_scale){
 661                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ C qscale: %d//\n", s->qscale);
 662                 if(!s->inter_intra_pred) return -1;
 663             }
 664         }
 665         block[0] = level;
 666
 667         run_diff = s->msmpeg4_version >= 4;
 668         i = 0;
 669         if (!coded) {
 670             goto not_coded;
 671         }
 672         if (s->ac_pred) {
 673             if (dc_pred_dir == 0)
 674                 scan_table = s->intra_v_scantable.permutated; /* left */
 675             else
 676                 scan_table = s->intra_h_scantable.permutated; /* top */
 677         } else {
 678             scan_table = s->intra_scantable.permutated;
 679         }
 680         rl_vlc= rl->rl_vlc[0];
 681     } else {
 682         qmul = s->qscale << 1;
 683         qadd = (s->qscale - 1) | 1;
 684         i = -1;
 685         rl = &ff_rl_table[3 + s->rl_table_index];
 686
 687         if(s->msmpeg4_version==2)
 688             run_diff = 0;
 689         else
 690             run_diff = 1;
 691
 692         if (!coded) {
 693             s->block_last_index[n] = i;
 694             return 0;
 695         }
 696         if(!scan_table)
 697             scan_table = s->inter_scantable.permutated;
 698         rl_vlc= rl->rl_vlc[s->qscale];
 699     }
 700   {
 701     OPEN_READER(re, &s->gb);
 702     for(;;) {
 703         UPDATE_CACHE(re, &s->gb);
 704         GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
 705         if (level==0) {
 706             int cache;
 707             cache= GET_CACHE(re, &s->gb);
 708             /* escape */
 709             if (s->msmpeg4_version==1 || (cache&0x80000000)==0) {
 710                 if (s->msmpeg4_version==1 || (cache&0x40000000)==0) {
 711                     /* third escape */
 712                     if(s->msmpeg4_version!=1) LAST_SKIP_BITS(re, &s->gb, 2);
 713                     UPDATE_CACHE(re, &s->gb);
 714                     if(s->msmpeg4_version<=3){
 715                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
 716                         run=   SHOW_UBITS(re, &s->gb, 6); SKIP_CACHE(re, &s->gb, 6);
 717                         level= SHOW_SBITS(re, &s->gb, 8);
 718                         SKIP_COUNTER(re, &s->gb, 1+6+8);
 719                     }else{
 720                         int sign;
 721                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
 722                         if(!s->esc3_level_length){
 723                             int ll;
 724                             ff_dlog(s->avctx, "ESC-3 %X at %d %d\n",
 725                                     show_bits(&s->gb, 24), s->mb_x, s->mb_y);
 726                             if(s->qscale<8){
 727                                 ll= SHOW_UBITS(re, &s->gb, 3); SKIP_BITS(re, &s->gb, 3);
 728                                 if(ll==0){
 729                                     ll= 8+SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
 730                                 }
 731                             }else{
 732                                 ll=2;
 733                                 while(ll<8 && SHOW_UBITS(re, &s->gb, 1)==0){
 734                                     ll++;
 735                                     SKIP_BITS(re, &s->gb, 1);
 736                                 }
 737                                 if(ll<8) SKIP_BITS(re, &s->gb, 1);
 738                             }
 739
 740                             s->esc3_level_length= ll;
 741                             s->esc3_run_length= SHOW_UBITS(re, &s->gb, 2) + 3; SKIP_BITS(re, &s->gb, 2);
 742                             UPDATE_CACHE(re, &s->gb);
 743                         }
 744                         run=   SHOW_UBITS(re, &s->gb, s->esc3_run_length);
 745                         SKIP_BITS(re, &s->gb, s->esc3_run_length);
 746
 747                         sign=  SHOW_UBITS(re, &s->gb, 1);
 748                         SKIP_BITS(re, &s->gb, 1);
 749
 750                         level= SHOW_UBITS(re, &s->gb, s->esc3_level_length);
 751                         SKIP_BITS(re, &s->gb, s->esc3_level_length);
 752                         if(sign) level= -level;
 753                     }
 754
 755 #if 0 // waste of time / this will detect very few errors
 756                     {
 757                         const int abs_level= FFABS(level);
 758                         const int run1= run - rl->max_run[last][abs_level] - run_diff;
 759                         if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
 760                             if(abs_level <= rl->max_level[last][run]){
 761                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
 762                                 return DECODING_AC_LOST;
 763                             }
 764                             if(abs_level <= rl->max_level[last][run]*2){
 765                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
 766                                 return DECODING_AC_LOST;
 767                             }
 768                             if(run1>=0 && abs_level <= rl->max_level[last][run1]){
 769                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
 770                                 return DECODING_AC_LOST;
 771                             }
 772                         }
 773                     }
 774 #endif
 775                     //level = level * qmul + (level>0) * qadd - (level<=0) * qadd ;
 776                     if (level>0) level= level * qmul + qadd;
 777                     else         level= level * qmul - qadd;
 778 #if 0 // waste of time too :(
 779                     if(level>2048 || level<-2048){
 780                         av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc\n");
 781                         return DECODING_AC_LOST;
 782                     }
 783 #endif
 784                     i+= run + 1;
 785                     if(last) i+=192;
 786 #ifdef ERROR_DETAILS
 787                 if(run==66)
 788                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC3 level=%d\n", level);
 789                 else if((i>62 && i<192) || i>192+63)
 790                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC3 i=%d run=%d level=%d\n", i, run, level);
 791 #endif
 792                 } else {
 793                     /* second escape */
 794                     SKIP_BITS(re, &s->gb, 2);
 795                     GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
 796                     i+= run + rl->max_run[run>>7][level/qmul] + run_diff; //FIXME opt indexing
 797                     level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 798                     LAST_SKIP_BITS(re, &s->gb, 1);
 799 #ifdef ERROR_DETAILS
 800                 if(run==66)
 801                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC2 level=%d\n", level);
 802                 else if((i>62 && i<192) || i>192+63)
 803                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC2 i=%d run=%d level=%d\n", i, run, level);
 804 #endif
 805                 }
 806             } else {
 807                 /* first escape */
 808                 SKIP_BITS(re, &s->gb, 1);
 809                 GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
 810                 i+= run;
 811                 level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
 812                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 813                 LAST_SKIP_BITS(re, &s->gb, 1);
 814 #ifdef ERROR_DETAILS
 815                 if(run==66)
 816                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC1 level=%d\n", level);
 817                 else if((i>62 && i<192) || i>192+63)
 818                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC1 i=%d run=%d level=%d\n", i, run, level);
 819 #endif
 820             }
 821         } else {
 822             i+= run;
 823             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 824             LAST_SKIP_BITS(re, &s->gb, 1);
 825 #ifdef ERROR_DETAILS
 826                 if(run==66)
 827                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code level=%d\n", level);
 828                 else if((i>62 && i<192) || i>192+63)
 829                     av_log(s->avctx, AV_LOG_ERROR, "run overflow i=%d run=%d level=%d\n", i, run, level);
 830 #endif
 831         }
 832         if (i > 62){
 833             i-= 192;
 834             if(i&(~63)){
 835                 const int left= get_bits_left(&s->gb);
 836                 if (((i + 192 == 64 && level / qmul == -1) ||
 837                      !(s->avctx->err_recognition & AV_EF_BITSTREAM)) &&
 838                     left >= 0) {
 839                     av_log(s->avctx, AV_LOG_ERROR, "ignoring overflow at %d %d\n", s->mb_x, s->mb_y);
 840                     break;
 841                 }else{
 842                     av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 843                     return -1;
 844                 }
 845             }
 846
 847             block[scan_table[i]] = level;
 848             break;
 849         }
 850
 851         block[scan_table[i]] = level;
 852     }
 853     CLOSE_READER(re, &s->gb);
 854   }
 855  not_coded:
 856     if (s->mb_intra) {
 857         ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
 858         if (s->ac_pred) {
 859             i = 63; /* XXX: not optimal */
 860         }
 861     }
 862     if(s->msmpeg4_version>=4 && i>0) i=63; //FIXME/XXX optimize
 863     s->block_last_index[n] = i;
 864
 865     return 0;
 866 }
 867
 868 int ff_msmpeg4_decode_motion(MpegEncContext * s,
 869                                  int *mx_ptr, int *my_ptr)
 870 {
 871     MVTable *mv;
 872     int code, mx, my;
 873
 874     mv = &ff_mv_tables[s->mv_table_index];
 875
 876     code = get_vlc2(&s->gb, mv->vlc.table, MV_VLC_BITS, 2);
 877     if (code < 0){
 878         av_log(s->avctx, AV_LOG_ERROR, "illegal MV code at %d %d\n", s->mb_x, s->mb_y);
 879         return -1;
 880     }
 881     if (code == mv->n) {
 882         mx = get_bits(&s->gb, 6);
 883         my = get_bits(&s->gb, 6);
 884     } else {
 885         mx = mv->table_mvx[code];
 886         my = mv->table_mvy[code];
 887     }
 888
 889     mx += *mx_ptr - 32;
 890     my += *my_ptr - 32;
 891     /* WARNING : they do not do exactly modulo encoding */
 892     if (mx <= -64)
 893         mx += 64;
 894     else if (mx >= 64)
 895         mx -= 64;
 896
 897     if (my <= -64)
 898         my += 64;
 899     else if (my >= 64)
 900         my -= 64;
 901     *mx_ptr = mx;
 902     *my_ptr = my;
 903     return 0;
 904 }
 905
 906 AVCodec ff_msmpeg4v1_decoder = {
 907     .name           = "msmpeg4v1",
 908     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 1"),
 909     .type           = AVMEDIA_TYPE_VIDEO,
 910     .id             = AV_CODEC_ID_MSMPEG4V1,
 911     .priv_data_size = sizeof(MpegEncContext),
 912     .init           = ff_msmpeg4_decode_init,
 913     .close          = ff_h263_decode_end,
 914     .decode         = ff_h263_decode_frame,
 915     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 916     .pix_fmts       = (const enum AVPixelFormat[]) {
 917         AV_PIX_FMT_YUV420P,
 918         AV_PIX_FMT_NONE
 919     },
 920 };
 921
 922 AVCodec ff_msmpeg4v2_decoder = {
 923     .name           = "msmpeg4v2",
 924     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 2"),
 925     .type           = AVMEDIA_TYPE_VIDEO,
 926     .id             = AV_CODEC_ID_MSMPEG4V2,
 927     .priv_data_size = sizeof(MpegEncContext),
 928     .init           = ff_msmpeg4_decode_init,
 929     .close          = ff_h263_decode_end,
 930     .decode         = ff_h263_decode_frame,
 931     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 932     .pix_fmts       = (const enum AVPixelFormat[]) {
 933         AV_PIX_FMT_YUV420P,
 934         AV_PIX_FMT_NONE
 935     },
 936 };
 937
 938 AVCodec ff_msmpeg4v3_decoder = {
 939     .name           = "msmpeg4",
 940     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 3"),
 941     .type           = AVMEDIA_TYPE_VIDEO,
 942     .id             = AV_CODEC_ID_MSMPEG4V3,
 943     .priv_data_size = sizeof(MpegEncContext),
 944     .init           = ff_msmpeg4_decode_init,
 945     .close          = ff_h263_decode_end,
 946     .decode         = ff_h263_decode_frame,
 947     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 948     .pix_fmts       = (const enum AVPixelFormat[]) {
 949         AV_PIX_FMT_YUV420P,
 950         AV_PIX_FMT_NONE
 951     },
 952 };
 953
 954 AVCodec ff_wmv1_decoder = {
 955     .name           = "wmv1",
 956     .long_name      = NULL_IF_CONFIG_SMALL("Windows Media Video 7"),
 957     .type           = AVMEDIA_TYPE_VIDEO,
 958     .id             = AV_CODEC_ID_WMV1,
 959     .priv_data_size = sizeof(MpegEncContext),
 960     .init           = ff_msmpeg4_decode_init,
 961     .close          = ff_h263_decode_end,
 962     .decode         = ff_h263_decode_frame,
 963     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 964     .pix_fmts       = (const enum AVPixelFormat[]) {
 965         AV_PIX_FMT_YUV420P,
 966         AV_PIX_FMT_NONE
 967     },
 968 };