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) 2002-2013 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * msmpeg4v1 & v2 stuff by Michael Niedermayer <michaelni@gmx.at>
   7  *
   8  * This file is part of FFmpeg.
   9  *
  10  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 "mpegutils.h"
  27 #include "mpegvideo.h"
  28 #include "msmpeg4.h"
  29 #include "libavutil/imgutils.h"
  30 #include "libavutil/x86/asm.h"
  31 #include "h263.h"
  32 #include "mpeg4video.h"
  33 #include "msmpeg4data.h"
  34 #include "vc1data.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 h263 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     av_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     uint32_t * const mb_type_ptr = &s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride];
 107
 108     if (s->pict_type == AV_PICTURE_TYPE_P) {
 109         if (s->use_skip_mb_code) {
 110             if (get_bits1(&s->gb)) {
 111                 /* skip mb */
 112                 s->mb_intra = 0;
 113                 for(i=0;i<6;i++)
 114                     s->block_last_index[i] = -1;
 115                 s->mv_dir = MV_DIR_FORWARD;
 116                 s->mv_type = MV_TYPE_16X16;
 117                 s->mv[0][0][0] = 0;
 118                 s->mv[0][0][1] = 0;
 119                 s->mb_skipped = 1;
 120                 *mb_type_ptr = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 121                 return 0;
 122             }
 123         }
 124
 125         if(s->msmpeg4_version==2)
 126             code = get_vlc2(&s->gb, v2_mb_type_vlc.table, V2_MB_TYPE_VLC_BITS, 1);
 127         else
 128             code = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
 129         if(code<0 || code>7){
 130             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", code, s->mb_x, s->mb_y);
 131             return -1;
 132         }
 133
 134         s->mb_intra = code >>2;
 135
 136         cbp = code & 0x3;
 137     } else {
 138         s->mb_intra = 1;
 139         if(s->msmpeg4_version==2)
 140             cbp= get_vlc2(&s->gb, v2_intra_cbpc_vlc.table, V2_INTRA_CBPC_VLC_BITS, 1);
 141         else
 142             cbp= get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 1);
 143         if(cbp<0 || cbp>3){
 144             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
 145             return -1;
 146         }
 147     }
 148
 149     if (!s->mb_intra) {
 150         int mx, my, cbpy;
 151
 152         cbpy= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
 153         if(cbpy<0){
 154             av_log(s->avctx, AV_LOG_ERROR, "cbpy %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
 155             return -1;
 156         }
 157
 158         cbp|= cbpy<<2;
 159         if(s->msmpeg4_version==1 || (cbp&3) != 3) cbp^= 0x3C;
 160
 161         ff_h263_pred_motion(s, 0, 0, &mx, &my);
 162         mx= msmpeg4v2_decode_motion(s, mx, 1);
 163         my= msmpeg4v2_decode_motion(s, my, 1);
 164
 165         s->mv_dir = MV_DIR_FORWARD;
 166         s->mv_type = MV_TYPE_16X16;
 167         s->mv[0][0][0] = mx;
 168         s->mv[0][0][1] = my;
 169         *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16;
 170     } else {
 171         if(s->msmpeg4_version==2){
 172             s->ac_pred = get_bits1(&s->gb);
 173             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
 174         } else{
 175             s->ac_pred = 0;
 176             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
 177             if(s->pict_type==AV_PICTURE_TYPE_P) cbp^=0x3C;
 178         }
 179         *mb_type_ptr = MB_TYPE_INTRA;
 180     }
 181
 182     s->bdsp.clear_blocks(s->block[0]);
 183     for (i = 0; i < 6; i++) {
 184         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
 185         {
 186              av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
 187              return -1;
 188         }
 189     }
 190     return 0;
 191 }
 192
 193 static int msmpeg4v34_decode_mb(MpegEncContext *s, int16_t block[6][64])
 194 {
 195     int cbp, code, i;
 196     uint8_t *coded_val;
 197     uint32_t * const mb_type_ptr = &s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride];
 198
 199     if (s->pict_type == AV_PICTURE_TYPE_P) {
 200         if (s->use_skip_mb_code) {
 201             if (get_bits1(&s->gb)) {
 202                 /* skip mb */
 203                 s->mb_intra = 0;
 204                 for(i=0;i<6;i++)
 205                     s->block_last_index[i] = -1;
 206                 s->mv_dir = MV_DIR_FORWARD;
 207                 s->mv_type = MV_TYPE_16X16;
 208                 s->mv[0][0][0] = 0;
 209                 s->mv[0][0][1] = 0;
 210                 s->mb_skipped = 1;
 211                 *mb_type_ptr = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 212
 213                 return 0;
 214             }
 215         }
 216
 217         code = get_vlc2(&s->gb, ff_mb_non_intra_vlc[DEFAULT_INTER_INDEX].table, MB_NON_INTRA_VLC_BITS, 3);
 218         if (code < 0)
 219             return -1;
 220         //s->mb_intra = (code & 0x40) ? 0 : 1;
 221         s->mb_intra = (~code & 0x40) >> 6;
 222
 223         cbp = code & 0x3f;
 224     } else {
 225         s->mb_intra = 1;
 226         code = get_vlc2(&s->gb, ff_msmp4_mb_i_vlc.table, MB_INTRA_VLC_BITS, 2);
 227         if (code < 0)
 228             return -1;
 229         /* predict coded block pattern */
 230         cbp = 0;
 231         for(i=0;i<6;i++) {
 232             int val = ((code >> (5 - i)) & 1);
 233             if (i < 4) {
 234                 int pred = ff_msmpeg4_coded_block_pred(s, i, &coded_val);
 235                 val = val ^ pred;
 236                 *coded_val = val;
 237             }
 238             cbp |= val << (5 - i);
 239         }
 240     }
 241
 242     if (!s->mb_intra) {
 243         int mx, my;
 244         if(s->per_mb_rl_table && cbp){
 245             s->rl_table_index = decode012(&s->gb);
 246             s->rl_chroma_table_index = s->rl_table_index;
 247         }
 248         ff_h263_pred_motion(s, 0, 0, &mx, &my);
 249         if (ff_msmpeg4_decode_motion(s, &mx, &my) < 0)
 250             return -1;
 251         s->mv_dir = MV_DIR_FORWARD;
 252         s->mv_type = MV_TYPE_16X16;
 253         s->mv[0][0][0] = mx;
 254         s->mv[0][0][1] = my;
 255         *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16;
 256     } else {
 257         av_dlog(s, "I at %d %d %d %06X\n", s->mb_x, s->mb_y,
 258                 ((cbp & 3) ? 1 : 0) +((cbp & 0x3C)? 2 : 0),
 259                 show_bits(&s->gb, 24));
 260         s->ac_pred = get_bits1(&s->gb);
 261         *mb_type_ptr = MB_TYPE_INTRA;
 262         if(s->inter_intra_pred){
 263             s->h263_aic_dir= get_vlc2(&s->gb, ff_inter_intra_vlc.table, INTER_INTRA_VLC_BITS, 1);
 264             av_dlog(s, "%d%d %d %d/",
 265                     s->ac_pred, s->h263_aic_dir, s->mb_x, s->mb_y);
 266         }
 267         if(s->per_mb_rl_table && cbp){
 268             s->rl_table_index = decode012(&s->gb);
 269             s->rl_chroma_table_index = s->rl_table_index;
 270         }
 271     }
 272
 273     s->bdsp.clear_blocks(s->block[0]);
 274     for (i = 0; i < 6; i++) {
 275         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
 276         {
 277             av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
 278             return -1;
 279         }
 280     }
 281
 282     return 0;
 283 }
 284
 285 /* init all vlc decoding tables */
 286 av_cold int ff_msmpeg4_decode_init(AVCodecContext *avctx)
 287 {
 288     MpegEncContext *s = avctx->priv_data;
 289     static volatile int done = 0;
 290     int i, ret;
 291     MVTable *mv;
 292
 293     if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
 294         return ret;
 295
 296     if (ff_h263_decode_init(avctx) < 0)
 297         return -1;
 298
 299     ff_msmpeg4_common_init(s);
 300
 301     if (!done) {
 302         for(i=0;i<NB_RL_TABLES;i++) {
 303             ff_init_rl(&ff_rl_table[i], ff_static_rl_table_store[i]);
 304         }
 305         INIT_VLC_RL(ff_rl_table[0], 642);
 306         INIT_VLC_RL(ff_rl_table[1], 1104);
 307         INIT_VLC_RL(ff_rl_table[2], 554);
 308         INIT_VLC_RL(ff_rl_table[3], 940);
 309         INIT_VLC_RL(ff_rl_table[4], 962);
 310         INIT_VLC_RL(ff_rl_table[5], 554);
 311
 312         mv = &ff_mv_tables[0];
 313         INIT_VLC_STATIC(&mv->vlc, MV_VLC_BITS, mv->n + 1,
 314                     mv->table_mv_bits, 1, 1,
 315                     mv->table_mv_code, 2, 2, 3714);
 316         mv = &ff_mv_tables[1];
 317         INIT_VLC_STATIC(&mv->vlc, MV_VLC_BITS, mv->n + 1,
 318                     mv->table_mv_bits, 1, 1,
 319                     mv->table_mv_code, 2, 2, 2694);
 320
 321         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[0], DC_VLC_BITS, 120,
 322                  &ff_table0_dc_lum[0][1], 8, 4,
 323                  &ff_table0_dc_lum[0][0], 8, 4, 1158);
 324         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[0], DC_VLC_BITS, 120,
 325                  &ff_table0_dc_chroma[0][1], 8, 4,
 326                  &ff_table0_dc_chroma[0][0], 8, 4, 1118);
 327         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[1], DC_VLC_BITS, 120,
 328                  &ff_table1_dc_lum[0][1], 8, 4,
 329                  &ff_table1_dc_lum[0][0], 8, 4, 1476);
 330         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[1], DC_VLC_BITS, 120,
 331                  &ff_table1_dc_chroma[0][1], 8, 4,
 332                  &ff_table1_dc_chroma[0][0], 8, 4, 1216);
 333
 334         INIT_VLC_STATIC(&v2_dc_lum_vlc, DC_VLC_BITS, 512,
 335                  &ff_v2_dc_lum_table[0][1], 8, 4,
 336                  &ff_v2_dc_lum_table[0][0], 8, 4, 1472);
 337         INIT_VLC_STATIC(&v2_dc_chroma_vlc, DC_VLC_BITS, 512,
 338                  &ff_v2_dc_chroma_table[0][1], 8, 4,
 339                  &ff_v2_dc_chroma_table[0][0], 8, 4, 1506);
 340
 341         INIT_VLC_STATIC(&v2_intra_cbpc_vlc, V2_INTRA_CBPC_VLC_BITS, 4,
 342                  &ff_v2_intra_cbpc[0][1], 2, 1,
 343                  &ff_v2_intra_cbpc[0][0], 2, 1, 8);
 344         INIT_VLC_STATIC(&v2_mb_type_vlc, V2_MB_TYPE_VLC_BITS, 8,
 345                  &ff_v2_mb_type[0][1], 2, 1,
 346                  &ff_v2_mb_type[0][0], 2, 1, 128);
 347         INIT_VLC_STATIC(&v2_mv_vlc, V2_MV_VLC_BITS, 33,
 348                  &ff_mvtab[0][1], 2, 1,
 349                  &ff_mvtab[0][0], 2, 1, 538);
 350
 351         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[0], MB_NON_INTRA_VLC_BITS, 128,
 352                      &ff_wmv2_inter_table[0][0][1], 8, 4,
 353                      &ff_wmv2_inter_table[0][0][0], 8, 4, 1636);
 354         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[1], MB_NON_INTRA_VLC_BITS, 128,
 355                      &ff_wmv2_inter_table[1][0][1], 8, 4,
 356                      &ff_wmv2_inter_table[1][0][0], 8, 4, 2648);
 357         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[2], MB_NON_INTRA_VLC_BITS, 128,
 358                      &ff_wmv2_inter_table[2][0][1], 8, 4,
 359                      &ff_wmv2_inter_table[2][0][0], 8, 4, 1532);
 360         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[3], MB_NON_INTRA_VLC_BITS, 128,
 361                      &ff_wmv2_inter_table[3][0][1], 8, 4,
 362                      &ff_wmv2_inter_table[3][0][0], 8, 4, 2488);
 363
 364         INIT_VLC_STATIC(&ff_msmp4_mb_i_vlc, MB_INTRA_VLC_BITS, 64,
 365                  &ff_msmp4_mb_i_table[0][1], 4, 2,
 366                  &ff_msmp4_mb_i_table[0][0], 4, 2, 536);
 367
 368         INIT_VLC_STATIC(&ff_inter_intra_vlc, INTER_INTRA_VLC_BITS, 4,
 369                  &ff_table_inter_intra[0][1], 2, 1,
 370                  &ff_table_inter_intra[0][0], 2, 1, 8);
 371         done = 1;
 372     }
 373
 374     switch(s->msmpeg4_version){
 375     case 1:
 376     case 2:
 377         s->decode_mb= msmpeg4v12_decode_mb;
 378         break;
 379     case 3:
 380     case 4:
 381         s->decode_mb= msmpeg4v34_decode_mb;
 382         break;
 383     case 5:
 384         if (CONFIG_WMV2_DECODER)
 385             s->decode_mb= ff_wmv2_decode_mb;
 386     case 6:
 387         //FIXME + TODO VC1 decode mb
 388         break;
 389     }
 390
 391     s->slice_height= s->mb_height; //to avoid 1/0 if the first frame is not a keyframe
 392
 393     return 0;
 394 }
 395
 396 int ff_msmpeg4_decode_picture_header(MpegEncContext * s)
 397 {
 398     int code;
 399
 400     if(s->msmpeg4_version==1){
 401         int start_code = get_bits_long(&s->gb, 32);
 402         if(start_code!=0x00000100){
 403             av_log(s->avctx, AV_LOG_ERROR, "invalid startcode\n");
 404             return -1;
 405         }
 406
 407         skip_bits(&s->gb, 5); // frame number */
 408     }
 409
 410     s->pict_type = get_bits(&s->gb, 2) + 1;
 411     if (s->pict_type != AV_PICTURE_TYPE_I &&
 412         s->pict_type != AV_PICTURE_TYPE_P){
 413         av_log(s->avctx, AV_LOG_ERROR, "invalid picture type\n");
 414         return -1;
 415     }
 416 #if 0
 417 {
 418     static int had_i=0;
 419     if(s->pict_type == AV_PICTURE_TYPE_I) had_i=1;
 420     if(!had_i) return -1;
 421 }
 422 #endif
 423     s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
 424     if(s->qscale==0){
 425         av_log(s->avctx, AV_LOG_ERROR, "invalid qscale\n");
 426         return -1;
 427     }
 428
 429     if (s->pict_type == AV_PICTURE_TYPE_I) {
 430         code = get_bits(&s->gb, 5);
 431         if(s->msmpeg4_version==1){
 432             if(code==0 || code>s->mb_height){
 433                 av_log(s->avctx, AV_LOG_ERROR, "invalid slice height %d\n", code);
 434                 return -1;
 435             }
 436
 437             s->slice_height = code;
 438         }else{
 439             /* 0x17: one slice, 0x18: two slices, ... */
 440             if (code < 0x17){
 441                 av_log(s->avctx, AV_LOG_ERROR, "error, slice code was %X\n", code);
 442                 return -1;
 443             }
 444
 445             s->slice_height = s->mb_height / (code - 0x16);
 446         }
 447
 448         switch(s->msmpeg4_version){
 449         case 1:
 450         case 2:
 451             s->rl_chroma_table_index = 2;
 452             s->rl_table_index = 2;
 453
 454             s->dc_table_index = 0; //not used
 455             break;
 456         case 3:
 457             s->rl_chroma_table_index = decode012(&s->gb);
 458             s->rl_table_index = decode012(&s->gb);
 459
 460             s->dc_table_index = get_bits1(&s->gb);
 461             break;
 462         case 4:
 463             ff_msmpeg4_decode_ext_header(s, (2+5+5+17+7)/8);
 464
 465             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
 466             else                           s->per_mb_rl_table= 0;
 467
 468             if(!s->per_mb_rl_table){
 469                 s->rl_chroma_table_index = decode012(&s->gb);
 470                 s->rl_table_index = decode012(&s->gb);
 471             }
 472
 473             s->dc_table_index = get_bits1(&s->gb);
 474             s->inter_intra_pred= 0;
 475             break;
 476         }
 477         s->no_rounding = 1;
 478         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
 479             av_log(s->avctx, AV_LOG_DEBUG, "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d slice:%d   \n",
 480                 s->qscale,
 481                 s->rl_chroma_table_index,
 482                 s->rl_table_index,
 483                 s->dc_table_index,
 484                 s->per_mb_rl_table,
 485                 s->slice_height);
 486     } else {
 487         switch(s->msmpeg4_version){
 488         case 1:
 489         case 2:
 490             if(s->msmpeg4_version==1)
 491                 s->use_skip_mb_code = 1;
 492             else
 493                 s->use_skip_mb_code = get_bits1(&s->gb);
 494             s->rl_table_index = 2;
 495             s->rl_chroma_table_index = s->rl_table_index;
 496             s->dc_table_index = 0; //not used
 497             s->mv_table_index = 0;
 498             break;
 499         case 3:
 500             s->use_skip_mb_code = get_bits1(&s->gb);
 501             s->rl_table_index = decode012(&s->gb);
 502             s->rl_chroma_table_index = s->rl_table_index;
 503
 504             s->dc_table_index = get_bits1(&s->gb);
 505
 506             s->mv_table_index = get_bits1(&s->gb);
 507             break;
 508         case 4:
 509             s->use_skip_mb_code = get_bits1(&s->gb);
 510
 511             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
 512             else                           s->per_mb_rl_table= 0;
 513
 514             if(!s->per_mb_rl_table){
 515                 s->rl_table_index = decode012(&s->gb);
 516                 s->rl_chroma_table_index = s->rl_table_index;
 517             }
 518
 519             s->dc_table_index = get_bits1(&s->gb);
 520
 521             s->mv_table_index = get_bits1(&s->gb);
 522             s->inter_intra_pred= (s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE);
 523             break;
 524         }
 525
 526         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
 527             av_log(s->avctx, AV_LOG_DEBUG, "skip:%d rl:%d rlc:%d dc:%d mv:%d mbrl:%d qp:%d   \n",
 528                 s->use_skip_mb_code,
 529                 s->rl_table_index,
 530                 s->rl_chroma_table_index,
 531                 s->dc_table_index,
 532                 s->mv_table_index,
 533                 s->per_mb_rl_table,
 534                 s->qscale);
 535
 536         if(s->flipflop_rounding){
 537             s->no_rounding ^= 1;
 538         }else{
 539             s->no_rounding = 0;
 540         }
 541     }
 542     av_dlog(s->avctx, "%d %d %d %d %d\n", s->pict_type, s->bit_rate,
 543             s->inter_intra_pred, s->width, s->height);
 544
 545     s->esc3_level_length= 0;
 546     s->esc3_run_length= 0;
 547
 548     return 0;
 549 }
 550
 551 int ff_msmpeg4_decode_ext_header(MpegEncContext * s, int buf_size)
 552 {
 553     int left= buf_size*8 - get_bits_count(&s->gb);
 554     int length= s->msmpeg4_version>=3 ? 17 : 16;
 555     /* the alt_bitstream reader could read over the end so we need to check it */
 556     if(left>=length && left<length+8)
 557     {
 558         skip_bits(&s->gb, 5); /* fps */
 559         s->bit_rate= get_bits(&s->gb, 11)*1024;
 560         if(s->msmpeg4_version>=3)
 561             s->flipflop_rounding= get_bits1(&s->gb);
 562         else
 563             s->flipflop_rounding= 0;
 564     }
 565     else if(left<length+8)
 566     {
 567         s->flipflop_rounding= 0;
 568         if(s->msmpeg4_version != 2)
 569             av_log(s->avctx, AV_LOG_ERROR, "ext header missing, %d left\n", left);
 570     }
 571     else
 572     {
 573         av_log(s->avctx, AV_LOG_ERROR, "I frame too long, ignoring ext header\n");
 574     }
 575
 576     return 0;
 577 }
 578
 579 static int msmpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
 580 {
 581     int level, pred;
 582
 583     if(s->msmpeg4_version<=2){
 584         if (n < 4) {
 585             level = get_vlc2(&s->gb, v2_dc_lum_vlc.table, DC_VLC_BITS, 3);
 586         } else {
 587             level = get_vlc2(&s->gb, v2_dc_chroma_vlc.table, DC_VLC_BITS, 3);
 588         }
 589         if (level < 0) {
 590             av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
 591             *dir_ptr = 0;
 592             return -1;
 593         }
 594         level-=256;
 595     }else{  //FIXME optimize use unified tables & index
 596         if (n < 4) {
 597             level = get_vlc2(&s->gb, ff_msmp4_dc_luma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
 598         } else {
 599             level = get_vlc2(&s->gb, ff_msmp4_dc_chroma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
 600         }
 601         if (level < 0){
 602             av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
 603             *dir_ptr = 0;
 604             return -1;
 605         }
 606
 607         if (level == DC_MAX) {
 608             level = get_bits(&s->gb, 8);
 609             if (get_bits1(&s->gb))
 610                 level = -level;
 611         } else if (level != 0) {
 612             if (get_bits1(&s->gb))
 613                 level = -level;
 614         }
 615     }
 616
 617     if(s->msmpeg4_version==1){
 618         int32_t *dc_val;
 619         pred = msmpeg4v1_pred_dc(s, n, &dc_val);
 620         level += pred;
 621
 622         /* update predictor */
 623         *dc_val= level;
 624     }else{
 625         int16_t *dc_val;
 626         pred   = ff_msmpeg4_pred_dc(s, n, &dc_val, dir_ptr);
 627         level += pred;
 628
 629         /* update predictor */
 630         if (n < 4) {
 631             *dc_val = level * s->y_dc_scale;
 632         } else {
 633             *dc_val = level * s->c_dc_scale;
 634         }
 635     }
 636
 637     return level;
 638 }
 639
 640 //#define ERROR_DETAILS
 641 int ff_msmpeg4_decode_block(MpegEncContext * s, int16_t * block,
 642                               int n, int coded, const uint8_t *scan_table)
 643 {
 644     int level, i, last, run, run_diff;
 645     int av_uninit(dc_pred_dir);
 646     RLTable *rl;
 647     RL_VLC_ELEM *rl_vlc;
 648     int qmul, qadd;
 649
 650     if (s->mb_intra) {
 651         qmul=1;
 652         qadd=0;
 653
 654         /* DC coef */
 655         level = msmpeg4_decode_dc(s, n, &dc_pred_dir);
 656
 657         if (level < 0){
 658             av_log(s->avctx, AV_LOG_ERROR, "dc overflow- block: %d qscale: %d//\n", n, s->qscale);
 659             if(s->inter_intra_pred) level=0;
 660         }
 661         if (n < 4) {
 662             rl = &ff_rl_table[s->rl_table_index];
 663             if(level > 256*s->y_dc_scale){
 664                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ L qscale: %d//\n", s->qscale);
 665                 if(!s->inter_intra_pred) return -1;
 666             }
 667         } else {
 668             rl = &ff_rl_table[3 + s->rl_chroma_table_index];
 669             if(level > 256*s->c_dc_scale){
 670                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ C qscale: %d//\n", s->qscale);
 671                 if(!s->inter_intra_pred) return -1;
 672             }
 673         }
 674         block[0] = level;
 675
 676         run_diff = s->msmpeg4_version >= 4;
 677         i = 0;
 678         if (!coded) {
 679             goto not_coded;
 680         }
 681         if (s->ac_pred) {
 682             if (dc_pred_dir == 0)
 683                 scan_table = s->intra_v_scantable.permutated; /* left */
 684             else
 685                 scan_table = s->intra_h_scantable.permutated; /* top */
 686         } else {
 687             scan_table = s->intra_scantable.permutated;
 688         }
 689         rl_vlc= rl->rl_vlc[0];
 690     } else {
 691         qmul = s->qscale << 1;
 692         qadd = (s->qscale - 1) | 1;
 693         i = -1;
 694         rl = &ff_rl_table[3 + s->rl_table_index];
 695
 696         if(s->msmpeg4_version==2)
 697             run_diff = 0;
 698         else
 699             run_diff = 1;
 700
 701         if (!coded) {
 702             s->block_last_index[n] = i;
 703             return 0;
 704         }
 705         if(!scan_table)
 706             scan_table = s->inter_scantable.permutated;
 707         rl_vlc= rl->rl_vlc[s->qscale];
 708     }
 709   {
 710     OPEN_READER(re, &s->gb);
 711     for(;;) {
 712         UPDATE_CACHE(re, &s->gb);
 713         GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
 714         if (level==0) {
 715             int cache;
 716             cache= GET_CACHE(re, &s->gb);
 717             /* escape */
 718             if (s->msmpeg4_version==1 || (cache&0x80000000)==0) {
 719                 if (s->msmpeg4_version==1 || (cache&0x40000000)==0) {
 720                     /* third escape */
 721                     if(s->msmpeg4_version!=1) LAST_SKIP_BITS(re, &s->gb, 2);
 722                     UPDATE_CACHE(re, &s->gb);
 723                     if(s->msmpeg4_version<=3){
 724                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
 725                         run=   SHOW_UBITS(re, &s->gb, 6); SKIP_CACHE(re, &s->gb, 6);
 726                         level= SHOW_SBITS(re, &s->gb, 8);
 727                         SKIP_COUNTER(re, &s->gb, 1+6+8);
 728                     }else{
 729                         int sign;
 730                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
 731                         if(!s->esc3_level_length){
 732                             int ll;
 733                             av_dlog(s->avctx, "ESC-3 %X at %d %d\n",
 734                                     show_bits(&s->gb, 24), s->mb_x, s->mb_y);
 735                             if(s->qscale<8){
 736                                 ll= SHOW_UBITS(re, &s->gb, 3); SKIP_BITS(re, &s->gb, 3);
 737                                 if(ll==0){
 738                                     ll= 8+SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
 739                                 }
 740                             }else{
 741                                 ll=2;
 742                                 while(ll<8 && SHOW_UBITS(re, &s->gb, 1)==0){
 743                                     ll++;
 744                                     SKIP_BITS(re, &s->gb, 1);
 745                                 }
 746                                 if(ll<8) SKIP_BITS(re, &s->gb, 1);
 747                             }
 748
 749                             s->esc3_level_length= ll;
 750                             s->esc3_run_length= SHOW_UBITS(re, &s->gb, 2) + 3; SKIP_BITS(re, &s->gb, 2);
 751                             UPDATE_CACHE(re, &s->gb);
 752                         }
 753                         run=   SHOW_UBITS(re, &s->gb, s->esc3_run_length);
 754                         SKIP_BITS(re, &s->gb, s->esc3_run_length);
 755
 756                         sign=  SHOW_UBITS(re, &s->gb, 1);
 757                         SKIP_BITS(re, &s->gb, 1);
 758
 759                         level= SHOW_UBITS(re, &s->gb, s->esc3_level_length);
 760                         SKIP_BITS(re, &s->gb, s->esc3_level_length);
 761                         if(sign) level= -level;
 762                     }
 763
 764 #if 0 // waste of time / this will detect very few errors
 765                     {
 766                         const int abs_level= FFABS(level);
 767                         const int run1= run - rl->max_run[last][abs_level] - run_diff;
 768                         if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
 769                             if(abs_level <= rl->max_level[last][run]){
 770                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
 771                                 return DECODING_AC_LOST;
 772                             }
 773                             if(abs_level <= rl->max_level[last][run]*2){
 774                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
 775                                 return DECODING_AC_LOST;
 776                             }
 777                             if(run1>=0 && abs_level <= rl->max_level[last][run1]){
 778                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
 779                                 return DECODING_AC_LOST;
 780                             }
 781                         }
 782                     }
 783 #endif
 784                     //level = level * qmul + (level>0) * qadd - (level<=0) * qadd ;
 785                     if (level>0) level= level * qmul + qadd;
 786                     else         level= level * qmul - qadd;
 787 #if 0 // waste of time too :(
 788                     if(level>2048 || level<-2048){
 789                         av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc\n");
 790                         return DECODING_AC_LOST;
 791                     }
 792 #endif
 793                     i+= run + 1;
 794                     if(last) i+=192;
 795 #ifdef ERROR_DETAILS
 796                 if(run==66)
 797                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC3 level=%d\n", level);
 798                 else if((i>62 && i<192) || i>192+63)
 799                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC3 i=%d run=%d level=%d\n", i, run, level);
 800 #endif
 801                 } else {
 802                     /* second escape */
 803                     SKIP_BITS(re, &s->gb, 2);
 804                     GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
 805                     i+= run + rl->max_run[run>>7][level/qmul] + run_diff; //FIXME opt indexing
 806                     level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 807                     LAST_SKIP_BITS(re, &s->gb, 1);
 808 #ifdef ERROR_DETAILS
 809                 if(run==66)
 810                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC2 level=%d\n", level);
 811                 else if((i>62 && i<192) || i>192+63)
 812                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC2 i=%d run=%d level=%d\n", i, run, level);
 813 #endif
 814                 }
 815             } else {
 816                 /* first escape */
 817                 SKIP_BITS(re, &s->gb, 1);
 818                 GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
 819                 i+= run;
 820                 level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
 821                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 822                 LAST_SKIP_BITS(re, &s->gb, 1);
 823 #ifdef ERROR_DETAILS
 824                 if(run==66)
 825                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC1 level=%d\n", level);
 826                 else if((i>62 && i<192) || i>192+63)
 827                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC1 i=%d run=%d level=%d\n", i, run, level);
 828 #endif
 829             }
 830         } else {
 831             i+= run;
 832             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 833             LAST_SKIP_BITS(re, &s->gb, 1);
 834 #ifdef ERROR_DETAILS
 835                 if(run==66)
 836                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code level=%d\n", level);
 837                 else if((i>62 && i<192) || i>192+63)
 838                     av_log(s->avctx, AV_LOG_ERROR, "run overflow i=%d run=%d level=%d\n", i, run, level);
 839 #endif
 840         }
 841         if (i > 62){
 842             i-= 192;
 843             if(i&(~63)){
 844                 const int left= get_bits_left(&s->gb);
 845                 if(((i+192 == 64 && level/qmul==-1) || !(s->err_recognition&(AV_EF_BITSTREAM|AV_EF_COMPLIANT))) && left>=0){
 846                     av_log(s->avctx, AV_LOG_ERROR, "ignoring overflow at %d %d\n", s->mb_x, s->mb_y);
 847                     i = 63;
 848                     break;
 849                 }else{
 850                     av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 851                     return -1;
 852                 }
 853             }
 854
 855             block[scan_table[i]] = level;
 856             break;
 857         }
 858
 859         block[scan_table[i]] = level;
 860     }
 861     CLOSE_READER(re, &s->gb);
 862   }
 863  not_coded:
 864     if (s->mb_intra) {
 865         ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
 866         if (s->ac_pred) {
 867             i = 63; /* XXX: not optimal */
 868         }
 869     }
 870     if(s->msmpeg4_version>=4 && i>0) i=63; //FIXME/XXX optimize
 871     s->block_last_index[n] = i;
 872
 873     return 0;
 874 }
 875
 876 int ff_msmpeg4_decode_motion(MpegEncContext * s,
 877                                  int *mx_ptr, int *my_ptr)
 878 {
 879     MVTable *mv;
 880     int code, mx, my;
 881
 882     mv = &ff_mv_tables[s->mv_table_index];
 883
 884     code = get_vlc2(&s->gb, mv->vlc.table, MV_VLC_BITS, 2);
 885     if (code < 0){
 886         av_log(s->avctx, AV_LOG_ERROR, "illegal MV code at %d %d\n", s->mb_x, s->mb_y);
 887         return -1;
 888     }
 889     if (code == mv->n) {
 890         mx = get_bits(&s->gb, 6);
 891         my = get_bits(&s->gb, 6);
 892     } else {
 893         mx = mv->table_mvx[code];
 894         my = mv->table_mvy[code];
 895     }
 896
 897     mx += *mx_ptr - 32;
 898     my += *my_ptr - 32;
 899     /* WARNING : they do not do exactly modulo encoding */
 900     if (mx <= -64)
 901         mx += 64;
 902     else if (mx >= 64)
 903         mx -= 64;
 904
 905     if (my <= -64)
 906         my += 64;
 907     else if (my >= 64)
 908         my -= 64;
 909     *mx_ptr = mx;
 910     *my_ptr = my;
 911     return 0;
 912 }
 913
 914 AVCodec ff_msmpeg4v1_decoder = {
 915     .name           = "msmpeg4v1",
 916     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 1"),
 917     .type           = AVMEDIA_TYPE_VIDEO,
 918     .id             = AV_CODEC_ID_MSMPEG4V1,
 919     .priv_data_size = sizeof(MpegEncContext),
 920     .init           = ff_msmpeg4_decode_init,
 921     .close          = ff_h263_decode_end,
 922     .decode         = ff_h263_decode_frame,
 923     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 924     .max_lowres     = 3,
 925     .pix_fmts       = (const enum AVPixelFormat[]) {
 926         AV_PIX_FMT_YUV420P,
 927         AV_PIX_FMT_NONE
 928     },
 929 };
 930
 931 AVCodec ff_msmpeg4v2_decoder = {
 932     .name           = "msmpeg4v2",
 933     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 2"),
 934     .type           = AVMEDIA_TYPE_VIDEO,
 935     .id             = AV_CODEC_ID_MSMPEG4V2,
 936     .priv_data_size = sizeof(MpegEncContext),
 937     .init           = ff_msmpeg4_decode_init,
 938     .close          = ff_h263_decode_end,
 939     .decode         = ff_h263_decode_frame,
 940     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 941     .max_lowres     = 3,
 942     .pix_fmts       = (const enum AVPixelFormat[]) {
 943         AV_PIX_FMT_YUV420P,
 944         AV_PIX_FMT_NONE
 945     },
 946 };
 947
 948 AVCodec ff_msmpeg4v3_decoder = {
 949     .name           = "msmpeg4",
 950     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 3"),
 951     .type           = AVMEDIA_TYPE_VIDEO,
 952     .id             = AV_CODEC_ID_MSMPEG4V3,
 953     .priv_data_size = sizeof(MpegEncContext),
 954     .init           = ff_msmpeg4_decode_init,
 955     .close          = ff_h263_decode_end,
 956     .decode         = ff_h263_decode_frame,
 957     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 958     .max_lowres     = 3,
 959     .pix_fmts       = (const enum AVPixelFormat[]) {
 960         AV_PIX_FMT_YUV420P,
 961         AV_PIX_FMT_NONE
 962     },
 963 };
 964
 965 AVCodec ff_wmv1_decoder = {
 966     .name           = "wmv1",
 967     .long_name      = NULL_IF_CONFIG_SMALL("Windows Media Video 7"),
 968     .type           = AVMEDIA_TYPE_VIDEO,
 969     .id             = AV_CODEC_ID_WMV1,
 970     .priv_data_size = sizeof(MpegEncContext),
 971     .init           = ff_msmpeg4_decode_init,
 972     .close          = ff_h263_decode_end,
 973     .decode         = ff_h263_decode_frame,
 974     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
 975     .max_lowres     = 3,
 976     .pix_fmts       = (const enum AVPixelFormat[]) {
 977         AV_PIX_FMT_YUV420P,
 978         AV_PIX_FMT_NONE
 979     },
 980 };