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 "libavutil/x86/asm.h"
  31 #include "h263.h"
  32 #include "mpeg4video.h"
  33 #include "msmpeg4data.h"
  34 #include "vc1data.h"
  35 #include "wmv2.h"
  36
  37 #define DC_VLC_BITS 9
  38 #define V2_INTRA_CBPC_VLC_BITS 3
  39 #define V2_MB_TYPE_VLC_BITS 7
  40 #define MV_VLC_BITS 9
  41 #define V2_MV_VLC_BITS 9
  42 #define TEX_VLC_BITS 9
  43
  44 #define DEFAULT_INTER_INDEX 3
  45
  46 static inline int msmpeg4v1_pred_dc(MpegEncContext * s, int n,
  47                                     int32_t **dc_val_ptr)
  48 {
  49     int i;
  50
  51     if (n < 4) {
  52         i= 0;
  53     } else {
  54         i= n-3;
  55     }
  56
  57     *dc_val_ptr= &s->last_dc[i];
  58     return s->last_dc[i];
  59 }
  60
  61 /****************************************/
  62 /* decoding stuff */
  63
  64 VLC ff_mb_non_intra_vlc[4];
  65 static VLC v2_dc_lum_vlc;
  66 static VLC v2_dc_chroma_vlc;
  67 static VLC v2_intra_cbpc_vlc;
  68 static VLC v2_mb_type_vlc;
  69 static VLC v2_mv_vlc;
  70 VLC ff_inter_intra_vlc;
  71
  72 /* This is identical to H.263 except that its range is multiplied by 2. */
  73 static int msmpeg4v2_decode_motion(MpegEncContext * s, int pred, int f_code)
  74 {
  75     int code, val, sign, shift;
  76
  77     code = get_vlc2(&s->gb, v2_mv_vlc.table, V2_MV_VLC_BITS, 2);
  78     ff_dlog(s, "MV code %d at %d %d pred: %d\n", code, s->mb_x,s->mb_y, pred);
  79     if (code < 0)
  80         return 0xffff;
  81
  82     if (code == 0)
  83         return pred;
  84     sign = get_bits1(&s->gb);
  85     shift = f_code - 1;
  86     val = code;
  87     if (shift) {
  88         val = (val - 1) << shift;
  89         val |= get_bits(&s->gb, shift);
  90         val++;
  91     }
  92     if (sign)
  93         val = -val;
  94
  95     val += pred;
  96     if (val <= -64)
  97         val += 64;
  98     else if (val >= 64)
  99         val -= 64;
 100
 101     return val;
 102 }
 103
 104 static int msmpeg4v12_decode_mb(MpegEncContext *s, int16_t block[6][64])
 105 {
 106     int cbp, code, i;
 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                 return 0;
 121             }
 122         }
 123
 124         if(s->msmpeg4_version==2)
 125             code = get_vlc2(&s->gb, v2_mb_type_vlc.table, V2_MB_TYPE_VLC_BITS, 1);
 126         else
 127             code = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
 128         if(code<0 || code>7){
 129             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", code, s->mb_x, s->mb_y);
 130             return -1;
 131         }
 132
 133         s->mb_intra = code >>2;
 134
 135         cbp = code & 0x3;
 136     } else {
 137         s->mb_intra = 1;
 138         if(s->msmpeg4_version==2)
 139             cbp= get_vlc2(&s->gb, v2_intra_cbpc_vlc.table, V2_INTRA_CBPC_VLC_BITS, 1);
 140         else
 141             cbp= get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 1);
 142         if(cbp<0 || cbp>3){
 143             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
 144             return -1;
 145         }
 146     }
 147
 148     if (!s->mb_intra) {
 149         int mx, my, cbpy;
 150
 151         cbpy= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
 152         if(cbpy<0){
 153             av_log(s->avctx, AV_LOG_ERROR, "cbpy %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
 154             return -1;
 155         }
 156
 157         cbp|= cbpy<<2;
 158         if(s->msmpeg4_version==1 || (cbp&3) != 3) cbp^= 0x3C;
 159
 160         ff_h263_pred_motion(s, 0, 0, &mx, &my);
 161         mx= msmpeg4v2_decode_motion(s, mx, 1);
 162         my= msmpeg4v2_decode_motion(s, my, 1);
 163
 164         s->mv_dir = MV_DIR_FORWARD;
 165         s->mv_type = MV_TYPE_16X16;
 166         s->mv[0][0][0] = mx;
 167         s->mv[0][0][1] = my;
 168     } else {
 169         if(s->msmpeg4_version==2){
 170             s->ac_pred = get_bits1(&s->gb);
 171             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
 172         } else{
 173             s->ac_pred = 0;
 174             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
 175             if(s->pict_type==AV_PICTURE_TYPE_P) cbp^=0x3C;
 176         }
 177     }
 178
 179     s->bdsp.clear_blocks(s->block[0]);
 180     for (i = 0; i < 6; i++) {
 181         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
 182         {
 183              av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
 184              return -1;
 185         }
 186     }
 187     return 0;
 188 }
 189
 190 static int msmpeg4v34_decode_mb(MpegEncContext *s, int16_t block[6][64])
 191 {
 192     int cbp, code, i;
 193     uint8_t *coded_val;
 194     uint32_t * const mb_type_ptr = &s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride];
 195
 196     if (s->pict_type == AV_PICTURE_TYPE_P) {
 197         if (s->use_skip_mb_code) {
 198             if (get_bits1(&s->gb)) {
 199                 /* skip mb */
 200                 s->mb_intra = 0;
 201                 for(i=0;i<6;i++)
 202                     s->block_last_index[i] = -1;
 203                 s->mv_dir = MV_DIR_FORWARD;
 204                 s->mv_type = MV_TYPE_16X16;
 205                 s->mv[0][0][0] = 0;
 206                 s->mv[0][0][1] = 0;
 207                 s->mb_skipped = 1;
 208                 *mb_type_ptr = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 209
 210                 return 0;
 211             }
 212         }
 213
 214         code = get_vlc2(&s->gb, ff_mb_non_intra_vlc[DEFAULT_INTER_INDEX].table, MB_NON_INTRA_VLC_BITS, 3);
 215         if (code < 0)
 216             return -1;
 217         //s->mb_intra = (code & 0x40) ? 0 : 1;
 218         s->mb_intra = (~code & 0x40) >> 6;
 219
 220         cbp = code & 0x3f;
 221     } else {
 222         s->mb_intra = 1;
 223         code = get_vlc2(&s->gb, ff_msmp4_mb_i_vlc.table, MB_INTRA_VLC_BITS, 2);
 224         if (code < 0)
 225             return -1;
 226         /* predict coded block pattern */
 227         cbp = 0;
 228         for(i=0;i<6;i++) {
 229             int val = ((code >> (5 - i)) & 1);
 230             if (i < 4) {
 231                 int pred = ff_msmpeg4_coded_block_pred(s, i, &coded_val);
 232                 val = val ^ pred;
 233                 *coded_val = val;
 234             }
 235             cbp |= val << (5 - i);
 236         }
 237     }
 238
 239     if (!s->mb_intra) {
 240         int mx, my;
 241         if(s->per_mb_rl_table && cbp){
 242             s->rl_table_index = decode012(&s->gb);
 243             s->rl_chroma_table_index = s->rl_table_index;
 244         }
 245         ff_h263_pred_motion(s, 0, 0, &mx, &my);
 246         if (ff_msmpeg4_decode_motion(s, &mx, &my) < 0)
 247             return -1;
 248         s->mv_dir = MV_DIR_FORWARD;
 249         s->mv_type = MV_TYPE_16X16;
 250         s->mv[0][0][0] = mx;
 251         s->mv[0][0][1] = my;
 252         *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16;
 253     } else {
 254         ff_dlog(s, "I at %d %d %d %06X\n", s->mb_x, s->mb_y,
 255                 ((cbp & 3) ? 1 : 0) +((cbp & 0x3C)? 2 : 0),
 256                 show_bits(&s->gb, 24));
 257         s->ac_pred = get_bits1(&s->gb);
 258         *mb_type_ptr = MB_TYPE_INTRA;
 259         if(s->inter_intra_pred){
 260             s->h263_aic_dir= get_vlc2(&s->gb, ff_inter_intra_vlc.table, INTER_INTRA_VLC_BITS, 1);
 261             ff_dlog(s, "%d%d %d %d/",
 262                     s->ac_pred, s->h263_aic_dir, s->mb_x, s->mb_y);
 263         }
 264         if(s->per_mb_rl_table && cbp){
 265             s->rl_table_index = decode012(&s->gb);
 266             s->rl_chroma_table_index = s->rl_table_index;
 267         }
 268     }
 269
 270     s->bdsp.clear_blocks(s->block[0]);
 271     for (i = 0; i < 6; i++) {
 272         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
 273         {
 274             av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
 275             return -1;
 276         }
 277     }
 278
 279     return 0;
 280 }
 281
 282 /* init all vlc decoding tables */
 283 av_cold int ff_msmpeg4_decode_init(AVCodecContext *avctx)
 284 {
 285     MpegEncContext *s = avctx->priv_data;
 286     static int done = 0;
 287     int i;
 288     MVTable *mv;
 289
 290     if (ff_h263_decode_init(avctx) < 0)
 291         return -1;
 292
 293     ff_msmpeg4_common_init(s);
 294
 295     if (!done) {
 296         done = 1;
 297
 298         for(i=0;i<NB_RL_TABLES;i++) {
 299             ff_rl_init(&ff_rl_table[i], ff_static_rl_table_store[i]);
 300         }
 301         INIT_VLC_RL(ff_rl_table[0], 642);
 302         INIT_VLC_RL(ff_rl_table[1], 1104);
 303         INIT_VLC_RL(ff_rl_table[2], 554);
 304         INIT_VLC_RL(ff_rl_table[3], 940);
 305         INIT_VLC_RL(ff_rl_table[4], 962);
 306         INIT_VLC_RL(ff_rl_table[5], 554);
 307
 308         mv = &ff_mv_tables[0];
 309         INIT_VLC_STATIC(&mv->vlc, MV_VLC_BITS, mv->n + 1,
 310                     mv->table_mv_bits, 1, 1,
 311                     mv->table_mv_code, 2, 2, 3714);
 312         mv = &ff_mv_tables[1];
 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, 2694);
 316
 317         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[0], DC_VLC_BITS, 120,
 318                  &ff_table0_dc_lum[0][1], 8, 4,
 319                  &ff_table0_dc_lum[0][0], 8, 4, 1158);
 320         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[0], DC_VLC_BITS, 120,
 321                  &ff_table0_dc_chroma[0][1], 8, 4,
 322                  &ff_table0_dc_chroma[0][0], 8, 4, 1118);
 323         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[1], DC_VLC_BITS, 120,
 324                  &ff_table1_dc_lum[0][1], 8, 4,
 325                  &ff_table1_dc_lum[0][0], 8, 4, 1476);
 326         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[1], DC_VLC_BITS, 120,
 327                  &ff_table1_dc_chroma[0][1], 8, 4,
 328                  &ff_table1_dc_chroma[0][0], 8, 4, 1216);
 329
 330         INIT_VLC_STATIC(&v2_dc_lum_vlc, DC_VLC_BITS, 512,
 331                  &ff_v2_dc_lum_table[0][1], 8, 4,
 332                  &ff_v2_dc_lum_table[0][0], 8, 4, 1472);
 333         INIT_VLC_STATIC(&v2_dc_chroma_vlc, DC_VLC_BITS, 512,
 334                  &ff_v2_dc_chroma_table[0][1], 8, 4,
 335                  &ff_v2_dc_chroma_table[0][0], 8, 4, 1506);
 336
 337         INIT_VLC_STATIC(&v2_intra_cbpc_vlc, V2_INTRA_CBPC_VLC_BITS, 4,
 338                  &ff_v2_intra_cbpc[0][1], 2, 1,
 339                  &ff_v2_intra_cbpc[0][0], 2, 1, 8);
 340         INIT_VLC_STATIC(&v2_mb_type_vlc, V2_MB_TYPE_VLC_BITS, 8,
 341                  &ff_v2_mb_type[0][1], 2, 1,
 342                  &ff_v2_mb_type[0][0], 2, 1, 128);
 343         INIT_VLC_STATIC(&v2_mv_vlc, V2_MV_VLC_BITS, 33,
 344                  &ff_mvtab[0][1], 2, 1,
 345                  &ff_mvtab[0][0], 2, 1, 538);
 346
 347         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[0], MB_NON_INTRA_VLC_BITS, 128,
 348                      &ff_wmv2_inter_table[0][0][1], 8, 4,
 349                      &ff_wmv2_inter_table[0][0][0], 8, 4, 1636);
 350         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[1], MB_NON_INTRA_VLC_BITS, 128,
 351                      &ff_wmv2_inter_table[1][0][1], 8, 4,
 352                      &ff_wmv2_inter_table[1][0][0], 8, 4, 2648);
 353         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[2], MB_NON_INTRA_VLC_BITS, 128,
 354                      &ff_wmv2_inter_table[2][0][1], 8, 4,
 355                      &ff_wmv2_inter_table[2][0][0], 8, 4, 1532);
 356         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[3], MB_NON_INTRA_VLC_BITS, 128,
 357                      &ff_wmv2_inter_table[3][0][1], 8, 4,
 358                      &ff_wmv2_inter_table[3][0][0], 8, 4, 2488);
 359
 360         INIT_VLC_STATIC(&ff_msmp4_mb_i_vlc, MB_INTRA_VLC_BITS, 64,
 361                  &ff_msmp4_mb_i_table[0][1], 4, 2,
 362                  &ff_msmp4_mb_i_table[0][0], 4, 2, 536);
 363
 364         INIT_VLC_STATIC(&ff_inter_intra_vlc, INTER_INTRA_VLC_BITS, 4,
 365                  &ff_table_inter_intra[0][1], 2, 1,
 366                  &ff_table_inter_intra[0][0], 2, 1, 8);
 367     }
 368
 369     switch(s->msmpeg4_version){
 370     case 1:
 371     case 2:
 372         s->decode_mb= msmpeg4v12_decode_mb;
 373         break;
 374     case 3:
 375     case 4:
 376         s->decode_mb= msmpeg4v34_decode_mb;
 377         break;
 378     case 5:
 379         if (CONFIG_WMV2_DECODER)
 380             s->decode_mb= ff_wmv2_decode_mb;
 381     case 6:
 382         //FIXME + TODO VC1 decode mb
 383         break;
 384     }
 385
 386     s->slice_height= s->mb_height; //to avoid 1/0 if the first frame is not a keyframe
 387
 388     return 0;
 389 }
 390
 391 int ff_msmpeg4_decode_picture_header(MpegEncContext * s)
 392 {
 393     int code;
 394
 395     if(s->msmpeg4_version==1){
 396         int start_code = get_bits_long(&s->gb, 32);
 397         if(start_code!=0x00000100){
 398             av_log(s->avctx, AV_LOG_ERROR, "invalid startcode\n");
 399             return -1;
 400         }
 401
 402         skip_bits(&s->gb, 5); // frame number */
 403     }
 404
 405     s->pict_type = get_bits(&s->gb, 2) + 1;
 406     if (s->pict_type != AV_PICTURE_TYPE_I &&
 407         s->pict_type != AV_PICTURE_TYPE_P){
 408         av_log(s->avctx, AV_LOG_ERROR, "invalid picture type\n");
 409         return -1;
 410     }
 411 #if 0
 412 {
 413     static int had_i=0;
 414     if(s->pict_type == AV_PICTURE_TYPE_I) had_i=1;
 415     if(!had_i) return -1;
 416 }
 417 #endif
 418     s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
 419     if(s->qscale==0){
 420         av_log(s->avctx, AV_LOG_ERROR, "invalid qscale\n");
 421         return -1;
 422     }
 423
 424     if (s->pict_type == AV_PICTURE_TYPE_I) {
 425         code = get_bits(&s->gb, 5);
 426         if(s->msmpeg4_version==1){
 427             if(code==0 || code>s->mb_height){
 428                 av_log(s->avctx, AV_LOG_ERROR, "invalid slice height %d\n", code);
 429                 return -1;
 430             }
 431
 432             s->slice_height = code;
 433         }else{
 434             /* 0x17: one slice, 0x18: two slices, ... */
 435             if (code < 0x17){
 436                 av_log(s->avctx, AV_LOG_ERROR, "error, slice code was %X\n", code);
 437                 return -1;
 438             }
 439
 440             s->slice_height = s->mb_height / (code - 0x16);
 441         }
 442
 443         switch(s->msmpeg4_version){
 444         case 1:
 445         case 2:
 446             s->rl_chroma_table_index = 2;
 447             s->rl_table_index = 2;
 448
 449             s->dc_table_index = 0; //not used
 450             break;
 451         case 3:
 452             s->rl_chroma_table_index = decode012(&s->gb);
 453             s->rl_table_index = decode012(&s->gb);
 454
 455             s->dc_table_index = get_bits1(&s->gb);
 456             break;
 457         case 4:
 458             ff_msmpeg4_decode_ext_header(s, (2+5+5+17+7)/8);
 459
 460             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
 461             else                           s->per_mb_rl_table= 0;
 462
 463             if(!s->per_mb_rl_table){
 464                 s->rl_chroma_table_index = decode012(&s->gb);
 465                 s->rl_table_index = decode012(&s->gb);
 466             }
 467
 468             s->dc_table_index = get_bits1(&s->gb);
 469             s->inter_intra_pred= 0;
 470             break;
 471         }
 472         s->no_rounding = 1;
 473         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
 474             av_log(s->avctx, AV_LOG_DEBUG, "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d slice:%d   \n",
 475                 s->qscale,
 476                 s->rl_chroma_table_index,
 477                 s->rl_table_index,
 478                 s->dc_table_index,
 479                 s->per_mb_rl_table,
 480                 s->slice_height);
 481     } else {
 482         switch(s->msmpeg4_version){
 483         case 1:
 484         case 2:
 485             if(s->msmpeg4_version==1)
 486                 s->use_skip_mb_code = 1;
 487             else
 488                 s->use_skip_mb_code = get_bits1(&s->gb);
 489             s->rl_table_index = 2;
 490             s->rl_chroma_table_index = s->rl_table_index;
 491             s->dc_table_index = 0; //not used
 492             s->mv_table_index = 0;
 493             break;
 494         case 3:
 495             s->use_skip_mb_code = get_bits1(&s->gb);
 496             s->rl_table_index = decode012(&s->gb);
 497             s->rl_chroma_table_index = s->rl_table_index;
 498
 499             s->dc_table_index = get_bits1(&s->gb);
 500
 501             s->mv_table_index = get_bits1(&s->gb);
 502             break;
 503         case 4:
 504             s->use_skip_mb_code = get_bits1(&s->gb);
 505
 506             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
 507             else                           s->per_mb_rl_table= 0;
 508
 509             if(!s->per_mb_rl_table){
 510                 s->rl_table_index = decode012(&s->gb);
 511                 s->rl_chroma_table_index = s->rl_table_index;
 512             }
 513
 514             s->dc_table_index = get_bits1(&s->gb);
 515
 516             s->mv_table_index = get_bits1(&s->gb);
 517             s->inter_intra_pred= (s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE);
 518             break;
 519         }
 520
 521         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
 522             av_log(s->avctx, AV_LOG_DEBUG, "skip:%d rl:%d rlc:%d dc:%d mv:%d mbrl:%d qp:%d   \n",
 523                 s->use_skip_mb_code,
 524                 s->rl_table_index,
 525                 s->rl_chroma_table_index,
 526                 s->dc_table_index,
 527                 s->mv_table_index,
 528                 s->per_mb_rl_table,
 529                 s->qscale);
 530
 531         if(s->flipflop_rounding){
 532             s->no_rounding ^= 1;
 533         }else{
 534             s->no_rounding = 0;
 535         }
 536     }
 537     ff_dlog(s->avctx, "%d %d %d %d %d\n", s->pict_type, s->bit_rate,
 538             s->inter_intra_pred, s->width, s->height);
 539
 540     s->esc3_level_length= 0;
 541     s->esc3_run_length= 0;
 542
 543     return 0;
 544 }
 545
 546 int ff_msmpeg4_decode_ext_header(MpegEncContext * s, int buf_size)
 547 {
 548     int left= buf_size*8 - get_bits_count(&s->gb);
 549     int length= s->msmpeg4_version>=3 ? 17 : 16;
 550     /* the alt_bitstream reader could read over the end so we need to check it */
 551     if(left>=length && left<length+8)
 552     {
 553         skip_bits(&s->gb, 5); /* fps */
 554         s->bit_rate= get_bits(&s->gb, 11)*1024;
 555         if(s->msmpeg4_version>=3)
 556             s->flipflop_rounding= get_bits1(&s->gb);
 557         else
 558             s->flipflop_rounding= 0;
 559     }
 560     else if(left<length+8)
 561     {
 562         s->flipflop_rounding= 0;
 563         if(s->msmpeg4_version != 2)
 564             av_log(s->avctx, AV_LOG_ERROR, "ext header missing, %d left\n", left);
 565     }
 566     else
 567     {
 568         av_log(s->avctx, AV_LOG_ERROR, "I-frame too long, ignoring ext header\n");
 569     }
 570
 571     return 0;
 572 }
 573
 574 static int msmpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
 575 {
 576     int level, pred;
 577
 578     if(s->msmpeg4_version<=2){
 579         if (n < 4) {
 580             level = get_vlc2(&s->gb, v2_dc_lum_vlc.table, DC_VLC_BITS, 3);
 581         } else {
 582             level = get_vlc2(&s->gb, v2_dc_chroma_vlc.table, DC_VLC_BITS, 3);
 583         }
 584         if (level < 0)
 585             return -1;
 586         level-=256;
 587     }else{  //FIXME optimize use unified tables & index
 588         if (n < 4) {
 589             level = get_vlc2(&s->gb, ff_msmp4_dc_luma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
 590         } else {
 591             level = get_vlc2(&s->gb, ff_msmp4_dc_chroma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
 592         }
 593         if (level < 0){
 594             av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
 595             return -1;
 596         }
 597
 598         if (level == DC_MAX) {
 599             level = get_bits(&s->gb, 8);
 600             if (get_bits1(&s->gb))
 601                 level = -level;
 602         } else if (level != 0) {
 603             if (get_bits1(&s->gb))
 604                 level = -level;
 605         }
 606     }
 607
 608     if(s->msmpeg4_version==1){
 609         int32_t *dc_val;
 610         pred = msmpeg4v1_pred_dc(s, n, &dc_val);
 611         level += pred;
 612
 613         /* update predictor */
 614         *dc_val= level;
 615     }else{
 616         int16_t *dc_val;
 617         pred   = ff_msmpeg4_pred_dc(s, n, &dc_val, dir_ptr);
 618         level += pred;
 619
 620         /* update predictor */
 621         if (n < 4) {
 622             *dc_val = level * s->y_dc_scale;
 623         } else {
 624             *dc_val = level * s->c_dc_scale;
 625         }
 626     }
 627
 628     return level;
 629 }
 630
 631 //#define ERROR_DETAILS
 632 int ff_msmpeg4_decode_block(MpegEncContext * s, int16_t * block,
 633                               int n, int coded, const uint8_t *scan_table)
 634 {
 635     int level, i, last, run, run_diff;
 636     int av_uninit(dc_pred_dir);
 637     RLTable *rl;
 638     RL_VLC_ELEM *rl_vlc;
 639     int qmul, qadd;
 640
 641     if (s->mb_intra) {
 642         qmul=1;
 643         qadd=0;
 644
 645         /* DC coef */
 646         level = msmpeg4_decode_dc(s, n, &dc_pred_dir);
 647
 648         if (level < 0){
 649             av_log(s->avctx, AV_LOG_ERROR, "dc overflow- block: %d qscale: %d//\n", n, s->qscale);
 650             if(s->inter_intra_pred) level=0;
 651             else                    return -1;
 652         }
 653         if (n < 4) {
 654             rl = &ff_rl_table[s->rl_table_index];
 655             if(level > 256*s->y_dc_scale){
 656                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ L qscale: %d//\n", s->qscale);
 657                 if(!s->inter_intra_pred) return -1;
 658             }
 659         } else {
 660             rl = &ff_rl_table[3 + s->rl_chroma_table_index];
 661             if(level > 256*s->c_dc_scale){
 662                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ C qscale: %d//\n", s->qscale);
 663                 if(!s->inter_intra_pred) return -1;
 664             }
 665         }
 666         block[0] = level;
 667
 668         run_diff = s->msmpeg4_version >= 4;
 669         i = 0;
 670         if (!coded) {
 671             goto not_coded;
 672         }
 673         if (s->ac_pred) {
 674             if (dc_pred_dir == 0)
 675                 scan_table = s->intra_v_scantable.permutated; /* left */
 676             else
 677                 scan_table = s->intra_h_scantable.permutated; /* top */
 678         } else {
 679             scan_table = s->intra_scantable.permutated;
 680         }
 681         rl_vlc= rl->rl_vlc[0];
 682     } else {
 683         qmul = s->qscale << 1;
 684         qadd = (s->qscale - 1) | 1;
 685         i = -1;
 686         rl = &ff_rl_table[3 + s->rl_table_index];
 687
 688         if(s->msmpeg4_version==2)
 689             run_diff = 0;
 690         else
 691             run_diff = 1;
 692
 693         if (!coded) {
 694             s->block_last_index[n] = i;
 695             return 0;
 696         }
 697         if(!scan_table)
 698             scan_table = s->inter_scantable.permutated;
 699         rl_vlc= rl->rl_vlc[s->qscale];
 700     }
 701   {
 702     OPEN_READER(re, &s->gb);
 703     for(;;) {
 704         UPDATE_CACHE(re, &s->gb);
 705         GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
 706         if (level==0) {
 707             int cache;
 708             cache= GET_CACHE(re, &s->gb);
 709             /* escape */
 710             if (s->msmpeg4_version==1 || (cache&0x80000000)==0) {
 711                 if (s->msmpeg4_version==1 || (cache&0x40000000)==0) {
 712                     /* third escape */
 713                     if(s->msmpeg4_version!=1) LAST_SKIP_BITS(re, &s->gb, 2);
 714                     UPDATE_CACHE(re, &s->gb);
 715                     if(s->msmpeg4_version<=3){
 716                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
 717                         run=   SHOW_UBITS(re, &s->gb, 6); SKIP_CACHE(re, &s->gb, 6);
 718                         level= SHOW_SBITS(re, &s->gb, 8);
 719                         SKIP_COUNTER(re, &s->gb, 1+6+8);
 720                     }else{
 721                         int sign;
 722                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
 723                         if(!s->esc3_level_length){
 724                             int ll;
 725                             ff_dlog(s->avctx, "ESC-3 %X at %d %d\n",
 726                                     show_bits(&s->gb, 24), s->mb_x, s->mb_y);
 727                             if(s->qscale<8){
 728                                 ll= SHOW_UBITS(re, &s->gb, 3); SKIP_BITS(re, &s->gb, 3);
 729                                 if(ll==0){
 730                                     ll= 8+SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
 731                                 }
 732                             }else{
 733                                 ll=2;
 734                                 while(ll<8 && SHOW_UBITS(re, &s->gb, 1)==0){
 735                                     ll++;
 736                                     SKIP_BITS(re, &s->gb, 1);
 737                                 }
 738                                 if(ll<8) SKIP_BITS(re, &s->gb, 1);
 739                             }
 740
 741                             s->esc3_level_length= ll;
 742                             s->esc3_run_length= SHOW_UBITS(re, &s->gb, 2) + 3; SKIP_BITS(re, &s->gb, 2);
 743                             UPDATE_CACHE(re, &s->gb);
 744                         }
 745                         run=   SHOW_UBITS(re, &s->gb, s->esc3_run_length);
 746                         SKIP_BITS(re, &s->gb, s->esc3_run_length);
 747
 748                         sign=  SHOW_UBITS(re, &s->gb, 1);
 749                         SKIP_BITS(re, &s->gb, 1);
 750
 751                         level= SHOW_UBITS(re, &s->gb, s->esc3_level_length);
 752                         SKIP_BITS(re, &s->gb, s->esc3_level_length);
 753                         if(sign) level= -level;
 754                     }
 755
 756 #if 0 // waste of time / this will detect very few errors
 757                     {
 758                         const int abs_level= FFABS(level);
 759                         const int run1= run - rl->max_run[last][abs_level] - run_diff;
 760                         if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
 761                             if(abs_level <= rl->max_level[last][run]){
 762                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
 763                                 return DECODING_AC_LOST;
 764                             }
 765                             if(abs_level <= rl->max_level[last][run]*2){
 766                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
 767                                 return DECODING_AC_LOST;
 768                             }
 769                             if(run1>=0 && abs_level <= rl->max_level[last][run1]){
 770                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
 771                                 return DECODING_AC_LOST;
 772                             }
 773                         }
 774                     }
 775 #endif
 776                     //level = level * qmul + (level>0) * qadd - (level<=0) * qadd ;
 777                     if (level>0) level= level * qmul + qadd;
 778                     else         level= level * qmul - qadd;
 779 #if 0 // waste of time too :(
 780                     if(level>2048 || level<-2048){
 781                         av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc\n");
 782                         return DECODING_AC_LOST;
 783                     }
 784 #endif
 785                     i+= run + 1;
 786                     if(last) i+=192;
 787 #ifdef ERROR_DETAILS
 788                 if(run==66)
 789                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC3 level=%d\n", level);
 790                 else if((i>62 && i<192) || i>192+63)
 791                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC3 i=%d run=%d level=%d\n", i, run, level);
 792 #endif
 793                 } else {
 794                     /* second escape */
 795                     SKIP_BITS(re, &s->gb, 2);
 796                     GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
 797                     i+= run + rl->max_run[run>>7][level/qmul] + run_diff; //FIXME opt indexing
 798                     level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 799                     LAST_SKIP_BITS(re, &s->gb, 1);
 800 #ifdef ERROR_DETAILS
 801                 if(run==66)
 802                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC2 level=%d\n", level);
 803                 else if((i>62 && i<192) || i>192+63)
 804                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC2 i=%d run=%d level=%d\n", i, run, level);
 805 #endif
 806                 }
 807             } else {
 808                 /* first escape */
 809                 SKIP_BITS(re, &s->gb, 1);
 810                 GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
 811                 i+= run;
 812                 level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
 813                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 814                 LAST_SKIP_BITS(re, &s->gb, 1);
 815 #ifdef ERROR_DETAILS
 816                 if(run==66)
 817                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC1 level=%d\n", level);
 818                 else if((i>62 && i<192) || i>192+63)
 819                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC1 i=%d run=%d level=%d\n", i, run, level);
 820 #endif
 821             }
 822         } else {
 823             i+= run;
 824             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 825             LAST_SKIP_BITS(re, &s->gb, 1);
 826 #ifdef ERROR_DETAILS
 827                 if(run==66)
 828                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code level=%d\n", level);
 829                 else if((i>62 && i<192) || i>192+63)
 830                     av_log(s->avctx, AV_LOG_ERROR, "run overflow i=%d run=%d level=%d\n", i, run, level);
 831 #endif
 832         }
 833         if (i > 62){
 834             i-= 192;
 835             if(i&(~63)){
 836                 const int left= get_bits_left(&s->gb);
 837                 if (((i + 192 == 64 && level / qmul == -1) ||
 838                      !(s->avctx->err_recognition & AV_EF_BITSTREAM)) &&
 839                     left >= 0) {
 840                     av_log(s->avctx, AV_LOG_ERROR, "ignoring overflow at %d %d\n", s->mb_x, s->mb_y);
 841                     break;
 842                 }else{
 843                     av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 844                     return -1;
 845                 }
 846             }
 847
 848             block[scan_table[i]] = level;
 849             break;
 850         }
 851
 852         block[scan_table[i]] = level;
 853     }
 854     CLOSE_READER(re, &s->gb);
 855   }
 856  not_coded:
 857     if (s->mb_intra) {
 858         ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
 859         if (s->ac_pred) {
 860             i = 63; /* XXX: not optimal */
 861         }
 862     }
 863     if(s->msmpeg4_version>=4 && i>0) i=63; //FIXME/XXX optimize
 864     s->block_last_index[n] = i;
 865
 866     return 0;
 867 }
 868
 869 int ff_msmpeg4_decode_motion(MpegEncContext * s,
 870                                  int *mx_ptr, int *my_ptr)
 871 {
 872     MVTable *mv;
 873     int code, mx, my;
 874
 875     mv = &ff_mv_tables[s->mv_table_index];
 876
 877     code = get_vlc2(&s->gb, mv->vlc.table, MV_VLC_BITS, 2);
 878     if (code < 0){
 879         av_log(s->avctx, AV_LOG_ERROR, "illegal MV code at %d %d\n", s->mb_x, s->mb_y);
 880         return -1;
 881     }
 882     if (code == mv->n) {
 883         mx = get_bits(&s->gb, 6);
 884         my = get_bits(&s->gb, 6);
 885     } else {
 886         mx = mv->table_mvx[code];
 887         my = mv->table_mvy[code];
 888     }
 889
 890     mx += *mx_ptr - 32;
 891     my += *my_ptr - 32;
 892     /* WARNING : they do not do exactly modulo encoding */
 893     if (mx <= -64)
 894         mx += 64;
 895     else if (mx >= 64)
 896         mx -= 64;
 897
 898     if (my <= -64)
 899         my += 64;
 900     else if (my >= 64)
 901         my -= 64;
 902     *mx_ptr = mx;
 903     *my_ptr = my;
 904     return 0;
 905 }
 906
 907 AVCodec ff_msmpeg4v1_decoder = {
 908     .name           = "msmpeg4v1",
 909     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 1"),
 910     .type           = AVMEDIA_TYPE_VIDEO,
 911     .id             = AV_CODEC_ID_MSMPEG4V1,
 912     .priv_data_size = sizeof(MpegEncContext),
 913     .init           = ff_msmpeg4_decode_init,
 914     .close          = ff_h263_decode_end,
 915     .decode         = ff_h263_decode_frame,
 916     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 917     .pix_fmts       = (const enum AVPixelFormat[]) {
 918         AV_PIX_FMT_YUV420P,
 919         AV_PIX_FMT_NONE
 920     },
 921 };
 922
 923 AVCodec ff_msmpeg4v2_decoder = {
 924     .name           = "msmpeg4v2",
 925     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 2"),
 926     .type           = AVMEDIA_TYPE_VIDEO,
 927     .id             = AV_CODEC_ID_MSMPEG4V2,
 928     .priv_data_size = sizeof(MpegEncContext),
 929     .init           = ff_msmpeg4_decode_init,
 930     .close          = ff_h263_decode_end,
 931     .decode         = ff_h263_decode_frame,
 932     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 933     .pix_fmts       = (const enum AVPixelFormat[]) {
 934         AV_PIX_FMT_YUV420P,
 935         AV_PIX_FMT_NONE
 936     },
 937 };
 938
 939 AVCodec ff_msmpeg4v3_decoder = {
 940     .name           = "msmpeg4",
 941     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 3"),
 942     .type           = AVMEDIA_TYPE_VIDEO,
 943     .id             = AV_CODEC_ID_MSMPEG4V3,
 944     .priv_data_size = sizeof(MpegEncContext),
 945     .init           = ff_msmpeg4_decode_init,
 946     .close          = ff_h263_decode_end,
 947     .decode         = ff_h263_decode_frame,
 948     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 949     .pix_fmts       = (const enum AVPixelFormat[]) {
 950         AV_PIX_FMT_YUV420P,
 951         AV_PIX_FMT_NONE
 952     },
 953 };
 954
 955 AVCodec ff_wmv1_decoder = {
 956     .name           = "wmv1",
 957     .long_name      = NULL_IF_CONFIG_SMALL("Windows Media Video 7"),
 958     .type           = AVMEDIA_TYPE_VIDEO,
 959     .id             = AV_CODEC_ID_WMV1,
 960     .priv_data_size = sizeof(MpegEncContext),
 961     .init           = ff_msmpeg4_decode_init,
 962     .close          = ff_h263_decode_end,
 963     .decode         = ff_h263_decode_frame,
 964     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,
 965     .pix_fmts       = (const enum AVPixelFormat[]) {
 966         AV_PIX_FMT_YUV420P,
 967         AV_PIX_FMT_NONE
 968     },
 969 };