vp8/decoder/decodemv.c

   1 /*
   2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   3  *
   4  *  Use of this source code is governed by a BSD-style license
   5  *  that can be found in the LICENSE file in the root of the source
   6  *  tree. An additional intellectual property rights grant can be found
   7  *  in the file PATENTS.  All contributing project authors may
   8  *  be found in the AUTHORS file in the root of the source tree.
   9  */
  10
  11
  12 #include "treereader.h"
  13 #include "vp8/common/entropymv.h"
  14 #include "vp8/common/entropymode.h"
  15 #include "onyxd_int.h"
  16 #include "vp8/common/findnearmv.h"
  17
  18 #if CONFIG_DEBUG
  19 #include <assert.h>
  20 #endif
  21 static int vp8_read_bmode(vp8_reader *bc, const vp8_prob *p)
  22 {
  23     const int i = vp8_treed_read(bc, vp8_bmode_tree, p);
  24
  25     return i;
  26 }
  27
  28
  29 static int vp8_read_ymode(vp8_reader *bc, const vp8_prob *p)
  30 {
  31     const int i = vp8_treed_read(bc, vp8_ymode_tree, p);
  32
  33     return i;
  34 }
  35
  36 static int vp8_kfread_ymode(vp8_reader *bc, const vp8_prob *p)
  37 {
  38     const int i = vp8_treed_read(bc, vp8_kf_ymode_tree, p);
  39
  40     return i;
  41 }
  42
  43
  44
  45 static int vp8_read_uv_mode(vp8_reader *bc, const vp8_prob *p)
  46 {
  47     const int i = vp8_treed_read(bc, vp8_uv_mode_tree, p);
  48
  49     return i;
  50 }
  51
  52 static void vp8_read_mb_features(vp8_reader *r, MB_MODE_INFO *mi, MACROBLOCKD *x)
  53 {
  54     /* Is segmentation enabled */
  55     if (x->segmentation_enabled && x->update_mb_segmentation_map)
  56     {
  57         /* If so then read the segment id. */
  58         if (vp8_read(r, x->mb_segment_tree_probs[0]))
  59             mi->segment_id = (unsigned char)(2 + vp8_read(r, x->mb_segment_tree_probs[2]));
  60         else
  61             mi->segment_id = (unsigned char)(vp8_read(r, x->mb_segment_tree_probs[1]));
  62     }
  63 }
  64
  65 static void vp8_kfread_modes(VP8D_COMP *pbi, MODE_INFO *m, int mb_row, int mb_col)
  66 {
  67     vp8_reader *const bc = & pbi->bc;
  68     const int mis = pbi->common.mode_info_stride;
  69
  70         {
  71             MB_PREDICTION_MODE y_mode;
  72
  73             /* Read the Macroblock segmentation map if it is being updated explicitly this frame (reset to 0 above by default)
  74              * By default on a key frame reset all MBs to segment 0
  75              */
  76             m->mbmi.segment_id = 0;
  77
  78             if (pbi->mb.update_mb_segmentation_map)
  79                 vp8_read_mb_features(bc, &m->mbmi, &pbi->mb);
  80
  81             /* Read the macroblock coeff skip flag if this feature is in use, else default to 0 */
  82             if (pbi->common.mb_no_coeff_skip)
  83                 m->mbmi.mb_skip_coeff = vp8_read(bc, pbi->prob_skip_false);
  84             else
  85                 m->mbmi.mb_skip_coeff = 0;
  86
  87             y_mode = (MB_PREDICTION_MODE) vp8_kfread_ymode(bc, pbi->common.kf_ymode_prob);
  88
  89             m->mbmi.ref_frame = INTRA_FRAME;
  90
  91             if ((m->mbmi.mode = y_mode) == B_PRED)
  92             {
  93                 int i = 0;
  94
  95                 do
  96                 {
  97                     const B_PREDICTION_MODE A = above_block_mode(m, i, mis);
  98                     const B_PREDICTION_MODE L = left_block_mode(m, i);
  99
 100                     m->bmi[i].as_mode = (B_PREDICTION_MODE) vp8_read_bmode(bc, pbi->common.kf_bmode_prob [A] [L]);
 101                 }
 102                 while (++i < 16);
 103             }
 104             else
 105             {
 106                 int BMode;
 107                 int i = 0;
 108
 109                 switch (y_mode)
 110                 {
 111                 case DC_PRED:
 112                     BMode = B_DC_PRED;
 113                     break;
 114                 case V_PRED:
 115                     BMode = B_VE_PRED;
 116                     break;
 117                 case H_PRED:
 118                     BMode = B_HE_PRED;
 119                     break;
 120                 case TM_PRED:
 121                     BMode = B_TM_PRED;
 122                     break;
 123                 default:
 124                     BMode = B_DC_PRED;
 125                     break;
 126                 }
 127
 128                 do
 129                 {
 130                     m->bmi[i].as_mode = (B_PREDICTION_MODE)BMode;
 131                 }
 132                 while (++i < 16);
 133             }
 134
 135             m->mbmi.uv_mode = (MB_PREDICTION_MODE)vp8_read_uv_mode(bc, pbi->common.kf_uv_mode_prob);
 136         }
 137 }
 138
 139 static int read_mvcomponent(vp8_reader *r, const MV_CONTEXT *mvc)
 140 {
 141     const vp8_prob *const p = (const vp8_prob *) mvc;
 142     int x = 0;
 143
 144     if (vp8_read(r, p [mvpis_short]))  /* Large */
 145     {
 146         int i = 0;
 147
 148         do
 149         {
 150             x += vp8_read(r, p [MVPbits + i]) << i;
 151         }
 152         while (++i < 3);
 153
 154         i = mvlong_width - 1;  /* Skip bit 3, which is sometimes implicit */
 155
 156         do
 157         {
 158             x += vp8_read(r, p [MVPbits + i]) << i;
 159         }
 160         while (--i > 3);
 161
 162         if (!(x & 0xFFF0)  ||  vp8_read(r, p [MVPbits + 3]))
 163             x += 8;
 164     }
 165     else   /* small */
 166         x = vp8_treed_read(r, vp8_small_mvtree, p + MVPshort);
 167
 168     if (x  &&  vp8_read(r, p [MVPsign]))
 169         x = -x;
 170
 171     return x;
 172 }
 173
 174 static void read_mv(vp8_reader *r, MV *mv, const MV_CONTEXT *mvc)
 175 {
 176     mv->row = (short)(read_mvcomponent(r,   mvc) << 1);
 177     mv->col = (short)(read_mvcomponent(r, ++mvc) << 1);
 178 }
 179
 180
 181 static void read_mvcontexts(vp8_reader *bc, MV_CONTEXT *mvc)
 182 {
 183     int i = 0;
 184
 185     do
 186     {
 187         const vp8_prob *up = vp8_mv_update_probs[i].prob;
 188         vp8_prob *p = (vp8_prob *)(mvc + i);
 189         vp8_prob *const pstop = p + MVPcount;
 190
 191         do
 192         {
 193             if (vp8_read(bc, *up++))
 194             {
 195                 const vp8_prob x = (vp8_prob)vp8_read_literal(bc, 7);
 196
 197                 *p = x ? x << 1 : 1;
 198             }
 199         }
 200         while (++p < pstop);
 201     }
 202     while (++i < 2);
 203 }
 204
 205
 206 static MB_PREDICTION_MODE read_mv_ref(vp8_reader *bc, const vp8_prob *p)
 207 {
 208     const int i = vp8_treed_read(bc, vp8_mv_ref_tree, p);
 209
 210     return (MB_PREDICTION_MODE)i;
 211 }
 212
 213 static MB_PREDICTION_MODE sub_mv_ref(vp8_reader *bc, const vp8_prob *p)
 214 {
 215     const int i = vp8_treed_read(bc, vp8_sub_mv_ref_tree, p);
 216
 217     return (MB_PREDICTION_MODE)i;
 218 }
 219
 220 #ifdef VPX_MODE_COUNT
 221 unsigned int vp8_mv_cont_count[5][4] =
 222 {
 223     { 0, 0, 0, 0 },
 224     { 0, 0, 0, 0 },
 225     { 0, 0, 0, 0 },
 226     { 0, 0, 0, 0 },
 227     { 0, 0, 0, 0 }
 228 };
 229 #endif
 230
 231 static const unsigned char mbsplit_fill_count[4] = {8, 8, 4, 1};
 232 static const unsigned char mbsplit_fill_offset[4][16] = {
 233     { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13, 14, 15},
 234     { 0,  1,  4,  5,  8,  9, 12, 13,  2,  3,   6,  7, 10, 11, 14, 15},
 235     { 0,  1,  4,  5,  2,  3,  6,  7,  8,  9,  12, 13, 10, 11, 14, 15},
 236     { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13, 14, 15}
 237 };
 238
 239
 240
 241
 242 static void mb_mode_mv_init(VP8D_COMP *pbi)
 243 {
 244     vp8_reader *const bc = & pbi->bc;
 245     MV_CONTEXT *const mvc = pbi->common.fc.mvc;
 246
 247 #if CONFIG_ERROR_CONCEALMENT
 248     /* Default is that no macroblock is corrupt, therefore we initialize
 249      * mvs_corrupt_from_mb to something very big, which we can be sure is
 250      * outside the frame. */
 251     pbi->mvs_corrupt_from_mb = UINT_MAX;
 252 #endif
 253     pbi->prob_skip_false = 0;
 254     if (pbi->common.mb_no_coeff_skip)
 255         pbi->prob_skip_false = (vp8_prob)vp8_read_literal(bc, 8);
 256
 257     if(pbi->common.frame_type != KEY_FRAME)
 258     {
 259         pbi->prob_intra = (vp8_prob)vp8_read_literal(bc, 8);
 260         pbi->prob_last  = (vp8_prob)vp8_read_literal(bc, 8);
 261         pbi->prob_gf    = (vp8_prob)vp8_read_literal(bc, 8);
 262
 263         if (vp8_read_bit(bc))
 264         {
 265             int i = 0;
 266
 267             do
 268             {
 269                 pbi->common.fc.ymode_prob[i] = (vp8_prob) vp8_read_literal(bc, 8);
 270             }
 271             while (++i < 4);
 272         }
 273
 274         if (vp8_read_bit(bc))
 275         {
 276             int i = 0;
 277
 278             do
 279             {
 280                 pbi->common.fc.uv_mode_prob[i] = (vp8_prob) vp8_read_literal(bc, 8);
 281             }
 282             while (++i < 3);
 283         }
 284
 285         read_mvcontexts(bc, mvc);
 286     }
 287 }
 288
 289
 290 static void read_mb_modes_mv(VP8D_COMP *pbi, MODE_INFO *mi, MB_MODE_INFO *mbmi,
 291                             int mb_row, int mb_col)
 292 {
 293     vp8_reader *const bc = & pbi->bc;
 294     MV_CONTEXT *const mvc = pbi->common.fc.mvc;
 295     const int mis = pbi->common.mode_info_stride;
 296
 297     int_mv *const mv = & mbmi->mv;
 298     int mb_to_left_edge;
 299     int mb_to_right_edge;
 300     int mb_to_top_edge;
 301     int mb_to_bottom_edge;
 302
 303     mb_to_top_edge = pbi->mb.mb_to_top_edge;
 304     mb_to_bottom_edge = pbi->mb.mb_to_bottom_edge;
 305     mb_to_top_edge -= LEFT_TOP_MARGIN;
 306     mb_to_bottom_edge += RIGHT_BOTTOM_MARGIN;
 307
 308     mbmi->need_to_clamp_mvs = 0;
 309     /* Distance of Mb to the various image edges.
 310      * These specified to 8th pel as they are always compared to MV values that are in 1/8th pel units
 311      */
 312     pbi->mb.mb_to_left_edge =
 313     mb_to_left_edge = -((mb_col * 16) << 3);
 314     mb_to_left_edge -= LEFT_TOP_MARGIN;
 315
 316     pbi->mb.mb_to_right_edge =
 317     mb_to_right_edge = ((pbi->common.mb_cols - 1 - mb_col) * 16) << 3;
 318     mb_to_right_edge += RIGHT_BOTTOM_MARGIN;
 319
 320     /* If required read in new segmentation data for this MB */
 321     if (pbi->mb.update_mb_segmentation_map)
 322         vp8_read_mb_features(bc, mbmi, &pbi->mb);
 323
 324     /* Read the macroblock coeff skip flag if this feature is in use, else default to 0 */
 325     if (pbi->common.mb_no_coeff_skip)
 326         mbmi->mb_skip_coeff = vp8_read(bc, pbi->prob_skip_false);
 327     else
 328         mbmi->mb_skip_coeff = 0;
 329
 330     if ((mbmi->ref_frame = (MV_REFERENCE_FRAME) vp8_read(bc, pbi->prob_intra)))    /* inter MB */
 331     {
 332         int rct[4];
 333         vp8_prob mv_ref_p [VP8_MVREFS-1];
 334         int_mv nearest, nearby, best_mv;
 335
 336         if (vp8_read(bc, pbi->prob_last))
 337         {
 338             mbmi->ref_frame = (MV_REFERENCE_FRAME)((int)mbmi->ref_frame + (int)(1 + vp8_read(bc, pbi->prob_gf)));
 339         }
 340
 341         vp8_find_near_mvs(&pbi->mb, mi, &nearest, &nearby, &best_mv, rct, mbmi->ref_frame, pbi->common.ref_frame_sign_bias);
 342
 343         vp8_mv_ref_probs(mv_ref_p, rct);
 344
 345         mbmi->uv_mode = DC_PRED;
 346         switch (mbmi->mode = read_mv_ref(bc, mv_ref_p))
 347         {
 348         case SPLITMV:
 349         {
 350             const int s = mbmi->partitioning =
 351                       vp8_treed_read(bc, vp8_mbsplit_tree, vp8_mbsplit_probs);
 352             const int num_p = vp8_mbsplit_count [s];
 353             int j = 0;
 354
 355             do  /* for each subset j */
 356             {
 357                 int_mv leftmv, abovemv;
 358                 B_MODE_INFO bmi;
 359                 int k;  /* first block in subset j */
 360                 int mv_contz;
 361                 k = vp8_mbsplit_offset[s][j];
 362
 363                 leftmv.as_int = left_block_mv(mi, k);
 364                 abovemv.as_int = above_block_mv(mi, k, mis);
 365                 mv_contz = vp8_mv_cont(&(leftmv.as_mv), &(abovemv.as_mv));
 366
 367                 switch (bmi.mode = (B_PREDICTION_MODE) sub_mv_ref(bc, vp8_sub_mv_ref_prob2 [mv_contz])) /*pc->fc.sub_mv_ref_prob))*/
 368                 {
 369                 case NEW4X4:
 370                     read_mv(bc, &bmi.mv.as_mv, (const MV_CONTEXT *) mvc);
 371                     bmi.mv.as_mv.row += best_mv.as_mv.row;
 372                     bmi.mv.as_mv.col += best_mv.as_mv.col;
 373   #ifdef VPX_MODE_COUNT
 374                     vp8_mv_cont_count[mv_contz][3]++;
 375   #endif
 376                     break;
 377                 case LEFT4X4:
 378                     bmi.mv.as_int = leftmv.as_int;
 379   #ifdef VPX_MODE_COUNT
 380                     vp8_mv_cont_count[mv_contz][0]++;
 381   #endif
 382                     break;
 383                 case ABOVE4X4:
 384                     bmi.mv.as_int = abovemv.as_int;
 385   #ifdef VPX_MODE_COUNT
 386                     vp8_mv_cont_count[mv_contz][1]++;
 387   #endif
 388                     break;
 389                 case ZERO4X4:
 390                     bmi.mv.as_int = 0;
 391   #ifdef VPX_MODE_COUNT
 392                     vp8_mv_cont_count[mv_contz][2]++;
 393   #endif
 394                     break;
 395                 default:
 396                     break;
 397                 }
 398
 399                 mbmi->need_to_clamp_mvs = vp8_check_mv_bounds(&bmi.mv,
 400                                                           mb_to_left_edge,
 401                                                           mb_to_right_edge,
 402                                                           mb_to_top_edge,
 403                                                           mb_to_bottom_edge);
 404
 405                 {
 406                     /* Fill (uniform) modes, mvs of jth subset.
 407                      Must do it here because ensuing subsets can
 408                      refer back to us via "left" or "above". */
 409                     const unsigned char *fill_offset;
 410                     unsigned int fill_count = mbsplit_fill_count[s];
 411
 412                     fill_offset = &mbsplit_fill_offset[s][(unsigned char)j * mbsplit_fill_count[s]];
 413
 414                     do {
 415                         mi->bmi[ *fill_offset].mv.as_int = bmi.mv.as_int;
 416                         fill_offset++;
 417                     }while (--fill_count);
 418                 }
 419
 420             }
 421             while (++j < num_p);
 422         }
 423
 424         mv->as_int = mi->bmi[15].mv.as_int;
 425
 426         break;  /* done with SPLITMV */
 427
 428         case NEARMV:
 429             mv->as_int = nearby.as_int;
 430             /* Clip "next_nearest" so that it does not extend to far out of image */
 431             vp8_clamp_mv(mv, mb_to_left_edge, mb_to_right_edge,
 432                          mb_to_top_edge, mb_to_bottom_edge);
 433             goto propagate_mv;
 434
 435         case NEARESTMV:
 436             mv->as_int = nearest.as_int;
 437             /* Clip "next_nearest" so that it does not extend to far out of image */
 438             vp8_clamp_mv(mv, mb_to_left_edge, mb_to_right_edge,
 439                          mb_to_top_edge, mb_to_bottom_edge);
 440             goto propagate_mv;
 441
 442         case ZEROMV:
 443             mv->as_int = 0;
 444             goto propagate_mv;
 445
 446         case NEWMV:
 447             read_mv(bc, &mv->as_mv, (const MV_CONTEXT *) mvc);
 448             mv->as_mv.row += best_mv.as_mv.row;
 449             mv->as_mv.col += best_mv.as_mv.col;
 450
 451             /* Don't need to check this on NEARMV and NEARESTMV modes
 452              * since those modes clamp the MV. The NEWMV mode does not,
 453              * so signal to the prediction stage whether special
 454              * handling may be required.
 455              */
 456             mbmi->need_to_clamp_mvs = vp8_check_mv_bounds(mv,
 457                                                       mb_to_left_edge,
 458                                                       mb_to_right_edge,
 459                                                       mb_to_top_edge,
 460                                                       mb_to_bottom_edge);
 461
 462         propagate_mv:  /* same MV throughout */
 463             {
 464                 mi->bmi[ 0].mv.as_int =
 465                 mi->bmi[ 1].mv.as_int =
 466                 mi->bmi[ 2].mv.as_int =
 467                 mi->bmi[ 3].mv.as_int =
 468                 mi->bmi[ 4].mv.as_int =
 469                 mi->bmi[ 5].mv.as_int =
 470                 mi->bmi[ 6].mv.as_int =
 471                 mi->bmi[ 7].mv.as_int =
 472                 mi->bmi[ 8].mv.as_int =
 473                 mi->bmi[ 9].mv.as_int =
 474                 mi->bmi[10].mv.as_int =
 475                 mi->bmi[11].mv.as_int =
 476                 mi->bmi[12].mv.as_int =
 477                 mi->bmi[13].mv.as_int =
 478                 mi->bmi[14].mv.as_int =
 479                 mi->bmi[15].mv.as_int = mv->as_int;
 480             }
 481             break;
 482         default:;
 483   #if CONFIG_DEBUG
 484             assert(0);
 485   #endif
 486         }
 487     }
 488     else
 489     {
 490         /* required for left and above block mv */
 491         mbmi->mv.as_int = 0;
 492
 493         /* MB is intra coded */
 494         if ((mbmi->mode = (MB_PREDICTION_MODE) vp8_read_ymode(bc, pbi->common.fc.ymode_prob)) == B_PRED)
 495         {
 496             int j = 0;
 497             do
 498             {
 499                 mi->bmi[j].as_mode = (B_PREDICTION_MODE)vp8_read_bmode(bc, pbi->common.fc.bmode_prob);
 500             }
 501             while (++j < 16);
 502         }
 503
 504         mbmi->uv_mode = (MB_PREDICTION_MODE)vp8_read_uv_mode(bc, pbi->common.fc.uv_mode_prob);
 505     }
 506
 507 }
 508
 509 void vp8_decode_mode_mvs(VP8D_COMP *pbi)
 510 {
 511     MODE_INFO *mi = pbi->common.mi;
 512     int mb_row = -1;
 513
 514     mb_mode_mv_init(pbi);
 515
 516     while (++mb_row < pbi->common.mb_rows)
 517     {
 518         int mb_col = -1;
 519         int mb_to_top_edge;
 520         int mb_to_bottom_edge;
 521
 522         pbi->mb.mb_to_top_edge =
 523         mb_to_top_edge = -((mb_row * 16)) << 3;
 524         mb_to_top_edge -= LEFT_TOP_MARGIN;
 525
 526         pbi->mb.mb_to_bottom_edge =
 527         mb_to_bottom_edge = ((pbi->common.mb_rows - 1 - mb_row) * 16) << 3;
 528         mb_to_bottom_edge += RIGHT_BOTTOM_MARGIN;
 529
 530         while (++mb_col < pbi->common.mb_cols)
 531         {
 532 #if CONFIG_ERROR_CONCEALMENT
 533             int mb_num = mb_row * pbi->common.mb_cols + mb_col;
 534 #endif
 535             /*read_mb_modes_mv(pbi, xd->mode_info_context, &xd->mode_info_context->mbmi, mb_row, mb_col);*/
 536             if(pbi->common.frame_type == KEY_FRAME)
 537                 vp8_kfread_modes(pbi, mi, mb_row, mb_col);
 538             else
 539                 read_mb_modes_mv(pbi, mi, &mi->mbmi, mb_row, mb_col);
 540
 541 #if CONFIG_ERROR_CONCEALMENT
 542             /* look for corruption. set mvs_corrupt_from_mb to the current
 543              * mb_num if the frame is corrupt from this macroblock. */
 544             if (vp8dx_bool_error(&pbi->bc) && mb_num < pbi->mvs_corrupt_from_mb)
 545             {
 546                 pbi->mvs_corrupt_from_mb = mb_num;
 547                 /* no need to continue since the partition is corrupt from
 548                  * here on.
 549                  */
 550                 return;
 551             }
 552 #endif
 553
 554             mi++;       /* next macroblock */
 555         }
 556
 557         mi++;           /* skip left predictor each row */
 558     }
 559 }
 560