src/align.c

   1 /*
   2  *  Copyright 2002, 2004, 2005, 2006, 2007, 2008, 2009 David Hilvert <dhilvert@gmail.com>
   3  *
   4  *  This file is part of libale.
   5  *
   6  *  libale is free software: you can redistribute it and/or modify it under the
   7  *  terms of the GNU Affero General Public License as published by the Free
   8  *  Software Foundation, either version 3 of the License, or (at your option)
   9  *  any later version.
  10  *
  11  *  libale is distributed in the hope that it will be useful, but WITHOUT ANY
  12  *  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  13  *  FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for
  14  *  more details.
  15  *
  16  *  You should have received a copy of the GNU Affero General Public License
  17  *  along with libale.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "libale.h"
  21
  22 /*
  23  * API Implementation.
  24  */
  25
  26 /*
  27  * Types for scale clusters.
  28  */
  29
  30 #if 0
  31
  32 /*
  33  * Experimental non-linear scaling approach.
  34  */
  35
  36 struct nl_scale_cluster {
  37         const image *accum_max;
  38         const image *accum_min;
  39         const image *certainty_max;
  40         const image *certainty_min;
  41         const image *aweight_max;
  42         const image *aweight_min;
  43         exclusion *ax_parameters;
  44
  45         ale_pos input_scale;
  46         const image *input_certainty_max;
  47         const image *input_certainty_min;
  48         const image *input_max;
  49         const image *input_min;
  50 };
  51 #endif
  52
  53 struct scale_cluster {
  54         ale_image accum;
  55         ale_image certainty;
  56         ale_image aweight;
  57         ale_exclusion_list ax_parameters;
  58
  59         ale_pos input_scale;
  60         ale_image input_certainty;
  61         ale_image input;
  62
  63 #if 0
  64         nl_scale_cluster *nl_scale_clusters;
  65 #endif
  66 };
  67
  68
  69 static struct scale_cluster *init_clusters(int frame, ale_pos scale_factor,
  70                 const image *input_frame, unsigned int steps,
  71                 int *local_ax_count) {
  72
  73         /*
  74          * Allocate memory for the array.
  75          */
  76
  77         struct scale_cluster *scale_clusters =
  78                 (struct scale_cluster *) malloc(steps * sizeof(struct scale_cluster));
  79
  80         assert (scale_clusters);
  81
  82         if (!scale_clusters)
  83                 ui::get()->memory_error("alignment");
  84
  85         /*
  86          * Prepare images and exclusion regions for the highest level
  87          * of detail.
  88          */
  89
  90         scale_clusters[0].accum = reference_image;
  91
  92         ui::get()->constructing_lod_clusters(0.0);
  93         scale_clusters[0].input_scale = scale_factor;
  94         if (scale_factor < 1.0 && interpolant == NULL)
  95                 scale_clusters[0].input = input_frame->scale(scale_factor, "alignment");
  96         else
  97                 scale_clusters[0].input = input_frame;
  98
  99         scale_clusters[0].certainty = reference_defined;
 100         scale_clusters[0].aweight = alignment_weights;
 101         scale_clusters[0].ax_parameters = filter_ax_parameters(frame, local_ax_count);
 102
 103         /*
 104          * Allocate and determine input frame certainty.
 105          */
 106
 107         if (scale_clusters[0].input->get_bayer() != IMAGE_BAYER_NONE) {
 108                 scale_clusters[0].input_certainty = new_image_bayer_ale_real(
 109                                 scale_clusters[0].input->height(),
 110                                 scale_clusters[0].input->width(),
 111                                 scale_clusters[0].input->depth(),
 112                                 scale_clusters[0].input->get_bayer());
 113         } else {
 114                 scale_clusters[0].input_certainty = scale_clusters[0].input->clone("certainty");
 115         }
 116
 117         for (unsigned int i = 0; i < scale_clusters[0].input_certainty->height(); i++)
 118         for (unsigned int j = 0; j < scale_clusters[0].input_certainty->width(); j++)
 119         for (unsigned int k = 0; k < 3; k++)
 120         if (scale_clusters[0].input->get_channels(i, j) & (1 << k))
 121                 ((image *) scale_clusters[0].input_certainty)->set_chan(i, j, k,
 122                         scale_clusters[0].input->
 123                                 exp().confidence(scale_clusters[0].input->get_pixel(i, j))[k]);
 124
 125         scale_ax_parameters(*local_ax_count, scale_clusters[0].ax_parameters, scale_factor,
 126                         (scale_factor < 1.0 && interpolant == NULL) ? scale_factor : (ale_pos) 1);
 127
 128         init_nl_cluster(&(scale_clusters[0]));
 129
 130         /*
 131          * Prepare reduced-detail images and exclusion
 132          * regions.
 133          */
 134
 135         for (unsigned int step = 1; step < steps; step++) {
 136                 ui::get()->constructing_lod_clusters(step);
 137                 scale_clusters[step].accum = prepare_lod(scale_clusters[step - 1].accum);
 138                 scale_clusters[step].certainty = prepare_lod_def(scale_clusters[step - 1].certainty);
 139                 scale_clusters[step].aweight = prepare_lod_def(scale_clusters[step - 1].aweight);
 140                 scale_clusters[step].ax_parameters
 141                         = copy_ax_parameters(*local_ax_count, scale_clusters[step - 1].ax_parameters);
 142
 143                 double sf = scale_clusters[step - 1].input_scale / 2;
 144                 scale_clusters[step].input_scale = sf;
 145
 146                 if (sf >= 1.0 || interpolant != NULL) {
 147                         scale_clusters[step].input = scale_clusters[step - 1].input;
 148                         scale_clusters[step].input_certainty = scale_clusters[step - 1].input_certainty;
 149                         scale_ax_parameters(*local_ax_count, scale_clusters[step].ax_parameters, 0.5, 1);
 150                 } else if (sf > 0.5) {
 151                         scale_clusters[step].input = scale_clusters[step - 1].input->scale(sf, "alignment");
 152                         scale_clusters[step].input_certainty = scale_clusters[step - 1].input->scale(sf, "alignment", 1);
 153                         scale_ax_parameters(*local_ax_count, scale_clusters[step].ax_parameters, 0.5, sf);
 154                 } else {
 155                         scale_clusters[step].input = scale_clusters[step - 1].input->scale(0.5, "alignment");
 156                         scale_clusters[step].input_certainty = scale_clusters[step - 1].input_certainty->scale(0.5, "alignment", 1);
 157                         scale_ax_parameters(*local_ax_count, scale_clusters[step].ax_parameters, 0.5, 0.5);
 158                 }
 159
 160                 init_nl_cluster(&(scale_clusters[step]));
 161         }
 162
 163         return scale_clusters;
 164 }
 165
 166 static diff_stat_t _align_element(ale_pos perturb, ale_pos local_lower,
 167                 scale_cluster *scale_clusters, diff_stat_t here,
 168                 ale_pos adj_p, ale_pos adj_o, ale_pos adj_b,
 169                 ale_pos *current_bd, ale_pos *modified_bd,
 170                 astate_t *astate, int lod, scale_cluster si) {
 171
 172         /*
 173          * Run initial tests to get perturbation multipliers and error
 174          * centroids.
 175          */
 176
 177         std::vector<d2::trans_single> t_set;
 178
 179         here.get_perturb_set(&t_set, adj_p, adj_o, adj_b, current_bd, modified_bd);
 180
 181         int stable_count = 0;
 182
 183         while (perturb >= local_lower) {
 184
 185                 ui::get()->alignment_dims(scale_clusters[lod].accum->height(), scale_clusters[lod].accum->width(),
 186                                           scale_clusters[lod].input->height(), scale_clusters[lod].input->width());
 187
 188                 /*
 189                  * Orientational adjustment value in degrees.
 190                  *
 191                  * Since rotational perturbation is now specified as an
 192                  * arclength, we have to convert.
 193                  */
 194
 195                 ale_pos adj_o = 2 * (double) perturb
 196                                   / sqrt(pow(scale_clusters[0].input->height(), 2)
 197                                        + pow(scale_clusters[0].input->width(),  2))
 198                                   * 180
 199                                   / M_PI;
 200
 201                 /*
 202                  * Barrel distortion adjustment value
 203                  */
 204
 205                 ale_pos adj_b = perturb * bda_mult;
 206
 207                 trans_single old_offset = here.get_offset();
 208
 209                 here.perturb_test(perturb, adj_p, adj_o, adj_b, current_bd, modified_bd,
 210                         stable_count);
 211
 212                 if (here.get_offset() == old_offset)
 213                         stable_count++;
 214                 else
 215                         stable_count = 0;
 216
 217                 if (stable_count == 3) {
 218
 219                         stable_count = 0;
 220
 221                         perturb *= 0.5;
 222
 223                         if (lod > 0
 224                          && lod > lrint(log(perturb) / log(2)) - lod_preferred) {
 225
 226                                 /*
 227                                  * Work with images twice as large
 228                                  */
 229
 230                                 lod--;
 231                                 si = scale_clusters[lod];
 232
 233                                 /*
 234                                  * Rescale the transforms.
 235                                  */
 236
 237                                 ale_pos rescale_factor = (double) scale_factor
 238                                                        / (double) pow(2, lod)
 239                                                        / (double) here.get_offset().scale();
 240
 241                                 here.rescale(rescale_factor, si);
 242
 243                         } else {
 244                                 adj_p = perturb / pow(2, lod);
 245                         }
 246
 247                         /*
 248                          * Announce changes
 249                          */
 250
 251                         ui::get()->alignment_perturbation_level(perturb, lod);
 252                 }
 253
 254                 ui::get()->set_match(here.get_error());
 255                 ui::get()->set_offset(here.get_offset());
 256         }
 257
 258         if (lod > 0) {
 259                 ale_pos rescale_factor = (double) scale_factor
 260                                        / (double) here.get_offset().scale();
 261
 262                 here.rescale(rescale_factor, scale_clusters[0]);
 263         }
 264
 265         return here;
 266 }
 267
 268 /*
 269  * Align frame m against the reference.
 270  *
 271  * XXX: the transformation class currently combines ordinary
 272  * transformations with scaling.  This is somewhat convenient for
 273  * some things, but can also be confusing.  This method, _align(), is
 274  * one case where special care must be taken to ensure that the scale
 275  * is always set correctly (by using the 'rescale' method).
 276  */
 277 static diff_stat_multi _align(int m, int local_gs, astate_t *astate) {
 278
 279         const image *input_frame = astate->get_input_frame();
 280
 281         /*
 282          * Local upper/lower data, possibly dependent on image
 283          * dimensions.
 284          */
 285
 286         ale_pos local_lower, local_upper;
 287         ale_accum local_gs_mo;
 288
 289         /*
 290          * Select the minimum dimension as the reference.
 291          */
 292
 293         ale_pos reference_size = input_frame->height();
 294         if (input_frame->width() < reference_size)
 295                 reference_size = input_frame->width();
 296         ale_accum reference_area = input_frame->height()
 297                                  * input_frame->width();
 298
 299         if (perturb_lower_percent)
 300                 local_lower = (double) perturb_lower
 301                             * (double) reference_size
 302                             * (double) 0.01
 303                             * (double) scale_factor;
 304         else
 305                 local_lower = perturb_lower;
 306
 307         if (perturb_upper_percent)
 308                 local_upper = (double) perturb_upper
 309                             * (double) reference_size
 310                             * (double) 0.01
 311                             * (double) scale_factor;
 312         else
 313                 local_upper = perturb_upper;
 314
 315         local_upper = pow(2, floor(log(local_upper) / log(2)));
 316
 317         if (gs_mo_percent)
 318                 local_gs_mo = (double) _gs_mo
 319                             * (double) reference_area
 320                             * (double) 0.01
 321                             * (double) scale_factor;
 322         else
 323                 local_gs_mo = _gs_mo;
 324
 325         /*
 326          * Logarithms aren't exact, so we divide repeatedly to discover
 327          * how many steps will occur, and pass this information to the
 328          * user interface.
 329          */
 330
 331         int step_count = 0;
 332         double step_variable = local_upper;
 333         while (step_variable >= local_lower) {
 334                 step_variable /= 2;
 335                 step_count++;
 336         }
 337
 338         ale_pos perturb = local_upper;
 339
 340         if (_keep) {
 341                 kept_t[latest] = latest_t;
 342                 kept_ok[latest] = latest_ok;
 343         }
 344
 345         /*
 346          * Determine how many levels of detail should be prepared, by
 347          * calculating the initial (largest) value for the
 348          * level-of-detail variable.
 349          */
 350
 351         int lod = lrint(log(perturb) / log(2)) - lod_preferred;
 352
 353         if (lod < 0)
 354                 lod = 0;
 355
 356         while (lod > 0 && (reference_image->width() < pow(2, lod) * min_dimension
 357                         || reference_image->height() < pow(2, lod) * min_dimension))
 358                 lod--;
 359
 360         unsigned int steps = (unsigned int) lod + 1;
 361
 362         /*
 363          * Prepare multiple levels of detail.
 364          */
 365
 366         int local_ax_count;
 367         struct scale_cluster *scale_clusters = init_clusters(m,
 368                         scale_factor, input_frame, steps,
 369                         &local_ax_count);
 370
 371         /*
 372          * Initialize the default initial transform
 373          */
 374
 375         astate->init_default();
 376
 377         /*
 378          * Set the default transformation.
 379          */
 380
 381         transformation offset = astate->get_default();
 382
 383         /*
 384          * Establish boundaries
 385          */
 386
 387         offset.set_current_bounds(reference_image);
 388
 389         ui::get()->alignment_degree_max(offset.get_coordinate(offset.stack_depth() - 1).degree);
 390
 391         if (offset.stack_depth() == 1) {
 392                 ui::get()->set_steps(step_count, 0);
 393         } else {
 394                 ui::get()->set_steps(offset.get_coordinate(offset.stack_depth() - 1).degree + 1, 1);
 395         }
 396
 397         /*
 398          * Load any file-specified transformations
 399          */
 400
 401         for (unsigned int index = 0; index < offset.stack_depth(); index++) {
 402                 int is_default = 1;
 403                 unsigned int index_2;
 404                 offset.set_current_index(index);
 405
 406                 offset = tload_next(tload, alignment_class == 2,
 407                                 offset,
 408                                 &is_default, offset.get_current_index() == 0);
 409
 410                 index_2 = offset.get_current_index();
 411
 412                 if (index_2 > index) {
 413                         for (unsigned int index_3 = index; index_3 < index_2; index_3++)
 414                                 astate->set_is_default(index_3, 1);
 415
 416                         index = index_2;
 417                 }
 418
 419                 astate->set_is_default(index, is_default);
 420         }
 421
 422         offset.set_current_index(0);
 423
 424         astate->init_frame_alignment_primary(&offset, lod, perturb);
 425
 426         /*
 427          * Control point alignment
 428          */
 429
 430         if (local_gs == 5) {
 431
 432                 transformation o = offset;
 433
 434                 /*
 435                  * Determine centroid data
 436                  */
 437
 438                 point current, previous;
 439                 centroids(m, &current, &previous);
 440
 441                 if (current.defined() && previous.defined()) {
 442                         o = orig_t;
 443                         o.set_dimensions(input_frame);
 444                         o.translate((previous - current) * o.scale());
 445                         current = previous;
 446                 }
 447
 448                 /*
 449                  * Determine rotation for alignment classes other than translation.
 450                  */
 451
 452                 ale_pos lowest_error = cp_rms_error(m, o);
 453
 454                 ale_pos rot_lower = 2 * (double) local_lower
 455                                   / sqrt(pow(scale_clusters[0].input->height(), 2)
 456                                        + pow(scale_clusters[0].input->width(),  2))
 457                                   * 180
 458                                   / M_PI;
 459
 460                 if  (alignment_class > 0)
 461                 for (double rot = 30; rot > rot_lower; rot /= 2)
 462                 for (double srot = -rot; srot < rot * 1.5; srot += rot * 2) {
 463                         int is_improved = 1;
 464                         while (is_improved) {
 465                                 is_improved = 0;
 466                                 transformation test_t = o;
 467                                 /*
 468                                  * XXX: is this right?
 469                                  */
 470                                 test_t.rotate(current * o.scale(), srot);
 471                                 ale_pos test_v = cp_rms_error(m, test_t);
 472
 473                                 if (test_v < lowest_error) {
 474                                         lowest_error = test_v;
 475                                         o = test_t;
 476                                         srot += 3 * rot;
 477                                         is_improved = 1;
 478                                 }
 479                         }
 480                 }
 481
 482                 /*
 483                  * Determine projective parameters through a local
 484                  * minimum search.
 485                  */
 486
 487                 if (alignment_class == 2) {
 488                         ale_pos adj_p = lowest_error;
 489
 490                         if (adj_p < local_lower)
 491                                 adj_p = local_lower;
 492
 493                         while (adj_p >= local_lower) {
 494                                 transformation test_t = o;
 495                                 int is_improved = 1;
 496                                 ale_pos test_v;
 497                                 ale_pos adj_s;
 498
 499                                 while (is_improved) {
 500                                         is_improved = 0;
 501
 502                                         for (int i = 0; i < 4; i++)
 503                                         for (int j = 0; j < 2; j++)
 504                                         for (adj_s = -adj_p; adj_s <= adj_p; adj_s += 2 * adj_p) {
 505
 506                                                 test_t = o;
 507
 508                                                 if (perturb_type == 0)
 509                                                         test_t.gpt_modify(j, i, adj_s);
 510                                                 else if (perturb_type == 1)
 511                                                         test_t.gr_modify(j, i, adj_s);
 512                                                 else
 513                                                         assert(0);
 514
 515                                                 test_v = cp_rms_error(m, test_t);
 516
 517                                                 if (test_v < lowest_error) {
 518                                                         lowest_error = test_v;
 519                                                         o = test_t;
 520                                                         adj_s += 3 * adj_p;
 521                                                         is_improved = 1;
 522                                                 }
 523                                         }
 524                                 }
 525                                 adj_p /= 2;
 526                         }
 527                 }
 528         }
 529
 530         /*
 531          * Pre-alignment exposure adjustment
 532          */
 533
 534         if (_exp_register) {
 535                 ui::get()->exposure_1();
 536                 set_exposure_ratio(m, scale_clusters[0], offset, local_ax_count, 0);
 537         }
 538
 539         /*
 540          * Scale transform for lod
 541          */
 542
 543         for (int lod_ = 0; lod_ < lod; lod_++) {
 544                 transformation s = offset;
 545                 transformation t = offset;
 546
 547                 t.rescale(1 / (double) 2);
 548
 549                 if (!(t.scaled_height() > 0 && t.scaled_height() < s.scaled_height())
 550                  || !(t.scaled_width() > 0  && t.scaled_width() < s.scaled_width())) {
 551                         perturb /= pow(2, lod - lod_);
 552                         lod = lod_;
 553                         break;
 554                 } else {
 555                         offset = t;
 556                 }
 557         }
 558
 559         ui::get()->set_offset(offset);
 560
 561         struct scale_cluster si = scale_clusters[lod];
 562
 563         /*
 564          * Projective adjustment value
 565          */
 566
 567         ale_pos adj_p = perturb / pow(2, lod);
 568
 569         /*
 570          * Orientational adjustment value in degrees.
 571          *
 572          * Since rotational perturbation is now specified as an
 573          * arclength, we have to convert.
 574          */
 575
 576         ale_pos adj_o = (double) 2 * (double) perturb
 577                           / sqrt(pow((double) scale_clusters[0].input->height(), (double) 2)
 578                                + pow((double) scale_clusters[0].input->width(),  (double) 2))
 579                           * (double) 180
 580                           / M_PI;
 581
 582         /*
 583          * Barrel distortion adjustment value
 584          */
 585
 586         ale_pos adj_b = perturb * bda_mult;
 587
 588         /*
 589          * Global search overlap requirements.
 590          */
 591
 592         local_gs_mo = (double) local_gs_mo / pow(pow(2, lod), 2);
 593
 594         /*
 595          * Alignment statistics.
 596          */
 597
 598         diff_stat_t here(offset.elem_bounds());
 599
 600         /*
 601          * Current difference (error) value
 602          */
 603
 604         ui::get()->prematching();
 605         here.diff(si, offset.get_current_element(), local_ax_count, m);
 606         ui::get()->set_match(here.get_error());
 607
 608         /*
 609          * Current and modified barrel distortion parameters
 610          */
 611
 612         ale_pos current_bd[BARREL_DEGREE];
 613         ale_pos modified_bd[BARREL_DEGREE];
 614         offset.bd_get(current_bd);
 615         offset.bd_get(modified_bd);
 616
 617         /*
 618          * Translational global search step
 619          */
 620
 621         if (perturb >= local_lower && local_gs != 0 && local_gs != 5
 622          && (local_gs != 6 || astate->get_is_default(0))) {
 623
 624                 ui::get()->global_alignment(perturb, lod);
 625                 ui::get()->gs_mo(local_gs_mo);
 626
 627                 test_globals(&here, si, offset, local_gs, adj_p,
 628                                 local_ax_count, m, local_gs_mo, perturb);
 629
 630                 ui::get()->set_match(here.get_error());
 631                 ui::get()->set_offset(here.get_offset());
 632         }
 633
 634         /*
 635          * Perturbation adjustment loop.
 636          */
 637
 638         offset.set_current_element(here.get_offset());
 639
 640         for (unsigned int i = 0; i < offset.stack_depth(); i++) {
 641
 642                 ui::get()->aligning_element(i, offset.stack_depth());
 643
 644                 offset.set_current_index(i);
 645
 646                 ui::get()->start_multi_alignment_element(offset);
 647
 648                 ui::get()->set_offset(offset);
 649
 650                 if (i > 0) {
 651                         astate->init_frame_alignment_nonprimary(&offset, lod, perturb, i);
 652
 653                         if (_exp_register == 1) {
 654                                 ui::get()->exposure_1();
 655                                 pixel_accum asum(0, 0, 0), bsum(0, 0, 0);
 656                                 exposure_ratio_iterate eri(&asum, &bsum, scale_clusters[0], offset, local_ax_count, 0,
 657                                         offset.elem_bounds().scale_to_bounds(scale_clusters[0].accum->height(),
 658                                                                              scale_clusters[0].accum->width()));
 659
 660                                 eri.run();
 661                                 pixel_accum tr = asum / bsum;
 662                                 ui::get()->exp_multiplier(tr[0], tr[1], tr[2]);
 663                                 offset.set_tonal_multiplier(tr);
 664                         }
 665                 }
 666
 667                 int e_lod = lod;
 668                 int e_div = offset.get_current_coordinate().degree;
 669                 ale_pos e_perturb = perturb;
 670                 ale_pos e_adj_p = adj_p;
 671                 ale_pos e_adj_b = adj_b;
 672
 673                 for (int d = 0; d < e_div; d++) {
 674                         e_adj_b = 0;
 675                         e_perturb *= 0.5;
 676                         if (e_lod > 0) {
 677                                 e_lod--;
 678                         } else {
 679                                 e_adj_p *= 0.5;
 680                         }
 681                 }
 682
 683                 if (i > 0) {
 684
 685                         d2::trans_multi::elem_bounds_t b = offset.elem_bounds();
 686
 687                         for (int dim_satisfied = 0; e_lod > 0 && !dim_satisfied; ) {
 688                                 int height = scale_clusters[e_lod].accum->height();
 689                                 int width = scale_clusters[e_lod].accum->width();
 690
 691                                 d2::trans_multi::elem_bounds_int_t bi = b.scale_to_bounds(height, width);
 692
 693                                 dim_satisfied = bi.satisfies_min_dim(min_dimension);
 694
 695                                 if (!dim_satisfied) {
 696                                         e_lod--;
 697                                         e_adj_p *= 2;
 698                                 }
 699                         }
 700
 701                         /*
 702                          * Scale transform for lod
 703                          */
 704
 705                         for (int lod_ = 0; lod_ < e_lod; lod_++) {
 706                                 trans_single s = offset.get_element(i);
 707                                 trans_single t = offset.get_element(i);
 708
 709                                 t.rescale(1 / (double) 2);
 710
 711                                 if (!(t.scaled_height() > 0 && t.scaled_height() < s.scaled_height())
 712                                  || !(t.scaled_width() > 0  && t.scaled_width() < s.scaled_width())) {
 713                                         e_perturb /= pow(2, e_lod - lod_);
 714                                         e_lod = lod_;
 715                                         break;
 716                                 } else {
 717                                         offset.set_element(i, t);
 718                                 }
 719                         }
 720
 721                         ui::get()->set_offset(offset);
 722                 }
 723
 724                 /*
 725                  * Announce perturbation size
 726                  */
 727
 728                 ui::get()->aligning(e_perturb, e_lod);
 729
 730                 si = scale_clusters[e_lod];
 731
 732                 here.set_elem_bounds(offset.elem_bounds());
 733
 734                 here.diff(si, offset.get_current_element(), local_ax_count, m);
 735
 736                 here.confirm();
 737
 738                 here = check_ancestor_path(offset, si, here, local_ax_count, m);
 739
 740                 here = _align_element(e_perturb, local_lower, scale_clusters,
 741                                 here, e_adj_p, adj_o, e_adj_b, current_bd, modified_bd,
 742                                 astate, e_lod, si);
 743
 744                 offset.rescale(here.get_offset().scale() / offset.scale());
 745
 746                 offset.set_current_element(here.get_offset());
 747
 748                 if (i > 0 && _exp_register == 1) {
 749                         if (ma_cert_satisfied(scale_clusters[0], offset, i)) {
 750                                 ui::get()->exposure_2();
 751                                 pixel_accum asum(0, 0, 0), bsum(0, 0, 0);
 752                                 exposure_ratio_iterate eri(&asum, &bsum, scale_clusters[0], offset, local_ax_count, 1,
 753                                         offset.elem_bounds().scale_to_bounds(scale_clusters[0].accum->height(),
 754                                                                              scale_clusters[0].accum->width()));
 755
 756                                 eri.run();
 757                                 pixel_accum tr = asum / bsum;
 758                                 ui::get()->exp_multiplier(tr[0], tr[1], tr[2]);
 759                                 offset.set_tonal_multiplier(tr);
 760                         } else {
 761                                 offset.set_tonal_multiplier(offset.get_element(offset.parent_index(i)).get_tonal_multiplier(point(0, 0)));
 762                         }
 763                 } else if (_exp_register == 1) {
 764                         ui::get()->exposure_2();
 765                         set_exposure_ratio(m, scale_clusters[0], offset, local_ax_count, 1);
 766                 }
 767
 768                 ui::get()->set_offset(offset);
 769
 770                 if (i + 1 == offset.stack_depth())
 771                         ui::get()->alignment_degree_complete(offset.get_coordinate(i).degree);
 772                 else if (offset.get_coordinate(i).degree != offset.get_coordinate(i + 1).degree)
 773                         ui::get()->alignment_degree_complete(offset.get_coordinate(i + 1).degree);
 774         }
 775
 776         offset.set_current_index(0);
 777
 778         ui::get()->multi();
 779         offset.set_multi(reference_image, input_frame);
 780
 781         /*
 782          * Recalculate error on whole frame.
 783          */
 784
 785         ui::get()->postmatching();
 786         diff_stat_generic<transformation> multi_here(offset.elem_bounds());
 787         multi_here.diff(scale_clusters[0], offset, local_ax_count, m);
 788         ui::get()->set_match(multi_here.get_error());
 789
 790         /*
 791          * Free the level-of-detail structures
 792          */
 793
 794         final_clusters(scale_clusters, scale_factor, steps);
 795
 796         /*
 797          * Ensure that the match meets the threshold.
 798          */
 799
 800         if (threshold_ok(multi_here.get_error())) {
 801                 /*
 802                  * Update alignment variables
 803                  */
 804                 latest_ok = 1;
 805                 astate->set_default(offset);
 806                 astate->set_final(offset);
 807                 ui::get()->alignment_match_ok();
 808         } else if (local_gs == 4) {
 809
 810                 /*
 811                  * Align with outer starting points.
 812                  */
 813
 814                 /*
 815                  * XXX: This probably isn't exactly the right thing to do,
 816                  * since variables like old_initial_value have been overwritten.
 817                  */
 818
 819                 diff_stat_multi nested_result = _align(m, -1, astate);
 820
 821                 if (threshold_ok(nested_result.get_error())) {
 822                         return nested_result;
 823                 } else if (nested_result.get_error() < multi_here.get_error()) {
 824                         multi_here = nested_result;
 825                 }
 826
 827                 if (is_fail_default)
 828                         offset = astate->get_default();
 829
 830                 ui::get()->set_match(multi_here.get_error());
 831                 ui::get()->alignment_no_match();
 832
 833         } else if (local_gs == -1) {
 834
 835                 latest_ok = 0;
 836                 latest_t = offset;
 837                 return multi_here;
 838
 839         } else {
 840                 if (is_fail_default)
 841                         offset = astate->get_default();
 842                 latest_ok = 0;
 843                 ui::get()->alignment_no_match();
 844         }
 845
 846         /*
 847          * Write the tonal registration multiplier as a comment.
 848          */
 849
 850         pixel trm = image_rw::exp(m).get_multiplier();
 851         tsave_trm(tsave, trm[0], trm[1], trm[2]);
 852
 853         /*
 854          * Save the transformation information
 855          */
 856
 857         for (unsigned int index = 0; index < offset.stack_depth(); index++) {
 858                 offset.set_current_index(index);
 859
 860                 tsave_next(tsave, offset, alignment_class == 2,
 861                                   offset.get_current_index() == 0);
 862         }
 863
 864         offset.set_current_index(0);
 865
 866         /*
 867          * Update match statistics.
 868          */
 869
 870         match_sum += (1 - multi_here.get_error()) * (ale_accum) 100;
 871         match_count++;
 872         latest = m;
 873         latest_t = offset;
 874
 875         return multi_here;
 876 }
 877
 878 int ale_align(ale_image a, ale_image b, ale_trans start,
 879                 ale_align_properties align_properties, ale_trans result) {
 880 #warning function unfinished.
 881 }
 882