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comparison mupdf-source/thirdparty/tesseract/src/textord/colfind.cpp @ 2:b50eed0cc0ef upstream

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ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
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1:1d09e1dec1d9 2:b50eed0cc0ef
1 ///////////////////////////////////////////////////////////////////////
2 // File: colfind.cpp
3 // Description: Class to hold BLOBNBOXs in a grid for fast access
4 // to neighbours.
5 // Author: Ray Smith
6 //
7 // (C) Copyright 2007, Google Inc.
8 // Licensed under the Apache License, Version 2.0 (the "License");
9 // you may not use this file except in compliance with the License.
10 // You may obtain a copy of the License at
11 // http://www.apache.org/licenses/LICENSE-2.0
12 // Unless required by applicable law or agreed to in writing, software
13 // distributed under the License is distributed on an "AS IS" BASIS,
14 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 // See the License for the specific language governing permissions and
16 // limitations under the License.
17 //
18 ///////////////////////////////////////////////////////////////////////
19
20 // Include automatically generated configuration file if running autoconf.
21 #ifdef HAVE_CONFIG_H
22 # include "config_auto.h"
23 #endif
24
25 #include "colfind.h"
26
27 #include "ccnontextdetect.h"
28 #include "colpartition.h"
29 #include "colpartitionset.h"
30 #ifndef DISABLED_LEGACY_ENGINE
31 # include "equationdetectbase.h"
32 #endif
33 #include "blobbox.h"
34 #include "linefind.h"
35 #include "normalis.h"
36 #include "params.h"
37 #include "scrollview.h"
38 #include "strokewidth.h"
39 #include "tablefind.h"
40 #include "workingpartset.h"
41
42 #include <algorithm>
43
44 namespace tesseract {
45
46 // When assigning columns, the max number of misfit grid rows/ColPartitionSets
47 // that can be ignored.
48 const int kMaxIncompatibleColumnCount = 2;
49 // Max fraction of mean_column_gap_ for the gap between two partitions within a
50 // column to allow them to merge.
51 const double kHorizontalGapMergeFraction = 0.5;
52 // Minimum gutter width as a fraction of gridsize
53 const double kMinGutterWidthGrid = 0.5;
54 // Max multiple of a partition's median size as a distance threshold for
55 // adding noise blobs.
56 const double kMaxDistToPartSizeRatio = 1.5;
57
58 #ifndef GRAPHICS_DISABLED
59 static BOOL_VAR(textord_tabfind_show_initial_partitions, false, "Show partition bounds");
60 static BOOL_VAR(textord_tabfind_show_reject_blobs, false, "Show blobs rejected as noise");
61 static INT_VAR(textord_tabfind_show_partitions, 0,
62 "Show partition bounds, waiting if >1 (ScrollView)");
63 static BOOL_VAR(textord_tabfind_show_columns, false, "Show column bounds (ScrollView)");
64 static BOOL_VAR(textord_tabfind_show_blocks, false, "Show final block bounds (ScrollView)");
65 #endif
66 static BOOL_VAR(textord_tabfind_find_tables, true, "run table detection");
67
68 #ifndef GRAPHICS_DISABLED
69 ScrollView *ColumnFinder::blocks_win_ = nullptr;
70 #endif
71
72 // Gridsize is an estimate of the text size in the image. A suitable value
73 // is in TO_BLOCK::line_size after find_components has been used to make
74 // the blobs.
75 // bleft and tright are the bounds of the image (or rectangle) being processed.
76 // vlines is a (possibly empty) list of TabVector and vertical_x and y are
77 // the sum logical vertical vector produced by LineFinder::FindVerticalLines.
78 ColumnFinder::ColumnFinder(int gridsize, const ICOORD &bleft, const ICOORD &tright, int resolution,
79 bool cjk_script, double aligned_gap_fraction, TabVector_LIST *vlines,
80 TabVector_LIST *hlines, int vertical_x, int vertical_y)
81 : TabFind(gridsize, bleft, tright, vlines, vertical_x, vertical_y, resolution)
82 , cjk_script_(cjk_script)
83 , min_gutter_width_(static_cast<int>(kMinGutterWidthGrid * gridsize))
84 , mean_column_gap_(tright.x() - bleft.x())
85 , tabfind_aligned_gap_fraction_(aligned_gap_fraction)
86 , deskew_(0.0f, 0.0f)
87 , reskew_(1.0f, 0.0f)
88 , rotation_(1.0f, 0.0f)
89 , rerotate_(1.0f, 0.0f)
90 , text_rotation_(0.0f, 0.0f)
91 , best_columns_(nullptr)
92 , stroke_width_(nullptr)
93 , part_grid_(gridsize, bleft, tright)
94 , nontext_map_(nullptr)
95 , projection_(resolution)
96 , denorm_(nullptr)
97 , equation_detect_(nullptr) {
98 TabVector_IT h_it(&horizontal_lines_);
99 h_it.add_list_after(hlines);
100 }
101
102 ColumnFinder::~ColumnFinder() {
103 for (auto set : column_sets_) {
104 delete set;
105 }
106 delete[] best_columns_;
107 delete stroke_width_;
108 #ifndef GRAPHICS_DISABLED
109 delete input_blobs_win_;
110 #endif
111 nontext_map_.destroy();
112 while (denorm_ != nullptr) {
113 DENORM *dead_denorm = denorm_;
114 denorm_ = const_cast<DENORM *>(denorm_->predecessor());
115 delete dead_denorm;
116 }
117
118 // The ColPartitions are destroyed automatically, but any boxes in
119 // the noise_parts_ list are owned and need to be deleted explicitly.
120 ColPartition_IT part_it(&noise_parts_);
121 for (part_it.mark_cycle_pt(); !part_it.cycled_list(); part_it.forward()) {
122 ColPartition *part = part_it.data();
123 part->DeleteBoxes();
124 }
125 // Likewise any boxes in the good_parts_ list need to be deleted.
126 // These are just the image parts. Text parts have already given their
127 // boxes on to the TO_BLOCK, and have empty lists.
128 part_it.set_to_list(&good_parts_);
129 for (part_it.mark_cycle_pt(); !part_it.cycled_list(); part_it.forward()) {
130 ColPartition *part = part_it.data();
131 part->DeleteBoxes();
132 }
133 // Also, any blobs on the image_bblobs_ list need to have their cblobs
134 // deleted. This only happens if there has been an early return from
135 // FindColumns, as in a normal return, the blobs go into the grid and
136 // end up in noise_parts_, good_parts_ or the output blocks.
137 BLOBNBOX_IT bb_it(&image_bblobs_);
138 for (bb_it.mark_cycle_pt(); !bb_it.cycled_list(); bb_it.forward()) {
139 BLOBNBOX *bblob = bb_it.data();
140 delete bblob->cblob();
141 }
142 }
143
144 // Performs initial processing on the blobs in the input_block:
145 // Setup the part_grid_, stroke_width_, nontext_map.
146 // Obvious noise blobs are filtered out and used to mark the nontext_map_.
147 // Initial stroke-width analysis is used to get local text alignment
148 // direction, so the textline projection_ map can be setup.
149 // On return, IsVerticallyAlignedText may be called (now optionally) to
150 // determine the gross textline alignment of the page.
151 void ColumnFinder::SetupAndFilterNoise(PageSegMode pageseg_mode, Image photo_mask_pix,
152 TO_BLOCK *input_block) {
153 part_grid_.Init(gridsize(), bleft(), tright());
154 delete stroke_width_;
155 stroke_width_ = new StrokeWidth(gridsize(), bleft(), tright());
156 min_gutter_width_ = static_cast<int>(kMinGutterWidthGrid * gridsize());
157 input_block->ReSetAndReFilterBlobs();
158 #ifndef GRAPHICS_DISABLED
159 if (textord_tabfind_show_blocks) {
160 input_blobs_win_ = MakeWindow(0, 0, "Filtered Input Blobs");
161 input_block->plot_graded_blobs(input_blobs_win_);
162 }
163 #endif // !GRAPHICS_DISABLED
164 SetBlockRuleEdges(input_block);
165 nontext_map_.destroy();
166 // Run a preliminary strokewidth neighbour detection on the medium blobs.
167 stroke_width_->SetNeighboursOnMediumBlobs(input_block);
168 CCNonTextDetect nontext_detect(gridsize(), bleft(), tright());
169 // Remove obvious noise and make the initial non-text map.
170 nontext_map_ =
171 nontext_detect.ComputeNonTextMask(textord_debug_tabfind, photo_mask_pix, input_block);
172 stroke_width_->FindTextlineDirectionAndFixBrokenCJK(pageseg_mode, cjk_script_, input_block);
173 // Clear the strokewidth grid ready for rotation or leader finding.
174 stroke_width_->Clear();
175 }
176
177 // Tests for vertical alignment of text (returning true if so), and generates
178 // a list of blobs of moderate aspect ratio, in the most frequent writing
179 // direction (in osd_blobs) for orientation and script detection to test
180 // the character orientation.
181 // block is the single block for the whole page or rectangle to be OCRed.
182 // Note that the vertical alignment may be due to text whose writing direction
183 // is vertical, like say Japanese, or due to text whose writing direction is
184 // horizontal but whose text appears vertically aligned because the image is
185 // not the right way up.
186 bool ColumnFinder::IsVerticallyAlignedText(double find_vertical_text_ratio, TO_BLOCK *block,
187 BLOBNBOX_CLIST *osd_blobs) {
188 return stroke_width_->TestVerticalTextDirection(find_vertical_text_ratio, block, osd_blobs);
189 }
190
191 // Rotates the blobs and the TabVectors so that the gross writing direction
192 // (text lines) are horizontal and lines are read down the page.
193 // Applied rotation stored in rotation_.
194 // A second rotation is calculated for application during recognition to
195 // make the rotated blobs upright for recognition.
196 // Subsequent rotation stored in text_rotation_.
197 //
198 // Arguments:
199 // vertical_text_lines true if the text lines are vertical.
200 // recognition_rotation [0..3] is the number of anti-clockwise 90 degree
201 // rotations from osd required for the text to be upright and readable.
202 void ColumnFinder::CorrectOrientation(TO_BLOCK *block, bool vertical_text_lines,
203 int recognition_rotation) {
204 const FCOORD anticlockwise90(0.0f, 1.0f);
205 const FCOORD clockwise90(0.0f, -1.0f);
206 const FCOORD rotation180(-1.0f, 0.0f);
207 const FCOORD norotation(1.0f, 0.0f);
208
209 text_rotation_ = norotation;
210 // Rotate the page to make the text upright, as implied by
211 // recognition_rotation.
212 rotation_ = norotation;
213 if (recognition_rotation == 1) {
214 rotation_ = anticlockwise90;
215 } else if (recognition_rotation == 2) {
216 rotation_ = rotation180;
217 } else if (recognition_rotation == 3) {
218 rotation_ = clockwise90;
219 }
220 // We infer text writing direction to be vertical if there are several
221 // vertical text lines detected, and horizontal if not. But if the page
222 // orientation was determined to be 90 or 270 degrees, the true writing
223 // direction is the opposite of what we inferred.
224 if (recognition_rotation & 1) {
225 vertical_text_lines = !vertical_text_lines;
226 }
227 // If we still believe the writing direction is vertical, we use the
228 // convention of rotating the page ccw 90 degrees to make the text lines
229 // horizontal, and mark the blobs for rotation cw 90 degrees for
230 // classification so that the text order is correct after recognition.
231 if (vertical_text_lines) {
232 rotation_.rotate(anticlockwise90);
233 text_rotation_.rotate(clockwise90);
234 }
235 // Set rerotate_ to the inverse of rotation_.
236 rerotate_ = FCOORD(rotation_.x(), -rotation_.y());
237 if (rotation_.x() != 1.0f || rotation_.y() != 0.0f) {
238 // Rotate all the blobs and tab vectors.
239 RotateBlobList(rotation_, &block->large_blobs);
240 RotateBlobList(rotation_, &block->blobs);
241 RotateBlobList(rotation_, &block->small_blobs);
242 RotateBlobList(rotation_, &block->noise_blobs);
243 TabFind::ResetForVerticalText(rotation_, rerotate_, &horizontal_lines_, &min_gutter_width_);
244 part_grid_.Init(gridsize(), bleft(), tright());
245 // Reset all blobs to initial state and filter by size.
246 // Since they have rotated, the list they belong on could have changed.
247 block->ReSetAndReFilterBlobs();
248 SetBlockRuleEdges(block);
249 stroke_width_->CorrectForRotation(rerotate_, &part_grid_);
250 }
251 if (textord_debug_tabfind) {
252 tprintf("Vertical=%d, orientation=%d, final rotation=(%f, %f)+(%f,%f)\n", vertical_text_lines,
253 recognition_rotation, rotation_.x(), rotation_.y(), text_rotation_.x(),
254 text_rotation_.y());
255 }
256 // Setup the denormalization.
257 ASSERT_HOST(denorm_ == nullptr);
258 denorm_ = new DENORM;
259 denorm_->SetupNormalization(nullptr, &rotation_, nullptr, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f);
260 }
261
262 // Finds blocks of text, image, rule line, table etc, returning them in the
263 // blocks and to_blocks
264 // (Each TO_BLOCK points to the basic BLOCK and adds more information.)
265 // Image blocks are generated by a combination of photo_mask_pix (which may
266 // NOT be nullptr) and the rejected text found during preliminary textline
267 // finding.
268 // The input_block is the result of a call to find_components, and contains
269 // the blobs found in the image or rectangle to be OCRed. These blobs will be
270 // removed and placed in the output blocks, while unused ones will be deleted.
271 // If single_column is true, the input is treated as single column, but
272 // it is still divided into blocks of equal line spacing/text size.
273 // scaled_color is scaled down by scaled_factor from the input color image,
274 // and may be nullptr if the input was not color.
275 // grey_pix is optional, but if present must match the photo_mask_pix in size,
276 // and must be a *real* grey image instead of binary_pix * 255.
277 // thresholds_pix is expected to be present iff grey_pix is present and
278 // can be an integer factor reduction of the grey_pix. It represents the
279 // thresholds that were used to create the binary_pix from the grey_pix.
280 // If diacritic_blobs is non-null, then diacritics/noise blobs, that would
281 // confuse layout analysis by causing textline overlap, are placed there,
282 // with the expectation that they will be reassigned to words later and
283 // noise/diacriticness determined via classification.
284 // Returns -1 if the user hits the 'd' key in the blocks window while running
285 // in debug mode, which requests a retry with more debug info.
286 int ColumnFinder::FindBlocks(PageSegMode pageseg_mode, Image scaled_color, int scaled_factor,
287 TO_BLOCK *input_block, Image photo_mask_pix, Image thresholds_pix,
288 Image grey_pix, DebugPixa *pixa_debug, BLOCK_LIST *blocks,
289 BLOBNBOX_LIST *diacritic_blobs, TO_BLOCK_LIST *to_blocks) {
290 photo_mask_pix |= nontext_map_;
291 stroke_width_->FindLeaderPartitions(input_block, &part_grid_);
292 stroke_width_->RemoveLineResidue(&big_parts_);
293 FindInitialTabVectors(nullptr, min_gutter_width_, tabfind_aligned_gap_fraction_, input_block);
294 SetBlockRuleEdges(input_block);
295 stroke_width_->GradeBlobsIntoPartitions(pageseg_mode, rerotate_, input_block, nontext_map_,
296 denorm_, cjk_script_, &projection_, diacritic_blobs,
297 &part_grid_, &big_parts_);
298 if (!PSM_SPARSE(pageseg_mode)) {
299 ImageFind::FindImagePartitions(photo_mask_pix, rotation_, rerotate_, input_block, this,
300 pixa_debug, &part_grid_, &big_parts_);
301 ImageFind::TransferImagePartsToImageMask(rerotate_, &part_grid_, photo_mask_pix);
302 ImageFind::FindImagePartitions(photo_mask_pix, rotation_, rerotate_, input_block, this,
303 pixa_debug, &part_grid_, &big_parts_);
304 }
305 part_grid_.ReTypeBlobs(&image_bblobs_);
306 TidyBlobs(input_block);
307 Reset();
308 // TODO(rays) need to properly handle big_parts_.
309 ColPartition_IT p_it(&big_parts_);
310 for (p_it.mark_cycle_pt(); !p_it.cycled_list(); p_it.forward()) {
311 p_it.data()->DisownBoxesNoAssert();
312 }
313 big_parts_.clear();
314 delete stroke_width_;
315 stroke_width_ = nullptr;
316 // Compute the edge offsets whether or not there is a grey_pix. It is done
317 // here as the c_blobs haven't been touched by rotation or anything yet,
318 // so no denorm is required, yet the text has been separated from image, so
319 // no time is wasted running it on image blobs.
320 input_block->ComputeEdgeOffsets(thresholds_pix, grey_pix);
321
322 // A note about handling right-to-left scripts (Hebrew/Arabic):
323 // The columns must be reversed and come out in right-to-left instead of
324 // the normal left-to-right order. Because the left-to-right ordering
325 // is implicit in many data structures, it is simpler to fool the algorithms
326 // into thinking they are dealing with left-to-right text.
327 // To do this, we reflect the needed data in the y-axis and then reflect
328 // the blocks back after they have been created. This is a temporary
329 // arrangement that is confined to this function only, so the reflection
330 // is completely invisible in the output blocks.
331 // The only objects reflected are:
332 // The vertical separator lines that have already been found;
333 // The bounding boxes of all BLOBNBOXES on all lists on the input_block
334 // plus the image_bblobs. The outlines are not touched, since they are
335 // not looked at.
336 bool input_is_rtl = input_block->block->right_to_left();
337 if (input_is_rtl) {
338 // Reflect the vertical separator lines (member of TabFind).
339 ReflectInYAxis();
340 // Reflect the blob boxes.
341 ReflectForRtl(input_block, &image_bblobs_);
342 part_grid_.ReflectInYAxis();
343 }
344
345 if (!PSM_SPARSE(pageseg_mode)) {
346 if (!PSM_COL_FIND_ENABLED(pageseg_mode)) {
347 // No tab stops needed. Just the grid that FindTabVectors makes.
348 DontFindTabVectors(&image_bblobs_, input_block, &deskew_, &reskew_);
349 } else {
350 SetBlockRuleEdges(input_block);
351 // Find the tab stops, estimate skew, and deskew the tabs, blobs and
352 // part_grid_.
353 FindTabVectors(&horizontal_lines_, &image_bblobs_, input_block, min_gutter_width_,
354 tabfind_aligned_gap_fraction_, &part_grid_, &deskew_, &reskew_);
355 // Add the deskew to the denorm_.
356 auto *new_denorm = new DENORM;
357 new_denorm->SetupNormalization(nullptr, &deskew_, denorm_, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f,
358 0.0f);
359 denorm_ = new_denorm;
360 }
361 SetBlockRuleEdges(input_block);
362 part_grid_.SetTabStops(this);
363
364 // Make the column_sets_.
365 if (!MakeColumns(false)) {
366 tprintf("Empty page!!\n");
367 part_grid_.DeleteParts();
368 return 0; // This is an empty page.
369 }
370
371 // Refill the grid using rectangular spreading, and get the benefit
372 // of the completed tab vectors marking the rule edges of each blob.
373 Clear();
374 #ifndef GRAPHICS_DISABLED
375 if (textord_tabfind_show_reject_blobs) {
376 ScrollView *rej_win = MakeWindow(500, 300, "Rejected blobs");
377 input_block->plot_graded_blobs(rej_win);
378 }
379 #endif // !GRAPHICS_DISABLED
380 InsertBlobsToGrid(false, false, &image_bblobs_, this);
381 InsertBlobsToGrid(true, true, &input_block->blobs, this);
382
383 part_grid_.GridFindMargins(best_columns_);
384 // Split and merge the partitions by looking at local neighbours.
385 GridSplitPartitions();
386 // Resolve unknown partitions by adding to an existing partition, fixing
387 // the type, or declaring them noise.
388 part_grid_.GridFindMargins(best_columns_);
389 GridMergePartitions();
390 // Insert any unused noise blobs that are close enough to an appropriate
391 // partition.
392 InsertRemainingNoise(input_block);
393 // Add horizontal line separators as partitions.
394 GridInsertHLinePartitions();
395 GridInsertVLinePartitions();
396 // Recompute margins based on a local neighbourhood search.
397 part_grid_.GridFindMargins(best_columns_);
398 SetPartitionTypes();
399 }
400 #ifndef GRAPHICS_DISABLED
401 if (textord_tabfind_show_initial_partitions) {
402 ScrollView *part_win = MakeWindow(100, 300, "InitialPartitions");
403 part_grid_.DisplayBoxes(part_win);
404 DisplayTabVectors(part_win);
405 }
406 #endif
407 if (!PSM_SPARSE(pageseg_mode)) {
408 #ifndef DISABLED_LEGACY_ENGINE
409 if (equation_detect_) {
410 equation_detect_->FindEquationParts(&part_grid_, best_columns_);
411 }
412 #endif
413 if (textord_tabfind_find_tables) {
414 TableFinder table_finder;
415 table_finder.Init(gridsize(), bleft(), tright());
416 table_finder.set_resolution(resolution_);
417 table_finder.set_left_to_right_language(!input_block->block->right_to_left());
418 // Copy cleaned partitions from part_grid_ to clean_part_grid_ and
419 // insert dot-like noise into period_grid_
420 table_finder.InsertCleanPartitions(&part_grid_, input_block);
421 // Get Table Regions
422 table_finder.LocateTables(&part_grid_, best_columns_, WidthCB(), reskew_);
423 }
424 GridRemoveUnderlinePartitions();
425 part_grid_.DeleteUnknownParts(input_block);
426
427 // Build the partitions into chains that belong in the same block and
428 // refine into one-to-one links, then smooth the types within each chain.
429 part_grid_.FindPartitionPartners();
430 part_grid_.FindFigureCaptions();
431 part_grid_.RefinePartitionPartners(true);
432 SmoothPartnerRuns();
433
434 #ifndef GRAPHICS_DISABLED
435 if (textord_tabfind_show_partitions) {
436 ScrollView *window = MakeWindow(400, 300, "Partitions");
437 if (window != nullptr) {
438 part_grid_.DisplayBoxes(window);
439 if (!textord_debug_printable) {
440 DisplayTabVectors(window);
441 }
442 if (window != nullptr && textord_tabfind_show_partitions > 1) {
443 window->AwaitEvent(SVET_DESTROY);
444 }
445 }
446 }
447 #endif // !GRAPHICS_DISABLED
448 part_grid_.AssertNoDuplicates();
449 }
450 // Ownership of the ColPartitions moves from part_sets_ to part_grid_ here,
451 // and ownership of the BLOBNBOXes moves to the ColPartitions.
452 // (They were previously owned by the block or the image_bblobs list.)
453 ReleaseBlobsAndCleanupUnused(input_block);
454 // Ownership of the ColPartitions moves from part_grid_ to good_parts_ and
455 // noise_parts_ here. In text blocks, ownership of the BLOBNBOXes moves
456 // from the ColPartitions to the output TO_BLOCK. In non-text, the
457 // BLOBNBOXes stay with the ColPartitions and get deleted in the destructor.
458 if (PSM_SPARSE(pageseg_mode)) {
459 part_grid_.ExtractPartitionsAsBlocks(blocks, to_blocks);
460 } else {
461 TransformToBlocks(blocks, to_blocks);
462 }
463 if (textord_debug_tabfind) {
464 tprintf("Found %d blocks, %d to_blocks\n", blocks->length(), to_blocks->length());
465 }
466
467 #ifndef GRAPHICS_DISABLED
468 if (textord_tabfind_show_blocks) {
469 DisplayBlocks(blocks);
470 }
471 #endif
472 RotateAndReskewBlocks(input_is_rtl, to_blocks);
473 int result = 0;
474 #ifndef GRAPHICS_DISABLED
475 if (blocks_win_ != nullptr) {
476 bool waiting = false;
477 do {
478 waiting = false;
479 auto event = blocks_win_->AwaitEvent(SVET_ANY);
480 if (event->type == SVET_INPUT && event->parameter != nullptr) {
481 if (*event->parameter == 'd') {
482 result = -1;
483 } else {
484 blocks->clear();
485 }
486 } else if (event->type == SVET_DESTROY) {
487 blocks_win_ = nullptr;
488 } else {
489 waiting = true;
490 }
491 } while (waiting);
492 }
493 #endif // !GRAPHICS_DISABLED
494 return result;
495 }
496
497 // Get the rotation required to deskew, and its inverse rotation.
498 void ColumnFinder::GetDeskewVectors(FCOORD *deskew, FCOORD *reskew) {
499 *reskew = reskew_;
500 *deskew = reskew_;
501 deskew->set_y(-deskew->y());
502 }
503
504 #ifndef DISABLED_LEGACY_ENGINE
505 void ColumnFinder::SetEquationDetect(EquationDetectBase *detect) {
506 equation_detect_ = detect;
507 }
508 #endif
509
510 //////////////// PRIVATE CODE /////////////////////////
511
512 #ifndef GRAPHICS_DISABLED
513
514 // Displays the blob and block bounding boxes in a window called Blocks.
515 void ColumnFinder::DisplayBlocks(BLOCK_LIST *blocks) {
516 if (blocks_win_ == nullptr) {
517 blocks_win_ = MakeWindow(700, 300, "Blocks");
518 } else {
519 blocks_win_->Clear();
520 }
521 DisplayBoxes(blocks_win_);
522 BLOCK_IT block_it(blocks);
523 int serial = 1;
524 for (block_it.mark_cycle_pt(); !block_it.cycled_list(); block_it.forward()) {
525 BLOCK *block = block_it.data();
526 block->pdblk.plot(blocks_win_, serial++,
527 textord_debug_printable ? ScrollView::BLUE : ScrollView::GREEN);
528 }
529 blocks_win_->Update();
530 }
531
532 // Displays the column edges at each grid y coordinate defined by
533 // best_columns_.
534 void ColumnFinder::DisplayColumnBounds(PartSetVector *sets) {
535 ScrollView *col_win = MakeWindow(50, 300, "Columns");
536 DisplayBoxes(col_win);
537 col_win->Pen(textord_debug_printable ? ScrollView::BLUE : ScrollView::GREEN);
538 for (int i = 0; i < gridheight_; ++i) {
539 ColPartitionSet *columns = best_columns_[i];
540 if (columns != nullptr) {
541 columns->DisplayColumnEdges(i * gridsize_, (i + 1) * gridsize_, col_win);
542 }
543 }
544 }
545
546 #endif // !GRAPHICS_DISABLED
547
548 // Sets up column_sets_ (the determined column layout at each horizontal
549 // slice). Returns false if the page is empty.
550 bool ColumnFinder::MakeColumns(bool single_column) {
551 // The part_sets_ are a temporary structure used during column creation,
552 // and is a vector of ColPartitionSets, representing ColPartitions found
553 // at horizontal slices through the page.
554 PartSetVector part_sets;
555 if (!single_column) {
556 if (!part_grid_.MakeColPartSets(&part_sets)) {
557 return false; // Empty page.
558 }
559 ASSERT_HOST(part_grid_.gridheight() == gridheight_);
560 // Try using only the good parts first.
561 bool good_only = true;
562 do {
563 for (int i = 0; i < gridheight_; ++i) {
564 ColPartitionSet *line_set = part_sets.at(i);
565 if (line_set != nullptr && line_set->LegalColumnCandidate()) {
566 ColPartitionSet *column_candidate = line_set->Copy(good_only);
567 if (column_candidate != nullptr) {
568 column_candidate->AddToColumnSetsIfUnique(&column_sets_, WidthCB());
569 }
570 }
571 }
572 good_only = !good_only;
573 } while (column_sets_.empty() && !good_only);
574 if (textord_debug_tabfind) {
575 PrintColumnCandidates("Column candidates");
576 }
577 // Improve the column candidates against themselves.
578 ImproveColumnCandidates(&column_sets_, &column_sets_);
579 if (textord_debug_tabfind) {
580 PrintColumnCandidates("Improved columns");
581 }
582 // Improve the column candidates using the part_sets_.
583 ImproveColumnCandidates(&part_sets, &column_sets_);
584 }
585 ColPartitionSet *single_column_set = part_grid_.MakeSingleColumnSet(WidthCB());
586 if (single_column_set != nullptr) {
587 // Always add the single column set as a backup even if not in
588 // single column mode.
589 single_column_set->AddToColumnSetsIfUnique(&column_sets_, WidthCB());
590 }
591 if (textord_debug_tabfind) {
592 PrintColumnCandidates("Final Columns");
593 }
594 bool has_columns = !column_sets_.empty();
595 if (has_columns) {
596 // Divide the page into sections of uniform column layout.
597 bool any_multi_column = AssignColumns(part_sets);
598 #ifndef GRAPHICS_DISABLED
599 if (textord_tabfind_show_columns) {
600 DisplayColumnBounds(&part_sets);
601 }
602 #endif
603 ComputeMeanColumnGap(any_multi_column);
604 }
605 for (auto line_set : part_sets) {
606 if (line_set != nullptr) {
607 line_set->RelinquishParts();
608 delete line_set;
609 }
610 }
611 return has_columns;
612 }
613
614 // Attempt to improve the column_candidates by expanding the columns
615 // and adding new partitions from the partition sets in src_sets.
616 // Src_sets may be equal to column_candidates, in which case it will
617 // use them as a source to improve themselves.
618 void ColumnFinder::ImproveColumnCandidates(PartSetVector *src_sets, PartSetVector *column_sets) {
619 // TODO: optimize.
620 PartSetVector temp_cols = *column_sets;
621 column_sets->clear();
622 if (src_sets == column_sets) {
623 src_sets = &temp_cols;
624 }
625 int set_size = temp_cols.size();
626 // Try using only the good parts first.
627 bool good_only = true;
628 do {
629 for (int i = 0; i < set_size; ++i) {
630 ColPartitionSet *column_candidate = temp_cols.at(i);
631 ASSERT_HOST(column_candidate != nullptr);
632 ColPartitionSet *improved = column_candidate->Copy(good_only);
633 if (improved != nullptr) {
634 improved->ImproveColumnCandidate(WidthCB(), src_sets);
635 improved->AddToColumnSetsIfUnique(column_sets, WidthCB());
636 }
637 }
638 good_only = !good_only;
639 } while (column_sets->empty() && !good_only);
640 if (column_sets->empty()) {
641 // TODO: optimize.
642 *column_sets = temp_cols;
643 temp_cols.clear();
644 } else {
645 for (auto data : temp_cols) {
646 delete data;
647 }
648 }
649 }
650
651 // Prints debug information on the column candidates.
652 void ColumnFinder::PrintColumnCandidates(const char *title) {
653 int set_size = column_sets_.size();
654 tprintf("Found %d %s:\n", set_size, title);
655 if (textord_debug_tabfind >= 3) {
656 for (int i = 0; i < set_size; ++i) {
657 ColPartitionSet *column_set = column_sets_.at(i);
658 column_set->Print();
659 }
660 }
661 }
662
663 // Finds the optimal set of columns that cover the entire image with as
664 // few changes in column partition as possible.
665 // NOTE: this could be thought of as an optimization problem, but a simple
666 // greedy algorithm is used instead. The algorithm repeatedly finds the modal
667 // compatible column in an unassigned region and uses that with the extra
668 // tweak of extending the modal region over small breaks in compatibility.
669 // Where modal regions overlap, the boundary is chosen so as to minimize
670 // the cost in terms of ColPartitions not fitting an approved column.
671 // Returns true if any part of the page is multi-column.
672 bool ColumnFinder::AssignColumns(const PartSetVector &part_sets) {
673 int set_count = part_sets.size();
674 ASSERT_HOST(set_count == gridheight());
675 // Allocate and init the best_columns_.
676 best_columns_ = new ColPartitionSet *[set_count];
677 for (int y = 0; y < set_count; ++y) {
678 best_columns_[y] = nullptr;
679 }
680 int column_count = column_sets_.size();
681 // column_set_costs[part_sets_ index][column_sets_ index] is
682 // < INT32_MAX if the partition set is compatible with the column set,
683 // in which case its value is the cost for that set used in deciding
684 // which competing set to assign.
685 // any_columns_possible[part_sets_ index] is true if any of
686 // possible_column_sets[part_sets_ index][*] is < INT32_MAX.
687 // assigned_costs[part_sets_ index] is set to the column_set_costs
688 // of the assigned column_sets_ index or INT32_MAX if none is set.
689 // On return the best_columns_ member is set.
690 bool *any_columns_possible = new bool[set_count];
691 int *assigned_costs = new int[set_count];
692 int **column_set_costs = new int *[set_count];
693 // Set possible column_sets to indicate whether each set is compatible
694 // with each column.
695 for (int part_i = 0; part_i < set_count; ++part_i) {
696 ColPartitionSet *line_set = part_sets.at(part_i);
697 bool debug = line_set != nullptr && WithinTestRegion(2, line_set->bounding_box().left(),
698 line_set->bounding_box().bottom());
699 column_set_costs[part_i] = new int[column_count];
700 any_columns_possible[part_i] = false;
701 assigned_costs[part_i] = INT32_MAX;
702 for (int col_i = 0; col_i < column_count; ++col_i) {
703 if (line_set != nullptr &&
704 column_sets_.at(col_i)->CompatibleColumns(debug, line_set, WidthCB())) {
705 column_set_costs[part_i][col_i] = column_sets_.at(col_i)->UnmatchedWidth(line_set);
706 any_columns_possible[part_i] = true;
707 } else {
708 column_set_costs[part_i][col_i] = INT32_MAX;
709 if (debug) {
710 tprintf("Set id %d did not match at y=%d, lineset =%p\n",
711 col_i, part_i, static_cast<void *>(line_set));
712 }
713 }
714 }
715 }
716 bool any_multi_column = false;
717 // Assign a column set to each vertical grid position.
718 // While there is an unassigned range, find its mode.
719 int start, end;
720 while (BiggestUnassignedRange(set_count, any_columns_possible, &start, &end)) {
721 if (textord_debug_tabfind >= 2) {
722 tprintf("Biggest unassigned range = %d- %d\n", start, end);
723 }
724 // Find the modal column_set_id in the range.
725 int column_set_id = RangeModalColumnSet(column_set_costs, assigned_costs, start, end);
726 if (textord_debug_tabfind >= 2) {
727 tprintf("Range modal column id = %d\n", column_set_id);
728 column_sets_.at(column_set_id)->Print();
729 }
730 // Now find the longest run of the column_set_id in the range.
731 ShrinkRangeToLongestRun(column_set_costs, assigned_costs, any_columns_possible, column_set_id,
732 &start, &end);
733 if (textord_debug_tabfind >= 2) {
734 tprintf("Shrunk range = %d- %d\n", start, end);
735 }
736 // Extend the start and end past the longest run, while there are
737 // only small gaps in compatibility that can be overcome by larger
738 // regions of compatibility beyond.
739 ExtendRangePastSmallGaps(column_set_costs, assigned_costs, any_columns_possible, column_set_id,
740 -1, -1, &start);
741 --end;
742 ExtendRangePastSmallGaps(column_set_costs, assigned_costs, any_columns_possible, column_set_id,
743 1, set_count, &end);
744 ++end;
745 if (textord_debug_tabfind) {
746 tprintf("Column id %d applies to range = %d - %d\n", column_set_id, start, end);
747 }
748 // Assign the column to the range, which now may overlap with other ranges.
749 AssignColumnToRange(column_set_id, start, end, column_set_costs, assigned_costs);
750 if (column_sets_.at(column_set_id)->GoodColumnCount() > 1) {
751 any_multi_column = true;
752 }
753 }
754 // If anything remains unassigned, the whole lot is unassigned, so
755 // arbitrarily assign id 0.
756 if (best_columns_[0] == nullptr) {
757 AssignColumnToRange(0, 0, gridheight_, column_set_costs, assigned_costs);
758 }
759 // Free memory.
760 for (int i = 0; i < set_count; ++i) {
761 delete[] column_set_costs[i];
762 }
763 delete[] assigned_costs;
764 delete[] any_columns_possible;
765 delete[] column_set_costs;
766 return any_multi_column;
767 }
768
769 // Finds the biggest range in part_sets_ that has no assigned column, but
770 // column assignment is possible.
771 bool ColumnFinder::BiggestUnassignedRange(int set_count, const bool *any_columns_possible,
772 int *best_start, int *best_end) {
773 int best_range_size = 0;
774 *best_start = set_count;
775 *best_end = set_count;
776 int end = set_count;
777 for (int start = 0; start < gridheight_; start = end) {
778 // Find the first unassigned index in start.
779 while (start < set_count) {
780 if (best_columns_[start] == nullptr && any_columns_possible[start]) {
781 break;
782 }
783 ++start;
784 }
785 // Find the first past the end and count the good ones in between.
786 int range_size = 1; // Number of non-null, but unassigned line sets.
787 end = start + 1;
788 while (end < set_count) {
789 if (best_columns_[end] != nullptr) {
790 break;
791 }
792 if (any_columns_possible[end]) {
793 ++range_size;
794 }
795 ++end;
796 }
797 if (start < set_count && range_size > best_range_size) {
798 best_range_size = range_size;
799 *best_start = start;
800 *best_end = end;
801 }
802 }
803 return *best_start < *best_end;
804 }
805
806 // Finds the modal compatible column_set_ index within the given range.
807 int ColumnFinder::RangeModalColumnSet(int **column_set_costs, const int *assigned_costs, int start,
808 int end) {
809 int column_count = column_sets_.size();
810 STATS column_stats(0, column_count - 1);
811 for (int part_i = start; part_i < end; ++part_i) {
812 for (int col_j = 0; col_j < column_count; ++col_j) {
813 if (column_set_costs[part_i][col_j] < assigned_costs[part_i]) {
814 column_stats.add(col_j, 1);
815 }
816 }
817 }
818 ASSERT_HOST(column_stats.get_total() > 0);
819 return column_stats.mode();
820 }
821
822 // Given that there are many column_set_id compatible columns in the range,
823 // shrinks the range to the longest contiguous run of compatibility, allowing
824 // gaps where no columns are possible, but not where competing columns are
825 // possible.
826 void ColumnFinder::ShrinkRangeToLongestRun(int **column_set_costs, const int *assigned_costs,
827 const bool *any_columns_possible, int column_set_id,
828 int *best_start, int *best_end) {
829 // orig_start and orig_end are the maximum range we will look at.
830 int orig_start = *best_start;
831 int orig_end = *best_end;
832 int best_range_size = 0;
833 *best_start = orig_end;
834 *best_end = orig_end;
835 int end = orig_end;
836 for (int start = orig_start; start < orig_end; start = end) {
837 // Find the first possible
838 while (start < orig_end) {
839 if (column_set_costs[start][column_set_id] < assigned_costs[start] ||
840 !any_columns_possible[start]) {
841 break;
842 }
843 ++start;
844 }
845 // Find the first past the end.
846 end = start + 1;
847 while (end < orig_end) {
848 if (column_set_costs[end][column_set_id] >= assigned_costs[start] &&
849 any_columns_possible[end]) {
850 break;
851 }
852 ++end;
853 }
854 if (start < orig_end && end - start > best_range_size) {
855 best_range_size = end - start;
856 *best_start = start;
857 *best_end = end;
858 }
859 }
860 }
861
862 // Moves start in the direction of step, up to, but not including end while
863 // the only incompatible regions are no more than kMaxIncompatibleColumnCount
864 // in size, and the compatible regions beyond are bigger.
865 void ColumnFinder::ExtendRangePastSmallGaps(int **column_set_costs, const int *assigned_costs,
866 const bool *any_columns_possible, int column_set_id,
867 int step, int end, int *start) {
868 if (textord_debug_tabfind > 2) {
869 tprintf("Starting expansion at %d, step=%d, limit=%d\n", *start, step, end);
870 }
871 if (*start == end) {
872 return; // Cannot be expanded.
873 }
874
875 int barrier_size = 0;
876 int good_size = 0;
877 do {
878 // Find the size of the incompatible barrier.
879 barrier_size = 0;
880 int i;
881 for (i = *start + step; i != end; i += step) {
882 if (column_set_costs[i][column_set_id] < assigned_costs[i]) {
883 break; // We are back on.
884 }
885 // Locations where none are possible don't count.
886 if (any_columns_possible[i]) {
887 ++barrier_size;
888 }
889 }
890 if (textord_debug_tabfind > 2) {
891 tprintf("At %d, Barrier size=%d\n", i, barrier_size);
892 }
893 if (barrier_size > kMaxIncompatibleColumnCount) {
894 return; // Barrier too big.
895 }
896 if (i == end) {
897 // We can't go any further, but the barrier was small, so go to the end.
898 *start = i - step;
899 return;
900 }
901 // Now find the size of the good region on the other side.
902 good_size = 1;
903 for (i += step; i != end; i += step) {
904 if (column_set_costs[i][column_set_id] < assigned_costs[i]) {
905 ++good_size;
906 } else if (any_columns_possible[i]) {
907 break;
908 }
909 }
910 if (textord_debug_tabfind > 2) {
911 tprintf("At %d, good size = %d\n", i, good_size);
912 }
913 // If we had enough good ones we can extend the start and keep looking.
914 if (good_size >= barrier_size) {
915 *start = i - step;
916 }
917 } while (good_size >= barrier_size);
918 }
919
920 // Assigns the given column_set_id to the given range.
921 void ColumnFinder::AssignColumnToRange(int column_set_id, int start, int end,
922 int **column_set_costs, int *assigned_costs) {
923 ColPartitionSet *column_set = column_sets_.at(column_set_id);
924 for (int i = start; i < end; ++i) {
925 assigned_costs[i] = column_set_costs[i][column_set_id];
926 best_columns_[i] = column_set;
927 }
928 }
929
930 // Computes the mean_column_gap_.
931 void ColumnFinder::ComputeMeanColumnGap(bool any_multi_column) {
932 int total_gap = 0;
933 int total_width = 0;
934 int gap_samples = 0;
935 int width_samples = 0;
936 for (int i = 0; i < gridheight_; ++i) {
937 ASSERT_HOST(best_columns_[i] != nullptr);
938 best_columns_[i]->AccumulateColumnWidthsAndGaps(&total_width, &width_samples, &total_gap,
939 &gap_samples);
940 }
941 mean_column_gap_ = any_multi_column && gap_samples > 0
942 ? total_gap / gap_samples
943 : width_samples > 0 ? total_width / width_samples : 0;
944 }
945
946 //////// Functions that manipulate ColPartitions in the part_grid_ /////
947 //////// to split, merge, find margins, and find types. //////////////
948
949 // Helper to delete all the deletable blobs on the list. Owned blobs are
950 // extracted from the list, but not deleted, leaving them owned by the owner().
951 static void ReleaseAllBlobsAndDeleteUnused(BLOBNBOX_LIST *blobs) {
952 for (BLOBNBOX_IT blob_it(blobs); !blob_it.empty(); blob_it.forward()) {
953 BLOBNBOX *blob = blob_it.extract();
954 if (blob->owner() == nullptr) {
955 delete blob;
956 }
957 }
958 }
959
960 // Hoovers up all un-owned blobs and deletes them.
961 // The rest get released from the block so the ColPartitions can pass
962 // ownership to the output blocks.
963 void ColumnFinder::ReleaseBlobsAndCleanupUnused(TO_BLOCK *block) {
964 ReleaseAllBlobsAndDeleteUnused(&block->blobs);
965 ReleaseAllBlobsAndDeleteUnused(&block->small_blobs);
966 ReleaseAllBlobsAndDeleteUnused(&block->noise_blobs);
967 ReleaseAllBlobsAndDeleteUnused(&block->large_blobs);
968 ReleaseAllBlobsAndDeleteUnused(&image_bblobs_);
969 }
970
971 // Splits partitions that cross columns where they have nothing in the gap.
972 void ColumnFinder::GridSplitPartitions() {
973 // Iterate the ColPartitions in the grid.
974 ColPartitionGridSearch gsearch(&part_grid_);
975 gsearch.StartFullSearch();
976 ColPartition *dont_repeat = nullptr;
977 ColPartition *part;
978 while ((part = gsearch.NextFullSearch()) != nullptr) {
979 if (part->blob_type() < BRT_UNKNOWN || part == dont_repeat) {
980 continue; // Only applies to text partitions.
981 }
982 ColPartitionSet *column_set = best_columns_[gsearch.GridY()];
983 int first_col = -1;
984 int last_col = -1;
985 // Find which columns the partition spans.
986 part->ColumnRange(resolution_, column_set, &first_col, &last_col);
987 if (first_col > 0) {
988 --first_col;
989 }
990 // Convert output column indices to physical column indices.
991 first_col /= 2;
992 last_col /= 2;
993 // We will only consider cases where a partition spans two columns,
994 // since a heading that spans more columns than that is most likely
995 // genuine.
996 if (last_col != first_col + 1) {
997 continue;
998 }
999 // Set up a rectangle search x-bounded by the column gap and y by the part.
1000 int y = part->MidY();
1001 TBOX margin_box = part->bounding_box();
1002 bool debug = AlignedBlob::WithinTestRegion(2, margin_box.left(), margin_box.bottom());
1003 if (debug) {
1004 tprintf("Considering partition for GridSplit:");
1005 part->Print();
1006 }
1007 ColPartition *column = column_set->GetColumnByIndex(first_col);
1008 if (column == nullptr) {
1009 continue;
1010 }
1011 margin_box.set_left(column->RightAtY(y) + 2);
1012 column = column_set->GetColumnByIndex(last_col);
1013 if (column == nullptr) {
1014 continue;
1015 }
1016 margin_box.set_right(column->LeftAtY(y) - 2);
1017 // TODO(rays) Decide whether to keep rectangular filling or not in the
1018 // main grid and therefore whether we need a fancier search here.
1019 // Now run the rect search on the main blob grid.
1020 GridSearch<BLOBNBOX, BLOBNBOX_CLIST, BLOBNBOX_C_IT> rectsearch(this);
1021 if (debug) {
1022 tprintf("Searching box (%d,%d)->(%d,%d)\n", margin_box.left(), margin_box.bottom(),
1023 margin_box.right(), margin_box.top());
1024 part->Print();
1025 }
1026 rectsearch.StartRectSearch(margin_box);
1027 BLOBNBOX *bbox;
1028 while ((bbox = rectsearch.NextRectSearch()) != nullptr) {
1029 if (bbox->bounding_box().overlap(margin_box)) {
1030 break;
1031 }
1032 }
1033 if (bbox == nullptr) {
1034 // There seems to be nothing in the hole, so split the partition.
1035 gsearch.RemoveBBox();
1036 int x_middle = (margin_box.left() + margin_box.right()) / 2;
1037 if (debug) {
1038 tprintf("Splitting part at %d:", x_middle);
1039 part->Print();
1040 }
1041 ColPartition *split_part = part->SplitAt(x_middle);
1042 if (split_part != nullptr) {
1043 if (debug) {
1044 tprintf("Split result:");
1045 part->Print();
1046 split_part->Print();
1047 }
1048 part_grid_.InsertBBox(true, true, split_part);
1049 } else {
1050 // Split had no effect
1051 if (debug) {
1052 tprintf("Split had no effect\n");
1053 }
1054 dont_repeat = part;
1055 }
1056 part_grid_.InsertBBox(true, true, part);
1057 gsearch.RepositionIterator();
1058 } else if (debug) {
1059 tprintf("Part cannot be split: blob (%d,%d)->(%d,%d) in column gap\n",
1060 bbox->bounding_box().left(), bbox->bounding_box().bottom(),
1061 bbox->bounding_box().right(), bbox->bounding_box().top());
1062 }
1063 }
1064 }
1065
1066 // Merges partitions where there is vertical overlap, within a single column,
1067 // and the horizontal gap is small enough.
1068 void ColumnFinder::GridMergePartitions() {
1069 // Iterate the ColPartitions in the grid.
1070 GridSearch<ColPartition, ColPartition_CLIST, ColPartition_C_IT> gsearch(&part_grid_);
1071 gsearch.StartFullSearch();
1072 ColPartition *part;
1073 while ((part = gsearch.NextFullSearch()) != nullptr) {
1074 if (part->IsUnMergeableType()) {
1075 continue;
1076 }
1077 // Set up a rectangle search x-bounded by the column and y by the part.
1078 ColPartitionSet *columns = best_columns_[gsearch.GridY()];
1079 TBOX box = part->bounding_box();
1080 bool debug = AlignedBlob::WithinTestRegion(1, box.left(), box.bottom());
1081 if (debug) {
1082 tprintf("Considering part for merge at:");
1083 part->Print();
1084 }
1085 int y = part->MidY();
1086 ColPartition *left_column = columns->ColumnContaining(box.left(), y);
1087 ColPartition *right_column = columns->ColumnContaining(box.right(), y);
1088 if (left_column == nullptr || right_column != left_column) {
1089 if (debug) {
1090 tprintf("In different columns\n");
1091 }
1092 continue;
1093 }
1094 box.set_left(left_column->LeftAtY(y));
1095 box.set_right(right_column->RightAtY(y));
1096 // Now run the rect search.
1097 bool modified_box = false;
1098 GridSearch<ColPartition, ColPartition_CLIST, ColPartition_C_IT> rsearch(&part_grid_);
1099 rsearch.SetUniqueMode(true);
1100 rsearch.StartRectSearch(box);
1101 ColPartition *neighbour;
1102
1103 while ((neighbour = rsearch.NextRectSearch()) != nullptr) {
1104 if (neighbour == part || neighbour->IsUnMergeableType()) {
1105 continue;
1106 }
1107 const TBOX &neighbour_box = neighbour->bounding_box();
1108 if (debug) {
1109 tprintf("Considering merge with neighbour at:");
1110 neighbour->Print();
1111 }
1112 if (neighbour_box.right() < box.left() || neighbour_box.left() > box.right()) {
1113 continue; // Not within the same column.
1114 }
1115 if (part->VSignificantCoreOverlap(*neighbour) && part->TypesMatch(*neighbour)) {
1116 // There is vertical overlap and the gross types match, but only
1117 // merge if the horizontal gap is small enough, as one of the
1118 // partitions may be a figure caption within a column.
1119 // If there is only one column, then the mean_column_gap_ is large
1120 // enough to allow almost any merge, by being the mean column width.
1121 const TBOX &part_box = part->bounding_box();
1122 // Don't merge if there is something else in the way. Use the margin
1123 // to decide, and check both to allow a bit of overlap.
1124 if (neighbour_box.left() > part->right_margin() &&
1125 part_box.right() < neighbour->left_margin()) {
1126 continue; // Neighbour is too far to the right.
1127 }
1128 if (neighbour_box.right() < part->left_margin() &&
1129 part_box.left() > neighbour->right_margin()) {
1130 continue; // Neighbour is too far to the left.
1131 }
1132 int h_gap = std::max(part_box.left(), neighbour_box.left()) -
1133 std::min(part_box.right(), neighbour_box.right());
1134 if (h_gap < mean_column_gap_ * kHorizontalGapMergeFraction ||
1135 part_box.width() < mean_column_gap_ || neighbour_box.width() < mean_column_gap_) {
1136 if (debug) {
1137 tprintf("Running grid-based merge between:\n");
1138 part->Print();
1139 neighbour->Print();
1140 }
1141 rsearch.RemoveBBox();
1142 if (!modified_box) {
1143 // We are going to modify part, so remove it and re-insert it after.
1144 gsearch.RemoveBBox();
1145 rsearch.RepositionIterator();
1146 modified_box = true;
1147 }
1148 part->Absorb(neighbour, WidthCB());
1149 } else if (debug) {
1150 tprintf("Neighbour failed hgap test\n");
1151 }
1152 } else if (debug) {
1153 tprintf("Neighbour failed overlap or typesmatch test\n");
1154 }
1155 }
1156 if (modified_box) {
1157 // We modified the box of part, so re-insert it into the grid.
1158 // This does no harm in the current cell, as it already exists there,
1159 // but it needs to exist in all the cells covered by its bounding box,
1160 // or it will never be found by a full search.
1161 // Because the box has changed, it has to be removed first, otherwise
1162 // add_sorted may fail to keep a single copy of the pointer.
1163 part_grid_.InsertBBox(true, true, part);
1164 gsearch.RepositionIterator();
1165 }
1166 }
1167 }
1168
1169 // Inserts remaining noise blobs into the most applicable partition if any.
1170 // If there is no applicable partition, then the blobs are deleted.
1171 void ColumnFinder::InsertRemainingNoise(TO_BLOCK *block) {
1172 BLOBNBOX_IT blob_it(&block->noise_blobs);
1173 for (blob_it.mark_cycle_pt(); !blob_it.cycled_list(); blob_it.forward()) {
1174 BLOBNBOX *blob = blob_it.data();
1175 if (blob->owner() != nullptr) {
1176 continue;
1177 }
1178 TBOX search_box(blob->bounding_box());
1179 bool debug = WithinTestRegion(2, search_box.left(), search_box.bottom());
1180 search_box.pad(gridsize(), gridsize());
1181 // Setup a rectangle search to find the best partition to merge with.
1182 ColPartitionGridSearch rsearch(&part_grid_);
1183 rsearch.SetUniqueMode(true);
1184 rsearch.StartRectSearch(search_box);
1185 ColPartition *part;
1186 ColPartition *best_part = nullptr;
1187 int best_distance = 0;
1188 while ((part = rsearch.NextRectSearch()) != nullptr) {
1189 if (part->IsUnMergeableType()) {
1190 continue;
1191 }
1192 int distance =
1193 projection_.DistanceOfBoxFromPartition(blob->bounding_box(), *part, denorm_, debug);
1194 if (best_part == nullptr || distance < best_distance) {
1195 best_part = part;
1196 best_distance = distance;
1197 }
1198 }
1199 if (best_part != nullptr &&
1200 best_distance < kMaxDistToPartSizeRatio * best_part->median_height()) {
1201 // Close enough to merge.
1202 if (debug) {
1203 tprintf("Adding noise blob with distance %d, thr=%g:box:", best_distance,
1204 kMaxDistToPartSizeRatio * best_part->median_height());
1205 blob->bounding_box().print();
1206 tprintf("To partition:");
1207 best_part->Print();
1208 }
1209 part_grid_.RemoveBBox(best_part);
1210 best_part->AddBox(blob);
1211 part_grid_.InsertBBox(true, true, best_part);
1212 blob->set_owner(best_part);
1213 blob->set_flow(best_part->flow());
1214 blob->set_region_type(best_part->blob_type());
1215 } else {
1216 // Mark the blob for deletion.
1217 blob->set_region_type(BRT_NOISE);
1218 }
1219 }
1220 // Delete the marked blobs, clearing neighbour references.
1221 block->DeleteUnownedNoise();
1222 }
1223
1224 // Helper makes a box from a horizontal line.
1225 static TBOX BoxFromHLine(const TabVector *hline) {
1226 int top = std::max(hline->startpt().y(), hline->endpt().y());
1227 int bottom = std::min(hline->startpt().y(), hline->endpt().y());
1228 top += hline->mean_width();
1229 if (top == bottom) {
1230 if (bottom > 0) {
1231 --bottom;
1232 } else {
1233 ++top;
1234 }
1235 }
1236 return TBOX(hline->startpt().x(), bottom, hline->endpt().x(), top);
1237 }
1238
1239 // Remove partitions that come from horizontal lines that look like
1240 // underlines, but are not part of a table.
1241 void ColumnFinder::GridRemoveUnderlinePartitions() {
1242 TabVector_IT hline_it(&horizontal_lines_);
1243 for (hline_it.mark_cycle_pt(); !hline_it.cycled_list(); hline_it.forward()) {
1244 TabVector *hline = hline_it.data();
1245 if (hline->intersects_other_lines()) {
1246 continue;
1247 }
1248 TBOX line_box = BoxFromHLine(hline);
1249 TBOX search_box = line_box;
1250 search_box.pad(0, line_box.height());
1251 ColPartitionGridSearch part_search(&part_grid_);
1252 part_search.SetUniqueMode(true);
1253 part_search.StartRectSearch(search_box);
1254 ColPartition *covered;
1255 bool touched_table = false;
1256 bool touched_text = false;
1257 ColPartition *line_part = nullptr;
1258 while ((covered = part_search.NextRectSearch()) != nullptr) {
1259 if (covered->type() == PT_TABLE) {
1260 touched_table = true;
1261 break;
1262 } else if (covered->IsTextType()) {
1263 // TODO(rays) Add a list of underline sections to ColPartition.
1264 int text_bottom = covered->median_bottom();
1265 if (line_box.bottom() <= text_bottom && text_bottom <= search_box.top()) {
1266 touched_text = true;
1267 }
1268 } else if (covered->blob_type() == BRT_HLINE && line_box.contains(covered->bounding_box()) &&
1269 // not if same instance (identical to hline)
1270 !TBOX(covered->bounding_box()).contains(line_box)) {
1271 line_part = covered;
1272 }
1273 }
1274 if (line_part != nullptr && !touched_table && touched_text) {
1275 part_grid_.RemoveBBox(line_part);
1276 delete line_part;
1277 }
1278 }
1279 }
1280
1281 // Add horizontal line separators as partitions.
1282 void ColumnFinder::GridInsertHLinePartitions() {
1283 TabVector_IT hline_it(&horizontal_lines_);
1284 for (hline_it.mark_cycle_pt(); !hline_it.cycled_list(); hline_it.forward()) {
1285 TabVector *hline = hline_it.data();
1286 TBOX line_box = BoxFromHLine(hline);
1287 ColPartition *part =
1288 ColPartition::MakeLinePartition(BRT_HLINE, vertical_skew_, line_box.left(),
1289 line_box.bottom(), line_box.right(), line_box.top());
1290 part->set_type(PT_HORZ_LINE);
1291 bool any_image = false;
1292 ColPartitionGridSearch part_search(&part_grid_);
1293 part_search.SetUniqueMode(true);
1294 part_search.StartRectSearch(line_box);
1295 ColPartition *covered;
1296 while ((covered = part_search.NextRectSearch()) != nullptr) {
1297 if (covered->IsImageType()) {
1298 any_image = true;
1299 break;
1300 }
1301 }
1302 if (!any_image) {
1303 part_grid_.InsertBBox(true, true, part);
1304 } else {
1305 delete part;
1306 }
1307 }
1308 }
1309
1310 // Add horizontal line separators as partitions.
1311 void ColumnFinder::GridInsertVLinePartitions() {
1312 TabVector_IT vline_it(dead_vectors());
1313 for (vline_it.mark_cycle_pt(); !vline_it.cycled_list(); vline_it.forward()) {
1314 TabVector *vline = vline_it.data();
1315 if (!vline->IsSeparator()) {
1316 continue;
1317 }
1318 int left = std::min(vline->startpt().x(), vline->endpt().x());
1319 int right = std::max(vline->startpt().x(), vline->endpt().x());
1320 right += vline->mean_width();
1321 if (left == right) {
1322 if (left > 0) {
1323 --left;
1324 } else {
1325 ++right;
1326 }
1327 }
1328 ColPartition *part = ColPartition::MakeLinePartition(
1329 BRT_VLINE, vertical_skew_, left, vline->startpt().y(), right, vline->endpt().y());
1330 part->set_type(PT_VERT_LINE);
1331 bool any_image = false;
1332 ColPartitionGridSearch part_search(&part_grid_);
1333 part_search.SetUniqueMode(true);
1334 part_search.StartRectSearch(part->bounding_box());
1335 ColPartition *covered;
1336 while ((covered = part_search.NextRectSearch()) != nullptr) {
1337 if (covered->IsImageType()) {
1338 any_image = true;
1339 break;
1340 }
1341 }
1342 if (!any_image) {
1343 part_grid_.InsertBBox(true, true, part);
1344 } else {
1345 delete part;
1346 }
1347 }
1348 }
1349
1350 // For every ColPartition in the grid, sets its type based on position
1351 // in the columns.
1352 void ColumnFinder::SetPartitionTypes() {
1353 GridSearch<ColPartition, ColPartition_CLIST, ColPartition_C_IT> gsearch(&part_grid_);
1354 gsearch.StartFullSearch();
1355 ColPartition *part;
1356 while ((part = gsearch.NextFullSearch()) != nullptr) {
1357 part->SetPartitionType(resolution_, best_columns_[gsearch.GridY()]);
1358 }
1359 }
1360
1361 // Only images remain with multiple types in a run of partners.
1362 // Sets the type of all in the group to the maximum of the group.
1363 void ColumnFinder::SmoothPartnerRuns() {
1364 // Iterate the ColPartitions in the grid.
1365 GridSearch<ColPartition, ColPartition_CLIST, ColPartition_C_IT> gsearch(&part_grid_);
1366 gsearch.StartFullSearch();
1367 ColPartition *part;
1368 while ((part = gsearch.NextFullSearch()) != nullptr) {
1369 ColPartition *partner = part->SingletonPartner(true);
1370 if (partner != nullptr) {
1371 if (partner->SingletonPartner(false) != part) {
1372 tprintf("Ooops! Partition:(%d partners)", part->upper_partners()->length());
1373 part->Print();
1374 tprintf("has singleton partner:(%d partners", partner->lower_partners()->length());
1375 partner->Print();
1376 tprintf("but its singleton partner is:");
1377 if (partner->SingletonPartner(false) == nullptr) {
1378 tprintf("NULL\n");
1379 } else {
1380 partner->SingletonPartner(false)->Print();
1381 }
1382 }
1383 ASSERT_HOST(partner->SingletonPartner(false) == part);
1384 } else if (part->SingletonPartner(false) != nullptr) {
1385 ColPartitionSet *column_set = best_columns_[gsearch.GridY()];
1386 int column_count = column_set->ColumnCount();
1387 part->SmoothPartnerRun(column_count * 2 + 1);
1388 }
1389 }
1390 }
1391
1392 // Helper functions for TransformToBlocks.
1393 // Add the part to the temp list in the correct order.
1394 void ColumnFinder::AddToTempPartList(ColPartition *part, ColPartition_CLIST *temp_list) {
1395 int mid_y = part->MidY();
1396 ColPartition_C_IT it(temp_list);
1397 for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
1398 ColPartition *test_part = it.data();
1399 if (part->type() == PT_NOISE || test_part->type() == PT_NOISE) {
1400 continue; // Noise stays in sequence.
1401 }
1402 if (test_part == part->SingletonPartner(false)) {
1403 break; // Insert before its lower partner.
1404 }
1405 int neighbour_bottom = test_part->median_bottom();
1406 int neighbour_top = test_part->median_top();
1407 int neighbour_y = (neighbour_bottom + neighbour_top) / 2;
1408 if (neighbour_y < mid_y) {
1409 break; // part is above test_part so insert it.
1410 }
1411 if (!part->HOverlaps(*test_part) && !part->WithinSameMargins(*test_part)) {
1412 continue; // Incompatibles stay in order
1413 }
1414 }
1415 if (it.cycled_list()) {
1416 it.add_to_end(part);
1417 } else {
1418 it.add_before_stay_put(part);
1419 }
1420 }
1421
1422 // Add everything from the temp list to the work_set assuming correct order.
1423 void ColumnFinder::EmptyTempPartList(ColPartition_CLIST *temp_list, WorkingPartSet_LIST *work_set) {
1424 ColPartition_C_IT it(temp_list);
1425 while (!it.empty()) {
1426 it.extract()->AddToWorkingSet(bleft_, tright_, resolution_, &good_parts_, work_set);
1427 it.forward();
1428 }
1429 }
1430
1431 // Transform the grid of partitions to the output blocks.
1432 void ColumnFinder::TransformToBlocks(BLOCK_LIST *blocks, TO_BLOCK_LIST *to_blocks) {
1433 WorkingPartSet_LIST work_set;
1434 ColPartitionSet *column_set = nullptr;
1435 ColPartition_IT noise_it(&noise_parts_);
1436 // The temp_part_list holds a list of parts at the same grid y coord
1437 // so they can be added in the correct order. This prevents thin objects
1438 // like horizontal lines going before the text lines above them.
1439 ColPartition_CLIST temp_part_list;
1440 // Iterate the ColPartitions in the grid. It starts at the top
1441 ColPartitionGridSearch gsearch(&part_grid_);
1442 gsearch.StartFullSearch();
1443 int prev_grid_y = -1;
1444 ColPartition *part;
1445 while ((part = gsearch.NextFullSearch()) != nullptr) {
1446 int grid_y = gsearch.GridY();
1447 if (grid_y != prev_grid_y) {
1448 EmptyTempPartList(&temp_part_list, &work_set);
1449 prev_grid_y = grid_y;
1450 }
1451 if (best_columns_[grid_y] != column_set) {
1452 column_set = best_columns_[grid_y];
1453 // Every line should have a non-null best column.
1454 ASSERT_HOST(column_set != nullptr);
1455 column_set->ChangeWorkColumns(bleft_, tright_, resolution_, &good_parts_, &work_set);
1456 if (textord_debug_tabfind) {
1457 tprintf("Changed column groups at grid index %d, y=%d\n", gsearch.GridY(),
1458 gsearch.GridY() * gridsize());
1459 }
1460 }
1461 if (part->type() == PT_NOISE) {
1462 noise_it.add_to_end(part);
1463 } else {
1464 AddToTempPartList(part, &temp_part_list);
1465 }
1466 }
1467 EmptyTempPartList(&temp_part_list, &work_set);
1468 // Now finish all working sets and transfer ColPartitionSets to block_sets.
1469 WorkingPartSet_IT work_it(&work_set);
1470 while (!work_it.empty()) {
1471 WorkingPartSet *working_set = work_it.extract();
1472 working_set->ExtractCompletedBlocks(bleft_, tright_, resolution_, &good_parts_, blocks,
1473 to_blocks);
1474 delete working_set;
1475 work_it.forward();
1476 }
1477 }
1478
1479 // Helper reflects a list of blobs in the y-axis.
1480 // Only reflects the BLOBNBOX bounding box. Not the blobs or outlines below.
1481 static void ReflectBlobList(BLOBNBOX_LIST *bblobs) {
1482 BLOBNBOX_IT it(bblobs);
1483 for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
1484 it.data()->reflect_box_in_y_axis();
1485 }
1486 }
1487
1488 // Reflect the blob boxes (but not the outlines) in the y-axis so that
1489 // the blocks get created in the correct RTL order. Reflects the blobs
1490 // in the input_block and the bblobs list.
1491 // The reflection is undone in RotateAndReskewBlocks by
1492 // reflecting the blocks themselves, and then recomputing the blob bounding
1493 // boxes.
1494 void ColumnFinder::ReflectForRtl(TO_BLOCK *input_block, BLOBNBOX_LIST *bblobs) {
1495 ReflectBlobList(bblobs);
1496 ReflectBlobList(&input_block->blobs);
1497 ReflectBlobList(&input_block->small_blobs);
1498 ReflectBlobList(&input_block->noise_blobs);
1499 ReflectBlobList(&input_block->large_blobs);
1500 // Update the denorm with the reflection.
1501 auto *new_denorm = new DENORM;
1502 new_denorm->SetupNormalization(nullptr, nullptr, denorm_, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, 0.0f);
1503 denorm_ = new_denorm;
1504 }
1505
1506 // Helper fixes up blobs and cblobs to match the desired rotation,
1507 // exploding multi-outline blobs back to single blobs and accumulating
1508 // the bounding box widths and heights.
1509 static void RotateAndExplodeBlobList(const FCOORD &blob_rotation, BLOBNBOX_LIST *bblobs,
1510 STATS *widths, STATS *heights) {
1511 BLOBNBOX_IT it(bblobs);
1512 for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
1513 BLOBNBOX *blob = it.data();
1514 C_BLOB *cblob = blob->cblob();
1515 C_OUTLINE_LIST *outlines = cblob->out_list();
1516 C_OUTLINE_IT ol_it(outlines);
1517 if (!outlines->singleton()) {
1518 // This blob has multiple outlines from CJK repair.
1519 // Explode the blob back into individual outlines.
1520 for (; !ol_it.empty(); ol_it.forward()) {
1521 C_OUTLINE *outline = ol_it.extract();
1522 BLOBNBOX *new_blob = BLOBNBOX::RealBlob(outline);
1523 // This blob will be revisited later since we add_after_stay_put here.
1524 // This means it will get rotated and have its width/height added to
1525 // the stats below.
1526 it.add_after_stay_put(new_blob);
1527 }
1528 it.extract();
1529 delete blob;
1530 } else {
1531 if (blob_rotation.x() != 1.0f || blob_rotation.y() != 0.0f) {
1532 cblob->rotate(blob_rotation);
1533 }
1534 blob->compute_bounding_box();
1535 widths->add(blob->bounding_box().width(), 1);
1536 heights->add(blob->bounding_box().height(), 1);
1537 }
1538 }
1539 }
1540
1541 // Undo the deskew that was done in FindTabVectors, as recognition is done
1542 // without correcting blobs or blob outlines for skew.
1543 // Reskew the completed blocks to put them back to the original rotated coords
1544 // that were created by CorrectOrientation.
1545 // If the input_is_rtl, then reflect the blocks in the y-axis to undo the
1546 // reflection that was done before FindTabVectors.
1547 // Blocks that were identified as vertical text (relative to the rotated
1548 // coordinates) are further rotated so the text lines are horizontal.
1549 // blob polygonal outlines are rotated to match the position of the blocks
1550 // that they are in, and their bounding boxes are recalculated to be accurate.
1551 // Record appropriate inverse transformations and required
1552 // classifier transformation in the blocks.
1553 void ColumnFinder::RotateAndReskewBlocks(bool input_is_rtl, TO_BLOCK_LIST *blocks) {
1554 if (input_is_rtl) {
1555 // The skew is backwards because of the reflection.
1556 FCOORD tmp = deskew_;
1557 deskew_ = reskew_;
1558 reskew_ = tmp;
1559 }
1560 TO_BLOCK_IT it(blocks);
1561 int block_index = 1;
1562 for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
1563 TO_BLOCK *to_block = it.data();
1564 BLOCK *block = to_block->block;
1565 // Blocks are created on the deskewed blob outlines in TransformToBlocks()
1566 // so we need to reskew them back to page coordinates.
1567 if (input_is_rtl) {
1568 block->reflect_polygon_in_y_axis();
1569 }
1570 block->rotate(reskew_);
1571 // Copy the right_to_left flag to the created block.
1572 block->set_right_to_left(input_is_rtl);
1573 // Save the skew angle in the block for baseline computations.
1574 block->set_skew(reskew_);
1575 block->pdblk.set_index(block_index++);
1576 FCOORD blob_rotation = ComputeBlockAndClassifyRotation(block);
1577 // Rotate all the blobs if needed and recompute the bounding boxes.
1578 // Compute the block median blob width and height as we go.
1579 STATS widths(0, block->pdblk.bounding_box().width() - 1);
1580 STATS heights(0, block->pdblk.bounding_box().height() - 1);
1581 RotateAndExplodeBlobList(blob_rotation, &to_block->blobs, &widths, &heights);
1582 TO_ROW_IT row_it(to_block->get_rows());
1583 for (row_it.mark_cycle_pt(); !row_it.cycled_list(); row_it.forward()) {
1584 TO_ROW *row = row_it.data();
1585 RotateAndExplodeBlobList(blob_rotation, row->blob_list(), &widths, &heights);
1586 }
1587 block->set_median_size(static_cast<int>(widths.median() + 0.5),
1588 static_cast<int>(heights.median() + 0.5));
1589 if (textord_debug_tabfind >= 2) {
1590 tprintf("Block median size = (%d, %d)\n", block->median_size().x(), block->median_size().y());
1591 }
1592 }
1593 }
1594
1595 // Computes the rotations for the block (to make textlines horizontal) and
1596 // for the blobs (for classification) and sets the appropriate members
1597 // of the given block.
1598 // Returns the rotation that needs to be applied to the blobs to make
1599 // them sit in the rotated block.
1600 FCOORD ColumnFinder::ComputeBlockAndClassifyRotation(BLOCK *block) {
1601 // The text_rotation_ tells us the gross page text rotation that needs
1602 // to be applied for classification
1603 // TODO(rays) find block-level classify rotation by orientation detection.
1604 // In the mean time, assume that "up" for text printed in the minority
1605 // direction (PT_VERTICAL_TEXT) is perpendicular to the line of reading.
1606 // Accomplish this by zero-ing out the text rotation. This covers the
1607 // common cases of image credits in documents written in Latin scripts
1608 // and page headings for predominantly vertically written CJK books.
1609 FCOORD classify_rotation(text_rotation_);
1610 FCOORD block_rotation(1.0f, 0.0f);
1611 if (block->pdblk.poly_block()->isA() == PT_VERTICAL_TEXT) {
1612 // Vertical text needs to be 90 degrees rotated relative to the rest.
1613 // If the rest has a 90 degree rotation already, use the inverse, making
1614 // the vertical text the original way up. Otherwise use 90 degrees
1615 // clockwise.
1616 if (rerotate_.x() == 0.0f) {
1617 block_rotation = rerotate_;
1618 } else {
1619 block_rotation = FCOORD(0.0f, -1.0f);
1620 }
1621 block->rotate(block_rotation);
1622 classify_rotation = FCOORD(1.0f, 0.0f);
1623 }
1624 block_rotation.rotate(rotation_);
1625 // block_rotation is now what we have done to the blocks. Now do the same
1626 // thing to the blobs, but save the inverse rotation in the block, as that
1627 // is what we need to DENORM back to the image coordinates.
1628 FCOORD blob_rotation(block_rotation);
1629 block_rotation.set_y(-block_rotation.y());
1630 block->set_re_rotation(block_rotation);
1631 block->set_classify_rotation(classify_rotation);
1632 if (textord_debug_tabfind) {
1633 tprintf("Blk %d, type %d rerotation(%.2f, %.2f), char(%.2f,%.2f), box:", block->pdblk.index(),
1634 block->pdblk.poly_block()->isA(), block->re_rotation().x(), block->re_rotation().y(),
1635 classify_rotation.x(), classify_rotation.y());
1636 block->pdblk.bounding_box().print();
1637 }
1638 return blob_rotation;
1639 }
1640
1641 } // namespace tesseract.