25 const int CubeLineSegmenter::kLineSepMorphMinHgt = 20;
26 const int CubeLineSegmenter::kHgtBins = 20;
27 const double CubeLineSegmenter::kMaxValidLineRatio = 3.2;
28 const int CubeLineSegmenter::kMaxConnCompHgt = 150;
29 const int CubeLineSegmenter::kMaxConnCompWid = 500;
30 const int CubeLineSegmenter::kMaxHorzAspectRatio = 50;
31 const int CubeLineSegmenter::kMaxVertAspectRatio = 20;
32 const int CubeLineSegmenter::kMinWid = 2;
33 const int CubeLineSegmenter::kMinHgt = 2;
34 const float CubeLineSegmenter::kMinValidLineHgtRatio = 2.5;
55 if (lines_pixa_ !=
NULL) {
56 pixaDestroy(&lines_pixa_);
60 if (con_comps_ !=
NULL) {
61 pixaDestroy(&con_comps_);
65 if (columns_ !=
NULL) {
66 pixaaDestroy(&columns_);
72 double CubeLineSegmenter::ValidityRatio(Pix *line_mask_pix, Box *line_box) {
73 return line_box->h / est_alef_hgt_;
77 bool CubeLineSegmenter::ValidLine(Pix *line_mask_pix, Box *line_box) {
78 double validity_ratio = ValidityRatio(line_mask_pix, line_box);
80 return validity_ratio < kMaxValidLineRatio;
85 Pixa *CubeLineSegmenter::VerticalClosing(Pix *pix,
86 int threshold, Boxa **boxa) {
87 char sequence_str[16];
90 sprintf(sequence_str,
"c100.%d", threshold);
91 Pix *morphed_pix = pixMorphCompSequence(pix, sequence_str, 0);
92 if (morphed_pix ==
NULL) {
98 (*boxa) = pixConnComp(morphed_pix, &pixac, 8);
100 pixDestroy(&morphed_pix);
102 if ((*boxa) ==
NULL) {
110 Pixa *CubeLineSegmenter::CrackLine(Pix *cracked_line_pix,
111 Box *cracked_line_box,
int line_cnt) {
113 Pixa **lines_pixa =
new Pixa*[line_cnt];
114 if (lines_pixa ==
NULL) {
118 memset(lines_pixa, 0, line_cnt *
sizeof(*lines_pixa));
121 Pixa *line_con_comps_pix;
122 Boxa *line_con_comps = ComputeLineConComps(cracked_line_pix,
123 cracked_line_box, &line_con_comps_pix);
125 if (line_con_comps ==
NULL) {
131 for (
int con = 0; con < line_con_comps->n; con++) {
132 Box *con_box = line_con_comps->box[con];
133 Pix *con_pix = line_con_comps_pix->pix[con];
134 int mid_y = (con_box->y - cracked_line_box->y) + (con_box->h / 2),
135 line_idx =
MIN(line_cnt - 1,
136 (mid_y * line_cnt / cracked_line_box->h));
139 if (lines_pixa[line_idx] ==
NULL) {
140 lines_pixa[line_idx] = pixaCreate(line_con_comps->n);
141 if (lines_pixa[line_idx] ==
NULL) {
143 boxaDestroy(&line_con_comps);
144 pixaDestroy(&line_con_comps_pix);
150 if (pixaAddPix(lines_pixa[line_idx], con_pix, L_CLONE) != 0 ||
151 pixaAddBox(lines_pixa[line_idx], con_box, L_CLONE)) {
153 boxaDestroy(&line_con_comps);
154 pixaDestroy(&line_con_comps_pix);
159 Pixa *lines = pixaCreate(line_cnt);
163 for (
int line = 0; line < line_cnt; line++) {
164 Pixa *line_pixa = lines_pixa[line];
167 if (line_pixa ==
NULL) {
174 Pix *line_pix = Pixa2Pix(line_pixa, &line_box);
175 if (line_pix ==
NULL ||
177 ValidLine(line_pix, line_box) ==
false ||
178 pixaAddPix(lines, line_pix, L_INSERT) != 0 ||
179 pixaAddBox(lines, line_box, L_INSERT) != 0) {
180 if (line_pix !=
NULL) {
181 pixDestroy(&line_pix);
184 if (line_box !=
NULL) {
185 boxDestroy(&line_box);
195 for (
int line = 0; line < line_cnt; line++) {
196 if (lines_pixa[line] !=
NULL) {
197 pixaDestroy(&lines_pixa[line]);
202 boxaDestroy(&line_con_comps);
203 pixaDestroy(&line_con_comps_pix);
205 if (success ==
false) {
214 Pixa *CubeLineSegmenter::CrackLine(Pix *cracked_line_pix,
215 Box *cracked_line_box) {
217 int max_line_cnt =
static_cast<int>((cracked_line_box->h /
218 est_alef_hgt_) + 0.5);
219 if (max_line_cnt < 2) {
223 for (
int line_cnt = 2; line_cnt < max_line_cnt; line_cnt++) {
224 Pixa *lines = CrackLine(cracked_line_pix, cracked_line_box, line_cnt);
234 Pixa *CubeLineSegmenter::SplitLine(Pix *line_mask_pix, Box *line_box) {
236 Pix *line_pix = pixClone(line_mask_pix);
238 if (line_pix ==
NULL) {
243 pixRasterop(line_pix, 0, 0, line_pix->w, line_pix->h,
244 PIX_SRC & PIX_DST, img_, line_box->x, line_box->y);
248 int morph_hgt = kLineSepMorphMinHgt - 1,
249 best_threshold = kLineSepMorphMinHgt - 1,
250 max_valid_portion = 0;
256 pixac = VerticalClosing(line_pix, morph_hgt, &boxa);
264 for (line = 0; line < pixac->n; line++) {
265 boxa->box[line]->x += line_box->x;
266 boxa->box[line]->y += line_box->y;
268 if (ValidLine(pixac->pix[line], boxa->box[line]) ==
true) {
273 valid_portion += boxa->box[line]->h;
278 if (valid_line_cnt == pixac->n) {
280 pixDestroy(&line_pix);
285 if (valid_portion > max_valid_portion) {
286 max_valid_portion = valid_portion;
287 best_threshold = morph_hgt;
295 while (morph_hgt > 0);
299 pixac = CrackLine(line_pix, line_box);
301 pixDestroy(&line_pix);
307 if (max_valid_portion > 0) {
309 pixac = VerticalClosing(line_pix, best_threshold, &boxa);
313 for (
int line = 0; line < pixac->n; line++) {
314 boxa->box[line]->x += line_box->x;
315 boxa->box[line]->y += line_box->y;
318 if (ValidLine(pixac->pix[line], boxa->box[line]) ==
false) {
319 pixaRemovePix(pixac, line);
325 pixDestroy(&line_pix);
330 pixDestroy(&line_pix);
336 bool CubeLineSegmenter::SmallLine(Box *line_box) {
337 return line_box->h <= (kMinValidLineHgtRatio * est_dot_hgt_);
341 Boxa * CubeLineSegmenter::ComputeLineConComps(Pix *line_mask_pix,
343 Pixa **con_comps_pixa) {
345 Pix *line_pix = pixClone(line_mask_pix);
347 if (line_pix ==
NULL) {
352 pixRasterop(line_pix, 0, 0, line_pix->w, line_pix->h,
353 PIX_SRC & PIX_DST, img_, line_box->x, line_box->y);
356 Boxa *line_con_comps = pixConnComp(line_pix, con_comps_pixa, 8);
358 pixDestroy(&line_pix);
361 for (
int con = 0; con < line_con_comps->n; con++) {
362 line_con_comps->box[con]->x += line_box->x;
363 line_con_comps->box[con]->y += line_box->y;
366 return line_con_comps;
370 Pix *CubeLineSegmenter::PixUnion(Pix *dest_pix, Box *dest_box,
371 Pix *src_pix, Box *src_box) {
373 BOX *union_box = boxBoundingRegion(src_box, dest_box);
376 Pix *union_pix = pixCreate(union_box->w, union_box->h, src_pix->d);
377 if (union_pix ==
NULL) {
382 pixRasterop(union_pix,
383 src_box->x - union_box->x, src_box->y - union_box->y,
384 src_box->w, src_box->h, PIX_SRC | PIX_DST, src_pix, 0, 0);
386 pixRasterop(union_pix,
387 dest_box->x - union_box->x, dest_box->y - union_box->y,
388 dest_box->w, dest_box->h, PIX_SRC | PIX_DST, dest_pix, 0, 0);
391 *dest_box = *union_box;
393 boxDestroy(&union_box);
399 Pix *CubeLineSegmenter::Pixa2Pix(Pixa *pixa, Box **dest_box,
400 int start_pix,
int pix_cnt) {
407 for (
int pix_idx = start_pix; pix_idx < (start_pix + pix_cnt); pix_idx++) {
408 Box *pix_box = pixa->boxa->box[pix_idx];
410 UpdateRange(pix_box->x, pix_box->x + pix_box->w, &min_x, &max_x);
411 UpdateRange(pix_box->y, pix_box->y + pix_box->h, &min_y, &max_y);
414 (*dest_box) = boxCreate(min_x, min_y, max_x - min_x, max_y - min_y);
415 if ((*dest_box) ==
NULL) {
420 Pix *union_pix = pixCreate((*dest_box)->w, (*dest_box)->h, img_->d);
421 if (union_pix ==
NULL) {
422 boxDestroy(dest_box);
428 for (
int pix_idx = start_pix; pix_idx < (start_pix + pix_cnt); pix_idx++) {
429 Box *pix_box = pixa->boxa->box[pix_idx];
430 Pix *con_pix = pixa->pix[pix_idx];
432 pixRasterop(union_pix,
433 pix_box->x - (*dest_box)->x, pix_box->y - (*dest_box)->y,
434 pix_box->w, pix_box->h, PIX_SRC | PIX_DST, con_pix, 0, 0);
441 Pix *CubeLineSegmenter::Pixa2Pix(Pixa *pixa, Box **dest_box) {
442 return Pixa2Pix(pixa, dest_box, 0, pixa->n);
446 bool CubeLineSegmenter::MergeLine(Pix *line_mask_pix, Box *line_box,
447 Pixa *lines, Boxaa *lines_con_comps) {
449 Pixa *small_con_comps_pix;
450 Boxa *small_line_con_comps = ComputeLineConComps(line_mask_pix,
451 line_box, &small_con_comps_pix);
453 if (small_line_con_comps ==
NULL) {
458 for (
int con = 0; con < small_line_con_comps->n; con++) {
459 Box *small_con_comp_box = small_line_con_comps->box[con];
462 small_box_right = small_con_comp_box->x + small_con_comp_box->w,
463 small_box_bottom = small_con_comp_box->y + small_con_comp_box->h;
466 for (
int line = 0; line < lines->n; line++) {
467 if (SmallLine(lines->boxa->box[line]) ==
true) {
472 Boxa *line_con_comps = lines_con_comps->boxa[line];
474 for (
int lcon = 0; lcon < line_con_comps->n; lcon++) {
475 Box *con_comp_box = line_con_comps->box[lcon];
478 box_right = con_comp_box->x + con_comp_box->w,
479 box_bottom = con_comp_box->y + con_comp_box->h;
481 xdist =
MAX(small_con_comp_box->x, con_comp_box->x) -
482 MIN(small_box_right, box_right);
484 ydist =
MAX(small_con_comp_box->y, con_comp_box->y) -
485 MIN(small_box_bottom, box_bottom);
489 if (best_line == -1 || ydist < best_dist) {
498 if (best_line != -1 && best_dist < est_alef_hgt_) {
500 Pix *
new_line = PixUnion(lines->pix[best_line],
501 lines->boxa->box[best_line],
502 small_con_comps_pix->pix[con], small_con_comp_box);
504 if (new_line ==
NULL) {
508 pixDestroy(&lines->pix[best_line]);
513 pixaDestroy(&small_con_comps_pix);
514 boxaDestroy(&small_line_con_comps);
520 bool CubeLineSegmenter::AddLines(Pixa *lines) {
523 Boxaa *lines_con_comps = boxaaCreate(lines->n);
524 if (lines_con_comps ==
NULL) {
528 for (
int line = 0; line < lines->n; line++) {
530 if (ValidLine(lines->pix[line], lines->boxa->box[line]) ==
false) {
532 Pixa *split_lines = SplitLine(lines->pix[line],
533 lines->boxa->box[line]);
536 if (pixaRemovePix(lines, line) != 0) {
542 if (split_lines ==
NULL) {
547 for (
int s_line = 0; s_line < split_lines->n; s_line++) {
548 Pix *sp_line = pixaGetPix(split_lines, s_line, L_CLONE);
549 Box *sp_box = boxaGetBox(split_lines->boxa, s_line, L_CLONE);
551 if (sp_line ==
NULL || sp_box ==
NULL) {
556 if (pixaInsertPix(lines, ++line, sp_line, sp_box) != 0) {
562 pixaDestroy(&split_lines);
567 for (
int line = 0; line < lines->n; line++) {
568 Boxa *line_con_comps = ComputeLineConComps(lines->pix[line],
569 lines->boxa->box[line],
NULL);
571 if (line_con_comps ==
NULL) {
576 if (boxaaAddBoxa(lines_con_comps, line_con_comps, L_INSERT) != 0) {
583 for (
int line = 0; line < lines->n; line++) {
585 if (SmallLine(lines->boxa->box[line]) ==
true) {
587 if (MergeLine(lines->pix[line], lines->boxa->box[line],
588 lines, lines_con_comps) ==
true) {
590 if (pixaRemovePix(lines, line) != 0) {
594 if (boxaaRemoveBoxa(lines_con_comps, line) != 0) {
603 boxaaDestroy(&lines_con_comps);
606 if (pixaaAddPixa(columns_, lines, L_INSERT) != 0) {
614 int *CubeLineSegmenter::IndexRTL(Pixa *pixa) {
615 int *pix_index =
new int[pixa->n];
616 if (pix_index ==
NULL) {
620 for (
int pix = 0; pix < pixa->n; pix++) {
621 pix_index[pix] = pix;
624 for (
int ipix = 0; ipix < pixa->n; ipix++) {
625 for (
int jpix = ipix + 1; jpix < pixa->n; jpix++) {
626 Box *ipix_box = pixa->boxa->box[pix_index[ipix]],
627 *jpix_box = pixa->boxa->box[pix_index[jpix]];
630 if ((ipix_box->x + ipix_box->w) < (jpix_box->x + jpix_box->w)) {
631 int temp = pix_index[ipix];
632 pix_index[ipix] = pix_index[jpix];
633 pix_index[jpix] = temp;
642 bool CubeLineSegmenter::LineSegment() {
646 Pix *pix_temp1 = pixMorphCompSequence(img_,
"c5.500", 0);
647 if (pix_temp1 ==
NULL) {
653 Boxa *boxa = pixConnComp(pix_temp1, &pixam, 8);
659 int init_morph_min_hgt = kLineSepMorphMinHgt;
660 char sequence_str[16];
661 sprintf(sequence_str,
"c100.%d", init_morph_min_hgt);
664 Pixa *pixad = pixaMorphSequenceByRegion(img_, pixam, sequence_str, 0, 0);
670 int col_cnt = boxaGetCount(boxa);
673 columns_ = pixaaCreate(col_cnt);
674 if (columns_ ==
NULL) {
679 int *col_order = IndexRTL(pixad);
680 if (col_order ==
NULL) {
686 for (
int col_idx = 0; col_idx < col_cnt; col_idx++) {
687 int col = col_order[col_idx];
690 Pix *pixt3 = pixaGetPix(pixad, col, L_CLONE);
695 Box *col_box = pixad->boxa->box[col];
698 Boxa *boxa2 = pixConnComp(pixt3, &pixac, 8);
704 for (
int line = 0; line < pixac->n; line++) {
705 pixac->boxa->box[line]->x += col_box->x;
706 pixac->boxa->box[line]->y += col_box->y;
710 if (AddLines(pixac) ==
true) {
711 if (pixaaAddBox(columns_, col_box, L_CLONE) != 0) {
719 line_cnt_ += columns_->pixa[col_idx]->n;
727 pixDestroy(&pix_temp1);
733 bool CubeLineSegmenter::EstimateFontParams() {
734 int hgt_hist[kHgtBins];
739 memset(hgt_hist, 0,
sizeof(hgt_hist));
744 for (
int con = 0; con < con_comps_->n; con++) {
746 if (con_comps_->boxa->box[con]->h > kMaxConnCompHgt ||
747 con_comps_->boxa->box[con]->w > kMaxConnCompWid) {
751 max_hgt =
MAX(max_hgt, con_comps_->boxa->box[con]->h);
759 memset(hgt_hist, 0,
sizeof(hgt_hist));
763 for (
int con = 0; con < con_comps_->n; con++) {
765 if (con_comps_->boxa->box[con]->h > kMaxConnCompHgt ||
766 con_comps_->boxa->box[con]->w > kMaxConnCompWid) {
770 int bin =
static_cast<int>(kHgtBins * con_comps_->boxa->box[con]->h /
772 bin =
MIN(bin, kHgtBins - 1);
774 mean_hgt += con_comps_->boxa->box[con]->h;
777 mean_hgt /= con_comps_->n;
782 for (
int bin = 0; bin < kHgtBins; bin++) {
786 for (
int ibin = 0; ibin < 2; ibin++) {
787 for (
int jbin = ibin + 1; jbin < kHgtBins; jbin++) {
788 if (hgt_hist[idx[ibin]] < hgt_hist[idx[jbin]]) {
789 int swap = idx[ibin];
790 idx[ibin] = idx[jbin];
798 est_dot_hgt_ = (1.0 * (idx[0] + 1) * max_hgt / kHgtBins);
799 est_alef_hgt_ = (1.0 * (idx[1] + 1) * max_hgt / kHgtBins);
802 if (est_alef_hgt_ < (est_dot_hgt_ * 2)) {
804 est_alef_hgt_ = mean_hgt * 1.5;
805 est_dot_hgt_ = est_alef_hgt_ / 5.0;
808 est_alef_hgt_ =
MAX(est_alef_hgt_, est_dot_hgt_ * 4.0);
814 Pix *CubeLineSegmenter::CleanUp(Pix *orig_img) {
816 Pix *pix_temp0 = pixMorphCompSequence(orig_img,
"o300.2", 0);
817 pixXor(pix_temp0, pix_temp0, orig_img);
820 Pix *pix_temp1 = pixMorphCompSequence(pix_temp0,
"o2.300", 0);
821 pixXor(pix_temp1, pix_temp1, pix_temp0);
823 pixDestroy(&pix_temp0);
827 Boxa *boxa = pixConnComp(pix_temp1, &con_comps, 8);
833 for (
int con = 0; con < con_comps->n; con++) {
834 Box *box = boxa->box[con];
837 if ((box->w > (box->h * kMaxHorzAspectRatio)) ||
838 (box->h > (box->w * kMaxVertAspectRatio)) ||
839 (box->w < kMinWid && box->h < kMinHgt)) {
840 pixRasterop(pix_temp1, box->x, box->y, box->w, box->h,
841 PIX_SRC ^ PIX_DST, con_comps->pix[con], 0, 0);
845 pixaDestroy(&con_comps);
852 bool CubeLineSegmenter::Init() {
857 if (orig_img_ ==
NULL) {
867 if (init_ ==
false && Init() ==
false) {
871 if (line < 0 || line >= line_cnt_) {
875 (*line_box) = lines_pixa_->boxa->box[line];
876 return lines_pixa_->pix[line];
882 bool CubeLineSegmenter::FindLines() {
884 Pix *gray_scale_img =
NULL;
885 if (orig_img_->d != 2 && orig_img_->d != 8) {
886 gray_scale_img = pixConvertTo8(orig_img_,
false);
887 if (gray_scale_img ==
NULL) {
891 gray_scale_img = orig_img_;
895 Pix *thresholded_img;
896 thresholded_img = pixThresholdToBinary(gray_scale_img, 128);
898 if (gray_scale_img != orig_img_) {
899 pixDestroy(&gray_scale_img);
902 if (thresholded_img ==
NULL) {
907 Pix *deskew_img = pixDeskew(thresholded_img, 2);
908 if (deskew_img ==
NULL) {
912 pixDestroy(&thresholded_img);
914 img_ = CleanUp(deskew_img);
915 pixDestroy(&deskew_img);
920 pixDestroy(&deskew_img);
923 Boxa *boxa = pixConnComp(img_, &con_comps_, 8);
931 if (EstimateFontParams() ==
false) {
936 if (LineSegment() ==
false) {