/********************************************************************** * File: oldbasel.cpp (Formerly oldbl.c) * Description: A re-implementation of the old baseline algorithm. * Author: Ray Smith * Created: Wed Oct 6 09:41:48 BST 1993 * * (C) Copyright 1993, Hewlett-Packard Ltd. ** Licensed under the Apache License, Version 2.0 (the "License"); ** you may not use this file except in compliance with the License. ** You may obtain a copy of the License at ** http://www.apache.org/licenses/LICENSE-2.0 ** Unless required by applicable law or agreed to in writing, software ** distributed under the License is distributed on an "AS IS" BASIS, ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. ** See the License for the specific language governing permissions and ** limitations under the License. * **********************************************************************/ #include "mfcpch.h" #include "ccstruct.h" #include "statistc.h" #include "quadlsq.h" #include "detlinefit.h" #include "makerow.h" #include "drawtord.h" #include "oldbasel.h" #include "textord.h" #include "tprintf.h" // Include automatically generated configuration file if running autoconf. #ifdef HAVE_CONFIG_H #include "config_auto.h" #endif #define EXTERN EXTERN BOOL_VAR (textord_really_old_xheight, FALSE, "Use original wiseowl xheight"); EXTERN BOOL_VAR (textord_oldbl_debug, FALSE, "Debug old baseline generation"); EXTERN BOOL_VAR (textord_debug_baselines, FALSE, "Debug baseline generation"); EXTERN BOOL_VAR (textord_oldbl_paradef, TRUE, "Use para default mechanism"); EXTERN BOOL_VAR (textord_oldbl_split_splines, TRUE, "Split stepped splines"); EXTERN BOOL_VAR (textord_oldbl_merge_parts, TRUE, "Merge suspect partitions"); EXTERN BOOL_VAR (oldbl_corrfix, TRUE, "Improve correlation of heights"); EXTERN BOOL_VAR (oldbl_xhfix, FALSE, "Fix bug in modes threshold for xheights"); EXTERN BOOL_VAR(textord_ocropus_mode, FALSE, "Make baselines for ocropus"); EXTERN double_VAR (oldbl_xhfract, 0.4, "Fraction of est allowed in calc"); EXTERN INT_VAR (oldbl_holed_losscount, 10, "Max lost before fallback line used"); EXTERN double_VAR (oldbl_dot_error_size, 1.26, "Max aspect ratio of a dot"); EXTERN double_VAR (textord_oldbl_jumplimit, 0.15, "X fraction for new partition"); #define TURNLIMIT 1 /*min size for turning point */ #define X_HEIGHT_FRACTION 0.7 /*x-height/caps height */ #define DESCENDER_FRACTION 0.5 /*descender/x-height */ #define MIN_ASC_FRACTION 0.20 /*min size of ascenders */ #define MIN_DESC_FRACTION 0.25 /*min size of descenders */ #define MINASCRISE 2.0 /*min ascender/desc step */ #define MAXHEIGHTVARIANCE 0.15 /*accepted variation in x-height */ #define MAXHEIGHT 300 /*max blob height */ #define MAXOVERLAP 0.1 /*max 10% missed overlap */ #define MAXBADRUN 2 /*max non best for failed */ #define HEIGHTBUCKETS 200 /* Num of buckets */ #define DELTAHEIGHT 5.0 /* Small amount of diff */ #define GOODHEIGHT 5 #define MAXLOOPS 10 #define MODENUM 10 #define MAXPARTS 6 #define SPLINESIZE 23 #define ABS(x) ((x)<0 ? (-(x)) : (x)) namespace tesseract { /********************************************************************** * make_old_baselines * * Top level function to make baselines the old way. **********************************************************************/ void Textord::make_old_baselines(TO_BLOCK *block, // block to do BOOL8 testing_on, // correct orientation float gradient) { QSPLINE *prev_baseline; // baseline of previous row TO_ROW *row; // current row TO_ROW_IT row_it = block->get_rows(); BLOBNBOX_IT blob_it; prev_baseline = NULL; // nothing yet for (row_it.mark_cycle_pt(); !row_it.cycled_list(); row_it.forward()) { row = row_it.data(); find_textlines(block, row, 2, NULL); if (row->xheight <= 0 && prev_baseline != NULL) find_textlines(block, row, 2, prev_baseline); if (row->xheight > 0) { // was a good one prev_baseline = &row->baseline; } else { prev_baseline = NULL; blob_it.set_to_list(row->blob_list()); if (textord_debug_baselines) tprintf("Row baseline generation failed on row at (%d,%d)\n", blob_it.data()->bounding_box().left(), blob_it.data()->bounding_box().bottom()); } } correlate_lines(block, gradient); block->block->set_xheight(block->xheight); } /********************************************************************** * correlate_lines * * Correlate the x-heights and ascender heights of a block to fill-in * the ascender height and descender height for rows without one. * Also fix baselines of rows without a decent fit. **********************************************************************/ void Textord::correlate_lines(TO_BLOCK *block, float gradient) { TO_ROW **rows; //array of ptrs int rowcount; /*no of rows to do */ register int rowindex; /*no of row */ //iterator TO_ROW_IT row_it = block->get_rows (); rowcount = row_it.length (); if (rowcount == 0) { //default value block->xheight = block->line_size; return; /*none to do */ } rows = (TO_ROW **) alloc_mem (rowcount * sizeof (TO_ROW *)); rowindex = 0; for (row_it.mark_cycle_pt (); !row_it.cycled_list (); row_it.forward ()) //make array rows[rowindex++] = row_it.data (); /*try to fix bad lines */ correlate_neighbours(block, rows, rowcount); if (textord_really_old_xheight || textord_old_xheight) { block->xheight = (float) correlate_with_stats(rows, rowcount, block); if (block->xheight <= 0) block->xheight = block->line_size * tesseract::CCStruct::kXHeightFraction; if (block->xheight < textord_min_xheight) block->xheight = (float) textord_min_xheight; } else { compute_block_xheight(block, gradient); } free_mem(rows); } /********************************************************************** * correlate_neighbours * * Try to fix rows that had a bad spline fit by using neighbours. **********************************************************************/ void Textord::correlate_neighbours(TO_BLOCK *block, // block rows are in. TO_ROW **rows, // rows of block. int rowcount) { // no of rows to do. TO_ROW *row; /*current row */ register int rowindex; /*no of row */ register int otherrow; /*second row */ int upperrow; /*row above to use */ int lowerrow; /*row below to use */ float biggest; for (rowindex = 0; rowindex < rowcount; rowindex++) { row = rows[rowindex]; /*current row */ if (row->xheight < 0) { /*quadratic failed */ for (otherrow = rowindex - 2; otherrow >= 0 && (rows[otherrow]->xheight < 0.0 || !row->baseline.overlap (&rows[otherrow]->baseline, MAXOVERLAP)); otherrow--); upperrow = otherrow; /*decent row above */ for (otherrow = rowindex + 1; otherrow < rowcount && (rows[otherrow]->xheight < 0.0 || !row->baseline.overlap (&rows[otherrow]->baseline, MAXOVERLAP)); otherrow++); lowerrow = otherrow; /*decent row below */ if (upperrow >= 0) find_textlines(block, row, 2, &rows[upperrow]->baseline); if (row->xheight < 0 && lowerrow < rowcount) find_textlines(block, row, 2, &rows[lowerrow]->baseline); if (row->xheight < 0) { if (upperrow >= 0) find_textlines(block, row, 1, &rows[upperrow]->baseline); else if (lowerrow < rowcount) find_textlines(block, row, 1, &rows[lowerrow]->baseline); } } } for (biggest = 0.0f, rowindex = 0; rowindex < rowcount; rowindex++) { row = rows[rowindex]; /*current row */ if (row->xheight < 0) /*linear failed */ /*make do */ row->xheight = -row->xheight; biggest = MAX (biggest, row->xheight); } } /********************************************************************** * correlate_with_stats * * correlate the x-heights and ascender heights of a block to fill-in * the ascender height and descender height for rows without one. **********************************************************************/ int Textord::correlate_with_stats(TO_ROW **rows, // rows of block. int rowcount, // no of rows to do. TO_BLOCK* block) { TO_ROW *row; /*current row */ register int rowindex; /*no of row */ float lineheight; /*mean x-height */ float ascheight; /*average ascenders */ float minascheight; /*min allowed ascheight */ int xcount; /*no of samples for xheight */ float fullheight; /*mean top height */ int fullcount; /*no of samples */ float descheight; /*mean descender drop */ float mindescheight; /*min allowed descheight */ int desccount; /*no of samples */ float xshift; /*shift in xheight */ /*no samples */ xcount = fullcount = desccount = 0; lineheight = ascheight = fullheight = descheight = 0.0; for (rowindex = 0; rowindex < rowcount; rowindex++) { row = rows[rowindex]; /*current row */ if (row->ascrise > 0.0) { /*got ascenders? */ lineheight += row->xheight;/*average x-heights */ ascheight += row->ascrise; /*average ascenders */ xcount++; } else { fullheight += row->xheight;/*assume full height */ fullcount++; } if (row->descdrop < 0.0) { /*got descenders? */ /*average descenders */ descheight += row->descdrop; desccount++; } } if (xcount > 0 && (!oldbl_corrfix || xcount >= fullcount)) { lineheight /= xcount; /*average x-height */ /*average caps height */ fullheight = lineheight + ascheight / xcount; /*must be decent size */ if (fullheight < lineheight * (1 + MIN_ASC_FRACTION)) fullheight = lineheight * (1 + MIN_ASC_FRACTION); } else { fullheight /= fullcount; /*average max height */ /*guess x-height */ lineheight = fullheight * X_HEIGHT_FRACTION; } if (desccount > 0 && (!oldbl_corrfix || desccount >= rowcount / 2)) descheight /= desccount; /*average descenders */ else /*guess descenders */ descheight = -lineheight * DESCENDER_FRACTION; if (lineheight > 0.0f) block->block->set_cell_over_xheight((fullheight - descheight) / lineheight); minascheight = lineheight * MIN_ASC_FRACTION; mindescheight = -lineheight * MIN_DESC_FRACTION; for (rowindex = 0; rowindex < rowcount; rowindex++) { row = rows[rowindex]; /*do each row */ row->all_caps = FALSE; if (row->ascrise / row->xheight < MIN_ASC_FRACTION) { /*no ascenders */ if (row->xheight >= lineheight * (1 - MAXHEIGHTVARIANCE) && row->xheight <= lineheight * (1 + MAXHEIGHTVARIANCE)) { row->ascrise = fullheight - lineheight; /*shift in x */ xshift = lineheight - row->xheight; /*set to average */ row->xheight = lineheight; } else if (row->xheight >= fullheight * (1 - MAXHEIGHTVARIANCE) && row->xheight <= fullheight * (1 + MAXHEIGHTVARIANCE)) { row->ascrise = row->xheight - lineheight; xshift = -row->ascrise; /*shift in x */ /*set to average */ row->xheight = lineheight; row->all_caps = TRUE; } else { row->ascrise = (fullheight - lineheight) * row->xheight / fullheight; xshift = -row->ascrise; /*shift in x */ /*scale it */ row->xheight -= row->ascrise; row->all_caps = TRUE; } if (row->ascrise < minascheight) row->ascrise = row->xheight * ((1.0 - X_HEIGHT_FRACTION) / X_HEIGHT_FRACTION); } if (row->descdrop > mindescheight) { if (row->xheight >= lineheight * (1 - MAXHEIGHTVARIANCE) && row->xheight <= lineheight * (1 + MAXHEIGHTVARIANCE)) /*set to average */ row->descdrop = descheight; else row->descdrop = -row->xheight * DESCENDER_FRACTION; } } return (int) lineheight; //block xheight } /********************************************************************** * find_textlines * * Compute the baseline for the given row. **********************************************************************/ void Textord::find_textlines(TO_BLOCK *block, // block row is in TO_ROW *row, // row to do int degree, // required approximation QSPLINE *spline) { // starting spline int partcount; /*no of partitions of */ BOOL8 holed_line = FALSE; //lost too many blobs int bestpart; /*biggest partition */ char *partids; /*partition no of each blob */ int partsizes[MAXPARTS]; /*no in each partition */ int lineheight; /*guessed x-height */ float jumplimit; /*allowed delta change */ int *xcoords; /*useful sample points */ int *ycoords; /*useful sample points */ TBOX *blobcoords; /*edges of blob rectangles */ int blobcount; /*no of blobs on line */ float *ydiffs; /*diffs from 1st approx */ int pointcount; /*no of coords */ int xstarts[SPLINESIZE + 1]; //segment boundaries int segments; //no of segments //no of blobs in row blobcount = row->blob_list ()->length (); partids = (char *) alloc_mem (blobcount * sizeof (char)); xcoords = (int *) alloc_mem (blobcount * sizeof (int)); ycoords = (int *) alloc_mem (blobcount * sizeof (int)); blobcoords = (TBOX *) alloc_mem (blobcount * sizeof (TBOX)); ydiffs = (float *) alloc_mem (blobcount * sizeof (float)); lineheight = get_blob_coords (row, (int) block->line_size, blobcoords, holed_line, blobcount); /*limit for line change */ jumplimit = lineheight * textord_oldbl_jumplimit; if (jumplimit < MINASCRISE) jumplimit = MINASCRISE; if (textord_oldbl_debug) { tprintf ("\nInput height=%g, Estimate x-height=%d pixels, jumplimit=%.2f\n", block->line_size, lineheight, jumplimit); } if (holed_line) make_holed_baseline (blobcoords, blobcount, spline, &row->baseline, row->line_m ()); else make_first_baseline (blobcoords, blobcount, xcoords, ycoords, spline, &row->baseline, jumplimit); #ifndef GRAPHICS_DISABLED if (textord_show_final_rows) row->baseline.plot (to_win, ScrollView::GOLDENROD); #endif if (blobcount > 1) { bestpart = partition_line (blobcoords, blobcount, &partcount, partids, partsizes, &row->baseline, jumplimit, ydiffs); pointcount = partition_coords (blobcoords, blobcount, partids, bestpart, xcoords, ycoords); segments = segment_spline (blobcoords, blobcount, xcoords, ycoords, degree, pointcount, xstarts); if (!holed_line) { do { row->baseline = QSPLINE (xstarts, segments, xcoords, ycoords, pointcount, degree); } while (textord_oldbl_split_splines && split_stepped_spline (&row->baseline, jumplimit / 2, xcoords, xstarts, segments)); } find_lesser_parts(row, blobcoords, blobcount, partids, partsizes, partcount, bestpart); } else { row->xheight = -1.0f; /*failed */ row->descdrop = 0.0f; row->ascrise = 0.0f; } row->baseline.extrapolate (row->line_m (), block->block->bounding_box ().left (), block->block->bounding_box ().right ()); if (textord_really_old_xheight) { old_first_xheight (row, blobcoords, lineheight, blobcount, &row->baseline, jumplimit); } else if (textord_old_xheight) { make_first_xheight (row, blobcoords, lineheight, (int) block->line_size, blobcount, &row->baseline, jumplimit); } else { compute_row_xheight(row, block->block->classify_rotation(), row->line_m(), block->line_size); } free_mem(partids); free_mem(xcoords); free_mem(ycoords); free_mem(blobcoords); free_mem(ydiffs); } } // namespace tesseract. /********************************************************************** * get_blob_coords * * Fill the blobcoords array with the coordinates of the blobs * in the row. The return value is the first guess at the line height. **********************************************************************/ int get_blob_coords( //get boxes TO_ROW *row, //row to use inT32 lineheight, //block level TBOX *blobcoords, //ouput boxes BOOL8 &holed_line, //lost a lot of blobs int &outcount //no of real blobs ) { //blobs BLOBNBOX_IT blob_it = row->blob_list (); register int blobindex; /*no along text line */ int losscount; //lost blobs int maxlosscount; //greatest lost blobs /*height stat collection */ STATS heightstat (0, MAXHEIGHT); if (blob_it.empty ()) return 0; //none maxlosscount = 0; losscount = 0; blob_it.mark_cycle_pt (); blobindex = 0; do { blobcoords[blobindex] = box_next_pre_chopped (&blob_it); if (blobcoords[blobindex].height () > lineheight * 0.25) heightstat.add (blobcoords[blobindex].height (), 1); if (blobindex == 0 || blobcoords[blobindex].height () > lineheight * 0.25 || blob_it.cycled_list ()) { blobindex++; /*no of merged blobs */ losscount = 0; } else { if (blobcoords[blobindex].height () < blobcoords[blobindex].width () * oldbl_dot_error_size && blobcoords[blobindex].width () < blobcoords[blobindex].height () * oldbl_dot_error_size) { //counts as dot blobindex++; losscount = 0; } else { losscount++; //lost it if (losscount > maxlosscount) //remember max maxlosscount = losscount; } } } while (!blob_it.cycled_list ()); holed_line = maxlosscount > oldbl_holed_losscount; outcount = blobindex; /*total blobs */ if (heightstat.get_total () > 1) /*guess x-height */ return (int) heightstat.ile (0.25); else return blobcoords[0].height (); } /********************************************************************** * make_first_baseline * * Make the first estimate at a baseline, either by shifting * a supplied previous spline, or by doing a piecewise linear * approximation using all the blobs. **********************************************************************/ void make_first_baseline ( //initial approximation TBOX blobcoords[], /*blob bounding boxes */ int blobcount, /*no of blobcoords */ int xcoords[], /*coords for spline */ int ycoords[], /*approximator */ QSPLINE * spline, /*initial spline */ QSPLINE * baseline, /*output spline */ float jumplimit /*guess half descenders */ ) { int leftedge; /*left edge of line */ int rightedge; /*right edge of line */ int blobindex; /*current blob */ int segment; /*current segment */ float prevy, thisy, nexty; /*3 y coords */ float y1, y2, y3; /*3 smooth blobs */ float maxmax, minmin; /*absolute limits */ int x2 = 0; /*right edge of old y3 */ int ycount; /*no of ycoords in use */ float yturns[SPLINESIZE]; /*y coords of turn pts */ int xturns[SPLINESIZE]; /*xcoords of turn pts */ int xstarts[SPLINESIZE + 1]; int segments; //no of segments ICOORD shift; //shift of spline prevy = 0; /*left edge of row */ leftedge = blobcoords[0].left (); /*right edge of line */ rightedge = blobcoords[blobcount - 1].right (); if (spline == NULL /*no given spline */ || spline->segments < 3 /*or trivial */ /*or too non-overlap */ || spline->xcoords[1] > leftedge + MAXOVERLAP * (rightedge - leftedge) || spline->xcoords[spline->segments - 1] < rightedge - MAXOVERLAP * (rightedge - leftedge)) { if (textord_oldbl_paradef) return; //use default xstarts[0] = blobcoords[0].left () - 1; for (blobindex = 0; blobindex < blobcount; blobindex++) { xcoords[blobindex] = (blobcoords[blobindex].left () + blobcoords[blobindex].right ()) / 2; ycoords[blobindex] = blobcoords[blobindex].bottom (); } xstarts[1] = blobcoords[blobcount - 1].right () + 1; segments = 1; /*no of segments */ /*linear */ *baseline = QSPLINE (xstarts, segments, xcoords, ycoords, blobcount, 1); if (blobcount >= 3) { y1 = y2 = y3 = 0.0f; ycount = 0; segment = 0; /*no of segments */ maxmax = minmin = 0.0f; thisy = ycoords[0] - baseline->y (xcoords[0]); nexty = ycoords[1] - baseline->y (xcoords[1]); for (blobindex = 2; blobindex < blobcount; blobindex++) { prevy = thisy; /*shift ycoords */ thisy = nexty; nexty = ycoords[blobindex] - baseline->y (xcoords[blobindex]); /*middle of smooth y */ if (ABS (thisy - prevy) < jumplimit && ABS (thisy - nexty) < jumplimit) { y1 = y2; /*shift window */ y2 = y3; y3 = thisy; /*middle point */ ycount++; /*local max */ if (ycount >= 3 && ((y1 < y2 && y2 >= y3) /*local min */ || (y1 > y2 && y2 <= y3))) { if (segment < SPLINESIZE - 2) { /*turning pt */ xturns[segment] = x2; yturns[segment] = y2; segment++; /*no of spline segs */ } } if (ycount == 1) { maxmax = minmin = y3;/*initialise limits */ } else { if (y3 > maxmax) maxmax = y3; /*biggest max */ if (y3 < minmin) minmin = y3; /*smallest min */ } /*possible turning pt */ x2 = blobcoords[blobindex - 1].right (); } } jumplimit *= 1.2; /*must be wavy */ if (maxmax - minmin > jumplimit) { ycount = segment; /*no of segments */ for (blobindex = 0, segment = 1; blobindex < ycount; blobindex++) { if (yturns[blobindex] > minmin + jumplimit || yturns[blobindex] < maxmax - jumplimit) { /*significant peak */ if (segment == 1 || yturns[blobindex] > prevy + jumplimit || yturns[blobindex] < prevy - jumplimit) { /*different to previous */ xstarts[segment] = xturns[blobindex]; segment++; prevy = yturns[blobindex]; } /*bigger max */ else if ((prevy > minmin + jumplimit && yturns[blobindex] > prevy) /*smaller min */ || (prevy < maxmax - jumplimit && yturns[blobindex] < prevy)) { xstarts[segment - 1] = xturns[blobindex]; /*improved previous */ prevy = yturns[blobindex]; } } } xstarts[segment] = blobcoords[blobcount - 1].right () + 1; segments = segment; /*no of segments */ /*linear */ *baseline = QSPLINE (xstarts, segments, xcoords, ycoords, blobcount, 1); } } } else { *baseline = *spline; /*copy it */ shift = ICOORD (0, (inT16) (blobcoords[0].bottom () - spline->y (blobcoords[0].right ()))); baseline->move (shift); } } /********************************************************************** * make_holed_baseline * * Make the first estimate at a baseline, either by shifting * a supplied previous spline, or by doing a piecewise linear * approximation using all the blobs. **********************************************************************/ void make_holed_baseline ( //initial approximation TBOX blobcoords[], /*blob bounding boxes */ int blobcount, /*no of blobcoords */ QSPLINE * spline, /*initial spline */ QSPLINE * baseline, /*output spline */ float gradient //of line ) { int leftedge; /*left edge of line */ int rightedge; /*right edge of line */ int blobindex; /*current blob */ float x; //centre of row ICOORD shift; //shift of spline tesseract::DetLineFit lms; // straight baseline inT32 xstarts[2]; //straight line double coeffs[3]; float c; //line parameter /*left edge of row */ leftedge = blobcoords[0].left (); /*right edge of line */ rightedge = blobcoords[blobcount - 1].right(); for (blobindex = 0; blobindex < blobcount; blobindex++) { lms.Add(ICOORD((blobcoords[blobindex].left() + blobcoords[blobindex].right()) / 2, blobcoords[blobindex].bottom())); } lms.ConstrainedFit(gradient, &c); xstarts[0] = leftedge; xstarts[1] = rightedge; coeffs[0] = 0; coeffs[1] = gradient; coeffs[2] = c; *baseline = QSPLINE (1, xstarts, coeffs); if (spline != NULL /*no given spline */ && spline->segments >= 3 /*or trivial */ /*or too non-overlap */ && spline->xcoords[1] <= leftedge + MAXOVERLAP * (rightedge - leftedge) && spline->xcoords[spline->segments - 1] >= rightedge - MAXOVERLAP * (rightedge - leftedge)) { *baseline = *spline; /*copy it */ x = (leftedge + rightedge) / 2.0; shift = ICOORD (0, (inT16) (gradient * x + c - spline->y (x))); baseline->move (shift); } } /********************************************************************** * partition_line * * Partition a row of blobs into different groups of continuous * y position. jumplimit specifies the max allowable limit on a jump * before a new partition is started. * The return value is the biggest partition **********************************************************************/ int partition_line ( //partition blobs TBOX blobcoords[], //bounding boxes int blobcount, /*no of blobs on row */ int *numparts, /*number of partitions */ char partids[], /*partition no of each blob */ int partsizes[], /*no in each partition */ QSPLINE * spline, /*curve to fit to */ float jumplimit, /*allowed delta change */ float ydiffs[] /*diff from spline */ ) { register int blobindex; /*no along text line */ int bestpart; /*best new partition */ int biggestpart; /*part with most members */ float diff; /*difference from line */ int startx; /*index of start blob */ float partdiffs[MAXPARTS]; /*step between parts */ for (bestpart = 0; bestpart < MAXPARTS; bestpart++) partsizes[bestpart] = 0; /*zero them all */ startx = get_ydiffs (blobcoords, blobcount, spline, ydiffs); *numparts = 1; /*1 partition */ bestpart = -1; /*first point */ float drift = 0.0f; float last_delta = 0.0f; for (blobindex = startx; blobindex < blobcount; blobindex++) { /*do each blob in row */ diff = ydiffs[blobindex]; /*diff from line */ if (textord_oldbl_debug) { tprintf ("%d(%d,%d), ", blobindex, blobcoords[blobindex].left (), blobcoords[blobindex].bottom ()); } bestpart = choose_partition(diff, partdiffs, bestpart, jumplimit, &drift, &last_delta, numparts); /*record partition */ partids[blobindex] = bestpart; partsizes[bestpart]++; /*another in it */ } bestpart = -1; /*first point */ drift = 0.0f; last_delta = 0.0f; partsizes[0]--; /*doing 1st pt again */ /*do each blob in row */ for (blobindex = startx; blobindex >= 0; blobindex--) { diff = ydiffs[blobindex]; /*diff from line */ if (textord_oldbl_debug) { tprintf ("%d(%d,%d), ", blobindex, blobcoords[blobindex].left (), blobcoords[blobindex].bottom ()); } bestpart = choose_partition(diff, partdiffs, bestpart, jumplimit, &drift, &last_delta, numparts); /*record partition */ partids[blobindex] = bestpart; partsizes[bestpart]++; /*another in it */ } for (biggestpart = 0, bestpart = 1; bestpart < *numparts; bestpart++) if (partsizes[bestpart] >= partsizes[biggestpart]) biggestpart = bestpart; /*new biggest */ if (textord_oldbl_merge_parts) merge_oldbl_parts(blobcoords, blobcount, partids, partsizes, biggestpart, jumplimit); return biggestpart; /*biggest partition */ } /********************************************************************** * merge_oldbl_parts * * For any adjacent group of blobs in a different part, put them in the * main part if they fit closely to neighbours in the main part. **********************************************************************/ void merge_oldbl_parts ( //partition blobs TBOX blobcoords[], //bounding boxes int blobcount, /*no of blobs on row */ char partids[], /*partition no of each blob */ int partsizes[], /*no in each partition */ int biggestpart, //major partition float jumplimit /*allowed delta change */ ) { BOOL8 found_one; //found a bestpart blob BOOL8 close_one; //found was close enough register int blobindex; /*no along text line */ int prevpart; //previous iteration int runlength; //no in this part float diff; /*difference from line */ int startx; /*index of start blob */ int test_blob; //another index FCOORD coord; //blob coordinate float m, c; //fitted line QLSQ stats; //line stuff prevpart = biggestpart; runlength = 0; startx = 0; for (blobindex = 0; blobindex < blobcount; blobindex++) { if (partids[blobindex] != prevpart) { // tprintf("Partition change at (%d,%d) from %d to %d after run of %d\n", // blobcoords[blobindex].left(),blobcoords[blobindex].bottom(), // prevpart,partids[blobindex],runlength); if (prevpart != biggestpart && runlength > MAXBADRUN) { stats.clear (); for (test_blob = startx; test_blob < blobindex; test_blob++) { coord = FCOORD ((blobcoords[test_blob].left () + blobcoords[test_blob].right ()) / 2.0, blobcoords[test_blob].bottom ()); stats.add (coord.x (), coord.y ()); } stats.fit (1); m = stats.get_b (); c = stats.get_c (); if (textord_oldbl_debug) tprintf ("Fitted line y=%g x + %g\n", m, c); found_one = FALSE; close_one = FALSE; for (test_blob = 1; !found_one && (startx - test_blob >= 0 || blobindex + test_blob <= blobcount); test_blob++) { if (startx - test_blob >= 0 && partids[startx - test_blob] == biggestpart) { found_one = TRUE; coord = FCOORD ((blobcoords[startx - test_blob].left () + blobcoords[startx - test_blob].right ()) / 2.0, blobcoords[startx - test_blob].bottom ()); diff = m * coord.x () + c - coord.y (); if (textord_oldbl_debug) tprintf ("Diff of common blob to suspect part=%g at (%g,%g)\n", diff, coord.x (), coord.y ()); if (diff < jumplimit && -diff < jumplimit) close_one = TRUE; } if (blobindex + test_blob <= blobcount && partids[blobindex + test_blob - 1] == biggestpart) { found_one = TRUE; coord = FCOORD ((blobcoords[blobindex + test_blob - 1]. left () + blobcoords[blobindex + test_blob - 1].right ()) / 2.0, blobcoords[blobindex + test_blob - 1].bottom ()); diff = m * coord.x () + c - coord.y (); if (textord_oldbl_debug) tprintf ("Diff of common blob to suspect part=%g at (%g,%g)\n", diff, coord.x (), coord.y ()); if (diff < jumplimit && -diff < jumplimit) close_one = TRUE; } } if (close_one) { if (textord_oldbl_debug) tprintf ("Merged %d blobs back into part %d from %d starting at (%d,%d)\n", runlength, biggestpart, prevpart, blobcoords[startx].left (), blobcoords[startx].bottom ()); //switch sides partsizes[prevpart] -= runlength; for (test_blob = startx; test_blob < blobindex; test_blob++) partids[test_blob] = biggestpart; } } prevpart = partids[blobindex]; runlength = 1; startx = blobindex; } else runlength++; } } /********************************************************************** * get_ydiffs * * Get the differences between the blobs and the spline, * putting them in ydiffs. The return value is the index * of the blob in the middle of the "best behaved" region **********************************************************************/ int get_ydiffs ( //evaluate differences TBOX blobcoords[], //bounding boxes int blobcount, /*no of blobs */ QSPLINE * spline, /*approximating spline */ float ydiffs[] /*output */ ) { register int blobindex; /*current blob */ int xcentre; /*xcoord */ int lastx; /*last xcentre */ float diffsum; /*sum of diffs */ float diff; /*current difference */ float drift; /*sum of spline steps */ float bestsum; /*smallest diffsum */ int bestindex; /*index of bestsum */ diffsum = 0.0f; bestindex = 0; bestsum = (float) MAX_INT32; drift = 0.0f; lastx = blobcoords[0].left (); /*do each blob in row */ for (blobindex = 0; blobindex < blobcount; blobindex++) { /*centre of blob */ xcentre = (blobcoords[blobindex].left () + blobcoords[blobindex].right ()) >> 1; //step functions in spline drift += spline->step (lastx, xcentre); lastx = xcentre; diff = blobcoords[blobindex].bottom (); diff -= spline->y (xcentre); diff += drift; ydiffs[blobindex] = diff; /*store difference */ if (blobindex > 2) /*remove old one */ diffsum -= ABS (ydiffs[blobindex - 3]); diffsum += ABS (diff); /*add new one */ if (blobindex >= 2 && diffsum < bestsum) { bestsum = diffsum; /*find min sum */ bestindex = blobindex - 1; /*middle of set */ } } return bestindex; } /********************************************************************** * choose_partition * * Choose a partition for the point and return the index. **********************************************************************/ int choose_partition ( //select partition register float diff, /*diff from spline */ float partdiffs[], /*diff on all parts */ int lastpart, /*last assigned partition */ float jumplimit, /*new part threshold */ float* drift, float* lastdelta, int *partcount /*no of partitions */ ) { register int partition; /*partition no */ int bestpart; /*best new partition */ float bestdelta; /*best gap from a part */ float delta; /*diff from part */ if (lastpart < 0) { partdiffs[0] = diff; lastpart = 0; /*first point */ *drift = 0.0f; *lastdelta = 0.0f; } /*adjusted diff from part */ delta = diff - partdiffs[lastpart] - *drift; if (textord_oldbl_debug) { tprintf ("Diff=%.2f, Delta=%.3f, Drift=%.3f, ", diff, delta, *drift); } if (ABS (delta) > jumplimit / 2) { /*delta on part 0 */ bestdelta = diff - partdiffs[0] - *drift; bestpart = 0; /*0 best so far */ for (partition = 1; partition < *partcount; partition++) { delta = diff - partdiffs[partition] - *drift; if (ABS (delta) < ABS (bestdelta)) { bestdelta = delta; bestpart = partition; /*part with nearest jump */ } } delta = bestdelta; /*too far away */ if (ABS (bestdelta) > jumplimit && *partcount < MAXPARTS) { /*and spare part left */ bestpart = (*partcount)++; /*best was new one */ /*start new one */ partdiffs[bestpart] = diff - *drift; delta = 0.0f; } } else { bestpart = lastpart; /*best was last one */ } if (bestpart == lastpart && (ABS (delta - *lastdelta) < jumplimit / 2 || ABS (delta) < jumplimit / 2)) /*smooth the drift */ *drift = (3 * *drift + delta) / 3; *lastdelta = delta; if (textord_oldbl_debug) { tprintf ("P=%d\n", bestpart); } return bestpart; } ///*merge_partitions(partids,partcount,blobcount,bestpart) discards funny looking //partitions and gives all the rest partid 0*/ // //merge_partitions(partids,partcount,blobcount,bestpart) //register char *partids; /*partition numbers*/ //int partcount; /*no of partitions*/ //int blobcount; /*no of blobs*/ //int bestpart; /*best partition*/ //{ // register int blobindex; /*no along text line*/ // int runlength; /*run of same partition*/ // int bestrun; /*biggest runlength*/ // // bestrun=0; /*no runs yet*/ // runlength=1; // for (blobindex=1;blobindexbestrun) // bestrun=runlength; /*find biggest run*/ // runlength=1; /*new run*/ // } // else // { runlength++; // } // } // if (runlength>bestrun) // bestrun=runlength; // // for (blobindex=0;blobindex=blobcount // || partids[blobindex]!=partids[blobindex+1]) // /*loner*/ // && (bestrun>2 || partids[blobindex]!=bestpart)) // { partids[blobindex]=partcount; /*discard loner*/ // } // else if (blobindex+1=blobcount // || partids[blobindex]!=partids[blobindex+2]) // && (bestrun>3 || partids[blobindex]!=bestpart)) // { partids[blobindex]=partcount; /*discard both*/ // partids[blobindex+1]=partcount; // } // } // } // for (blobindex=0;blobindex> 1; ycoords[pointcount++] = blobcoords[blobindex].bottom (); } } return pointcount; /*no of points found */ } /********************************************************************** * segment_spline * * Segment the row at midpoints between maxima and minima of the x,y pairs. * The xstarts of the segments are returned and the number found. **********************************************************************/ int segment_spline ( //make xstarts TBOX blobcoords[], //boundign boxes int blobcount, /*no of blobs in row */ int xcoords[], /*points to work on */ int ycoords[], /*points to work on */ int degree, int pointcount, /*no of points */ int xstarts[] //result ) { register int ptindex; /*no along text line */ register int segment; /*partition no */ int lastmin, lastmax; /*possible turn points */ int turnpoints[SPLINESIZE]; /*good turning points */ int turncount; /*no of turning points */ int max_x; //max specified coord xstarts[0] = xcoords[0] - 1; //leftmost defined pt max_x = xcoords[pointcount - 1] + 1; if (degree < 2) pointcount = 0; turncount = 0; /*no turning points yet */ if (pointcount > 3) { ptindex = 1; lastmax = lastmin = 0; /*start with first one */ while (ptindex < pointcount - 1 && turncount < SPLINESIZE - 1) { /*minimum */ if (ycoords[ptindex - 1] > ycoords[ptindex] && ycoords[ptindex] <= ycoords[ptindex + 1]) { if (ycoords[ptindex] < ycoords[lastmax] - TURNLIMIT) { if (turncount == 0 || turnpoints[turncount - 1] != lastmax) /*new max point */ turnpoints[turncount++] = lastmax; lastmin = ptindex; /*latest minimum */ } else if (ycoords[ptindex] < ycoords[lastmin]) { lastmin = ptindex; /*lower minimum */ } } /*maximum */ if (ycoords[ptindex - 1] < ycoords[ptindex] && ycoords[ptindex] >= ycoords[ptindex + 1]) { if (ycoords[ptindex] > ycoords[lastmin] + TURNLIMIT) { if (turncount == 0 || turnpoints[turncount - 1] != lastmin) /*new min point */ turnpoints[turncount++] = lastmin; lastmax = ptindex; /*latest maximum */ } else if (ycoords[ptindex] > ycoords[lastmax]) { lastmax = ptindex; /*higher maximum */ } } ptindex++; } /*possible global min */ if (ycoords[ptindex] < ycoords[lastmax] - TURNLIMIT && (turncount == 0 || turnpoints[turncount - 1] != lastmax)) { if (turncount < SPLINESIZE - 1) /*2 more turns */ turnpoints[turncount++] = lastmax; if (turncount < SPLINESIZE - 1) turnpoints[turncount++] = ptindex; } else if (ycoords[ptindex] > ycoords[lastmin] + TURNLIMIT /*possible global max */ && (turncount == 0 || turnpoints[turncount - 1] != lastmin)) { if (turncount < SPLINESIZE - 1) /*2 more turns */ turnpoints[turncount++] = lastmin; if (turncount < SPLINESIZE - 1) turnpoints[turncount++] = ptindex; } else if (turncount > 0 && turnpoints[turncount - 1] == lastmin && turncount < SPLINESIZE - 1) { if (ycoords[ptindex] > ycoords[lastmax]) turnpoints[turncount++] = ptindex; else turnpoints[turncount++] = lastmax; } else if (turncount > 0 && turnpoints[turncount - 1] == lastmax && turncount < SPLINESIZE - 1) { if (ycoords[ptindex] < ycoords[lastmin]) turnpoints[turncount++] = ptindex; else turnpoints[turncount++] = lastmin; } } if (textord_oldbl_debug && turncount > 0) tprintf ("First turn is %d at (%d,%d)\n", turnpoints[0], xcoords[turnpoints[0]], ycoords[turnpoints[0]]); for (segment = 1; segment < turncount; segment++) { /*centre y coord */ lastmax = (ycoords[turnpoints[segment - 1]] + ycoords[turnpoints[segment]]) / 2; /* fix alg so that it works with both rising and falling sections */ if (ycoords[turnpoints[segment - 1]] < ycoords[turnpoints[segment]]) /*find rising y centre */ for (ptindex = turnpoints[segment - 1] + 1; ptindex < turnpoints[segment] && ycoords[ptindex + 1] <= lastmax; ptindex++); else /*find falling y centre */ for (ptindex = turnpoints[segment - 1] + 1; ptindex < turnpoints[segment] && ycoords[ptindex + 1] >= lastmax; ptindex++); /*centre x */ xstarts[segment] = (xcoords[ptindex - 1] + xcoords[ptindex] + xcoords[turnpoints[segment - 1]] + xcoords[turnpoints[segment]] + 2) / 4; /*halfway between turns */ if (textord_oldbl_debug) tprintf ("Turn %d is %d at (%d,%d), mid pt is %d@%d, final @%d\n", segment, turnpoints[segment], xcoords[turnpoints[segment]], ycoords[turnpoints[segment]], ptindex - 1, xcoords[ptindex - 1], xstarts[segment]); } xstarts[segment] = max_x; return segment; /*no of splines */ } /********************************************************************** * split_stepped_spline * * Re-segment the spline in cases where there is a big step function. * Return TRUE if any were done. **********************************************************************/ BOOL8 split_stepped_spline ( //make xstarts QSPLINE * baseline, //current shot float jumplimit, //max step fuction int xcoords[], /*points to work on */ int xstarts[], //result int &segments //no of segments ) { BOOL8 doneany; //return value register int segment; /*partition no */ int startindex, centreindex, endindex; float leftcoord, rightcoord; int leftindex, rightindex; float step; //spline step doneany = FALSE; startindex = 0; for (segment = 1; segment < segments - 1; segment++) { step = baseline->step ((xstarts[segment - 1] + xstarts[segment]) / 2.0, (xstarts[segment] + xstarts[segment + 1]) / 2.0); if (step < 0) step = -step; if (step > jumplimit) { while (xcoords[startindex] < xstarts[segment - 1]) startindex++; centreindex = startindex; while (xcoords[centreindex] < xstarts[segment]) centreindex++; endindex = centreindex; while (xcoords[endindex] < xstarts[segment + 1]) endindex++; if (segments >= SPLINESIZE) { if (textord_debug_baselines) tprintf ("Too many segments to resegment spline!!\n"); } else if (endindex - startindex >= textord_spline_medianwin * 3) { while (centreindex - startindex < textord_spline_medianwin * 3 / 2) centreindex++; while (endindex - centreindex < textord_spline_medianwin * 3 / 2) centreindex--; leftindex = (startindex + startindex + centreindex) / 3; rightindex = (centreindex + endindex + endindex) / 3; leftcoord = (xcoords[startindex] * 2 + xcoords[centreindex]) / 3.0; rightcoord = (xcoords[centreindex] + xcoords[endindex] * 2) / 3.0; while (xcoords[leftindex] > leftcoord && leftindex - startindex > textord_spline_medianwin) leftindex--; while (xcoords[leftindex] < leftcoord && centreindex - leftindex > textord_spline_medianwin / 2) leftindex++; if (xcoords[leftindex] - leftcoord > leftcoord - xcoords[leftindex - 1]) leftindex--; while (xcoords[rightindex] > rightcoord && rightindex - centreindex > textord_spline_medianwin / 2) rightindex--; while (xcoords[rightindex] < rightcoord && endindex - rightindex > textord_spline_medianwin) rightindex++; if (xcoords[rightindex] - rightcoord > rightcoord - xcoords[rightindex - 1]) rightindex--; if (textord_debug_baselines) tprintf ("Splitting spline at %d with step %g at (%d,%d)\n", xstarts[segment], baseline-> step ((xstarts[segment - 1] + xstarts[segment]) / 2.0, (xstarts[segment] + xstarts[segment + 1]) / 2.0), (xcoords[leftindex - 1] + xcoords[leftindex]) / 2, (xcoords[rightindex - 1] + xcoords[rightindex]) / 2); insert_spline_point (xstarts, segment, (xcoords[leftindex - 1] + xcoords[leftindex]) / 2, (xcoords[rightindex - 1] + xcoords[rightindex]) / 2, segments); doneany = TRUE; } else if (textord_debug_baselines) { tprintf ("Resegmenting spline failed - insufficient pts (%d,%d,%d,%d)\n", startindex, centreindex, endindex, (inT32) textord_spline_medianwin); } } // else tprintf("Spline step at %d is %g\n", // xstarts[segment], // baseline->step((xstarts[segment-1]+xstarts[segment])/2.0, // (xstarts[segment]+xstarts[segment+1])/2.0)); } return doneany; } /********************************************************************** * insert_spline_point * * Insert a new spline point and shuffle up the others. **********************************************************************/ void insert_spline_point ( //get descenders int xstarts[], //starts to shuffle int segment, //insertion pt int coord1, //coords to add int coord2, int &segments //total segments ) { int index; //for shuffling for (index = segments; index > segment; index--) xstarts[index + 1] = xstarts[index]; segments++; xstarts[segment] = coord1; xstarts[segment + 1] = coord2; } /********************************************************************** * find_lesser_parts * * Average the step from the spline for the other partitions * and find the commonest partition which has a descender. **********************************************************************/ void find_lesser_parts ( //get descenders TO_ROW * row, //row to process TBOX blobcoords[], //bounding boxes int blobcount, /*no of blobs */ char partids[], /*partition of each blob */ int partsizes[], /*size of each part */ int partcount, /*no of partitions */ int bestpart /*biggest partition */ ) { register int blobindex; /*index of blob */ register int partition; /*current partition */ int xcentre; /*centre of blob */ int poscount; /*count of best up step */ int negcount; /*count of best down step */ float partsteps[MAXPARTS]; /*average step to part */ float bestpos; /*best up step */ float bestneg; /*best down step */ int runlength; /*length of bad run */ int biggestrun; /*biggest bad run */ biggestrun = 0; for (partition = 0; partition < partcount; partition++) partsteps[partition] = 0.0; /*zero accumulators */ for (runlength = 0, blobindex = 0; blobindex < blobcount; blobindex++) { xcentre = (blobcoords[blobindex].left () + blobcoords[blobindex].right ()) >> 1; /*in other parts */ if (partids[blobindex] != bestpart) { runlength++; /*run of non bests */ if (runlength > biggestrun) biggestrun = runlength; partsteps[partids[blobindex]] += blobcoords[blobindex].bottom () - row->baseline.y (xcentre); } else runlength = 0; } if (biggestrun > MAXBADRUN) row->xheight = -1.0f; /*failed */ else row->xheight = 1.0f; /*success */ poscount = negcount = 0; bestpos = bestneg = 0.0; /*no step yet */ for (partition = 0; partition < partcount; partition++) { if (partition != bestpart) { //by jetsoft divide by zero possible if (partsizes[partition]==0) partsteps[partition]=0; else partsteps[partition] /= partsizes[partition]; // if (partsteps[partition] >= MINASCRISE && partsizes[partition] > poscount) { /*ascender rise */ bestpos = partsteps[partition]; /*2nd most popular */ poscount = partsizes[partition]; } if (partsteps[partition] <= -MINASCRISE && partsizes[partition] > negcount) { /*ascender rise */ bestneg = partsteps[partition]; /*2nd most popular */ negcount = partsizes[partition]; } } } /*average x-height */ partsteps[bestpart] /= blobcount; row->descdrop = bestneg; } /********************************************************************** * old_first_xheight * * Makes an x-height spline by copying the baseline and shifting it. * It estimates the x-height across the line to use as the shift. * It also finds the ascender height if it can. **********************************************************************/ void old_first_xheight ( //the wiseowl way TO_ROW * row, /*current row */ TBOX blobcoords[], /*blob bounding boxes */ int initialheight, //initial guess int blobcount, /*blobs in blobcoords */ QSPLINE * baseline, /*established */ float jumplimit /*min ascender height */ ) { register int blobindex; /*current blob */ /*height statistics */ STATS heightstat (0, MAXHEIGHT); int height; /*height of blob */ int xcentre; /*centre of blob */ int lineheight; /*approx xheight */ float ascenders; /*ascender sum */ int asccount; /*no of ascenders */ float xsum; /*xheight sum */ int xcount; /*xheight count */ register float diff; /*height difference */ if (blobcount > 1) { for (blobindex = 0; blobindex < blobcount; blobindex++) { xcentre = (blobcoords[blobindex].left () + blobcoords[blobindex].right ()) / 2; /*height of blob */ height = (int) (blobcoords[blobindex].top () - baseline->y (xcentre) + 0.5); if (height > initialheight * oldbl_xhfract && height > textord_min_xheight) heightstat.add (height, 1); } if (heightstat.get_total () > 3) { lineheight = (int) heightstat.ile (0.25); if (lineheight <= 0) lineheight = (int) heightstat.ile (0.5); } else lineheight = initialheight; } else { lineheight = (int) (blobcoords[0].top () - baseline->y ((blobcoords[0].left () + blobcoords[0].right ()) / 2) + 0.5); } xsum = 0.0f; xcount = 0; for (ascenders = 0.0f, asccount = 0, blobindex = 0; blobindex < blobcount; blobindex++) { xcentre = (blobcoords[blobindex].left () + blobcoords[blobindex].right ()) / 2; diff = blobcoords[blobindex].top () - baseline->y (xcentre); /*is it ascender */ if (diff > lineheight + jumplimit) { ascenders += diff; asccount++; /*count ascenders */ } else if (diff > lineheight - jumplimit) { xsum += diff; /*mean xheight */ xcount++; } } if (xcount > 0) xsum /= xcount; /*average xheight */ else xsum = (float) lineheight; /*guess it */ row->xheight *= xsum; if (asccount > 0) row->ascrise = ascenders / asccount - xsum; else row->ascrise = 0.0f; /*had none */ if (row->xheight == 0) row->xheight = -1.0f; } /********************************************************************** * make_first_xheight * * Makes an x-height spline by copying the baseline and shifting it. * It estimates the x-height across the line to use as the shift. * It also finds the ascender height if it can. **********************************************************************/ void make_first_xheight ( //find xheight TO_ROW * row, /*current row */ TBOX blobcoords[], /*blob bounding boxes */ int lineheight, //initial guess int init_lineheight, //block level guess int blobcount, /*blobs in blobcoords */ QSPLINE * baseline, /*established */ float jumplimit /*min ascender height */ ) { STATS heightstat (0, HEIGHTBUCKETS); int lefts[HEIGHTBUCKETS]; int rights[HEIGHTBUCKETS]; int modelist[MODENUM]; int blobindex; int mode_count; //blobs to count in thr int sign_bit; int mode_threshold; const int kBaselineTouch = 2; // This really should change with resolution. const int kGoodStrength = 8; // Strength of baseline-touching heights. const float kMinHeight = 0.25; // Min fraction of lineheight to use. sign_bit = row->xheight > 0 ? 1 : -1; memset(lefts, 0, HEIGHTBUCKETS * sizeof(lefts[0])); memset(rights, 0, HEIGHTBUCKETS * sizeof(rights[0])); mode_count = 0; for (blobindex = 0; blobindex < blobcount; blobindex++) { int xcenter = (blobcoords[blobindex].left () + blobcoords[blobindex].right ()) / 2; float base = baseline->y(xcenter); float bottomdiff = fabs(base - blobcoords[blobindex].bottom()); int strength = textord_ocropus_mode && bottomdiff <= kBaselineTouch ? kGoodStrength : 1; int height = static_cast(blobcoords[blobindex].top () - base + 0.5); if (blobcoords[blobindex].height () > init_lineheight * kMinHeight) { if (height > lineheight * oldbl_xhfract && height > textord_min_xheight) { heightstat.add (height, strength); if (height < HEIGHTBUCKETS) { if (xcenter > rights[height]) rights[height] = xcenter; if (xcenter > 0 && (lefts[height] == 0 || xcenter < lefts[height])) lefts[height] = xcenter; } } mode_count += strength; } } mode_threshold = (int) (blobcount * 0.1); if (oldbl_dot_error_size > 1 || oldbl_xhfix) mode_threshold = (int) (mode_count * 0.1); if (textord_oldbl_debug) { tprintf ("blobcount=%d, mode_count=%d, mode_t=%d\n", blobcount, mode_count, mode_threshold); } find_top_modes(&heightstat, HEIGHTBUCKETS, modelist, MODENUM); if (textord_oldbl_debug) { for (blobindex = 0; blobindex < MODENUM; blobindex++) tprintf ("mode[%d]=%d ", blobindex, modelist[blobindex]); tprintf ("\n"); } pick_x_height(row, modelist, lefts, rights, &heightstat, mode_threshold); if (textord_oldbl_debug) tprintf ("Output xheight=%g\n", row->xheight); if (row->xheight < 0 && textord_oldbl_debug) tprintf ("warning: Row Line height < 0; %4.2f\n", row->xheight); if (sign_bit < 0) row->xheight = -row->xheight; } /********************************************************************** * find_top_modes * * Fill the input array with the indices of the top ten modes of the * input distribution. **********************************************************************/ const int kMinModeFactorOcropus = 32; const int kMinModeFactor = 12; void find_top_modes ( //get modes STATS * stats, //stats to hack int statnum, //no of piles int modelist[], int modenum //no of modes to get ) { int mode_count; int last_i = 0; int last_max = MAX_INT32; int i; int mode; int total_max = 0; int mode_factor = textord_ocropus_mode ? kMinModeFactorOcropus : kMinModeFactor; for (mode_count = 0; mode_count < modenum; mode_count++) { mode = 0; for (i = 0; i < statnum; i++) { if (stats->pile_count (i) > stats->pile_count (mode)) { if ((stats->pile_count (i) < last_max) || ((stats->pile_count (i) == last_max) && (i > last_i))) { mode = i; } } } last_i = mode; last_max = stats->pile_count (last_i); total_max += last_max; if (last_max <= total_max / mode_factor) mode = 0; modelist[mode_count] = mode; } } /********************************************************************** * pick_x_height * * Choose based on the height modes the best x height value. **********************************************************************/ void pick_x_height(TO_ROW * row, //row to do int modelist[], int lefts[], int rights[], STATS * heightstat, int mode_threshold) { int x; int y; int z; float ratio; int found_one_bigger = FALSE; int best_x_height = 0; int best_asc = 0; int num_in_best; for (x = 0; x < MODENUM; x++) { for (y = 0; y < MODENUM; y++) { /* Check for two modes */ if (modelist[x] && modelist[y] && heightstat->pile_count (modelist[x]) > mode_threshold && (!textord_ocropus_mode || MIN(rights[modelist[x]], rights[modelist[y]]) > MAX(lefts[modelist[x]], lefts[modelist[y]]))) { ratio = (float) modelist[y] / (float) modelist[x]; if (1.2 < ratio && ratio < 1.8) { /* Two modes found */ best_x_height = modelist[x]; num_in_best = heightstat->pile_count (modelist[x]); /* Try to get one higher */ do { found_one_bigger = FALSE; for (z = 0; z < MODENUM; z++) { if (modelist[z] == best_x_height + 1 && (!textord_ocropus_mode || MIN(rights[modelist[x]], rights[modelist[y]]) > MAX(lefts[modelist[x]], lefts[modelist[y]]))) { ratio = (float) modelist[y] / (float) modelist[z]; if ((1.2 < ratio && ratio < 1.8) && /* Should be half of best */ heightstat->pile_count (modelist[z]) > num_in_best * 0.5) { best_x_height++; found_one_bigger = TRUE; break; } } } } while (found_one_bigger); /* try to get a higher ascender */ best_asc = modelist[y]; num_in_best = heightstat->pile_count (modelist[y]); /* Try to get one higher */ do { found_one_bigger = FALSE; for (z = 0; z < MODENUM; z++) { if (modelist[z] > best_asc && (!textord_ocropus_mode || MIN(rights[modelist[x]], rights[modelist[y]]) > MAX(lefts[modelist[x]], lefts[modelist[y]]))) { ratio = (float) modelist[z] / (float) best_x_height; if ((1.2 < ratio && ratio < 1.8) && /* Should be half of best */ heightstat->pile_count (modelist[z]) > num_in_best * 0.5) { best_asc = modelist[z]; found_one_bigger = TRUE; break; } } } } while (found_one_bigger); row->xheight = (float) best_x_height; row->ascrise = (float) best_asc - best_x_height; return; } } } } best_x_height = modelist[0]; /* Single Mode found */ num_in_best = heightstat->pile_count (best_x_height); do { /* Try to get one higher */ found_one_bigger = FALSE; for (z = 1; z < MODENUM; z++) { /* Should be half of best */ if ((modelist[z] == best_x_height + 1) && (heightstat->pile_count (modelist[z]) > num_in_best * 0.5)) { best_x_height++; found_one_bigger = TRUE; break; } } } while (found_one_bigger); row->ascrise = 0.0f; row->xheight = (float) best_x_height; if (row->xheight == 0) row->xheight = -1.0f; }