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64f9190575
All of them were found by codespell. Signed-off-by: Stefan Weil <sw@weilnetz.de>
553 lines
23 KiB
C++
553 lines
23 KiB
C++
///////////////////////////////////////////////////////////////////////
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// File: alignedblob.cpp
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// Description: Subclass of BBGrid to find vertically aligned blobs.
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// Author: Ray Smith
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// Created: Fri Mar 21 15:03:01 PST 2008
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//
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// (C) Copyright 2008, Google Inc.
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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// http://www.apache.org/licenses/LICENSE-2.0
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//
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///////////////////////////////////////////////////////////////////////
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#ifdef HAVE_CONFIG_H
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#include "config_auto.h"
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#endif
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#include "alignedblob.h"
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#include "ndminx.h"
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INT_VAR(textord_debug_tabfind, 0, "Debug tab finding");
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INT_VAR(textord_debug_bugs, 0, "Turn on output related to bugs in tab finding");
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INT_VAR(textord_testregion_left, -1, "Left edge of debug reporting rectangle");
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INT_VAR(textord_testregion_top, -1, "Top edge of debug reporting rectangle");
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INT_VAR(textord_testregion_right, MAX_INT32, "Right edge of debug rectangle");
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INT_VAR(textord_testregion_bottom, MAX_INT32, "Bottom edge of debug rectangle");
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BOOL_VAR(textord_debug_images, false, "Use greyed image background for debug");
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BOOL_VAR(textord_debug_printable, false, "Make debug windows printable");
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namespace tesseract {
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// Fraction of resolution used as alignment tolerance for aligned tabs.
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const double kAlignedFraction = 0.03125;
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// Fraction of resolution used as alignment tolerance for ragged tabs.
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const double kRaggedFraction = 2.5;
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// Fraction of height used as a minimum gutter gap for aligned blobs.
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const double kAlignedGapFraction = 0.75;
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// Fraction of height used as a minimum gutter gap for ragged tabs.
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const double kRaggedGapFraction = 1.0;
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// Constant number of pixels used as alignment tolerance for line finding.
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const int kVLineAlignment = 3;
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// Constant number of pixels used as gutter gap tolerance for line finding.
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const int kVLineGutter = 1;
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// Constant number of pixels used as the search size for line finding.
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const int kVLineSearchSize = 150;
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// Min number of points to accept for a ragged tab stop.
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const int kMinRaggedTabs = 5;
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// Min number of points to accept for an aligned tab stop.
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const int kMinAlignedTabs = 4;
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// Constant number of pixels minimum height of a vertical line.
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const int kVLineMinLength = 500;
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// Minimum gradient for a vertical tab vector. Used to prune away junk
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// tab vectors with what would be a ridiculously large skew angle.
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// Value corresponds to tan(90 - max allowed skew angle)
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const double kMinTabGradient = 4.0;
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// Tolerance to skew on top of current estimate of skew. Divide x or y length
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// by kMaxSkewFactor to get the y or x skew distance.
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// If the angle is small, the angle in degrees is roughly 60/kMaxSkewFactor.
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const int kMaxSkewFactor = 15;
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// Constant part of textord_debug_pix_.
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const char* kTextordDebugPix = "psdebug_pix";
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// Name of image file to use if textord_debug_images is true.
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STRING AlignedBlob::textord_debug_pix_ = kTextordDebugPix;
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// Index to image file to use if textord_debug_images is true.
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int AlignedBlob::debug_pix_index_ = 0;
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// Increment the serial number counter and set the string to use
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// for a filename if textord_debug_images is true.
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void AlignedBlob::IncrementDebugPix() {
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++debug_pix_index_;
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textord_debug_pix_ = kTextordDebugPix;
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char numbuf[32];
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snprintf(numbuf, sizeof(numbuf), "%d", debug_pix_index_);
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textord_debug_pix_ += numbuf;
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textord_debug_pix_ += ".pix";
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}
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// Constructor to set the parameters for finding aligned and ragged tabs.
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// Vertical_x and vertical_y are the current estimates of the true vertical
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// direction (up) in the image. Height is the height of the starter blob.
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// v_gap_multiple is the multiple of height that will be used as a limit
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// on vertical gap before giving up and calling the line ended.
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// resolution is the original image resolution, and align0 indicates the
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// type of tab stop to be found.
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AlignedBlobParams::AlignedBlobParams(int vertical_x, int vertical_y,
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int height, int v_gap_multiple,
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int min_gutter_width,
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int resolution, TabAlignment align0)
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: right_tab(align0 == TA_RIGHT_RAGGED || align0 == TA_RIGHT_ALIGNED),
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ragged(align0 == TA_LEFT_RAGGED || align0 == TA_RIGHT_RAGGED),
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alignment(align0),
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confirmed_type(TT_CONFIRMED),
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min_length(0) {
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// Set the tolerances according to the type of line sought.
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// For tab search, these are based on the image resolution for most, or
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// the height of the starting blob for the maximum vertical gap.
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max_v_gap = height * v_gap_multiple;
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if (ragged) {
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// In the case of a ragged edge, we are much more generous with the
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// inside alignment fraction, but also require a much bigger gutter.
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gutter_fraction = kRaggedGapFraction;
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if (alignment == TA_RIGHT_RAGGED) {
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l_align_tolerance = static_cast<int>(resolution * kRaggedFraction + 0.5);
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r_align_tolerance = static_cast<int>(resolution * kAlignedFraction + 0.5);
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} else {
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l_align_tolerance = static_cast<int>(resolution * kAlignedFraction + 0.5);
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r_align_tolerance = static_cast<int>(resolution * kRaggedFraction + 0.5);
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}
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min_points = kMinRaggedTabs;
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} else {
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gutter_fraction = kAlignedGapFraction;
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l_align_tolerance = static_cast<int>(resolution * kAlignedFraction + 0.5);
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r_align_tolerance = static_cast<int>(resolution * kAlignedFraction + 0.5);
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min_points = kMinAlignedTabs;
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}
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min_gutter = static_cast<int>(height * gutter_fraction + 0.5);
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if (min_gutter < min_gutter_width)
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min_gutter = min_gutter_width;
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// Fit the vertical vector into an ICOORD, which is 16 bit.
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set_vertical(vertical_x, vertical_y);
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}
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// Constructor to set the parameters for finding vertical lines.
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// Vertical_x and vertical_y are the current estimates of the true vertical
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// direction (up) in the image. Width is the width of the starter blob.
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AlignedBlobParams::AlignedBlobParams(int vertical_x, int vertical_y,
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int width)
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: gutter_fraction(0.0),
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right_tab(false),
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ragged(false),
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alignment(TA_SEPARATOR),
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confirmed_type(TT_VLINE),
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max_v_gap(kVLineSearchSize),
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min_gutter(kVLineGutter),
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min_points(1),
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min_length(kVLineMinLength) {
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// Compute threshold for left and right alignment.
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l_align_tolerance = MAX(kVLineAlignment, width);
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r_align_tolerance = MAX(kVLineAlignment, width);
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// Fit the vertical vector into an ICOORD, which is 16 bit.
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set_vertical(vertical_x, vertical_y);
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}
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// Fit the vertical vector into an ICOORD, which is 16 bit.
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void AlignedBlobParams::set_vertical(int vertical_x, int vertical_y) {
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int factor = 1;
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if (vertical_y > MAX_INT16)
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factor = vertical_y / MAX_INT16 + 1;
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vertical.set_x(vertical_x / factor);
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vertical.set_y(vertical_y / factor);
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}
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AlignedBlob::AlignedBlob(int gridsize,
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const ICOORD& bleft, const ICOORD& tright)
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: BlobGrid(gridsize, bleft, tright) {
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}
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AlignedBlob::~AlignedBlob() {
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}
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// Return true if the given coordinates are within the test rectangle
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// and the debug level is at least the given detail level.
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bool AlignedBlob::WithinTestRegion(int detail_level, int x, int y) {
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if (textord_debug_tabfind < detail_level)
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return false;
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return x >= textord_testregion_left && x <= textord_testregion_right &&
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y <= textord_testregion_top && y >= textord_testregion_bottom;
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}
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// Display the tab codes of the BLOBNBOXes in this grid.
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ScrollView* AlignedBlob::DisplayTabs(const char* window_name,
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ScrollView* tab_win) {
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#ifndef GRAPHICS_DISABLED
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if (tab_win == NULL)
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tab_win = MakeWindow(0, 50, window_name);
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// For every tab in the grid, display it.
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GridSearch<BLOBNBOX, BLOBNBOX_CLIST, BLOBNBOX_C_IT> gsearch(this);
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gsearch.StartFullSearch();
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BLOBNBOX* bbox;
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while ((bbox = gsearch.NextFullSearch()) != NULL) {
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TBOX box = bbox->bounding_box();
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int left_x = box.left();
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int right_x = box.right();
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int top_y = box.top();
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int bottom_y = box.bottom();
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TabType tabtype = bbox->left_tab_type();
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if (tabtype != TT_NONE) {
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if (tabtype == TT_MAYBE_ALIGNED)
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tab_win->Pen(ScrollView::BLUE);
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else if (tabtype == TT_MAYBE_RAGGED)
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tab_win->Pen(ScrollView::YELLOW);
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else if (tabtype == TT_CONFIRMED)
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tab_win->Pen(ScrollView::GREEN);
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else
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tab_win->Pen(ScrollView::GREY);
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tab_win->Line(left_x, top_y, left_x, bottom_y);
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}
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tabtype = bbox->right_tab_type();
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if (tabtype != TT_NONE) {
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if (tabtype == TT_MAYBE_ALIGNED)
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tab_win->Pen(ScrollView::MAGENTA);
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else if (tabtype == TT_MAYBE_RAGGED)
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tab_win->Pen(ScrollView::ORANGE);
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else if (tabtype == TT_CONFIRMED)
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tab_win->Pen(ScrollView::RED);
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else
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tab_win->Pen(ScrollView::GREY);
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tab_win->Line(right_x, top_y, right_x, bottom_y);
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}
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}
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tab_win->Update();
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#endif
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return tab_win;
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}
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// Helper returns true if the total number of line_crossings of all the blobs
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// in the list is at least 2.
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static bool AtLeast2LineCrossings(BLOBNBOX_CLIST* blobs) {
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BLOBNBOX_C_IT it(blobs);
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int total_crossings = 0;
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for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
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total_crossings += it.data()->line_crossings();
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}
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return total_crossings >= 2;
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}
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// Finds a vector corresponding to a set of vertically aligned blob edges
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// running through the given box. The type of vector returned and the
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// search parameters are determined by the AlignedBlobParams.
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// vertical_x and y are updated with an estimate of the real
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// vertical direction. (skew finding.)
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// Returns NULL if no decent vector can be found.
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TabVector* AlignedBlob::FindVerticalAlignment(AlignedBlobParams align_params,
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BLOBNBOX* bbox,
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int* vertical_x,
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int* vertical_y) {
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int ext_start_y, ext_end_y;
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BLOBNBOX_CLIST good_points;
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// Search up and then down from the starting bbox.
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TBOX box = bbox->bounding_box();
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bool debug = WithinTestRegion(2, box.left(), box.bottom());
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int pt_count = AlignTabs(align_params, false, bbox, &good_points, &ext_end_y);
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pt_count += AlignTabs(align_params, true, bbox, &good_points, &ext_start_y);
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BLOBNBOX_C_IT it(&good_points);
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it.move_to_last();
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box = it.data()->bounding_box();
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int end_y = box.top();
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int end_x = align_params.right_tab ? box.right() : box.left();
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it.move_to_first();
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box = it.data()->bounding_box();
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int start_x = align_params.right_tab ? box.right() : box.left();
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int start_y = box.bottom();
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// Acceptable tab vectors must have a mininum number of points,
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// have a minimum acceptable length, and have a minimum gradient.
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// The gradient corresponds to the skew angle.
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// Ragged tabs don't need to satisfy the gradient condition, as they
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// will always end up parallel to the vertical direction.
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bool at_least_2_crossings = AtLeast2LineCrossings(&good_points);
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if ((pt_count >= align_params.min_points &&
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end_y - start_y >= align_params.min_length &&
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(align_params.ragged ||
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end_y - start_y >= abs(end_x - start_x) * kMinTabGradient)) ||
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at_least_2_crossings) {
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int confirmed_points = 0;
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// Count existing confirmed points to see if vector is acceptable.
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for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
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bbox = it.data();
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if (align_params.right_tab) {
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if (bbox->right_tab_type() == align_params.confirmed_type)
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++confirmed_points;
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} else {
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if (bbox->left_tab_type() == align_params.confirmed_type)
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++confirmed_points;
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}
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}
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// Ragged vectors are not allowed to use too many already used points.
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if (!align_params.ragged ||
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confirmed_points + confirmed_points < pt_count) {
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const TBOX& box = bbox->bounding_box();
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if (debug) {
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tprintf("Confirming tab vector of %d pts starting at %d,%d\n",
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pt_count, box.left(), box.bottom());
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}
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// Flag all the aligned neighbours as confirmed .
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for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
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bbox = it.data();
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if (align_params.right_tab) {
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bbox->set_right_tab_type(align_params.confirmed_type);
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} else {
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bbox->set_left_tab_type(align_params.confirmed_type);
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}
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if (debug) {
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bbox->bounding_box().print();
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}
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}
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// Now make the vector and return it.
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TabVector* result = TabVector::FitVector(align_params.alignment,
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align_params.vertical,
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ext_start_y, ext_end_y,
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&good_points,
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vertical_x, vertical_y);
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result->set_intersects_other_lines(at_least_2_crossings);
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if (debug) {
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tprintf("Box was %d, %d\n", box.left(), box.bottom());
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result->Print("After fitting");
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}
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return result;
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} else if (debug) {
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tprintf("Ragged tab used too many used points: %d out of %d\n",
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confirmed_points, pt_count);
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}
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} else if (debug) {
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tprintf("Tab vector failed basic tests: pt count %d vs min %d, "
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"length %d vs min %d, min grad %g\n",
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pt_count, align_params.min_points, end_y - start_y,
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align_params.min_length, abs(end_x - start_x) * kMinTabGradient);
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}
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return NULL;
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}
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// Find a set of blobs that are aligned in the given vertical
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// direction with the given blob. Returns a list of aligned
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// blobs and the number in the list.
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// For other parameters see FindAlignedBlob below.
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int AlignedBlob::AlignTabs(const AlignedBlobParams& params,
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bool top_to_bottom, BLOBNBOX* bbox,
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BLOBNBOX_CLIST* good_points, int* end_y) {
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int ptcount = 0;
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BLOBNBOX_C_IT it(good_points);
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TBOX box = bbox->bounding_box();
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bool debug = WithinTestRegion(2, box.left(), box.bottom());
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if (debug) {
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tprintf("Starting alignment run at blob:");
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box.print();
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}
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int x_start = params.right_tab ? box.right() : box.left();
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while (bbox != NULL) {
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// Add the blob to the list if the appropriate side is a tab candidate,
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// or if we are working on a ragged tab.
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TabType type = params.right_tab ? bbox->right_tab_type()
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: bbox->left_tab_type();
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if (((type != TT_NONE && type != TT_MAYBE_RAGGED) || params.ragged) &&
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(it.empty() || it.data() != bbox)) {
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if (top_to_bottom)
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it.add_before_then_move(bbox);
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else
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it.add_after_then_move(bbox);
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++ptcount;
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}
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// Find the next blob that is aligned with the current one.
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// FindAlignedBlob guarantees that forward progress will be made in the
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// top_to_bottom direction, and therefore eventually it will return NULL,
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// making this while (bbox != NULL) loop safe.
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bbox = FindAlignedBlob(params, top_to_bottom, bbox, x_start, end_y);
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if (bbox != NULL) {
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box = bbox->bounding_box();
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if (!params.ragged)
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x_start = params.right_tab ? box.right() : box.left();
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}
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}
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if (debug) {
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tprintf("Alignment run ended with %d pts at blob:", ptcount);
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box.print();
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}
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return ptcount;
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}
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// Search vertically for a blob that is aligned with the input bbox.
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// The search parameters are determined by AlignedBlobParams.
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// top_to_bottom tells whether to search down or up.
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// The return value is NULL if nothing was found in the search box
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// or if a blob was found in the gutter. On a NULL return, end_y
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// is set to the edge of the search box or the leading edge of the
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// gutter blob if one was found.
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BLOBNBOX* AlignedBlob::FindAlignedBlob(const AlignedBlobParams& p,
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bool top_to_bottom, BLOBNBOX* bbox,
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int x_start, int* end_y) {
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TBOX box = bbox->bounding_box();
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// If there are separator lines, get the column edges.
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int left_column_edge = bbox->left_rule();
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int right_column_edge = bbox->right_rule();
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// start_y is used to guarantee that forward progress is made and the
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// search does not go into an infinite loop. New blobs must extend the
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// line beyond start_y.
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int start_y = top_to_bottom ? box.bottom() : box.top();
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if (WithinTestRegion(2, x_start, start_y)) {
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tprintf("Column edges for blob at (%d,%d)->(%d,%d) are [%d, %d]\n",
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box.left(), box.top(), box.right(), box.bottom(),
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left_column_edge, right_column_edge);
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}
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// Compute skew tolerance.
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int skew_tolerance = p.max_v_gap / kMaxSkewFactor;
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// Calculate xmin and xmax of the search box so that it contains
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// all possibly relevant boxes up to p.max_v_gap above or below accoording
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// to top_to_bottom.
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// Start with a notion of vertical with the current estimate.
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int x2 = (p.max_v_gap * p.vertical.x() + p.vertical.y()/2) / p.vertical.y();
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if (top_to_bottom) {
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x2 = x_start - x2;
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*end_y = start_y - p.max_v_gap;
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} else {
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x2 = x_start + x2;
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*end_y = start_y + p.max_v_gap;
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}
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// Expand the box by an additional skew tolerance
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int xmin = MIN(x_start, x2) - skew_tolerance;
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int xmax = MAX(x_start, x2) + skew_tolerance;
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// Now add direction-specific tolerances.
|
|
if (p.right_tab) {
|
|
xmax += p.min_gutter;
|
|
xmin -= p.l_align_tolerance;
|
|
} else {
|
|
xmax += p.r_align_tolerance;
|
|
xmin -= p.min_gutter;
|
|
}
|
|
// Setup a vertical search for an aligned blob.
|
|
GridSearch<BLOBNBOX, BLOBNBOX_CLIST, BLOBNBOX_C_IT> vsearch(this);
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("Starting %s %s search at %d-%d,%d, search_size=%d, gutter=%d\n",
|
|
p.ragged ? "Ragged" : "Aligned", p.right_tab ? "Right" : "Left",
|
|
xmin, xmax, start_y, p.max_v_gap, p.min_gutter);
|
|
vsearch.StartVerticalSearch(xmin, xmax, start_y);
|
|
// result stores the best real return value.
|
|
BLOBNBOX* result = NULL;
|
|
// The backup_result is not a tab candidate and can be used if no
|
|
// real tab candidate result is found.
|
|
BLOBNBOX* backup_result = NULL;
|
|
// neighbour is the blob that is currently being investigated.
|
|
BLOBNBOX* neighbour = NULL;
|
|
while ((neighbour = vsearch.NextVerticalSearch(top_to_bottom)) != NULL) {
|
|
if (neighbour == bbox)
|
|
continue;
|
|
TBOX nbox = neighbour->bounding_box();
|
|
int n_y = (nbox.top() + nbox.bottom()) / 2;
|
|
if ((!top_to_bottom && n_y > start_y + p.max_v_gap) ||
|
|
(top_to_bottom && n_y < start_y - p.max_v_gap)) {
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("Neighbour too far at (%d,%d)->(%d,%d)\n",
|
|
nbox.left(), nbox.bottom(), nbox.right(), nbox.top());
|
|
break; // Gone far enough.
|
|
}
|
|
// It is CRITICAL to ensure that forward progress is made, (strictly
|
|
// in/decreasing n_y) or the caller could loop infinitely, while
|
|
// waiting for a sequence of blobs in a line to end.
|
|
// NextVerticalSearch alone does not guarantee this, as there may be
|
|
// more than one blob in a grid cell. See comment in AlignTabs.
|
|
if ((n_y < start_y) != top_to_bottom || nbox.y_overlap(box))
|
|
continue; // Only look in the required direction.
|
|
if (result != NULL && result->bounding_box().y_gap(nbox) > gridsize())
|
|
return result; // This result is clear.
|
|
if (backup_result != NULL && p.ragged && result == NULL &&
|
|
backup_result->bounding_box().y_gap(nbox) > gridsize())
|
|
return backup_result; // This result is clear.
|
|
|
|
// If the neighbouring blob is the wrong side of a separator line, then it
|
|
// "doesn't exist" as far as we are concerned.
|
|
int x_at_n_y = x_start + (n_y - start_y) * p.vertical.x() / p.vertical.y();
|
|
if (x_at_n_y < neighbour->left_crossing_rule() ||
|
|
x_at_n_y > neighbour->right_crossing_rule())
|
|
continue; // Separator line in the way.
|
|
int n_left = nbox.left();
|
|
int n_right = nbox.right();
|
|
int n_x = p.right_tab ? n_right : n_left;
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("neighbour at (%d,%d)->(%d,%d), n_x=%d, n_y=%d, xatn=%d\n",
|
|
nbox.left(), nbox.bottom(), nbox.right(), nbox.top(),
|
|
n_x, n_y, x_at_n_y);
|
|
if (p.right_tab &&
|
|
n_left < x_at_n_y + p.min_gutter &&
|
|
n_right > x_at_n_y + p.r_align_tolerance &&
|
|
(p.ragged || n_left < x_at_n_y + p.gutter_fraction * nbox.height())) {
|
|
// In the gutter so end of line.
|
|
if (bbox->right_tab_type() >= TT_MAYBE_ALIGNED)
|
|
bbox->set_right_tab_type(TT_DELETED);
|
|
*end_y = top_to_bottom ? nbox.top() : nbox.bottom();
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("gutter\n");
|
|
return NULL;
|
|
}
|
|
if (!p.right_tab &&
|
|
n_left < x_at_n_y - p.l_align_tolerance &&
|
|
n_right > x_at_n_y - p.min_gutter &&
|
|
(p.ragged || n_right > x_at_n_y - p.gutter_fraction * nbox.height())) {
|
|
// In the gutter so end of line.
|
|
if (bbox->left_tab_type() >= TT_MAYBE_ALIGNED)
|
|
bbox->set_left_tab_type(TT_DELETED);
|
|
*end_y = top_to_bottom ? nbox.top() : nbox.bottom();
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("gutter\n");
|
|
return NULL;
|
|
}
|
|
if ((p.right_tab && neighbour->leader_on_right()) ||
|
|
(!p.right_tab && neighbour->leader_on_left()))
|
|
continue; // Neighbours of leaders are not allowed to be used.
|
|
if (n_x <= x_at_n_y + p.r_align_tolerance &&
|
|
n_x >= x_at_n_y - p.l_align_tolerance) {
|
|
// Aligned so keep it. If it is a marked tab save it as result,
|
|
// otherwise keep it as backup_result to return in case of later failure.
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("aligned, seeking%d, l=%d, r=%d\n",
|
|
p.right_tab, neighbour->left_tab_type(),
|
|
neighbour->right_tab_type());
|
|
TabType n_type = p.right_tab ? neighbour->right_tab_type()
|
|
: neighbour->left_tab_type();
|
|
if (n_type != TT_NONE && (p.ragged || n_type != TT_MAYBE_RAGGED)) {
|
|
if (result == NULL) {
|
|
result = neighbour;
|
|
} else {
|
|
// Keep the closest neighbour by Euclidean distance.
|
|
// This prevents it from picking a tab blob in another column.
|
|
const TBOX& old_box = result->bounding_box();
|
|
int x_diff = p.right_tab ? old_box.right() : old_box.left();
|
|
x_diff -= x_at_n_y;
|
|
int y_diff = (old_box.top() + old_box.bottom()) / 2 - start_y;
|
|
int old_dist = x_diff * x_diff + y_diff * y_diff;
|
|
x_diff = n_x - x_at_n_y;
|
|
y_diff = n_y - start_y;
|
|
int new_dist = x_diff * x_diff + y_diff * y_diff;
|
|
if (new_dist < old_dist)
|
|
result = neighbour;
|
|
}
|
|
} else if (backup_result == NULL) {
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("Backup\n");
|
|
backup_result = neighbour;
|
|
} else {
|
|
TBOX backup_box = backup_result->bounding_box();
|
|
if ((p.right_tab && backup_box.right() < nbox.right()) ||
|
|
(!p.right_tab && backup_box.left() > nbox.left())) {
|
|
if (WithinTestRegion(2, x_start, start_y))
|
|
tprintf("Better backup\n");
|
|
backup_result = neighbour;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return result != NULL ? result : backup_result;
|
|
}
|
|
|
|
} // namespace tesseract.
|
|
|