tesseract/ccstruct/blobbox.h
Ray Smith 0e868ef377 Major change to improve layout analysis for heavily diacritic languages:
Tha, Vie, Kan, Tel etc.
There is a new overlap detector that detects when diacritics
cause a big increase in textline overlap. In such cases, diacritics from
overlap regions are kept separate from layout analysis completely, allowing
textline formation to happen without them. The diacritics are then assigned
to 0, 1 or 2 close words at the end of layout analysis, using and modifying
an old noise detection data path.
The stored diacritics are used or not during recognition according to the
character classifier's liking for them.
2015-05-12 16:47:02 -07:00

847 lines
30 KiB
C++

/**********************************************************************
* File: blobbox.h (Formerly blobnbox.h)
* Description: Code for the textord blob class.
* Author: Ray Smith
* Created: Thu Jul 30 09:08:51 BST 1992
*
* (C) Copyright 1992, 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.
*
**********************************************************************/
#ifndef BLOBBOX_H
#define BLOBBOX_H
#include "clst.h"
#include "elst2.h"
#include "werd.h"
#include "ocrblock.h"
#include "statistc.h"
enum PITCH_TYPE
{
PITCH_DUNNO, // insufficient data
PITCH_DEF_FIXED, // definitely fixed
PITCH_MAYBE_FIXED, // could be
PITCH_DEF_PROP,
PITCH_MAYBE_PROP,
PITCH_CORR_FIXED,
PITCH_CORR_PROP
};
// The possible tab-stop types of each side of a BLOBNBOX.
// The ordering is important, as it is used for deleting dead-ends in the
// search. ALIGNED, CONFIRMED and VLINE should remain greater than the
// non-aligned, unset, or deleted members.
enum TabType {
TT_NONE, // Not a tab.
TT_DELETED, // Not a tab after detailed analysis.
TT_MAYBE_RAGGED, // Initial designation of a tab-stop candidate.
TT_MAYBE_ALIGNED, // Initial designation of a tab-stop candidate.
TT_CONFIRMED, // Aligned with neighbours.
TT_VLINE // Detected as a vertical line.
};
// The possible region types of a BLOBNBOX.
// Note: keep all the text types > BRT_UNKNOWN and all the image types less.
// Keep in sync with kBlobTypes in colpartition.cpp and BoxColor, and the
// *Type static functions below.
enum BlobRegionType {
BRT_NOISE, // Neither text nor image.
BRT_HLINE, // Horizontal separator line.
BRT_VLINE, // Vertical separator line.
BRT_RECTIMAGE, // Rectangular image.
BRT_POLYIMAGE, // Non-rectangular image.
BRT_UNKNOWN, // Not determined yet.
BRT_VERT_TEXT, // Vertical alignment, not necessarily vertically oriented.
BRT_TEXT, // Convincing text.
BRT_COUNT // Number of possibilities.
};
// enum for elements of arrays that refer to neighbours.
// NOTE: keep in this order, so ^2 can be used to flip direction.
enum BlobNeighbourDir {
BND_LEFT,
BND_BELOW,
BND_RIGHT,
BND_ABOVE,
BND_COUNT
};
// enum for special type of text characters, such as math symbol or italic.
enum BlobSpecialTextType {
BSTT_NONE, // No special.
BSTT_ITALIC, // Italic style.
BSTT_DIGIT, // Digit symbols.
BSTT_MATH, // Mathmatical symobls (not including digit).
BSTT_UNCLEAR, // Characters with low recognition rate.
BSTT_SKIP, // Characters that we skip labeling (usually too small).
BSTT_COUNT
};
inline BlobNeighbourDir DirOtherWay(BlobNeighbourDir dir) {
return static_cast<BlobNeighbourDir>(dir ^ 2);
}
// BlobTextFlowType indicates the quality of neighbouring information
// related to a chain of connected components, either horizontally or
// vertically. Also used by ColPartition for the collection of blobs
// within, which should all have the same value in most cases.
enum BlobTextFlowType {
BTFT_NONE, // No text flow set yet.
BTFT_NONTEXT, // Flow too poor to be likely text.
BTFT_NEIGHBOURS, // Neighbours support flow in this direction.
BTFT_CHAIN, // There is a weak chain of text in this direction.
BTFT_STRONG_CHAIN, // There is a strong chain of text in this direction.
BTFT_TEXT_ON_IMAGE, // There is a strong chain of text on an image.
BTFT_LEADER, // Leader dots/dashes etc.
BTFT_COUNT
};
// Returns true if type1 dominates type2 in a merge. Mostly determined by the
// ordering of the enum, LEADER is weak and dominates nothing.
// The function is anti-symmetric (t1 > t2) === !(t2 > t1), except that
// this cannot be true if t1 == t2, so the result is undefined.
inline bool DominatesInMerge(BlobTextFlowType type1, BlobTextFlowType type2) {
// LEADER always loses.
if (type1 == BTFT_LEADER) return false;
if (type2 == BTFT_LEADER) return true;
// With those out of the way, the ordering of the enum determines the result.
return type1 >= type2;
}
namespace tesseract {
class ColPartition;
}
class BLOBNBOX;
ELISTIZEH (BLOBNBOX)
class BLOBNBOX:public ELIST_LINK
{
public:
BLOBNBOX() {
ConstructionInit();
}
explicit BLOBNBOX(C_BLOB *srcblob) {
box = srcblob->bounding_box();
ConstructionInit();
cblob_ptr = srcblob;
area = static_cast<int>(srcblob->area());
}
~BLOBNBOX() {
if (owns_cblob_) delete cblob_ptr;
}
static BLOBNBOX* RealBlob(C_OUTLINE* outline) {
C_BLOB* blob = new C_BLOB(outline);
return new BLOBNBOX(blob);
}
// Rotates the box and the underlying blob.
void rotate(FCOORD rotation);
// Methods that act on the box without touching the underlying blob.
// Reflect the box in the y-axis, leaving the underlying blob untouched.
void reflect_box_in_y_axis();
// Rotates the box by the angle given by rotation.
// If the blob is a diacritic, then only small rotations for skew
// correction can be applied.
void rotate_box(FCOORD rotation);
// Moves just the box by the given vector.
void translate_box(ICOORD v) {
if (IsDiacritic()) {
box.move(v);
base_char_top_ += v.y();
base_char_bottom_ += v.y();
} else {
box.move(v);
set_diacritic_box(box);
}
}
void merge(BLOBNBOX *nextblob);
void really_merge(BLOBNBOX* other);
void chop( // fake chop blob
BLOBNBOX_IT *start_it, // location of this
BLOBNBOX_IT *blob_it, // iterator
FCOORD rotation, // for landscape
float xheight); // line height
void NeighbourGaps(int gaps[BND_COUNT]) const;
void MinMaxGapsClipped(int* h_min, int* h_max,
int* v_min, int* v_max) const;
void CleanNeighbours();
// Returns positive if there is at least one side neighbour that has a
// similar stroke width and is not on the other side of a rule line.
int GoodTextBlob() const;
// Returns the number of side neighbours that are of type BRT_NOISE.
int NoisyNeighbours() const;
// Returns true if the blob is noise and has no owner.
bool DeletableNoise() const {
return owner() == NULL && region_type() == BRT_NOISE;
}
// Returns true, and sets vert_possible/horz_possible if the blob has some
// feature that makes it individually appear to flow one way.
// eg if it has a high aspect ratio, yet has a complex shape, such as a
// joined word in Latin, Arabic, or Hindi, rather than being a -, I, l, 1.
bool DefiniteIndividualFlow();
// Returns true if there is no tabstop violation in merging this and other.
bool ConfirmNoTabViolation(const BLOBNBOX& other) const;
// Returns true if other has a similar stroke width to this.
bool MatchingStrokeWidth(const BLOBNBOX& other,
double fractional_tolerance,
double constant_tolerance) const;
// Returns a bounding box of the outline contained within the
// given horizontal range.
TBOX BoundsWithinLimits(int left, int right);
// Estimates and stores the baseline position based on the shape of the
// outline.
void EstimateBaselinePosition();
// Simple accessors.
const TBOX& bounding_box() const {
return box;
}
// Set the bounding box. Use with caution.
// Normally use compute_bounding_box instead.
void set_bounding_box(const TBOX& new_box) {
box = new_box;
base_char_top_ = box.top();
base_char_bottom_ = box.bottom();
}
void compute_bounding_box() {
box = cblob_ptr->bounding_box();
base_char_top_ = box.top();
base_char_bottom_ = box.bottom();
baseline_y_ = box.bottom();
}
const TBOX& reduced_box() const {
return red_box;
}
void set_reduced_box(TBOX new_box) {
red_box = new_box;
reduced = TRUE;
}
inT32 enclosed_area() const {
return area;
}
bool joined_to_prev() const {
return joined != 0;
}
bool red_box_set() const {
return reduced != 0;
}
int repeated_set() const {
return repeated_set_;
}
void set_repeated_set(int set_id) {
repeated_set_ = set_id;
}
C_BLOB *cblob() const {
return cblob_ptr;
}
TabType left_tab_type() const {
return left_tab_type_;
}
void set_left_tab_type(TabType new_type) {
left_tab_type_ = new_type;
}
TabType right_tab_type() const {
return right_tab_type_;
}
void set_right_tab_type(TabType new_type) {
right_tab_type_ = new_type;
}
BlobRegionType region_type() const {
return region_type_;
}
void set_region_type(BlobRegionType new_type) {
region_type_ = new_type;
}
BlobSpecialTextType special_text_type() const {
return spt_type_;
}
void set_special_text_type(BlobSpecialTextType new_type) {
spt_type_ = new_type;
}
BlobTextFlowType flow() const {
return flow_;
}
void set_flow(BlobTextFlowType value) {
flow_ = value;
}
bool vert_possible() const {
return vert_possible_;
}
void set_vert_possible(bool value) {
vert_possible_ = value;
}
bool horz_possible() const {
return horz_possible_;
}
void set_horz_possible(bool value) {
horz_possible_ = value;
}
int left_rule() const {
return left_rule_;
}
void set_left_rule(int new_left) {
left_rule_ = new_left;
}
int right_rule() const {
return right_rule_;
}
void set_right_rule(int new_right) {
right_rule_ = new_right;
}
int left_crossing_rule() const {
return left_crossing_rule_;
}
void set_left_crossing_rule(int new_left) {
left_crossing_rule_ = new_left;
}
int right_crossing_rule() const {
return right_crossing_rule_;
}
void set_right_crossing_rule(int new_right) {
right_crossing_rule_ = new_right;
}
float horz_stroke_width() const {
return horz_stroke_width_;
}
void set_horz_stroke_width(float width) {
horz_stroke_width_ = width;
}
float vert_stroke_width() const {
return vert_stroke_width_;
}
void set_vert_stroke_width(float width) {
vert_stroke_width_ = width;
}
float area_stroke_width() const {
return area_stroke_width_;
}
tesseract::ColPartition* owner() const {
return owner_;
}
void set_owner(tesseract::ColPartition* new_owner) {
owner_ = new_owner;
}
bool leader_on_left() const {
return leader_on_left_;
}
void set_leader_on_left(bool flag) {
leader_on_left_ = flag;
}
bool leader_on_right() const {
return leader_on_right_;
}
void set_leader_on_right(bool flag) {
leader_on_right_ = flag;
}
BLOBNBOX* neighbour(BlobNeighbourDir n) const {
return neighbours_[n];
}
bool good_stroke_neighbour(BlobNeighbourDir n) const {
return good_stroke_neighbours_[n];
}
void set_neighbour(BlobNeighbourDir n, BLOBNBOX* neighbour, bool good) {
neighbours_[n] = neighbour;
good_stroke_neighbours_[n] = good;
}
bool IsDiacritic() const {
return base_char_top_ != box.top() || base_char_bottom_ != box.bottom();
}
int base_char_top() const {
return base_char_top_;
}
int base_char_bottom() const {
return base_char_bottom_;
}
int baseline_position() const {
return baseline_y_;
}
int line_crossings() const {
return line_crossings_;
}
void set_line_crossings(int value) {
line_crossings_ = value;
}
void set_diacritic_box(const TBOX& diacritic_box) {
base_char_top_ = diacritic_box.top();
base_char_bottom_ = diacritic_box.bottom();
}
BLOBNBOX* base_char_blob() const {
return base_char_blob_;
}
void set_base_char_blob(BLOBNBOX* blob) {
base_char_blob_ = blob;
}
void set_owns_cblob(bool value) { owns_cblob_ = value; }
bool UniquelyVertical() const {
return vert_possible_ && !horz_possible_;
}
bool UniquelyHorizontal() const {
return horz_possible_ && !vert_possible_;
}
// Returns true if the region type is text.
static bool IsTextType(BlobRegionType type) {
return type == BRT_TEXT || type == BRT_VERT_TEXT;
}
// Returns true if the region type is image.
static bool IsImageType(BlobRegionType type) {
return type == BRT_RECTIMAGE || type == BRT_POLYIMAGE;
}
// Returns true if the region type is line.
static bool IsLineType(BlobRegionType type) {
return type == BRT_HLINE || type == BRT_VLINE;
}
// Returns true if the region type cannot be merged.
static bool UnMergeableType(BlobRegionType type) {
return IsLineType(type) || IsImageType(type);
}
// Helper to call CleanNeighbours on all blobs on the list.
static void CleanNeighbours(BLOBNBOX_LIST* blobs);
// Helper to delete all the deletable blobs on the list.
static void DeleteNoiseBlobs(BLOBNBOX_LIST* blobs);
// Helper to compute edge offsets for all the blobs on the list.
// See coutln.h for an explanation of edge offsets.
static void ComputeEdgeOffsets(Pix* thresholds, Pix* grey,
BLOBNBOX_LIST* blobs);
#ifndef GRAPHICS_DISABLED
// Helper to draw all the blobs on the list in the given body_colour,
// with child outlines in the child_colour.
static void PlotBlobs(BLOBNBOX_LIST* list,
ScrollView::Color body_colour,
ScrollView::Color child_colour,
ScrollView* win);
// Helper to draw only DeletableNoise blobs (unowned, BRT_NOISE) on the
// given list in the given body_colour, with child outlines in the
// child_colour.
static void PlotNoiseBlobs(BLOBNBOX_LIST* list,
ScrollView::Color body_colour,
ScrollView::Color child_colour,
ScrollView* win);
static ScrollView::Color TextlineColor(BlobRegionType region_type,
BlobTextFlowType flow_type);
// Keep in sync with BlobRegionType.
ScrollView::Color BoxColor() const;
void plot(ScrollView* window, // window to draw in
ScrollView::Color blob_colour, // for outer bits
ScrollView::Color child_colour); // for holes
#endif
// Initializes the bulk of the members to default values for use at
// construction time.
void ConstructionInit() {
cblob_ptr = NULL;
owns_cblob_ = false;
area = 0;
area_stroke_width_ = 0.0f;
horz_stroke_width_ = 0.0f;
vert_stroke_width_ = 0.0f;
ReInit();
}
// Initializes members set by StrokeWidth and beyond, without discarding
// stored area and strokewidth values, which are expensive to calculate.
void ReInit() {
joined = false;
reduced = false;
repeated_set_ = 0;
left_tab_type_ = TT_NONE;
right_tab_type_ = TT_NONE;
region_type_ = BRT_UNKNOWN;
flow_ = BTFT_NONE;
spt_type_ = BSTT_SKIP;
left_rule_ = 0;
right_rule_ = 0;
left_crossing_rule_ = 0;
right_crossing_rule_ = 0;
if (area_stroke_width_ == 0.0f && area > 0 && cblob() != NULL)
area_stroke_width_ = 2.0f * area / cblob()->perimeter();
owner_ = NULL;
base_char_top_ = box.top();
base_char_bottom_ = box.bottom();
baseline_y_ = box.bottom();
line_crossings_ = 0;
base_char_blob_ = NULL;
horz_possible_ = false;
vert_possible_ = false;
leader_on_left_ = false;
leader_on_right_ = false;
ClearNeighbours();
}
void ClearNeighbours() {
for (int n = 0; n < BND_COUNT; ++n) {
neighbours_[n] = NULL;
good_stroke_neighbours_[n] = false;
}
}
private:
C_BLOB *cblob_ptr; // edgestep blob
TBOX box; // bounding box
TBOX red_box; // bounding box
int area:30; // enclosed area
int joined:1; // joined to prev
int reduced:1; // reduced box set
int repeated_set_; // id of the set of repeated blobs
TabType left_tab_type_; // Indicates tab-stop assessment
TabType right_tab_type_; // Indicates tab-stop assessment
BlobRegionType region_type_; // Type of region this blob belongs to
BlobTextFlowType flow_; // Quality of text flow.
inT16 left_rule_; // x-coord of nearest but not crossing rule line
inT16 right_rule_; // x-coord of nearest but not crossing rule line
inT16 left_crossing_rule_; // x-coord of nearest or crossing rule line
inT16 right_crossing_rule_; // x-coord of nearest or crossing rule line
inT16 base_char_top_; // y-coord of top/bottom of diacritic base,
inT16 base_char_bottom_; // if it exists else top/bottom of this blob.
inT16 baseline_y_; // Estimate of baseline position.
int line_crossings_; // Number of line intersections touched.
BLOBNBOX* base_char_blob_; // The blob that was the base char.
float horz_stroke_width_; // Median horizontal stroke width
float vert_stroke_width_; // Median vertical stroke width
float area_stroke_width_; // Stroke width from area/perimeter ratio.
tesseract::ColPartition* owner_; // Who will delete me when I am not needed
BlobSpecialTextType spt_type_; // Special text type.
BLOBNBOX* neighbours_[BND_COUNT];
bool good_stroke_neighbours_[BND_COUNT];
bool horz_possible_; // Could be part of horizontal flow.
bool vert_possible_; // Could be part of vertical flow.
bool leader_on_left_; // There is a leader to the left.
bool leader_on_right_; // There is a leader to the right.
// Iff true, then the destructor should delete the cblob_ptr.
// TODO(rays) migrate all uses to correctly setting this flag instead of
// deleting the C_BLOB before deleting the BLOBNBOX.
bool owns_cblob_;
};
class TO_ROW: public ELIST2_LINK
{
public:
static const int kErrorWeight = 3;
TO_ROW() {
clear();
} //empty
TO_ROW( //constructor
BLOBNBOX *blob, //from first blob
float top, //of row //target height
float bottom,
float row_size);
void print() const;
float max_y() const { //access function
return y_max;
}
float min_y() const {
return y_min;
}
float mean_y() const {
return (y_min + y_max) / 2.0f;
}
float initial_min_y() const {
return initial_y_min;
}
float line_m() const { //access to line fit
return m;
}
float line_c() const {
return c;
}
float line_error() const {
return error;
}
float parallel_c() const {
return para_c;
}
float parallel_error() const {
return para_error;
}
float believability() const { //baseline goodness
return credibility;
}
float intercept() const { //real parallel_c
return y_origin;
}
void add_blob( //put in row
BLOBNBOX *blob, //blob to add
float top, //of row //target height
float bottom,
float row_size);
void insert_blob( //put in row in order
BLOBNBOX *blob);
BLOBNBOX_LIST *blob_list() { //get list
return &blobs;
}
void set_line( //set line spec
float new_m, //line to set
float new_c,
float new_error) {
m = new_m;
c = new_c;
error = new_error;
}
void set_parallel_line( //set fixed gradient line
float gradient, //page gradient
float new_c,
float new_error) {
para_c = new_c;
para_error = new_error;
credibility =
(float) (blobs.length () - kErrorWeight * new_error);
y_origin = (float) (new_c / sqrt (1 + gradient * gradient));
//real intercept
}
void set_limits( //set min,max
float new_min, //bottom and
float new_max) { //top of row
y_min = new_min;
y_max = new_max;
}
void compute_vertical_projection();
//get projection
bool rep_chars_marked() const {
return num_repeated_sets_ != -1;
}
void clear_rep_chars_marked() {
num_repeated_sets_ = -1;
}
int num_repeated_sets() const {
return num_repeated_sets_;
}
void set_num_repeated_sets(int num_sets) {
num_repeated_sets_ = num_sets;
}
// true when dead
BOOL8 merged;
BOOL8 all_caps; // had no ascenders
BOOL8 used_dm_model; // in guessing pitch
inT16 projection_left; // start of projection
inT16 projection_right; // start of projection
PITCH_TYPE pitch_decision; // how strong is decision
float fixed_pitch; // pitch or 0
float fp_space; // sp if fixed pitch
float fp_nonsp; // nonsp if fixed pitch
float pr_space; // sp if prop
float pr_nonsp; // non sp if prop
float spacing; // to "next" row
float xheight; // of line
int xheight_evidence; // number of blobs of height xheight
float ascrise; // ascenders
float descdrop; // descenders
float body_size; // of CJK characters. Assumed to be
// xheight+ascrise for non-CJK text.
inT32 min_space; // min size for real space
inT32 max_nonspace; // max size of non-space
inT32 space_threshold; // space vs nonspace
float kern_size; // average non-space
float space_size; // average space
WERD_LIST rep_words; // repeated chars
ICOORDELT_LIST char_cells; // fixed pitch cells
QSPLINE baseline; // curved baseline
STATS projection; // vertical projection
private:
void clear(); // clear all values to reasonable defaults
BLOBNBOX_LIST blobs; //blobs in row
float y_min; //coords
float y_max;
float initial_y_min;
float m, c; //line spec
float error; //line error
float para_c; //constrained fit
float para_error;
float y_origin; //rotated para_c;
float credibility; //baseline believability
int num_repeated_sets_; // number of sets of repeated blobs
// set to -1 if we have not searched
// for repeated blobs in this row yet
};
ELIST2IZEH (TO_ROW)
class TO_BLOCK:public ELIST_LINK
{
public:
TO_BLOCK() : pitch_decision(PITCH_DUNNO) {
clear();
} //empty
TO_BLOCK( //constructor
BLOCK *src_block); //real block
~TO_BLOCK();
void clear(); // clear all scalar members.
TO_ROW_LIST *get_rows() { //access function
return &row_list;
}
// Rotate all the blobnbox lists and the underlying block. Then update the
// median size statistic from the blobs list.
void rotate(const FCOORD& rotation) {
BLOBNBOX_LIST* blobnbox_list[] = {&blobs, &underlines, &noise_blobs,
&small_blobs, &large_blobs, NULL};
for (BLOBNBOX_LIST** list = blobnbox_list; *list != NULL; ++list) {
BLOBNBOX_IT it(*list);
for (it.mark_cycle_pt(); !it.cycled_list(); it.forward()) {
it.data()->rotate(rotation);
}
}
// Rotate the block
ASSERT_HOST(block->poly_block() != NULL);
block->rotate(rotation);
// Update the median size statistic from the blobs list.
STATS widths(0, block->bounding_box().width());
STATS heights(0, block->bounding_box().height());
BLOBNBOX_IT blob_it(&blobs);
for (blob_it.mark_cycle_pt(); !blob_it.cycled_list(); blob_it.forward()) {
widths.add(blob_it.data()->bounding_box().width(), 1);
heights.add(blob_it.data()->bounding_box().height(), 1);
}
block->set_median_size(static_cast<int>(widths.median() + 0.5),
static_cast<int>(heights.median() + 0.5));
}
void print_rows() { //debug info
TO_ROW_IT row_it = &row_list;
TO_ROW *row;
for (row_it.mark_cycle_pt(); !row_it.cycled_list();
row_it.forward()) {
row = row_it.data();
tprintf("Row range (%g,%g), para_c=%g, blobcount=" INT32FORMAT
"\n", row->min_y(), row->max_y(), row->parallel_c(),
row->blob_list()->length());
}
}
// Reorganizes the blob lists with a different definition of small, medium
// and large, compared to the original definition.
// Height is still the primary filter key, but medium width blobs of small
// height become medium, and very wide blobs of small height stay small.
void ReSetAndReFilterBlobs();
// Deletes noise blobs from all lists where not owned by a ColPartition.
void DeleteUnownedNoise();
// Computes and stores the edge offsets on each blob for use in feature
// extraction, using greyscale if the supplied grey and thresholds pixes
// are 8-bit or otherwise (if NULL or not 8 bit) the original binary
// edge step outlines.
// Thresholds must either be the same size as grey or an integer down-scale
// of grey.
// See coutln.h for an explanation of edge offsets.
void ComputeEdgeOffsets(Pix* thresholds, Pix* grey);
#ifndef GRAPHICS_DISABLED
// Draw the noise blobs from all lists in red.
void plot_noise_blobs(ScrollView* to_win);
// Draw the blobs on on the various lists in the block in different colors.
void plot_graded_blobs(ScrollView* to_win);
#endif
BLOBNBOX_LIST blobs; //medium size
BLOBNBOX_LIST underlines; //underline blobs
BLOBNBOX_LIST noise_blobs; //very small
BLOBNBOX_LIST small_blobs; //fairly small
BLOBNBOX_LIST large_blobs; //big blobs
BLOCK *block; //real block
PITCH_TYPE pitch_decision; //how strong is decision
float line_spacing; //estimate
// line_size is a lower-bound estimate of the font size in pixels of
// the text in the block (with ascenders and descenders), being a small
// (1.25) multiple of the median height of filtered blobs.
// In most cases the font size will be bigger, but it will be closer
// if the text is allcaps, or in a no-x-height script.
float line_size; //estimate
float max_blob_size; //line assignment limit
float baseline_offset; //phase shift
float xheight; //median blob size
float fixed_pitch; //pitch or 0
float kern_size; //average non-space
float space_size; //average space
inT32 min_space; //min definite space
inT32 max_nonspace; //max definite
float fp_space; //sp if fixed pitch
float fp_nonsp; //nonsp if fixed pitch
float pr_space; //sp if prop
float pr_nonsp; //non sp if prop
TO_ROW *key_row; //starting row
private:
TO_ROW_LIST row_list; //temporary rows
};
ELISTIZEH (TO_BLOCK)
extern double_VAR_H (textord_error_weight, 3,
"Weighting for error in believability");
void find_cblob_limits( //get y limits
C_BLOB *blob, //blob to search
float leftx, //x limits
float rightx,
FCOORD rotation, //for landscape
float &ymin, //output y limits
float &ymax);
void find_cblob_vlimits( //get y limits
C_BLOB *blob, //blob to search
float leftx, //x limits
float rightx,
float &ymin, //output y limits
float &ymax);
void find_cblob_hlimits( //get x limits
C_BLOB *blob, //blob to search
float bottomy, //y limits
float topy,
float &xmin, //output x limits
float &xymax);
C_BLOB *crotate_cblob( //rotate it
C_BLOB *blob, //blob to search
FCOORD rotation //for landscape
);
TBOX box_next( //get bounding box
BLOBNBOX_IT *it //iterator to blobds
);
TBOX box_next_pre_chopped( //get bounding box
BLOBNBOX_IT *it //iterator to blobds
);
void vertical_cblob_projection( //project outlines
C_BLOB *blob, //blob to project
STATS *stats //output
);
void vertical_coutline_projection( //project outlines
C_OUTLINE *outline, //outline to project
STATS *stats //output
);
#ifndef GRAPHICS_DISABLED
void plot_blob_list(ScrollView* win, // window to draw in
BLOBNBOX_LIST *list, // blob list
ScrollView::Color body_colour, // colour to draw
ScrollView::Color child_colour); // colour of child
#endif // GRAPHICS_DISABLED
#endif