tesseract::IntGrid Class Reference

#include <bbgrid.h>

Inheritance diagram for tesseract::IntGrid:

Public Member Functions
	IntGrid ()
	IntGrid (int gridsize, const ICOORD &bleft, const ICOORD &tright)
virtual	~IntGrid ()
void	Init (int gridsize, const ICOORD &bleft, const ICOORD &tright)
void	Clear ()
void	Rotate (const FCOORD &rotation)
IntGrid *	NeighbourhoodSum () const
int	GridCellValue (int grid_x, int grid_y) const
void	SetGridCell (int grid_x, int grid_y, int value)
bool	RectMostlyOverThreshold (const TBOX &rect, int threshold) const
bool	AnyZeroInRect (const TBOX &rect) const
Pix *	ThresholdToPix (int threshold) const
Public Member Functions inherited from tesseract::GridBase
	GridBase ()=default
	GridBase (int gridsize, const ICOORD &bleft, const ICOORD &tright)
virtual	~GridBase ()
void	Init (int gridsize, const ICOORD &bleft, const ICOORD &tright)
int	gridsize () const
int	gridwidth () const
int	gridheight () const
const ICOORD &	bleft () const
const ICOORD &	tright () const
void	GridCoords (int x, int y, int *grid_x, int *grid_y) const
void	ClipGridCoords (int *x, int *y) const

Additional Inherited Members
Protected Attributes inherited from tesseract::GridBase
int	gridsize_
int	gridwidth_
int	gridheight_
int	gridbuckets_
ICOORD	bleft_
ICOORD	tright_

Detailed Description

Definition at line 98 of file bbgrid.h.

Constructor & Destructor Documentation

IntGrid() [1/2]

tesseract::IntGrid::IntGrid

(

)

Definition at line 65 of file bbgrid.cpp.

                 {
  grid_ = nullptr;
}

IntGrid() [2/2]

tesseract::IntGrid::IntGrid	(	int	gridsize,
		const ICOORD &	bleft,
		const ICOORD &	tright
	)

Definition at line 69 of file bbgrid.cpp.

  : grid_(nullptr) {
  Init(gridsize, bleft, tright);
}

~IntGrid()

tesseract::IntGrid::~IntGrid ( )

virtual

Definition at line 74 of file bbgrid.cpp.

                  {
  delete [] grid_;
}

Member Function Documentation

AnyZeroInRect()

bool tesseract::IntGrid::AnyZeroInRect

(

const TBOX &

rect

)

const

Definition at line 175 of file bbgrid.cpp.

                                                  {
  int min_x, min_y, max_x, max_y;
  GridCoords(rect.left(), rect.bottom(), &min_x, &min_y);
  GridCoords(rect.right(), rect.top(), &max_x, &max_y);
  for (int y = min_y; y <= max_y; ++y) {
    for (int x = min_x; x <= max_x; ++x) {
      if (GridCellValue(x, y) == 0)
        return true;
    }
  }
  return false;
}

Clear()

void tesseract::IntGrid::Clear

(

)

Definition at line 88 of file bbgrid.cpp.

                    {
  for (int i = 0; i < gridbuckets_; ++i) {
    grid_[i] = 0;
  }
}

GridCellValue()

int tesseract::IntGrid::GridCellValue ( int  grid_x, int  grid_y  ) const

inline

Definition at line 121 of file bbgrid.h.

                                                  {
    ClipGridCoords(&grid_x, &grid_y);
    return grid_[grid_y * gridwidth_ + grid_x];
  }

Init()

void tesseract::IntGrid::Init	(	int	gridsize,
		const ICOORD &	bleft,
		const ICOORD &	tright
	)

Definition at line 80 of file bbgrid.cpp.

                                                                          {
  GridBase::Init(gridsize, bleft, tright);
  delete [] grid_;
  grid_ = new int[gridbuckets_];
  Clear();
}

NeighbourhoodSum()

IntGrid * tesseract::IntGrid::NeighbourhoodSum

(

)

const

Definition at line 133 of file bbgrid.cpp.

                                         {
  IntGrid* sumgrid = new IntGrid(gridsize(), bleft(), tright());
  for (int y = 0; y < gridheight(); ++y) {
    for (int x = 0; x < gridwidth(); ++x) {
      int cell_count = 0;
      for (int yoffset = -1; yoffset <= 1; ++yoffset) {
        for (int xoffset = -1; xoffset <= 1; ++xoffset) {
          int grid_x = x + xoffset;
          int grid_y = y + yoffset;
          ClipGridCoords(&grid_x, &grid_y);
          cell_count += GridCellValue(grid_x, grid_y);
        }
      }
      if (GridCellValue(x, y) > 1)
        sumgrid->SetGridCell(x, y, cell_count);
    }
  }
  return sumgrid;
}

RectMostlyOverThreshold()

bool tesseract::IntGrid::RectMostlyOverThreshold	(	const TBOX &	rect,
		int	threshold
	)		const

Definition at line 155 of file bbgrid.cpp.

                                                                           {
  int min_x, min_y, max_x, max_y;
  GridCoords(rect.left(), rect.bottom(), &min_x, &min_y);
  GridCoords(rect.right(), rect.top(), &max_x, &max_y);
  int total_area = 0;
  for (int y = min_y; y <= max_y; ++y) {
    for (int x = min_x; x <= max_x; ++x) {
      int value = GridCellValue(x, y);
      if (value > threshold) {
        TBOX cell_box(x * gridsize_, y * gridsize_,
                      (x + 1) * gridsize_, (y + 1) * gridsize_);
        cell_box &= rect;  // This is in-place box intersection.
        total_area += cell_box.area();
      }
    }
  }
  return total_area * 2 > rect.area();
}

Rotate()

void tesseract::IntGrid::Rotate

(

const FCOORD &

rotation

)

Definition at line 100 of file bbgrid.cpp.

                                           {
  ASSERT_HOST(rotation.x() == 0.0f || rotation.y() == 0.0f);
  ICOORD old_bleft(bleft());
  ICOORD old_tright(tright());
  int old_width = gridwidth();
  int old_height = gridheight();
  TBOX box(bleft(), tright());
  box.rotate(rotation);
  int* old_grid = grid_;
  grid_ = nullptr;
  Init(gridsize(), box.botleft(), box.topright());
  // Iterate over the old grid, copying data to the rotated position in the new.
  int oldi = 0;
  FCOORD x_step(rotation);
  x_step *= gridsize();
  for (int oldy = 0; oldy < old_height; ++oldy) {
    FCOORD line_pos(old_bleft.x(), old_bleft.y() + gridsize() * oldy);
    line_pos.rotate(rotation);
    for (int oldx = 0; oldx < old_width; ++oldx, line_pos += x_step, ++oldi) {
      int grid_x, grid_y;
      GridCoords(static_cast<int>(line_pos.x() + 0.5),
                 static_cast<int>(line_pos.y() + 0.5),
                 &grid_x, &grid_y);
      grid_[grid_y * gridwidth() + grid_x] = old_grid[oldi];
    }
  }
  delete [] old_grid;
}

SetGridCell()

void tesseract::IntGrid::SetGridCell ( int  grid_x, int  grid_y, int  value  )

inline

Definition at line 125 of file bbgrid.h.

                                                      {
    ASSERT_HOST(grid_x >= 0 && grid_x < gridwidth());
    ASSERT_HOST(grid_y >= 0 && grid_y < gridheight());
    grid_[grid_y * gridwidth_ + grid_x] = value;
  }

ThresholdToPix()

Pix * tesseract::IntGrid::ThresholdToPix

(

int

threshold

)

const

Definition at line 191 of file bbgrid.cpp.

                                                {
  Pix* pix = pixCreate(tright().x() - bleft().x(),
                       tright().y() - bleft().y(), 1);
  int cellsize = gridsize();
  for (int y = 0; y < gridheight(); ++y) {
    for (int x = 0; x < gridwidth(); ++x) {
      if (GridCellValue(x, y) > threshold &&
          GridCellValue(x - 1, y) > 0 && GridCellValue(x + 1, y) > 0 &&
              GridCellValue(x, y - 1) > 0 && GridCellValue(x, y + 1) > 0) {
        pixRasterop(pix, x * cellsize, tright().y() - ((y + 1) * cellsize),
                    cellsize, cellsize, PIX_SET, nullptr, 0, 0);
      }
    }
  }
  return pix;
}

---

The documentation for this class was generated from the following files:

• /usr/src/tesseract-ocr.master/src/textord/bbgrid.h
• /usr/src/tesseract-ocr.master/src/textord/bbgrid.cpp