In This Topic ▼

LBitmap::LineRemove

Summary

Removes horizontal and vertical lines in a 1-bit black and white image.

Syntax

#include "ltwrappr.h"

virtual L_INT LBitmap::LineRemove(pLineRemove, uFlags = 0)

Parameters

pLINEREMOVE pLineRemove

Pointer to the LINEREMOVE structure that LEADTOOLS uses to perform the line removal operation.

Returns

Value	Meaning
SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

This function removes horizontal and vertical lines from scanned text documents. If the lines pass through text, the pLineRemove parameter can be configured to remove or preserve the text.

This function works only on 1-bit black and white images.

If a region is selected, only the selected region will be changed by this function. If no region is selected, the whole image will be processed.

The behavior of this function can be further modified by overriding LBitmap::LineRemoveCallback.

This function does not support signed data images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image is passed to this function.

This function does not support 32-bit grayscale images. It returns the error code ERROR_GRAY32_UNSUPPORTED if a 32-bit grayscale image is passed to this function.

Line Remove Function - Before

Line Remove Function - After

View additional platform support for this Line Remove function.

Required DLLs and Libraries

LTIMGCOR
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Example

This example removes vertical lines that are at least 200 pixels in length
and no more than 5 pixels in width
The lines can have gaps up to two pixels in length.
The derived class LMyBitmap is used to override the LineRemoveCallBack function.
myBitmap is an object of class LMyBitmap.
The callback member function is used to display information about each line removed.
The callback member function does NOT receive a Windows region.

class LLineRemoveBitmap : public LBitmap 
{ 
public: 
   LLineRemoveBitmap(); 
   ~LLineRemoveBitmap(); 
 
   virtual L_INT LineRemoveCallBack(L_UINT32       uBumpOrNick, 
                                    L_INT32        iStartRow,  
                                    L_INT32        iStartCol,  
                                    L_INT32        iLength, 
                                    L_UINT32       uHorV 
                                    ); 
}; 
 
LLineRemoveBitmap::LLineRemoveBitmap() 
{ 
} 
 
LLineRemoveBitmap::~LLineRemoveBitmap() 
{ 
} 
 
L_INT LLineRemoveBitmap::LineRemoveCallBack(L_UINT32 uBumpOrNick, 
                                             L_INT32 iStartRow,  
                                             L_INT32 iStartCol,  
                                             L_INT32 iLength, 
                                             L_UINT32 uHorV 
                                             ) 
{ 
   UNREFERENCED_PARAMETER(uHorV); 
   UNREFERENCED_PARAMETER(uBumpOrNick); 
 
   CString strMsg; 
 
  strMsg.Format( 
     TEXT("RowCol[%d,%d] Length[%d]\n"), 
     iStartRow, 
     iStartCol, 
     iLength 
     ); 
  OutputDebugString(strMsg); 
  return SUCCESS_REMOVE;  
} 
 
L_INT LBitmap__LineRemoveExample(LBitmapWindow *pBitmapWindow) 
{ 
   LINEREMOVE        lr; 
 
   lr.uStructSize    = sizeof(LINEREMOVE); 
   lr.uBitmapStructSize        = sizeof(BITMAPHANDLE); 
   lr.iGapLength     = 2; 
   lr.iMaxLineWidth  = 5; 
   lr.iMinLineLength = 200; 
   lr.iWall          = 7; 
   lr.iMaxWallPercent   = 10; 
   lr.uRemoveFlags   = LINEREMOVE_HORIZONTAL; 
   lr.uFlags         = LINE_USE_GAP; 
   lr.pBitmapRegion  = NULL; 
 
   pBitmapWindow->LineRemove(&lr); 
 
   return SUCCESS; 
}