IsBlank(Int32,Single,Boolean,Boolean) Method
 
            
                In This Topic
            
            
            Detects if a GdPicture image or on an area of a GdPicture image defined by SetROI() method is blank, with option to account for margins.
            
            
            
            Syntax
            
            
            
            
            'Declaration
 
Public Overloads Function IsBlank( _
   ByVal  As Integer, _
   ByVal  As Single, _
   ByVal  As Boolean, _
   ByVal  As Boolean _
) As Boolean
             
        
            
            public bool IsBlank( 
   int ,
   float ,
   bool ,
   bool 
)
             
        
            
            public function IsBlank( 
    : Integer;
    : Single;
    : Boolean;
    : Boolean
): Boolean; 
             
        
            
            public function IsBlank( 
    : int,
    : float,
    : boolean,
    : boolean
) : boolean;
             
        
            
            public: bool IsBlank( 
   int ,
   float ,
   bool ,
   bool 
) 
             
        
            
            public:
bool IsBlank( 
   int ,
   float ,
   bool ,
   bool 
) 
             
        
             
        
            Parameters
- ImageID
 
- GdPicture image identifier.
 - Confidence
 
- Confidence threshold in the range [0 - 100]. Suggested value is 99.5.
 - AccountForMargins
 
- Specifies if the algorithm must drop the margins during the calculation (slower). Yields more accurate results for images with margins. Default value is true.
 - AccountForPunchHoles
 
- Specifies if the algorithm must drop the punch holes during the calculation (slower). Yields more accurate results for images with punch holes. Default value is true.
 
            
            Return Value
            True if it is a blank image, else False.
            
 
            
            
            
            
            
            Example
Removing the blank pages from a tiff document.
            
            
             
    
	
		using (GdPictureImaging gdpictureImaging = new GdPictureImaging())
{
    // LoadInMemory parameter is set to true in order to be able to update the input file.
    int imageID = gdpictureImaging.TiffCreateMultiPageFromFile("multipage.tif", true);
    int pageCount = gdpictureImaging.TiffGetPageCount(imageID);
    int pageNo = 1;
    while (pageNo <= pageCount)
    {
        gdpictureImaging.TiffSelectPage(imageID, pageNo);
        if (gdpictureImaging.IsBlank(imageID, 95, false, false))
        {
            gdpictureImaging.TiffDeletePage(imageID, pageNo);
            pageCount--;
        }
        else
        {
            pageNo++;
        }
    }
    gdpictureImaging.TiffSaveMultiPageToFile(imageID, "multipage.tif", TiffCompression.TiffCompressionAUTO);
    gdpictureImaging.ReleaseGdPictureImage(imageID);
}
	 
	
 
 
            
            Example
Removing the blank pages from a tiff document.
            
            using (GdPictureImaging gdpictureImaging = new GdPictureImaging())
            {
                // LoadInMemory parameter is set to true in order to be able to update the input file.
                int imageID = gdpictureImaging.TiffCreateMultiPageFromFile("multipage.tif", true);
                int pageCount = gdpictureImaging.TiffGetPageCount(imageID);
                int pageNo = 1;
                while (pageNo <= pageCount)
                {
                    gdpictureImaging.TiffSelectPage(imageID, pageNo);
                    if (gdpictureImaging.IsBlank(imageID, 95, false, false))
                    {
                        gdpictureImaging.TiffDeletePage(imageID, pageNo);
                        pageCount--;
                    }
                    else
                    {
                        pageNo++;
                    }
                }
                gdpictureImaging.TiffSaveMultiPageToFile(imageID, "multipage.tif", TiffCompression.TiffCompressionAUTO);
                gdpictureImaging.ReleaseGdPictureImage(imageID);
            }
            
            
            
            See Also