GdPicture.NET.14~GdPicture14.GdPicturePDF~ConvertToGrayscale(Boolean,Boolean,Boolean,Boolean,Boolean) - ConvertToGrayscale(Boolean,Boolean,Boolean,Boolean,Boolean) Method -

public GdPictureStatus ConvertToGrayscale( 
   bool Text,
   bool Graphics,
   bool Images,
   bool Annotations,
   bool FormFields
)

public function ConvertToGrayscale( 
    Text: Boolean;
    Graphics: Boolean;
    Images: Boolean;
    Annotations: Boolean;
    FormFields: Boolean
): GdPictureStatus;

public function ConvertToGrayscale( 
   Text : boolean,
   Graphics : boolean,
   Images : boolean,
   Annotations : boolean,
   FormFields : boolean
) : GdPictureStatus;

public: GdPictureStatus ConvertToGrayscale( 
   bool Text,
   bool Graphics,
   bool Images,
   bool Annotations,
   bool FormFields
)

public:
GdPictureStatus ConvertToGrayscale( 
   bool Text,
   bool Graphics,
   bool Images,
   bool Annotations,
   bool FormFields
)

'Declaration
 
Public Overloads Function ConvertToGrayscale( _
   ByVal Text As Boolean, _
   ByVal Graphics As Boolean, _
   ByVal Images As Boolean, _
   ByVal Annotations As Boolean, _
   ByVal FormFields As Boolean _
) As GdPictureStatus

Parameters

Text: Set this parameter to true if you want to convert all text on page to grayscale, otherwise set it to false.
Graphics: Set this parameter to true if you want to convert all path - based graphic objects on page to grayscale, otherwise set it to false.
Images: Set this parameter to true if you want to convert all images on page to grayscale, otherwise set it to false.
Annotations: Set this parameter to true if you want to convert all annotations on page to grayscale, otherwise set it to false.
FormFields: Set this parameter to true if you want to convert all form fields on page to grayscale, otherwise set it to false.

Return Value

A member of the GdPictureStatus enumeration. If the method has been successfully followed, then the return value is GdPictureStatus.OK.

We strongly recommend always checking this status first.

How to convert images on the selected page to grayscale.

VB.NET
C#

Using gdpicturePDF As New GdPicturePDF
    gdpicturePDF.LoadFromFile("input.pdf")
    gdpicturePDF.SelectPage(2)
    gdpicturePDF.ConvertToGrayscale(False, False, True, False, False)
    gdpicturePDF.SaveToFile("output.pdf")
End Using

using (GdPicturePDF gdpicturePDF = new GdPicturePDF())
{
    gdpicturePDF.LoadFromFile("input.pdf");
    gdpicturePDF.SelectPage(2);
    gdpicturePDF.ConvertToGrayscale(false, false, true, false, false);
    gdpicturePDF.SaveToFile("output.pdf");
}

Reference

GdPicturePDF Class
GdPicturePDF Members
Overload List