The 0-based index of the image within the current page. It must be a value from 0 to GdPicturePDF.GetPageImageCount-1.
Output parameter. The horizontal resolution (DPI) of the specified image.
Output parameter. The vertical resolution (DPI) of the specified image.
Example





In This Topic
GdPicture14 Namespace / GdPicturePDF Class / GetPageImageResolution Method

GetPageImageResolution Method (GdPicturePDF)

In This Topic
Returns the vertical and the horizontal resolution (DPI) of an image, specified by its index within the currently selected page of the loaded PDF document.
Syntax
'Declaration

 

Public Function GetPageImageResolution( _

   ByVal ImageIdx As Integer, _

   ByRef HorizontalResolution As Single, _

   ByRef VerticalResolution As Single _

) As GdPictureStatus
public GdPictureStatus GetPageImageResolution( 

   int ImageIdx,

   ref float HorizontalResolution,

   ref float VerticalResolution

)
public function GetPageImageResolution( 

    ImageIdx: Integer;

   var  HorizontalResolution: Single;

   var  VerticalResolution: Single

): GdPictureStatus; 
public function GetPageImageResolution( 

   ImageIdx : int,

   HorizontalResolution : float,

   VerticalResolution : float

) : GdPictureStatus;
public: GdPictureStatus GetPageImageResolution( 

   int ImageIdx,

   ref float HorizontalResolution,

   ref float VerticalResolution

) 
public:

GdPictureStatus GetPageImageResolution( 

   int ImageIdx,

   float% HorizontalResolution,

   float% VerticalResolution

) 

Parameters

ImageIdx
The 0-based index of the image within the current page. It must be a value from 0 to GdPicturePDF.GetPageImageCount-1.
HorizontalResolution
Output parameter. The horizontal resolution (DPI) of the specified image.
VerticalResolution
Output parameter. The vertical resolution (DPI) of the specified image.

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.

Remarks
This method is only allowed for use with non-encrypted documents.
Example
How to find out the resolution (both horizontal and vertical) of all images contained within the PDF document.
Dim caption As String = "Example: GetPageImageResolution"

Dim gdpicturePDF As New GdPicturePDF()

If gdpicturePDF.LoadFromFile("test.pdf", False) = GdPictureStatus.OK Then

    Dim message As String = ""

    Dim pageCount As Integer = gdpicturePDF.GetPageCount()

    Dim status As GdPictureStatus = gdpicturePDF.GetStat()

    If (status = GdPictureStatus.OK) AndAlso (pageCount > 0) Then

        For i As Integer = 1 To pageCount

            If gdpicturePDF.SelectPage(i) = GdPictureStatus.OK Then

                message = message + "Page nr." + i.ToString() + ":" + vbCrLf

                Dim imageCount As Integer = gdpicturePDF.GetPageImageCount()

                status = gdpicturePDF.GetStat()

                If (status = GdPictureStatus.OK) AndAlso (imageCount > 0) Then

                    Dim hRes As Single = 0, vRes As Single = 0

                    For j As Integer = 0 To imageCount - 1

                        status = gdpicturePDF.GetPageImageResolution(j, hRes, vRes)

                        If status = GdPictureStatus.OK Then

                            message = message + "The image indexed as " + j.ToString() + " has the following resolution: horizontal = " + hRes.ToString() + ", vertical = " + vRes.ToString() + "." + vbCrLf

                        Else

                            message = message + "The GetPageImageResolution() method has failed for the image nr. " + j.ToString() + " with the status: " + status.ToString() + vbCrLf

                        End If

                    Next

                Else

                    If status = GdPictureStatus.OK Then

                        message = message + "This page doesn't contain any image." + vbCrLf

                    Else

                        message = message + "The GetPageImageCount() method has failed with the status: " + status.ToString() + vbCrLf

                    End If

                End If

            Else

                message = message + "The SelectPage() method has failed for the page nr. " + i.ToString() + " with the status: " + gdpicturePDF.GetStat().ToString() + vbCrLf

            End If

        Next

        MessageBox.Show(message, caption)

    Else

        If status = GdPictureStatus.OK Then

            MessageBox.Show("This file doesn't contain any page.", caption)

        Else

            MessageBox.Show("The GetPageCount() method has failed with the status: " + status.ToString(), caption)

        End If

    End If

Else

    MessageBox.Show("The file can't be loaded.", caption)

End If

gdpicturePDF.Dispose()
string caption = "Example: GetPageImageResolution";

GdPicturePDF gdpicturePDF = new GdPicturePDF();

if (gdpicturePDF.LoadFromFile("test.pdf", false) == GdPictureStatus.OK)

{

    string message = "";

    int pageCount = gdpicturePDF.GetPageCount();

    GdPictureStatus status = gdpicturePDF.GetStat();

    if ((status == GdPictureStatus.OK) && (pageCount > 0))

    {

        for (int i = 1; i <= pageCount; i++)

        {

            if (gdpicturePDF.SelectPage(i) == GdPictureStatus.OK)

            {

                message = message + "Page nr." + i.ToString() + ":\n";

                int imageCount = gdpicturePDF.GetPageImageCount();

                status = gdpicturePDF.GetStat();

                if ((status == GdPictureStatus.OK) && (imageCount > 0))

                {

                    float hRes = 0, vRes = 0;

                    for (int j = 0; j < imageCount; j++)

                    {

                        status = gdpicturePDF.GetPageImageResolution(j, ref hRes, ref vRes);

                        if (status == GdPictureStatus.OK)

                            message = message + "The image indexed as " + j.ToString() + " has the following resolution: horizontal = " + hRes.ToString() + ", vertical = " + vRes.ToString() + ".\n";

                        else

                            message = message + "The GetPageImageResolution() method has failed for the image nr. " + j.ToString() + " with the status: " + status.ToString() + "\n";

                    }

                }

                else

                {

                    if (status == GdPictureStatus.OK)

                        message = message + "This page doesn't contain any image.\n";

                    else

                        message = message + "The GetPageImageCount() method has failed with the status: " + status.ToString() + "\n";

                }

            }

            else

            {

                message = message + "The SelectPage() method has failed for the page nr. " + i.ToString() + " with the status: " + gdpicturePDF.GetStat().ToString() + "\n";

            }

        }

        MessageBox.Show(message, caption);

    }

    else

    {

        if (status == GdPictureStatus.OK)

            MessageBox.Show("This file doesn't contain any page.", caption);

        else

            MessageBox.Show("The GetPageCount() method has failed with the status: " + status.ToString(), caption);

    }

}

else

    MessageBox.Show("The file can't be loaded.", caption);

gdpicturePDF.Dispose();
See Also