Scaling an Image

Scaling is an important requirement of image processing as it resizes (increases and decreases the size) image. Bitmap also allows scaling in and out an image through the InterpolationMode property of the Scaler class.

The image below shows scaling in and scaling out feature.

The following code illustrates scaling in and scaling out an image on button clicks. This example uses the sample created in the Quick start.

Visual Basic
C#

Visual Basic

Private Sub ApplyTransform(t As BaseTransform)
    Dim newBitmap = bitmap.Transform(t)
    bitmap.Dispose()
    bitmap = newBitmap
    UpdateImage()
End Sub

'Event to scale in the image on button click
Private Sub Button_Click_1(sender As Object, e As RoutedEventArgs)
    Dim px As Integer = CInt(bitmap.PixelWidth * 0.625F + 0.5F)
    Dim py As Integer = CInt(bitmap.PixelHeight * 0.625F + 0.5F)
    If px > 0 AndAlso py > 0 Then
        ApplyTransform(New Scaler(px, py, InterpolationMode.HighQualityCubic))
    End If
End Sub

'Event to scale out the image on button click
Private Sub Button_Click_2(sender As Object, e As RoutedEventArgs)
    Dim px As Integer = CInt(bitmap.PixelWidth * 1.6F + 0.5F)
    Dim py As Integer = CInt(bitmap.PixelHeight * 1.6F + 0.5F)
    ApplyTransform(New Scaler(px, py, InterpolationMode.HighQualityCubic))
End Sub

void ApplyTransform(BaseTransform t)
{
    var newBitmap = bitmap.Transform(t);
    bitmap.Dispose();
    bitmap = newBitmap;
    UpdateImage();
}

//Event to scale in the image on button click 
private void Button_Click_1(object sender, RoutedEventArgs e)
{
    int px = (int)(bitmap.PixelWidth * 0.625f + 0.5f);
    int py = (int)(bitmap.PixelHeight * 0.625f + 0.5f);
    if (px > 0 && py > 0)
    {
        ApplyTransform(new Scaler(px, py, InterpolationMode.HighQualityCubic));
    }
}

//Event to scale out the image on button click
private void Button_Click_2(object sender, RoutedEventArgs e)
{
    int px = (int)(bitmap.PixelWidth * 1.6f + 0.5f);
    int py = (int)(bitmap.PixelHeight * 1.6f + 0.5f);
    ApplyTransform(new Scaler(px, py, InterpolationMode.HighQualityCubic));
}