Dim bmp As New Bitmap("c:\aa.gif")
Dim newBMPx As Integer
Dim newBMPy As Integer
If bmp.Width > 550 Then
newBMPx = 550
Else
newBMPx = bmp.Width
End If

If bmp.Height > 100 Then
newBMPy = 100
Else
newBMPy = bmp.Height
End If

PictureBox_LOGO.Size = New Size(newBMPx, newBMPy)
Try
PictureBox_LOGO.BackgroundImage = Image.FromFile("c:\aa.gif")
Catch ex As Exception

End Try