XImage VRes Property. The vertical resolution of the current frame (DPI). ABCpdf .NET PDF Library. From ABCpdf .net previous page next page VRes Property Type Default Read Only Description [C#] double [Visual Basic] Double See description. Yes The vertical resolution of the current frame (DPI). Notes This property reflects the vertical resolution of the current frame. It is measured in dots per inch (DPI). Example None. previous page start next page