Specifies the bleed box defining the region to which the contents of the page shall be clipped when output in a production environment.
The bleed box may include extra bleed area that is required to accommodate the physical limitations of specific cutting, folding and trimming equipment.
The actual printed page may include printing marks that fall outside the bleed box.
The default setting is the page's PdfPageTreeObject.CropBox value.
The PDF page unit of measurement is points, which measures 1/72 of an inch (0.3528 mm). You can convert this unit of measurement, e.g., to pixels using the Units.PointsToPixelsF method.