PdfImageRenderInfoBoundingBox Property

The axis-aligned bounding rectangle of the rendered image, or of its first part when the image continues on the next pages, in points and relative to the top left corner of the content area of the page in a document, of the page in an edited document or of the template. For rotated images this is the smallest axis-aligned rectangle that fully contains the rendered shape

public PdfRectangleF BoundingBox { get; }