PDFsharp & MigraDoc Foundation

Hello!
When i use
Dim page As New PdfPage()
Dim image As XImage = XImage.FromGdiPlusImage(timage)
Dim maxsize As Integer = Math.Max(w, h)
page.Width = timage.Width
page.Height = timage.Height
mydoc.Pages.Add(page)
Dim xgr As XGraphics = XGraphics.FromPdfPage(mydoc.Pages(mydoc.Pages.Count - 1))
xgr.DrawImage(image, 0, 0, timage.Width, timage.Height)
xgr.Dispose()
timage.Dispose()
The document that I create it is ok, but the page with a big image (5000x20000) is correctly dimesioned, but is blank....
The image is jpg. With tif function.
Hav an idea?
Thanks a lot

Are page.Width and page.Height the same units as timage.Width and timage.Height?
Is, for example, the latter in pixels and the former in points?

(Also, you failed to declare timage in that snippet.)