TOPIC:

I use "document.OpenMem".

I follow the sample that U suggest me.

yes, that is the problem.
Document.OpenMem() is readonly.

I have a byte[], from db internal storage, how I do to open a PDF in writable mode?

Now it's clear.
PDF loaded in byte[] aren't writable (after modification the size would change and it would rise to a memory exception).
You should use a stream or a temporary file: the second is much simpler.

Ok thanks now I can see the image (not during the zooming).
I doesn't understand the Matrix parameters for positioning correctly my image in x, y point of PDF, can U help me?

Ok I understand, the matrix parameters use. Thanks in advance

Only one more thing, I use PDFPageView for renderise pdf like your sample, I have to find the way to refresh the page after insert a image.

Now I can view the inserted image only after zooming action and during the zooming action the image was hidden.

How to refresh page and view image during zooming action?