How can I place png data as a Key Value pair into an Annotation?

[Ryan]

I think this forum post is what you are looking for.

How to create a PDFNet Image object from a UIImage on iOS

Example from UIImage. The project’s PNG build settings aren’t important, because getting PNG data from a UIImage object is always in a standard PNG format. This also preserves transparency. PTElementBuilder* builder = [[PTElementBuilder alloc] init]; PTElementWriter* writer = [[PTElementWriter alloc] init]; PTPDFDoc* doc = [self.pdfViewCtrl GetDoc]; // will write image to page 1 PTPage* page = [doc GetPage:1]; [writer WriterBeginWithPage: page placement: e_ptoverlay page_coord_sys: YES co…

If the above doesn’t work for you, then please elaborate on the following.
What is the source of the PNG? Where does it come from?
Is loading the PNG from disk an option for you? If not, how come?