There is more than one way to deal with this, unfortunately it's all quite messy. But it is possible. One is to use Inkscape to layer the image as an OCG, the

There is more than one way to deal with this, unfortunately it's all quite messy. But it is possible. One is to use Inkscape to layer the image as an OCG, the other is to treat the image as a "watermark" (which is really just another layer) with your image via PyPDF2 or similar.