I have an MS-Word document with black text on a white background. When I print it with PDFCreator 1.2.0 this results in a transparent PDF - which is exactly what I want. (The fact that the PDF is transparent is obvious when I add a background image to it using PDFTK.)
However I also have a PNG file which has a black image on a transparent white background, and when I open the file using Irfan View and print it using PDFCreator, I end up with an opaque PDF - which is *not* what I want. (My PNG file uses indexed color; index entry #0 is white and has an alpha value 0; entry #1 is black; the background color is index entry #0.)
Is it possible to create a transparent PDF from a PNG file using PDFCreator? And if so, what format should the PNG file be in? And does it matter what application I open the PNG with before printing (e.g. IE, Firefox, Irfan View....)? And what settings do I need to use in PDFCreator?