Can I get better PDF quality in 4.5.x?

[tcvw]

I have a QTextDocument that contains many QImages (saved as resources). When I save this document out as a PDF I am getting poor quality. Here is what I am doing to save the PDF:

QPrinter printer(QPrinter::HighResolution);
printer.setOutputFileName(path);
printer.setOutputFormat(QPrinter::PdfFormat);
text_m->document()->print(&printer);

QPrinter printer(QPrinter::HighResolution);
printer.setOutputFileName(path);
printer.setOutputFormat(QPrinter::PdfFormat);
text_m->document()->print(&printer);

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The resulting PDF has poor quality especially for the images. Higher contrast edges are emphasized and even the words in the text are aliased to some degree.

Does anybody know a way to increase the fidelity of the rendered PDF so it matches the quality of what is displayed on the screen?