About editing PDF image files
You can use PaperPort’s image editing tools to enhance PDF Image files.
PaperPort uses 
as the file type icon to indicate that you can image edit a PDF file in the Image View window.
PDF Formatted Text & Graphics (Normal PDF) files — and other PDF files that PaperPort recognizes as text items rather than image items — can be edited in programs that support this format, such as Nuance PDF Viewer Plus or PDF Converter Professional.
The file type icon 
(or the icon currently associated with the program you use to open PDF files) indicates that the PDF file is editable outside of PaperPort.
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