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c#.netwindowsprintersspool

Spool - Microsoft Print to PDF, Microsoft XPS Document Writer - Error in converting SPL file to Images

I'm trying to convert the spool files to pdf? Do we have any options for this process to do?

I have a answer from forum as well. Do we have any work around?

Forum link: https://learn.microsoft.com/en-us/answers/questions/1179164/spool-microsoft-print-to-pdf-microsoft-xps-documen

Solution

  • "Spool Files".spl are printing components in transit from a "Print Driver" to a "Printer Device Port" such as virtual file.prn. Thus are not a single constant format.

    The samples from quote https://learn.microsoft.com/en-us/answers/questions/1179166/spool-microsoft-print-to-pdf-microsoft-xps-documen are two zipped files intended for file save as XPS. Thus are XPS format "in transit" when file saved as XPS (if complete) they should work in an XPS viewer.

    As XPS they are simply made of text "pieces" of XML. I did not notice any images in either sample. However that is also possible as XML can embed pieces of images, often such files can include a low res thumbnail.

    In many cases the images (PNG or JPEG) are severely spliced in a page, since that is what spooling is all about (dribbling big data to endpoint).

    Since the whole point of spool to PDF is to avoid saving before completion, it is easiest for print system to save the "Print to PDF" file after spooling (several .spl can = 1 .prn). Especially since you can specify the target port print to filename before start of spooling anyway.