Blank/Unreadable Pdfs?

[MarjaE]

A lot of Internet Archive pdfs either show up as blank pages, or as black-and-white pages with the scanner's watermark covering up the page.

And in my experience the corresponding djvus do not load.

Any solutions?

P.S. Just got two of the corresponding djvus to load. I'll see how this goes.

[dwig]

I've had issues with some of the IA's PDFs where they would display fine in Acrobat Reader on a PC but were blank or mostly blank when viewed on my Kindle 3. I seems that the "evil" PDFs used layers and transparency to display the text over a bitmap of a scanned paper page.

I fixed these rather reliably using a PDF virtual printer, usually PrimoPDF, installed on my Windows machine. There are several out there. These install as a printer but send a PDF file to disk instead of printing to an actual printer. The PDF files that these create are simple flat files with no layers or transparency and were always compatible with my Kindle. Mac OSX has a similar function built in which should work as well, though I haven't tried it for this particular problem.

With the virtual printer all you need to do is open the PDF on a computer with software that can display the file correctly (e.g. Acrobat Reader which always worked for me) and print to the virtual printer. The resulting PDF file is usually much smaller and being a flattened file is compatible with almost all PDF reading software.

[MarjaE]

In my experience, in OS X, the resulting pdf files tend to bloat, often to more than twice their original size.

Or this last time, more than a hundred times, going from 21 mb to 2.68 gb.