Preview corrupts PDF documents when saving
There appears to be a serious bug in Preview and/or OS X's PDF creation libraries, that causes PDFs to be "invisibly" corrupted.
My situation is: I have a number of PDFs that have been created using Windows-based OCR software. They are standard PDF/A documents, and when I open them in Preview they display fine. More importantly, I can "copy" the text from the document to the clipboard and it works as you would expect.
However, if the PDF document it edited in any way - page order changed, a page from another document moved into the document etc - and then saved, the resulting PDF is corrupt. Although the text appears on the screen normally, any text copied to the clipboard is garbled: for example, the displayed text:
AUTUMN SPECIAL!
appears in one of my documents. However, highlighting it and copying it results in
*)﴿*%&(﴾'"!# $
in the clipboard.
I now have hundreds of documents that are effectively useless, as I cannot accurately copy the document text. I know others have had the same issue (see the posts in this Superuser.com thread for examples). The issue would appear to go as far back as Lion and possibly before then.
Is this a "known issue"? And has anyone come up with work-arounds - other than re-OCRing the files (usually by exporting as TIFFs, reOCRing etc)?
Mac Pro (Early 2009), OS X Mountain Lion (10.8.2)
