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Re: Upload to Ground



Jeff Lodoen <jmlodoen@thegrid.net> writes:
> I wonder if he's thinking PDF files are like PostScript
> files. I believe PDF is a descendant of PostScript but
> I doubt it's still 7-bit text.

PDF files *can* be 7-bit text only, and in fact the earliest PDF spec
required that.  Any binary data had to be encoded as text, using one of
several provided encoding schemes ("filters").  But a later PDF spec
added the ability to pass through binary data without encoding.  The
PDF spec recommends (but does not require) that in a comment on the
first "line" of the PDF file, there be some binary bytes with the
high bit set, as a flag to PDF-processing software that the file
contains raw binary.

These days it's probably pretty rare to see a PDF file that does not
contain any raw binary, but it's still possible.

Eric