[DVIPDFMx] changing PDF default to 1.5

[Matthias Franz]

On Sat, Dec 05, 2009 at 12:34:20AM +0000, Karl Berry wrote:
> So that's the question: is it safe and a good idea to have pdftex and
> luatex output 1.5 by default, with object compression turned on?

As you mentioned, the file size difference can indeed be significant,
in particular if the document contains many hyperlinks.

On the other hand, there are still some users out there with old PDF
readers unable to read PDF 1.5. Hence for documents that should be
readable under all circumstances (think of job applications or grant
applications), PDF 1.5 is not a good idea. Setting the default to 1.5
is therefore somewhat risky because users might not be aware of this
issue.

A minor point: pdfinfo and pdffonts are ridiculously slow for large
PDF 1.5 documents. Pdfinfo has to read just a couple of PDF objects,
yet it needs for that about 30 times longer than dvipdfmx needs to
include all pages of the same document into a new PDF file.

Best,
-- 
Matthias