[tex-live] [pdftex] PDF 1.5 by default in TL 2010

[Élie Roux]

2010/1/13 Thierry Bouche <Thierry.Bouche at ujf-grenoble.fr>:
>
> Not on the same machine! installing newer versions of AR implies
> uninstalling old versions even of AA (if I understood correctly the
> acronyms used by Phil...).

I have AR 9 and AR 5 on the same machine, I guess it's possible to
have AA 5 too... did you try?

> Anyway, this is really a tiny detail. What is less tiny is the content
> of the files distributed. In PDF 1.4, the internal structure of the
> PDF tree is more or less transparent, so that any viewer supporting
> PDF 1.0 can understand the file and display what it supports (the HTML
> viewer philosophy, more or less), and just leave apart some objects
> that are not understood. If you have so many annotations and objects
> that this structure represents heavy weight overheads, then you could
> just gzip your PDF file that would still be compatible with the
> world. (Maybe not elegant, but efficient). If you produce a PDF file
> where all this structure (which is verbose text) is compressed, then
> the content of the file is just inaccessible to any third party parser
> which has not been updated for PDF 1.5 (remember that people might be
> interested not only in viewing or printing PDF, but also reading it
> aloud for blind people, extracting metadata, converting textual
> content to some XML dialect: it's not only acrobat replacements whose
> compatibility have to be evaluated before such a move!).

When you build a software dealing with PDFs, you don't just read the
PDF character by character and do things according to the character
you see with a spaghetti code, you rely on a PDF library, and they all
can read PDF 1.5 when they are in a recent version, so I don't really
see your point here...

> It is funny to observe that while the trend for the ubiquitous format
> like XML (do you see a strong demand for compressed SVG?) is to have
> hyper-verbose uncompressed representation of content, we should care
> so much about the size of PDF files.

SVG can be compressed, I don't know if it is most of the time though...

> I've been told that most text
> file transfer over the networks are compressed on the fly by the
> routers (?) so that the actual impact on bandwidth might be zero.

Aouch !!! You've been told wrong, doing such a thing is totally
impossible. Which protocol are you talking about exactly? an IP router
deals with IP, it is already a humongous work for a router to make a
packet go from one place to another through the good pipe and most are
overloaded, deep inpection of the packet to see if it could be some
bits shorter is just absurd... I never heard such a rumor, it's quite
funny though :-)

Thank you,
-- 
Elie