2006.04.19 10:45 "[Tiff] TIFF + Group4 will last 10 years?", by Rui Castro

2006.04.19 21:03 "Re: [Tiff] PDF/A vs. TIFF", by Leonard Rosenthol

I'd rather ask, why use PDF/A?

Because it's a PUBLISHED, SUPPORTED and DOCUMENTED international standard. While TIFF (regardless of the excellent work of Chris Cox and this group) remains a privately held/controlled and (not completely) documented specification.

It's at least an order of magnitude more complex than TIFF,

Actually, starting from scratch - I'd say it's a toss up.

And there are enough excellent open source libraries for PDF in your choice of languages just as there is for TIFF.

So again, I'd dispute that.

to no benefit, particularly for mononcrome images (unless you need to include searchable text or embed arbitrary metadata in your image file).

MUCH smaller file sizes courtesy of JBIG2! And the possibility of JPEG2000 for color images. PLUS, the ability to do "image segmentation" to use the optimal compression for each component of a multi-element page (eg. text vs. pictures on a newspaper page).

And, as you note, such (pretty) important things as searchable text and metadata.

PDF/A is new, relatively unproven, and exists to solve problems with PDF as an archive format.

Actually, it exists to solve the problem of archiving ANY electronic data - SPECIFICALLY as an replacement for TIFF in places such as the National Archives, US Court system, etc. They were the biggest proponents and supporters of PDF/A from the beginning. And many places are no longer accepting TIFF files - and if they are, the first thing they do is convert it to PDF.

Don't get me wrong - TIFF serves a variety of purposes, but long time archival storage is NOT one of them.

If you were to invent an extension to TIFF called "TIFF/A", to add functionality that PDF/A has and TIFF lacks, what would you add and how?

The main advantage over PDF/A over PDF for archival storage is that it is a RESTRICTED SUBSET that is VERY tightly controlled. The most IMPORTANT thing you could do with TIFF/A would be to do the same. Remove/disallow anything that is ambigious...


Leonard Rosenthol <mailto:leonardr@pdfsages.com>
Chief Technical Officer <http://www.pdfsages.com>
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