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

2006.04.19 21:52 "Re: [Tiff] PDF/A vs. TIFF", by Bob Friesenhahn

JBIG2 and JPEG2000 use patented algorithms so they are not as useful as they should be.

Patents, provided they are covered by "reasonable licensing" aren't considered a limiting factor in ISO standards. So that's a non-issue.

You didn't finish your sentance. I think you meant "So that's a non-issue for ISO standards". Patents are a huge issue to the world at large even if the licensing fee is "reasonable". The intention of patents is to intentionally restrict implementation and they have proven to be quite effective at that.

"bit rot" is NOT the issue for long term storage (at least on the file format side of the fence)....it is about the "ability to preserve information its presentation". Because TIFF (as we know it today) has been "hacked up" by many people for many (incompatible) purposes - not just with new and undocumented tags BUT also with variant implementations of existing tags (eg. OJPEG), it doesn't pass the test for reliability. Neither does "standard" PDF - which is why a SUBSET of the standard, now called PDF/A (or ISO 19005-1) exists - to remove any potential problems and "lock down" areas of ambiguitity.

Doing the same for TIFF would be a worthwhile goal...and one that would be necessary for TIFF to achieve a level of respect in the archival community.

So, if the original presentation is not bit-mapped raster and has metadata that TIFF does not support, then PDF/A will do better. The "first do no harm" principle applies.

Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/