2008.07.02 17:32 "[Tiff] BigTiff Support", by alexander johnson

2008.07.10 23:17 "Re: [Tiff] eta for bigtiff support?", by Bob Friesenhahn

There's still the open issue of the MIME type, which was discussed a while back and then dropped. As I read IETF RFC 3302 (http://www.ietf.org/rfc/rfc3302.txt), "image/tiff" is defined in terms of TIFF 6.0 conformity, so it would be incorrect to refer to a BigTIFF document as "image/tiff". IANA has also registered a MIME type "image/tiff-fx" for TIFF-FX, defined by RFC 3950, so it would be consistent to shoot for "image/tiff-big". IANA requires "publication by a formal standards body," though, so it would be more realistic to stake out "image/x-tiff-big".

This is closely related to the file extension issue. If the file extension used is similar to existing TIFF (as many here seem to prefer), then the only way to determine its type is by inspecting the file header.

Updated file formats do not always obtain new file extensions or MIME types. BMP, Postscript, and PDF are excellent examples of this.

My own inclination is to continue using the existing TIFF file extensions and TIFF MIME type and let the end applications and users figure things out. If users start having problems with opening files, then they will complain to their application vendor so that the updated format is supported.

If TIFF is defined by TIFF 6.0 conformity then many existing TIFF files do not conform. For example, JPEG compression in TIFF does not conform.

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