2012.11.27 03:25 "Re: [Tiff] help writing thumbnails to TIFF file?", by Bob Friesenhahn
On Mon, 26 Nov 2012, Paul Heckbert wrote:
PS: If we're interested in distant history, I worked with Sam Leffler at Pixar in 1986 and he and I wrote the Pixar Software Standards document together.
And Graphics Gems, and zoom, and...
I wonder if others have attempted to write two directories (IFDs) using TIFFCheckpointDirectory. Anyone got pointers to code that does this? Am I using TIFFSetDirectory properly?
My current hypothesis: TIFFCheckpointDirectory works fine if you're writing only one directory, but it's buggy when there are multiple directories.
I expect that you are right that multiple directories does not work and it was not anticipated. Libtiff provides source code so a well-tested patch which gets it to work as you like is useful and appreciated. Of course the patch should not break other functionality.
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/