2006.01.22 23:55 "[Tiff] LibTIff and Photoshop TIFF support (Multipage TIffs)", by Jeet Shroff
i was currently working on using LibTIffs to import and export tiff files and am interested in getting this working with TIFFS that are generated using Photoshop.
Basically i am interested in gaining access to the layered data that you can store in Photoshop TIFFS. This layered data is stored in Tag number 37724 (ImageSourceData tag) and is not recognized by LibTiff. Through the posts in the mailing list I have seen that LibTiff just throws a warning when it reaches this tag and does not know what to do. Has anyone got this working, as in successfully able to read in the layered data that is stored in the TIFFs from Photoshop using LibTiff?
If there is no easy access using the LibTiff interface, is there a way to gain access to that tag and have it read in and then I can manipulate and traverse to that data in the file myself and deal with it accordingly then. But how do I gain access to that tag, since LibTiff keeps on saying it's undefined or private. I can extend it, but the actual Tag is not clearly defined, as in it could be any size, and i'm not sure how I can use LibTiff to get this data or even the beginning of where this layered data could be located.
Also -- where can I generate or gain access to multi-page tiffs? I don't any program that can generate Tiffs like that for me. I've tried know
Photoshop and GIMP. Does anyone have regular non-layered multi-page TIFFs that have 2 or more images stored in them and so we can use the SetDirectory and ReadDirectory functions in LibTiff to gain access to the different image data for those images?
Any help with this will be highly appreciated.