2007.01.15 15:42 "Re: [Tiff] TiffOpen opens file too long", by Joris Van Damme
I compiled libTiff 3.8.2 library for PocketPC platform, using Visual C++ 2005 compiler (with optimalization turned on). I use it to open quite large (about 12000x8000) black-and-white images. I noticed that TiffOpen spends about 2 seconds just opening the file and reading it's directory (reading and decoding stripes is much faster, so I think that it's not because of slow I/O or something like that). With option 'h' (read header only), TiffOpen returns almost immediately, so I suppose that it spends so much time on reading file's first directory. And here's my question - is it possible to speed up the execution of TiffOpen (including: opening the file and reading it's directory), in that case?
Just in case - images, which my program reads, are usually divided in stripes, each having height of about 30 pixels (so file consists of few hundred stripes).
Is it possible there are huge tags in there? Can you show us a tiffdump, tagdump, tag viewer dump, or anything that would allow us to correlate the problem with the particular TIFF features?
Joris Van Damme
Download your free TIFF tag viewer for windows here: