davis@groucho.ucar.edu (Glenn P. Davis) (08/29/89)
Hi. I am creating TIFF on a sun3 files using a library I obtained from via ftp from ucbarpa.berkeley.edu: tiff.tar.Z. I'll call this the PD (public domain?) library. The TIFF files output I'm outputing and those created by NIH 'Image' are inconsistant and I'm trying to track down what is wrong. In 'Image', suppose I read in an 8 bit greyscale image using the import/offset facilty. It looks fine. I 'Save As' as a tiff file. I can open this file again in 'Image', and it looks fine. I can move it to a NeXT computer, look at it with a utility there, looks fine. EG, this is a good tiff file. There is a command called 'tiffinfo' included in the PD library. It's output looks like this: NIHarea0120.tiff: Warning, ignoring unknown field with tag 43314 (0xa932). TIFF Directory at offset 0x8 Image Width: 640 Image Length: 350 Bits/Sample: 8 Compression Scheme: none Photometric Interpretation: "min-is-white" Planar Configuration: single image plane Which is reasonable, given the fact that NIH Image has a "program unique" field in the tiff file. When I use 'tiffinfo -d' to dump the pixel image, however, I get all zeros for the image data. Obviously, at this point I'm supicious of my PD tiff library. When I create a TIFF file using the PD library, I can't import it the NeXT. When I import it into NIH 'Image', It doesn't look like anything. 'tiffinfo' of it yeilds: TIFF Directory at offset 0x36b08 Image Width: 640 Image Length: 350 Bits/Sample: 8 Compression Scheme: none Photometric Interpretation: "min-is-white" Planar Configuration: single image plane Which is also reasonable. (They put the directory at the end). 'tiffinfo -d' gives me the right image data, so libtiff.a is at least idempotent. So, the situation is, I have three systems which supposedly read/write a "standard" format file. Two of them agree on the thin set I'm testing. Is the libtiff.a from ucbarpa.berkeley.edu wrong? Can the authors of the PD library be drawn out of hiding? The SCCS id's contain the word "Pixar". Glenn P. Davis davis@unidata.ucar.edu UCAR / Unidata PO Box 3000 1685 38th St. Boulder, CO 80307-3000 Boulder, CO 80301 (303) 497 8643