2005.09.28 00:49 "[Tiff] PSP libtiff hack?", by Frank Warmerdam

2005.10.20 12:34 "Re: [Tiff] Read EXIF Tag", by


Based on my experience, the TIFFTAG_EXIFIFD just provides the address of where the exif IFD is located in the file. It doesn't actually provide the entire exif blob. It would have been

better if it was more like the icc Profile tag which does return the
entire blob.

long value32;

if (TIFFGetField(m_TIFFHandle, TIFFTAG_EXIFIFD, &value32) == 1)
        // open the file in binary mode
        // read the tiff header to determine byte order
        // seek to "value32"
        // read and parse IFD at "value32";

Lou Sakey
KNET 27-67676

Chris Losinger <losinger@earthlink.net>
Sent by: tiff-bounces@lists.maptools.org
10/19/2005 09:47 PM

        To: tiff@lists.maptools.org
        Subject: [Tiff] Read EXIF Tag

i just dropped-in LibTiff v3.7.4, and i'm having trouble reading tag


     long *offset = 0;

     UINT16 count = 0;
 = TIFFGetField(tif, 0x8769, &count, &offset);BOOL bFound

yields bFound = 0

in 3.7.0, i had a _TIFFMergeFieldInfo extender setup that would grab that tag and a couple of others. now, i see that LibTiff has support for reading that tag natively, so i've disabled my extender, and am trying to read that tag the same way i'd read any other tag. but, it doesn't seem to grab it from my test TIFFs. (v3.7.0 with the extender does)

is there anything i need to do before trying to read that tag?

note that i'm not trying to parse the EXIF IFD with LibTiff (yet), i'm just trying to get the raw tag data.


smallest@smalleranimals.com http://www.smalleranimals.com