2006.11.08 17:11 "Re: [Tiff] Is there any image data in Custom IFD?", by Phil Harvey
According to the EXIF specification, the Interoperability IFD is the only IFD referenced from the EXIF IFD. The GPS IFD is referenced from IFD0.
thanks for the link of last conversation, Act last time i had asked about TIFFTAG_INTEROPERABILITYIFD, TIFFTAG_GPSIFD IFD's, as Phil Harvey said that TIFFTAG_INTEROPERABILITYIFD tag is part of EXIFIFD, but these tags are included in tiffFieldInfo of libtiff. So i am supposing that the above tags are part main image directory. Is there any possibilty that TIFFTAG_INTEROPERABILITYIFD and TIFFTAG_GPSIFD IFDs would be part of EXIFIFD??