2010.11.29 16:50 "[Tiff] libtiff documentation, about Exif IFD pointer, some examples?", by Johan Simonsson

2010.12.01 15:07 "Re: [Tiff] libtiff documentation, about Exif IFD pointer, some examples?", by Johan Simonsson

Hi

To clarify the question.

Can libtiff create a new "private" IFD for EXIF IFD?

Today it looks like the libtiff only can read the EXIF IFD (with TIFFReadEXIFDirectory),

but he can't create a new one.

I looks like functions like TIFFCreateDirectory only can create IFD that will become part of the linked list of IFD:s.

Thanks
Johan

On 11/29/2010 06:00 PM, tiff-request@lists.maptools.org wrote:

I'm trying to figure out how to use libtiff in a correct way. The basic stuff like reading and writing some of the basic tiff tags (in IFD zero) with TIFFSetField and TIFFGetField is kind of strait forward.

But then when it comes to reading and writing more "advanced" tags in let's say the Exif IFD that is pointed out by the Exif IFD Pointer (34665 / 0x8769) things is getting a little bit more complicated. There are some special functions for this and the tags are specified in the header files. But I can't really find any examples on how to use them. Or how to create a new Exif IFD, and update the Exif IFD Pointer with the correct value.

Another example is how to get all tags in a file, without using a lot of TIFFGetField. I got the feeling that you could list the content in the current IFD but not really how that could be done.

I have tried to search this list for links to some relevant documentation, but not really found any.

So I would be really grateful if someone could give me some pointers either on how to solve the above questions or where to find the relevant documentation.