2005.01.21 15:14 "Re: [Tiff] deleting tags!", by Frank Warmerdam

I have had a really frustrating day trying to work out how to delete tags from a tiff header. Can anyone help me here? I am truly zero at c and am having a real 'mare trying to get anywhere. I have got as far as seeing that there is nothing special pupose for it in libtiff, so there is probably some way of doing it by undefining the tag. Any pointers?

Antione,

I'm not aware of any way of clearing a tag completely from the directory either. In fact, "in place" update of a TIFF file on disk is still a relatively experimental area. In the past before in-place update there was never a compelling need to delete tags from an in memory directory since you could update a file on disk (other than appending new images).

If you really need to do this for some specific purpose (and a specific tag), I'm sure we could help you with a hack going around the public interface.

The more conventional approach though is to copy the file you want to change to a new file, and just avoid copying anything you don't want in the new file.

Best regards,

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