Problems with Tiff-tags

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Hello everybody,

I have a problem concerning the tiff tags in the IFD.
I need to write a multiimage tiff stack to disk to
proceed in another program. As this program interprets
the resolutionX/Y tags for image scaling and Igor sets
this parameters to zero the program get a zero division
and closes. I tried to overwrite the tags with a tag list
excluded out of another tiff with exactly the same properties.
But Igor says I cant overwrite primary tags. Also every
modify image or changing the scaling doesnt lead Igor
to placing the write resolution tag values. Always only
zero. So what can I do to get the resolution tags with
some other value than zero by using the Imagesave function
or a function prior to it.
Thanks for your help folks.
Greetings Andy
The solution to this problem is to use the new /SRTG flag in ImageSave. This is a new feature available in IP 6.1.

This question has been answered on the IGOR mailing list.


A.G.
WaveMetrics, Inc.

March 20, 2008 at 01:27 pm - Permalink

ag wrote:
The solution to this problem is to use the new /SRTG flag in ImageSave. This is a new feature available in IP 6.1.

This question has been answered on the IGOR mailing list.


I maybe missing something, but after a day of hunting I just have to ask. I cannot find any mention of this problem in the mailing list, in particular there were no references found to the /SRTG flag.

Additionally, I wonder if there is a comprehensive list of Tag Descriptions which are recognized by Igor? Is it possible to append to that list for use with Tags 60000-65535 (allocated for internal reuse in the TIFF specification) or other TIFF extensions which are currently not recognized by Igor?

G. D.
IP 6.37 on Windows 7

January 13, 2017 at 03:12 pm - Permalink

Hello GD,

First, a special award for being able to dig something from that far in the historical record. :)
gusdemann wrote:

I maybe missing something, but after a day of hunting I just have to ask. I cannot find any mention of this problem in the mailing list, in particular there were no references found to the /SRTG flag.



For the record, this flag, which is still supported in some places, skips writing the built-in resolution tags so the IFD generated by Igor has 2 fewer tags. The two tags are Tag 282 and Tag 283 (XRESOLUTION and YRESOLUTION).

Quote:

Additionally, I wonder if there is a comprehensive list of Tag Descriptions which are recognized by Igor? Is it possible to append to that list for use with Tags 60000-65535 (allocated for internal reuse in the TIFF specification) or other TIFF extensions which are currently not recognized by Igor?
G. D.
IP 6.37 on Windows 7


Igor 6.37 is old; we have been shipping Igor Pro 7 since July of last year. IP7 uses LibTIFF to read images. Image writing is still a mixed bag.

In general Igor reads all the baseline tags. Tags in the range 60000-65535 are not in the baseline tags and are not read by most standard TIFF readers. If you are trying to write images with private tags you might want to try ImageSave with the /WT flag. See also ImageLoad with /RAT flag.

A.G.

January 13, 2017 at 04:22 pm - Permalink