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Tiff image display wrong (tiff tags not interpreted) - Printable Version

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Tiff image display wrong (tiff tags not interpreted) - andife - 07-12-2018

Hello,

I created a tiff images in which there is a central "white line" (gimp_question3.tif).
Everything works fine with irfanview, imagej, the line of the color is display correctly.

Opening the file with gimp I got a black line, although the value is "0" and 
the Exif.Image.PhotometricInterpretation is "White is zero".

Is there no interpretation of this tag?

[attachment=1922]

What could be the problem? Some gimp autoconfiguration?
Default values for ICC profile?

Or is something wrong with the original tiff image?

Thank you

Andi

RE: Tiff image display wrong (tiff tags not interpreted) - rich2005 - 07-12-2018

Made with ImageJ and inverted using look-up-table (LUT) invert.

Gimp 2.8 opens inverted (with white stripe). A straight ImageMagick convert gets a 'vanilla' tif.

[Image: rAaXF6z.jpg]

Probably a bug in the way Gimp 2.10 handles tif's. ignores the inversion.

If you report it: https://gitlab.gnome.org/GNOME/gimp/issues/
Be sure to give all the details, how it was made, etc. I look at some of the 'bug' reports containing zero information other than this/that does not work and 'just wonder'

RE: Tiff image display wrong (tiff tags not interpreted) - andife - 07-12-2018

Hello, thank you for your answer.
I tried to reproduce what you were saying

Code:
user@pc1:~$ convert gimp_question3.tif gimp_question3_afterconvert.tif

user@pc1:~$ tiffinfo gimp_question3.tif 
TIFF Directory at offset 0x8 (8)
  Subfile Type: (0 = 0x0)
  Image Width: 3 Image Length: 9
  Resolution: 1200, 1200 pixels/inch
  Bits/Sample: 8
  Compression Scheme: None
  Photometric Interpretation: min-is-white
  Samples/Pixel: 1
  Rows/Strip: 9
  Planar Configuration: single image plane
  ImageDescription: ImageJ=1.52e
unit=inch

user@pc1:~$ tiffinfo gimp_question3_afterconvert.tif 
TIFF Directory at offset 0x24 (36)
  Image Width: 3 Image Length: 9
  Resolution: 1200, 1200 pixels/inch
  Bits/Sample: 8
  Compression Scheme: None
  Photometric Interpretation: min-is-black
  FillOrder: msb-to-lsb
  Orientation: row 0 top, col 0 lhs
  Samples/Pixel: 1
  Rows/Strip: 9
  Planar Configuration: single image plane
  Page Number: 0-1
  ImageDescription: ImageJ=1.52e
unit=inch

so the convert of imagemagick changes the "Photometric Interpretation".

But what does "Inverting LUT" mean? This is not a tiff-tag?

RE: Tiff image display wrong (tiff tags not interpreted) - Blighty - 07-12-2018

Gimp 2.8.22 : Opens with a white stripe
Gimp 2.10.2 : Opens with a black stripe

RE: Tiff image display wrong (tiff tags not interpreted) - andife - 07-12-2018

opened a bug report: https://gitlab.gnome.org/GNOME/gimp/issues/1838
If it is not a bug, I'm still interested in solving this proble and additional hints.

RE: Tiff image display wrong (tiff tags not interpreted) - rich2005 - 07-13-2018

(07-12-2018, 01:11 PM)andife Wrote: Hello, thank you for your answer.
I tried to reproduce what you were saying

so the convert of imagemagick changes the Photometric Interpretation".

But what does "Inverting LUT" mean? This is not a tiff-tag?

Looks like ImageMagick gives correct values.
Code:
identify -verbose gimp_question3.tif
is the original tiff:photometric: min-is-white converted gives min-is-black

From what I see in the Tiff specification

The “normal” PhotometricInterpretation is WhiteIsZero.
However, if the PhotometricInterpretation is BlackIsZero, the TIFF reader must reverse the
meaning of white and black when displaying and printing the image.

Which is what is required.

Not too sure what is correct now.
I do think you should have mentioned the image has an "inverted LUT" from ImageJ=1.52e in your bug report.