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Problem: TIFF image displays with colors inverted

Solution or Workaround

How to correct a TIFF image that displays inverted colors.

Answer:

The 'PhotometricInterpretation' tag is set to a value other than 1.

The value 1 is recommended for bilevel and greyscale images in accordance with the Aldus TIFF 5.0 standard. If the tag is set properly before the TIFF file is created, then the colors are displayed normally. The PhotometricInterpretation tag should be set to a value of 1 with the software that was used to create the image.

For a black and white image ( 0's and 1's for values ), the image can be converted to grid using the IMAGEGRID command and inverted using the GRID syntax

newgrid = 1 - oldgrid

Greyscale images can also be converted to grids and inverted by subtracting the grid from the maximum possible value for the image (usually 255). For instance: newgrid = 255 - oldgrid

If no GRID license is available but a TIN license is available, a similar greyscale result can be accomplished as follows:

LATTICEOPERATE REPLACE oldgrid 255 tempgrid
LATTICEOPERATE SUBTRACT tempgrid oldgrid newgrid
KILL tempgrid ALL

Color images must be corrected when they are created.

Notes:

To obtain a full listing of the Version TIFF 5.0 specifications that ArcInfo follows, look under "Image Integration>Supported image formats>TIFF files" in the ArcInfo 7.x online documentation.