Draw 4.0: Loading TIFF image: unsupported tiff image depth

PROBLEM

Loading a 24 bit TIFF image into IslandDraw 4.0 fails with the following error message:

file format is not correct: unsupported tiff image depth

In this case, the user had converted a JPEG image to TIFF with the xv image utility. She didn't realize that she had generated a 24 bit TIFF file. Attempting to import this image into Draw resulted in the error message above.

SOLUTION

The reason for this is that Island applications currently can only handle manipulating and displaying 8 bit color images.

Note that IslandPaint offers two TIFF file formats:

TIFF
TIFF 24-bit

The TIFF filter handles only 8 bit images. To load a 24 bit TIFF, use the "TIFF 24 bit" file format. Using this format results in calling a filter which will convert the 24 bit TIFF to 8 bit via a color dithering algorithm. The loaded image can then be exported to IslandDraw.

Note: IslandPaint 4.1 (from IPS 6.0) has full 24 bit color support.