1999.08.14 14:40 "Re: Problem in compression LZW : produce a .TIF that crash Paint Shop Pro 5", by Helge Blischke

OK, I resend the file. How do you check it?

I looked at the image and found the following:

1. it is LZW compressed, and the predictor value is 2, what means horizontal differencing - as opposed to what you stated above.
2. The resolution unit is specified, but neither X nor Y resolution is given. Many apps default the resolution to 72 dpi if not or not sufficiently specified, but it may be your app(s) barf on it.
3. The image is divided in many many tiny strips. It might be the application cannot cope with strips or tiles.

Apart from these comments, the TIFF file conformes to the spec and is perfectly decodable.

Try to make a copy using tiffcp (one of the utilities that come with libtiff):

tiffcp -c lzw -r number old.tif new.tif

where number is at least the image length (in pixels). This will make a copy with predictor value 1 (no differencing) and make the image consist of only one large strip, and let us know if it wors then.

He|ge

H.Blischke@srz-berlin.de
H.Blischke@srz-berlin.com
H.Blischke@acm.org