+This document describes the changes made to the software between the +previous and current versions (see above). +If you don't find something listed here, then it was not done in this +timeframe, or it was not considered important enough to be mentioned. +The following information is located here: +
++The ChangeLog will follow, but please note the most important change: +LZW compression has been removed. +
+Unisys has the patent on LZW compression and have been very active in +their enforcement of late, demanding payments of $5000 or more from +websites using unlicensed software to create GIF's. They could well +do the same do persons using libtiff to create LZW compressed TIFF +images. +
+From Burn All GIF's Day:
+
+The catch is that it appears to be difficult or impossible to get a
+Unisys license to use LZW in free software that complies with the Open
+Source Definition
+
+Unfortunatly, the removal of LZW compression means that saved image size has +grown dramatically. Without a change in the TIFF spec to support +another lossless compression format, this is unavoidable. +
+The library can use zip for lossless compression, but as this is not +part of the spec, TIFFs using zip compression may not work with other +software +
+We will be making a patch available that will contain the LZW +compression code for users who have either obtained a license from +Unisys or are willing to risk it. +
+LZW decompression is unchanged. +
+
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