IDL license file and GIF/LZW Patent Expiration

Topic:

Updated policy regarding GIF/LZW functionality in ITT products and license files (updated 1 May, 2006).Discussion:
You may notice in newer IDL license.dat files that the idl_tifflzw and idl_gif lines no longer appear. For IDL 6.1 and ENVI 4.1and later, IDL program GIF and TIFF-LZW functionality does not require the presence of the license features for:
   
    idl_gif
and
    idl_tifflzw

For example:

   INCREMENT idl_gif idl_lmgrd 1.000 1-jan-0000 uncounted \
      ABCDXXXXXXXXXXXXXXXX VENDOR_STRING="000011Acme, Inc." \
      HOSTID=00001234abcd PLATFORMS=i86_n ck=xx
   INCREMENT idl_tifflzw idl_lmgrd 1.000 1-jan-0000 uncounted \
      ABCDXXXXXXXXXXXXXXXX VENDOR_STRING="000011Acme, Inc." \
      HOSTID=00001234abcd PLATFORMS=i86_n ck=xx

Previous version IDL and ENVI licensing:

The presence of such INCREMENT lines are required only when using GIF and TIFF-LZW functionality with IDL versions 5.4 through 6.0 and ENVI versions 3.4 through 4.0. If required, contact ITT Technical Support or your local distributor to have "idl_gif" and "idl_tifflzw" added to your license file. Note that the presence of the license features have no effect in other versions of IDL or ENVI.


For additional information, please see the announcement from Unisys below. Thank you very much for your patience regarding our legal requirement to honor patent-restricted usage of GIF/LZW.

Unisys U.S. LZW Patent No. 4,558,302 expired on June 20, 2003, the counterpart patents in the United Kingdom, France, Germany and Italy expired on June 18, 2004, the Japanese counterpart patents expired on June 20, 2004 and the counterpart Canadian patent expired on July 7, 2004.