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Hi Tyn and Bas, I hope you are well and enjoying the winter season. I continue to get snow at my house here in the foothills of the Rockies above Boulder, Colorado. So far, I have received over 1.2 m of snow at my house! Now, down to business: Late last week and this past weekend I got serious about adding direct support for Unidata PNG-compressed images (both AREA and GINI) in McIDAS. The results of my effort are included in the gzipped tar file, mcupdate.tar.gz, that is attached to this note In order to implement the changes that I made, you need to do the following on the Linux workstation on which McIDAS-X v2006 is installed: <login as 'mcidas'> cd ~mcidas/mcidas2006/update -- copy the file that is attached, mcupdate.tar.gz, to this directory ./mcunpack cd ../src make make install NB: - it would be a _good_ idea if you backed up the files that will be replaced before running mcunpack from the ~mcidas/mcidas2006/update directory. Here is the list of files that will be overwritten: in ~mcidas/mcidas2006/src: CHANGES.2006 giniutil.c giniutil.h icget.for ispnghed_.c makefile rdtrka.for in ~mcidas/mcidas2006/data: VERSION.TXT - the updates are for the v2006 McIDAS distribution. Attempting to use them with any other version will have unknown results, but my feeling is that they would be _bad_ Bas, As you will see, I chose to _not_ modify mcread.c since it is _the_ general purpose file reading program in McIDAS. Instead, I created a new C file, arealine.c, that will check the type of the image to be read to determine if it is a PNG-compressed image. If it is not, it simply calls Mcread in the same way that lbi_ does. 'arealine' is called from the Fortran routine 'rdtrka' (located in rdtrka.for); it replaces the call that 'rdtrka' made to 'lbi_'. The change made to get the audit trail listing from IMGLIST (keyword sequence FORM=AUDIT) was much simplier, but it still required that one image file read be made from 'icget' (in icget.for) to determine if it the image in question is PNG-compressed. If you decide to load in the newly revised code (and I assume you will), please let me know your results. NB: I have not made the changes part of the official Unidata McIDAS-X distribution yet since I am still testing the routines that will be impacted by the mods), Last comment: My intention is to now seriously look at including support for wavelet-compressed METEOSAT imagery. I also intend to try and estimate the effort that it will take to add support for the vegetation images that Tyn inquired about earlier, but that is another Support Inquiry. How long it will take to add support for wavelet-compressed METEOSAT imagery is unknown... Cheers, Tom **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: HWT-941133 Department: Support McIDAS Priority: Normal Status: Closed