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Hi again Carolina, After some more searching, I found that we still have a MODIS package on our anonymous FTP server: machine: ftp.unidata.ucar.edu user: anonymous pass: address@hidden directory: pub/mcidas/contrib file: modis_l1b.tar.gz Here are the comments from a previous email about the code in this package: >I have been temporarily pulled away from the MODIS project to work on >another high priority project since May 2004. Even the latest version of >the MODIS remap software is more than one year old. There were some >improvements being made to the software after I provided the decoders to >Dave. >We implemented the polar Stereographic projection remapping >program for the granules over the north polar region for the 1KM res L1B >(MOD021KM, and MYD021KM); and added the calibration block to the >remapped McIDAS multi-band AREA. For the 500m and 250m resolution L1B >data, the remap programs are pretty the same as before. As I mentioned >to Dave, the software is still under development and at its testing >stage. Currently, there is no document for the software. For a general >description on how the MODIS granules are re-projected and how the >bow-tie effect is corrected, please see my previous e-mail to Dave Santek. ... >I also include the >Makefile for the two remapping decoders. I used the HDF library with in >the McIDAS package. >Again, the code is not fully developed. Because some settings are hard >coded, the software will need to be modified before it can be run on >other system. >Aiwu The e-mail to Dave Santek that Aiwu is referring to is (note the date): >>Hi, Dave, >> >>I have put the MODIS L1B HDF decoders on our anonymous ftp server >>(ftp://gp16.www.noaa.gov) under directory /pub/modis. The tar file >>includes 3 decoders for L1B data at 1KM, HKM, and QKM resolution, some >>driver scripts for the our local remapping processing, as well as 3 >>sample AREA files at different resolutions and GIF images. I have >>written a short compile script for compiling the 3 decoders using HDF >>library within McIDAS. We will keep at least 3 days on the server. >> >>Currently, we only remap/correct L1B data from SSEC MODIS realtime >>system. This is mainly because SSEC provides data in a more timely >>manner and the granules are generally longer than 5-minutes. Our >>customers ( Fire analysis, OSEI ) prefers SSEC's data. The remapped >>region is limited to CONUS (22N-53N, 125W-65W). The code can be easily >>modified to apply to global data. The output AREA file is in >>Rectilinear projection. Passes over the polar region are skipped. >> >>The 3 remappers/decoders are logically very similar. Since the bow-tie >>effect is caused by the over sampling of multi-scans between adjacent >>frames, to get ride of it, one possible is to remap the pass. What I am >>doing in the decoders is to use geolocation at 1km to interpolate into >>500m and 250m for HKM and QKM data, grid the raw data into an array by >>embedding each pixel using its lat/lon. Since resolution gets lower as >>it approaches the edges, patchy edge problem arises after the gridding. >>To fix the the problem, simple 1-D interpolation, extrapolation, >>nearest neighborhood filling are used to fill the holes. As you could >>image, it is quite CPU consuming. Base on our user's interest, only >>selected bands are remapped: 8 bands( 1-4,6,22,31) at 1KM, 4 bands(1-4) >>at HKM, and 2 bands(1-2) at QKM. >> >>The software is still under development. Although it is >>semi-operational on our system, you may still see certain bugs in the >>code. For example, in the remapped images, there are some navigation >>problem( appears as boundary off 2 pixels near the edges). The PS >>remap/decoders for 1km and hkm are almost done. Since this project is >>still at its preliminary stage,we have no documents yet. To make the >>code more readable, I have taken out some debug statements, added some >>comment lines in the program. Attached are 2 sample images( Chesapeake >>Bay, and Albemarle Sound) generated from 250m raw data and remapped >>data. >> >>I don't mind at all that the software to be used by others. So, this code may or may not be helpful. Best of luck! 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: QJI-536086 Department: Support McIDAS Priority: Normal Status: Closed