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>From: Christian Page <address@hidden> >Organization: Universite du Quebec a Montreal >Keywords: 200106070835.f578Zop28356 McIDAS ADDE IMGCOPY IMGREMAP Christian, re: resampling images to 8-bit >Ok. So, could you give me an example of this? >I want to resample them to 8-bit (oversampled), The command to look at here is IMGCOPY. The conversion from 2-byte to 1-byte data is controlled by the STYpe= keyword: HELP IMGCOPY IMGCOPY -- Copies image data from a server IMGCOPY sdataset ddataset <keywords> Parameters: sdataset | source ADDE dataset name and position; specify as alias.position or group/descriptor.position; to use default position, either enter "0" or omit .position portion (no def for alias or group/descriptor, def=0 for position) ddataset | destination ADDE dataset name and position; specify as alias.position or group/descriptor.position; only positive integers (absolute positions) or the default are valid for the position number; to use the default position, omit the .position portion (no def for alias or group/descriptor, for position def=the position following the most recent image) Keywords: ********************* Image Positioning Keywords *********************** ... STYpe=VISR | reduces 2-byte data to 1-byte brightness data; not valid with BAND=ALL or SIZE=ALL ... So, let's assume you FTP the 2-byte data to your machine and then create an ADDE dataset to hold it. For sake of argument, let's call this first dataset GE-2B, and it has three descriptors: GE-2B/VIS GE-2B/IR GE-2B/WV Now, you have already setup another dataset called MYDATA (previous email) in which there is a descriptor IMAGES. This group/descriptor set was defined to include all possible images in AREA file format that are named using AREA file naming conventions. This dataset will automatically have the AREA files in the Unidata McIDAS-X distribution in them. For instance, listing the information for images 9000 - 9020 should result in a list that looks like (the listing migh have more): IMGLIST MYDATA/IMAGES.ALL Image file directory listing for:MYDATA/IMAGES Pos Satellite/ Date Time Center Band(s) sensor Lat Lon --- ------------- ------------ -------- ---- ---- ------------ 9010 TOPOGRAPHY 1 JAN 96001 00:00:00 40 105 1 9011 TOPOGRAPHY 1 JAN 96001 00:00:00 45 105 1 9012 TOPOGRAPHY 1 JAN 96001 00:00:00 0 100 1 9013 TOPOGRAPHY 1 JAN 96001 00:00:00 -90 105 1 9014 TOPOGRAPHY 1 JAN 96001 00:00:00 90 105 1 9015 TOPOGRAPHY 1 JAN 96001 00:00:00 0 0 1 9016 TOPOGRAPHY 1 JAN 96001 00:00:00 23 71 1 9017 TOPOGRAPHY 1 JAN 96001 00:00:00 25 138 1 9018 TOPOGRAPHY 1 JAN 96001 00:00:00 40 98 1 9019 TOPOGRAPHY 1 JAN 96001 00:00:00 26 100 1 9982 METEOSAT5 19 JAN 96019 16:00:00 26 100 8 9983 METEOSAT5 19 JAN 96019 16:00:00 27 70 8 9995 G-9 IMG 25 JAN 96025 19:00:00 25 138 4 IMGLIST: done The point of this diversion is that you do not want to use these dataset position numbers when running IMGCOPY. Let's assume that you want to copy the latest image in the GE-2B/IR set to MYDATA/IMAGES.2000 while reducing the data to 8-bit but keeping the oversampling: IMGLIST GE-2B/IR FORM=EXP <- to get # LINes and ELEments in image IMGCOPY GE-2B/IR MYDATA/IMAGES.2000 STYPE=VISR SIZE=nlin nele where: nlin - number of lines in GE-2B/IR dataset element nele - number of elements in GE-2B/IR dataset element You can not use SIZE=ALL with STYPE=VISR, this is why you have to interrogate the source image to find out how many lines and elements the source image has and use those numbers to specify the output image "shape". You would repeat this step for each image you want to convert to 1-byte. >then I want to remap them to 2 projections: Remapping is accomplished using the IMGREMAP command. For this, choose a different range in positions numbers in the MYDATA/IMAGES dataset. For sake of argument, let's choose 3000: >North Polar Stereographic projection >#CLAT;CLON;DLAT;DLON >#45.30;-73.35;1.5;4 (CYUL) You will have to play with this to get the RES correct, but the following is the gist: IMGREMAP MYDATA/IMAGES.2000 MYDATA/IMAGES.3000 PRO=PS 45.30 73.35 RES=4 SIZE=ALL >#45.30;-73.35;5;7 (NE US) I'll let you play with the IMGREMAP invocations for this one. >Also, for METEOSAT imagery, I want to remap them to these projections: > >North Polar Stereographic projection >#CLAT;CLON;DLAT;DLON >#46.25;1.50;11.5;16 (France) >#45;14;13;23 (Europe) I'll let you play with the IMGREMAP invocations for these. >Thanks a lot again for the great support...! You are welcome. Tom