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>From: address@hidden >Organization: GMU >Keywords: 200501201830.j0KIUJv2013893 McIDAS AREA GeoTIFF ADDE Ying, >I am planning to georeference the GOES data downloaded via LDM. Since >the navigation block in area file is complex, it seems the easiest way >is to use McIDAS. Until now, I installed McIDAS and is able to display >the most recent GOES12 image in the image window. OK. >The questions are: > >1) How to make McIDAS output the image into GEOTIFF format, I can not >find such option from the "save as..." menu You will need to do this from the McIDAS command line. The steps are basically: 1) create an output ADDE dataset of type GEOT. Here is the example mentioned in the online HELP for DSSERVE: DSSERVE ADD GEOTIFF/GOES GEOT 1 9999 TYPE=IMAGE "GeoTIFF GOES image files 2) use IMGREMAP to remap the desired source image into a destination GeoTIFF image that has a RECTilinear projection. Here is the information included in the online help for DSSERVE: ************************ GeoTIFF Dataset Remarks *********************** GeoTIFF images are similar to TIFF images, but include calibration and navigation information. They are used by the GIS community and can be viewed with ARCVIEW or other GIS software packages. You can create GeoTIFF image files from other TYPE=IMAGE datasets. To do so, make a GeoTIFF image dataset with a DSSERVE command similar to: DSSERVE ADD GEOTIFF/GOES GEOT 1 9999 TYPE=IMAGE "GeoTIFF GOES image files. Then specify GEOTIFF/GOES as the destination dataset with a positive position number in an IMGCOPY, IMGFILT, IMGOPER or IMGREMAP command. If you use IMGCOPY, IMGFILT or IMGOPER, the source image must be in a rectilinear projection. If you use IMGREMAP, the source image can be in any projection, but you must specify PRO=RECT to make the destination GeoTIFF image a rectilinear projection. IMGFILT, IMGOPER, and IMGREMAP save the image with BRIT calibration. IMGCOPY can save it with other calibrations by using the UNIT keyword. The output file name consists of "TIFF" followed by the position number and extension ".tif". For example, the command IMGCOPY GOESEAST/VIS GEOTIFF/GOES.300 SIZE=ALL creates an output file named TIFF0300.tif that's mapped to position 300 of the dataset GEOTIFF/GOES. 3) assuming that you setup ADDE datasets for the GOES imagery you are ingesting using the IDD, you should have a dataset with group name RTIMAGES. To verify this, run the following: <as 'mcidas'> cd ~mcidas/workdata dsinfo.k IMAGE RTIMAGES If you get a listing of types of images in the dataset RTIMAGES, you will be set to go. If you do not, it most likely means that you have not setup the RTIMAGES dataset on your machine. Please let me know if that is the case, and I can walk you through the setup process. 4) Create an output GeoTIFF image from some portion of an input GOES image. Here is a simple example that creates a GeoTIFF image centered over Miami, Florida (station ID is KMIA) from the most recent GOES-East Visible image remapped into a RECTilinear projection whit resulting resolution of 4 km (the same as the input image) of size 800x800: imgremap.k RTIMAGES/GE-VIS GEOTIFF/GOES.1 STA=KMIA PRO=RECT RES=4 SIZE=800 800 You should play with the center point, output size, output resolution, output image type (e.g., VIS vs IR, etc.), and so on to get a feel for how this works. >2) Since what I want is the real-time georeferenced image, is it >possible to let McIDAS automatically output the area file to such >format, like GEOTIFF, as soon as the area file is avaiable on local >machine? Yes. You can create an LDM pqact.conf action that will run a McIDAS script that will do the remapping into RECTilinear projection in an output ADDE GEOT dataset so that when a new image comes in, an output GeoTIFF image will be created. >Thanks a lot for your help!! No worries. Cheers, Tom -- NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.