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Hi Rogério, re: > Besides raw data from TeraScan we have the same data in other formats > like netCDF, geotiff, binary, both calibrated and non calibrated, what I > want to do is create a area file with any of these, OK. When you say 'binary', what exactly do you mean? McIDAS-X has four routines that make the creation of a navigaged and calibrated image in AREA format very easy for data in a binary raster format: MAKEAREA MAKNAV PRDUTIL IMGCHA I use these routines from time to time to convert imagery in some picture format (e.g., GIF, JPG, PNG, etc.) into AREA files so that they can be used in McIDAS and GEMPAK. The problem is that CPTEC is not licensed to use McIDAS-X, so it has no simple way to take advantage of these routines. re: > Now I am studying the concepts and looking the better way to do this, > when I saw the Daren's email I thought it would be easy, but now I > discarded this and looking to convert a calibrated binary file The process is simple in concept: Add AREA header blocks to a raster of image values (this is what MAKEAREA does); add navigation (this is what MAKNAV does; this is a little tricky if the image is in its original satellite projection; it is easy if the image has been remapped into a known rectilinear projection); add calibration to the image if needed (this is what PRDUTIL does; it is not needed if the values are already calibrated so that there is the standard mapping from brightness (1-byte value that ranges from 0 to 255) to temperature (for IR images, that is)); and then update AREA file header values to match the image (e.g., the date, time, sensor source, etc.). Darren followed this approach in his work, and it worked nicely. The only drawback was that for VIS images, the raster that Darren worked with was an albedo representation that had to be interpreted back into raw counts. The other thing was that Terascan (at least the version that Darren was using) would apply some sort of conversion to the pixel values in the raster, and this made the back conversion to raw counts suspect. I compared images that Darren produced from his procedure to images ingested directly from GOES and found that the procedure worked acceptably well for infrared channels, but not so well for visible images. By the way, I must tell you that we avoided the need to convert Terascan TDS imagery to McIDAS AREA format by licensing the SDI package from UW/SSEC; splitting the signal coming from our GOES receivers (we ingest GOES-East, GOES-West, and GOES-South America) so that it feeds a machine setup for SDI while still feeding a Terascan system. The SDI system ingests the satellite data and makes it available via McIDAS ADDE. The end user then then use an ADDE-enabled application (e.g., McIDAS-X, IDV, McIDAS-V) to view/analyze/copy the images to a local file. McIDAS-X can do the copy so that the result is a McIDAS AREA file that we then distribute in the UNIWISC (aka MCIDAS) IDD feed. Waldenio can fill you in on the IDD. re: > I read this doc: > http://www.ssec.wisc.edu/mcidas/doc/misc_doc/area2.html, I'll try to > create a c-file to write area file, until now I apreciate much your support OK. I will be glad to provide comments and help if you run into areas where you need information. I will also be happy to compare images that you produce with ones created from SDI-ingested data. I have done this before and provided the results to Waldenio; this is what pointed out some problems in the method then being used at CPTEC to create AREA files that were distributed in the IDD-Brasil. 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: AME-140292 Department: Support McIDAS Priority: Normal Status: Closed