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STRM Data - Importing Process

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Hi,What method dod you use to import the dem data?It should only take a few minutes to import just dems.You have to create / modify an import .txt file for the editor to tell it where to apply your dem data.If you didn't do this then heaven knows where it is applying them.It would take a while to import 915 data files but certainly just a few hours, if that.The process is very straightforward and doesn't take long.Colin

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ColinI've just arrived at home and Fly is still running the importation now importing tile 114/133 almost 24 hours. Fortunately I have backed up some POD and can go back if something is wrong.I've downloaded .hgt files and renamed it as .ras. Then opened Fly editor and used Scenery Import - Generate elevations. Opened the .ras file dowloaded and indicated the lat and lon for upper and lower corners.What I'm doing wrong. Please help me.Thanks for replyingRegardsJJLobo

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ColinI found my error. I was inverting Upper with Lower corners. Doing it right it takes only two to three minutes. Thanks.Regards___ JJLobo ___55 11 37268158

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Hi,I would suggest 2 things.1) If you are just importing dems.To make sure that you get the import file correct, generate the project area in TS2. There's no need to d/l anything, just create the project and save it. Now you can edit the TS2 produced .txt file.Replace the image name with c:dummy.tga and the coordinates with 'none'.Replace the dem name with your dem (ras) file and adjust the LL and UR coordinates to suit your area. Also put in the dem size, 1201 x 1201.2) if you are generating a TS2 image as well then include the dem in your manually-added data folder as per Harald's instructions in another post. This will obviously take the editor considerably more time to process.The only time I saw the editor creating a lot of unwanted trn files was when I had an error in the .txt file. I killed the process with task manager and started over after editing the .txt file.It really should only take some minutes per globe tile. That's of course with no podding.Personally, I like to see what I have created before podding. It's not essential, but just something I always do.Colin

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Like you I have had problems with this.Could you give me a rundown of your procedures on a 1,2,3, basis.I would like to use your example as a test case.Many thanks Richard.

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RichardI've followed Harald's procedures and got success. If you follow it you will also get there. What mistakes complicated my first two tentative:1. I didn't enter Lower/Upper corners information correctly. In south hemisphere LOWER has the Highest Lat and Lon and UPPER has the Lower Lat and Lon.2. I didn

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Hi,I'd just like to contribute my $0.02 worth here:Steps 1 ~ 3 rather depend on what you have installed and the quality of the dem (hgt) file.If you just rename the .hgt file to .raw then Photoshop will open it as it is. I don't know about Paintshop pro but I imagine that it will too. (Just remember that the file is in Motorola format)I would recommend getting a viewer that can display the srtm data.There are lots out there and all free.Personally, I like Global Mapper from http://www.globalmapper.comThis is an excellent program and it is free as a viewer. Only registered versions can export.There is also 3Dem, another free utility and easy to find.There may not be any 'holes' to fill in. The dataset may be complete.Here is a utility to intelligently fill in the holes:http://www.3dnature.com/srtmfill.htmlNow, just rename the .hgt file to .ras and follow steps 4+ and it should work OK :-)The .hgt files are simply a raster of the elevation data in big-endian format, exactly what the editor requires. No other transformation is required other than filling the holes, if any.Hope this helpsColin

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Thanks guys for that really comprehensive help.I'll defininetly have another crack at it.Richard.

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Hi everybody!Back from Christmas-Vacation.I am happy to hear that more People are making scenery with SRTM-Data. Good elevation data (beside of roads, rivers, ...) are really something thats missing in FlyII, at least for Europe and it makes me sorry to see all the SRTM-Meshes for other simulators.Colins2: Thank you for your hint with SRTMFILL. It works wonderful and saves a lot of time. I still use the Paintprogram for flattening lakes and airports.Do you know a program for merging SRTM-Files into one big file? CA Global MApper do this ?I use 3DEM, but found no way to export a .hgt file. So I export it as a "signed integer" .bin file and convert it with a little script to a .hgt-file. (The .bin-file is exactly like the .hgt-file. only little endian instead og big endian).Harald

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Could you enlighten me on the "H3 phyton program" by Harold Kraft. Is this something to download?Richard.

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Rich,I don't know if Harald has uploaded his program.It's a small python script to byte swap from big to little endian and vice versa.I don't have paintshop so I don't know if it is necessary.Colin

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Harald,Global Mapper can merge the dems no problem but only the registered version.There are other options that are free.You could try MicroDEM, I'm sure the latest version handles SRTM data.Colin

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Success. I downloaded and imported S24W047 after using 3D nature to fill the holes. What a dramatic result! One question. How do I go about podding the data files?

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Hi Rich,That's good news :-)Podding is the same as podding scenery.When you import an image say from TS2 or a satellite image, the editor slices the scenery image up into ground tile size bits. It puts these into a folder ..dataDXXXZZZ.It also builds the .trn files, 4 files for each globe tile and puts them in there too.The .trn files contain a list of the little images in the appropriate order and the elevations for these tiles.If you do not import scenery, i.e. just the dem info, then the editor will still create the .trn files but will put values for the default scenery in place of the image names.The evevations will be written from your imported info.The opposite is also true, importing a scenery image without dem info results in the elevations from the default mesh being written in the .trn files.To pod the tiles just check the box on the editor screen.There is one thing to watch for with dems.Say you were applying dems to tile 000:172 (my home tile).The editor will also create trn files for surrounding tiles, like this:255:173 000:173 001:173255:172 000:172 001:172255:171 000:171 001:171These extra .trn files are there to ensure that you get seamless edges on your main tile. If you pod the data and do not include these files then you will get 'jaggies' around the edges once you have deleted the original..datadxxxzzz folders.Colin

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Hi ColinThank you.SRTMfill works wonderfull. I will try Microdem later.By now I will stay with my script. I successfull merged 12 tiles (3 x 4) into one and have now an area from 46N 14E to 49N 18E, which covers the east of austria. I have to rework some airports, than I will upload this data.happy new yearHarald

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Many thanks. I have checked the "make pod" but I havn't been sure of the processes it asks for and cancelled out.ie name file,volume etc.I assume when editing strm files for America that I should use 3601 for the length and height. Are there any other changes from those used with 1201 strm that I should make to the scenery import window.Richard.

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Rich,The filename is whatever you choose.The volume name is largely irrelevant - you can put what you like there. Normally 'created by Rich Press' or something similar. As for the US dems, yes just change the data size, the area will be the same. You will almost always need 4 srtm files to cover 1 globe tile. You might get away with 2 in some places depending on the latitude.There's a free program called MicroDem that will merge the data sets for you into one big file, then you will have 7201 x 7201.Note: NOT 7202 x 7202 because the adjoining values are the same coordinates and same value.Colin

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