SRTM .hgt File Handling

Markus Gpsmax shared this question 2 months ago
In Progress

How is Locus Handling the .hgt Files ?

I mean, the SRTM format is same as BIL. Difference: just with defined pixel rows and clumns.

Is Locus able to handle a bigger .hgt file ? Do Locus calculate the pixel-spacing or just use one of the 2 normal possible ?

I want to use a much more detailled height model ! (Lidar Data with 50cm Spacing or 1 m)

Comments (5)

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Good day Markus,

if you have data prepared, best is to give it a try. I think it should work (and if not, create a bug report and attach one file for test). Only thing I'm little worried is fact, that app load necessary HGT files directly into memory for a lot faster work. 1m files will be probably really huge so there will be need for some automatic optimization and disabling this system. Anyway give it a try and you will see, I've personally never tried/used such huge HGT files.

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Ok, Thanks for fast Answering

I use GlobalMapper to export my Data to the .bil Format. (Motorola BigEndian Byte-Order) rename it to .hgt

Delete the corresponding File that Locus downloaded and replace it with my "new" one.

When I export my Data as .hgt -File (SRTM 1") i get it working but with the standard resolution. And it seems also to be very close to .bil format. (I am just able to export as .bil in custom Resolution)

I think i should keep the square Area of the Data so that Locus maybe is able to use it. (I don´t know how Locus parses the Data).

So I give it a try the next Days.

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I'm not sure if simple rename will work, you will see. I remember I worked with bil format some time ago, but it's direct internal support was removed few years ago.

App should anyway work with all HGT files, no matter how precise they are.

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It is working when i export as .bil file with same Resolution than 1 arc second. (so export as .bil and just rename works)

So it seems now that locus is just using one of the standard resolutions for srtm-files and can´t handle other resolutions.


Maybe if we say all files contain Data for 1 square arc second tiles. So we are able to calculate the point-density.

And locus load just a maximum count of opints to working memory (ram) ? to save memory.


My task is to use it in a mountain Rescue Team, and when we go to unknown terrain sometimes it helps to see in high detailled height model where are holes or steep rocks. or get back height values.


OK i can load a Hillshade-Map with high detailled Raster hillshade. but then i don´t have the right height data.

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Good day Markus,

I'm checking implementation of this feature and for me it should work, no matter how big are HGT files.

May you please share one file with me for test? Thank you.