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Ahmed FASIH @22

Any digital elevation map fans in the house? The Kyoto area according to ASTER v2 and the SRTM v3, both ~1 arcsecond (30 meters per pixel). In the former you can much more clearly see the Kamo River, flowing alongside 下鴨神社 and 上賀茂神社 near the top.

Texture shading forthcoming.

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Should probably publicly tag these with 😅!

Notice how, in the texture-shaded versions, the spiny ridges of mountains and the river valleys pop out. Texture-shading is just a specific sharpening filter invented by Leland Brown and implementable in ~2 lines of Julia/Python/Matlab. (To make it work on global datasets, i.e., terabyte-sized maps, though, you need a few more lines—basically Hankel transforms, overlap-add convolution, and memory-mapped files.)

The conventional way to show terrain is hill-shading, per this Google Terrain map. For many use-cases, like preparing to walk a terrain, or understand its drainage systems, or trace the ridges of its hills, texture-shading is way better 😌. (10 meters per pixel USGS NED data, , , USA).

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