How do I smooth a terraced toppographical map?

[PTTG]

I have a simple map of a region I'd like to work into a heightmap. I have rough elevation lines and the areas in-between filled with flat shades; effectively, it's a very harsh terracing of an ordinary height map.

What's a simple, effective way to convert that into a full, sloped height map? I could use blur, but I want to maintain detail wherever possible.

[johnvanvliet]

i am betting this is what happened

you had a 16 bit ( 0 to 65535 ) dem
and converted it to a 8 bit ( 0 to 255 ) image


there are a few ways to SYNTHETICALLY move the 8 bit data into 16 bit

but NONE are good


wilbur uses a blur

the best option really is using a PDE to inpaint the missing data on a massive enlargement and then reduce the size
there is a tool ( terminal based ) called Gmic it uses cimg.h

example "image.pgm" ( a 1024x1024 8 bit rgb )
use non repeating numbers like 3.1415 & 1.41421

gmic image.pgm  -upscale_smart 314.141%,314.141%,100%,2,0.5,1 -resize 1024,1024 -to_colormode 1 -n 0,65535 -type ushort -o image.16bit.tiff

or something like that


you can also use a vector image tool like inkscape to convert it to a SVG

import it into blender as a plain
and bake a height map

that might give the best results but it is not easy for the new to blender user

there is a LOT to learn for that

[waldronate]

wilbur uses a blur

I'm utterly baffled by this statement. Wilbur might be able to apply a blur to a surface, but that's not its only trick, and certainly it's about the worst one to apply here.

If, as the original post suggests, he has painted contour levels for his map, then there are many ways to get nice results. Using Wilbur is one solution that could increase detail, but it won't give the exact contour lines with smooth results between them (although the image that he describes might be amenable to Wilbur's deterrace option). http://www.cartographersguild.com/sh...ad.php?t=29412 has some useful Wilbur tutorials, of which the most applicable would be the CSU Johnsondale one (make one mask per contour level and go from there, or just use the base filled contour as a base for the noise/fill/incise/precipiton loop). Of course, the Wilbur web site is still down, likely making this whole Wilbur discussion irrelevant.

To smoothly interpolate the contours, I'd probably run an edge detector on the input image to isolate the contours and then use a thin-plate spline solver to bend a surface across that point set. I'm not sure that a smooth results is desirable in this case, though.

[johnvanvliet]

waldronate my mistake