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On 28/02/2020 2:12, ming han wrote:
Using GRASS, the way to do this involves two steps: first you want to "thin" the raster streams using the module
"r.thin". This insures that there will not be adjacent pixels. Then, when you convert to stream lines, specify the type as line feature. So here are the commands (if you have a raster stream network called "streams"):
r.thin streams output=streams_thin r.to.vect streams_thin output=streams_vector type=line
In addition, I should mention that GRASS offers a set of plugins for hydrology: r.stream.*. Among them is the module r.stream.order. Using this plugin you can create a stream vector directly from the flow direction and flow accumulation grids, and you get the stream order and upstream flow accumulation area "for free".
HTH
-- Micha Silver Ben Gurion Univ. Sde Boker, Remote Sensing Lab cell: +972-523-665918 https://orcid.org/0000-0002-1128-1325 |
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