nsw_lidar
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nsw_lidar [2019/02/10 13:59] – bushwalking | nsw_lidar [2019/02/11 08:28] – bushwalking | ||
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For more options in compression, | For more options in compression, | ||
* GRASS : [[https:// | * GRASS : [[https:// | ||
+ | V.generalize can also be used to smooth contours - possibly best done prior to simplificiation | ||
==== Cleaning ==== | ==== Cleaning ==== | ||
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{{: | {{: | ||
- | The raster channel network can then be classified | + | ==== Classification ==== |
+ | |||
+ | For 1:25000 maps, I've had reasonable results from using the following formula in the Raster Calculator to classify the streams into categories. Different scales may need different bounds, | ||
+ | |||
+ | '' | ||
+ | |||
+ | * Intermittent: | ||
+ | * Minor: 6.15-7.4 | ||
+ | * Major: 7.4+ | ||
+ | |||
+ | ==== Convert to Vector and Simplify ==== | ||
+ | |||
+ | Convert | ||
+ | |||
+ | {{: | ||
+ | |||
+ | The raw stream data is very jagged. Smooth using | ||
+ | * v.generalize | ||
+ | * Algorithm = Hermite (there are other options which can be used) | ||
+ | * Maximal tolerance value = 20 (in m, obviously scale dependent) | ||
+ | |||
+ | Simplify using using: | ||
+ | * Vector geometry : Simplify | ||
+ | Tolerance:? | ||
===== Clifflines ===== | ===== Clifflines ===== |
nsw_lidar.txt · Last modified: 2023/06/02 12:33 by allchin09