A collection of raster tools.
For development, you can use a docker-compose setup:
$ docker compose build --build-arg uid=`id -u` --build-arg gid=`id -g` $ docker compose up --no-start $ docker compose start $ docker compose exec lib bash
Note that the /mnt folder is already mapped to the host mount.
Use fillnodata to fill nodata regions in rasters. The input to the algorithm is the edge surrounding the region. The raster saved as the target argument only contains the complementary cells.
For rasterization of landuse tables from a postgres datasource a special wrapper command is available at bin/rasterize-landuse, use --help for args.
Run the following scripts for streamline calculation:
flow-fil # depression filling flow-dir # direction calculation flow-acc # accumulation flow-vec # make shapefiles flow-rst # make rasters from shapefiles
Streamlines have been rasterized in the past to be able to visualize them with good performance on any zoomlevel. A number of tricks can be to make them look like a vector dataset:
- Rasterize at sufficiently high resolution so that supersampling is never needed
- (Pre)aggregate using a maximum algorithm for lower resolutions
- Use binary dilation after serving image tiles on one or more higher classes to create a 'wider stroke' effect
A number of scripts have a --part option to run the script on a subset of the
source features, e.g. --part=2/3 to run on the second part of three parts. To
use xargs to run some script for example on 4 processes, use:
xargs -a <(echo -e '1/4\n2/4\n3/4\n4/4') -L 1 -P 4 your_script --your_args --part
