OSM printed: Open Street Map on paper in Chiang Mai

Saturday, April 16th, 2016

For the first time, a printed version of Open Street Maps is now available in Chiang Mai. The map is a cycling map, it highlights roads that are especially suitable for cycling and proposes small routes (based on the class:bicycle key).

The map is printed on A2 (420x594mm) and, with a scale of 1:25,000, covers a good area of around 9 x 13 km around Chiang Mai City.

OSM Chiang Mai


Topographic correction of Landsat imagery using GRASS GIS

Wednesday, April 22nd, 2015

The GRASS module i.topo.corr to correct topographic effects on imagery works quite impressively on the Landsat imagery using the recently released Enhanced Shuttle Land Elevation Data with a 1 arc / 30 meter spatial resolution. Here is a quick example to show the difference of the original image and the corrected image that was processed using i.topo.corr and the enhanced SRTM elevation model in GRASS GIS:

Landsat 8 scene (Band 5), uncorrected