2
votes
1answer
385 views

Polygonize.py outputs into a single file or simple merge?

Given an unique raster topographic file at start, I want to get vector polygons for elevations thresholds 1m, 200m, 500m, 1000m, 2000m into a single shp file. I first slice my raster into 5 (or more) ...
0
votes
1answer
85 views

Gdal_polygonize: How to filter pixels above a given value (elevation)?

Given a topographic GIS raster of one country: Given an elevation threshold n = 50 (meters) How to polygonize pixels when z >= n ? gdal_polygonize.py is not clear on this point. It states This ...
2
votes
2answers
297 views

A library/software to create DEM from a topographic map

In one of my projects I need to digitize video clips showing some natural landscape. Specifically I need to know distances between different areas and elevation levels. I have a topographic map of ...
7
votes
3answers
241 views

What does this style of line on Topographic maps indicate

If I was reading the purpose of this stackexchange site right, I could also ask general map questions. Not necessarily regarding software. Anyways, I was wondering if someone could inform me what ...