5 Free Global DEM Data Sources – Digital Elevation Models
Want to elevate your chances of finding a digital elevation model? Sure you do. You should dive into our list of free global DEM data sources.
Want to elevate your chances of finding a digital elevation model? Sure you do. You should dive into our list of free global DEM data sources.
If you’re searching for free satellite imagery, we rank the best sources of free satellite data from authoritative sources like NASA, USGS and Maxar.
If you want to download Sentinel satellite data, then you’ve come to the right place. We show you how to obtain free Sentinel satellite data.
From geodatabases to PostGIS, spatial databases have quickly become the primary method of managing spatial data effectively in a GIS.
Over the years, the USGS has been a driving force in the production of GIS data. The USGS formats we explore are DLG, DRG and DOQ.
Bit depth is the amount of detail in each pixel expressed in units of bits. 1-bit rasters contain 2 values while 8-bit rasters range from 0-255
Deploying efficient raster GIS compression techniques means reducing storage space. It can save money, time and also help network performance.
The main spatial data types are vectors and rasters. Rasters have grid cells while vectors are points , lines and polygons consisting of vertices & paths.
TIGER GIS data has transformed the GIS environment because it was the first nationwide digital map. It stimulated projects like MapQuest, Yahoo & Google.
Unsigned integer rasters are non-negative numbers. Signed integers can store negative values. IMG, TIFF & GRID formats are acceptable for signed integer