Fast unpacking of QC bit-flags in Python

Satellite remote sensing products often represent quality control (QC) information as bit-flags, a sequence of binary digits that individually (single digit) or collectively (multiple digits) convey additional information about a remote sensing measurement. This information may be related to cloud cover, atmospheric conditions in general, the status of the space-borne …




The Tasseled Cap transformation and band ratios: Applications for urban studies

Urban environments are heterogeneous at relatively small scales and composed of multiple land cover types but are dominated by vegetation, impervious surface, and soil (V-I-S). Land cover indices such as the Biophysical Composition Index (BCI), based on the tasseled cap transformation, attempt to capture the spatial pattern of these three broad classes of urban land cover. Here I present Python examples for applying the tasseled cap transformation and for calculating the BCI.



Clipping rasters in Python

Clipping rasters can be trivial with a desktop GIS like QGIS or with command line tools like GDAL. However, I recently ran into a situation where I needed to clip large rasters in an automated, online Python process. It simply wouldn't do to interrupt the procedure and clip them myself …