Command Line Utilities

• Useful for almost all preprocessing
  • Metadata: gdalinfo
  • Reproject: gdalwarp
  • Format conversion: gdal_translate
  • Stack / mosaic: gdal_merge.py
  • Vector to Raster: gdal_rasterize
• module load gdal/1.10.0
• http://www.gdal.org/gdal_utilities.html

API

Write your own code? Use GDAL API:

• Python
  • module load gdal/1.10.0 (loads python/2.7.5)
  • from osgeo import gdal
• R (via rgdal and raster packages)
  • module load R_earth/3.1.0
  • library(raster)
• C/C++:
  • module load gdal/1.10.0
  • #include "gdal.h"
  • GDAL_LIB and GDAL_INC paths

Command Line Utilities

• ogrinfo
  • Basic information: ogrinfo -so -al vector.shp
  • Simple queries: ogrinfo -al -where "FEATURE > 5" vector.shp
  • SQL for more advanced queries (-sql)
  • Combine with grep, wc, etc... to quickly summarize vector data
• ogr2ogr
  • Format conversion: ogr2ogr -f KML vector.kml vector.shp
  • Reproject: ogr2ogr -t_srs "EPSG:4326" vector_wgs84.shp vector.shp
  • Merge: ogr2ogr -append combined.shp part2.shp
• http://www.gdal.org/ogr_utilities.html

QGIS v2.0

• On par with ArcGIS in some regards, better than in most.
• Built on GDAL/OGR
• QGIS vs ENVI
• Plugin architecture
• module load qgis/2.0.1

Download

Bulk Download Application for L1 products:

• module load bda/1.1.2
• Use qsh session for big downloads -- very CPU intensive!
• Updating is grief inducing... ask IT if update is required

Preprocess

Parallel SR / Fmask for Landsat 4, 5, 7, and 8 in one command:

• module load batch_landsat/v4
• landsatPrepSubmit.sh -h
• Surface reflectance only suggested for Landsat 8 (as of Nov 6th, 2014)
  • LEDAPS for Landsat 4/5/7 from ESPA
  • Landsat 8 version still in development
  • We have ancillary data until 2014 DOY 282
• See tutorial from May 2014

Visualization

Timeseries interactive visualization in QGIS:

• "Stable" - module load CCDCTools/latest
• "Development" - module load CCDCTools/_beta

Git

• Usable version on GEO/SCC
• Cannot push / pull using HTTPS
• Must generate crypto keypair and give Github your public key
• https://help.github.com/categories/ssh/

IPython Notebook

Use Python? Want to share or explain your work, or just save and document your explorations?

• Nature - Interactive notebooks: Sharing the code (doi:10.1038/515151a)
• On GEO:
  • module load python/2.7.5
  • ipython notebook
  • Remember the port it uses!
• Locally:
  • ssh -L [local port]:localhost:[remote port] [user]@geo.bu.edu
  • Visit localhost:[port] in browser
• Secure your notebook session

KnitR

Installed as part of RStudio!