A journey of creating a vessel tracking web map from a series of static vessel map images.
Cloud Optimized GeoTIFF (COG) are geotiff files, like satellite imagery, that have been processed in a manner that makes it easy to consume for internet processing applications (read cloud). It is the brainchild of some very smart people at very smart organizations (Amazon, Planet, MapBox, ESRI, USGS and the landsat-pds mailing list) and is supported by major processing software such as ESRI, Rasterio, Geoserver, QGIS and GDAL.
Google Maps have been with us since February 2005, virtually a decade ago as I write this (expect a party on Feb 8th 2015). From their acquisitions of Where 2 Technologies and Keyhole, Google ignited a cartographic web revolution. Yes, of course there were maps on the internet pre-Google Maps, but Google brought the web […]
What’s all the racket? These little artifacts along the edge of the data look like they should be considered nodata however they show up despite setting the nodata to be transparent. Turns out these cells are slightly off-white and were likely introduced during JPEG compression. This can happen with both 0 (black) and 255 (white) nodata values.
It is not uncommon for raster data to be large and unruly. Creating tiles is one way to deal with these large datasets and speed up rendering. This post introduces a few handy tools for dealing with raster data while walking through the process of combining multiple raster files to create tiles for a super-overlay […]
OGR2OGR is a hugely useful GIS utility. Today I was using it to copy data between an Amazon Web Services (AWS) based PostGIS database and a local PostGIS database. This is a slightly weird use case, but I wanted to pull down some data locally for editing via Quantum GIS (QGIS). Here’s the command I used: […]