Digital Geography

Description code for article “Using the Google Earth Engine (GEE) for Detection of Burned Areas”

I want to continue my article “Using the Google Earth Engine (GEE) for Detection of Burned Areas” (link) and describe in detail script for detection burned areas. I decided to post here code of this script with comments, shchems and illustrations of wotk this scrip Link to script on Google Earth Engine This script shows two variants for detection burned area: Calculating spectral index NBR for before and after forest fire images, download on your computer and compare these scenes in software using function change detection. Calculating spectral index NBR for after forest fire images and select burned areas using threshold. My…

Off Topic: self hosted GIT-server with Bonobo

This might be a bit off-topic for some of you but it was on my desk recently. Furthermore I think this might be interesting for GEO/GIS folks as well: host your own GIT. With GIT your efforts on working together on documents or solutions might be a bit easier. Normally we use GitHub: GitHub is a web-based Git or version control repository and Internet hosting service If you don’t know what GIT/GitHub is about: But what if you have just limited access to the outer world in terms of policies, compliance or just a “bad feeling” in storing/sharing your data,…

Working with Clusters in Leaflet: Increasing Useability

In one of our latest projects we faced a sad truth: geocoding results often sucks and points are not scattered enough but concentrate on distinct locations and clusters will be full of markers. This will lead to heavy clustering if you work with such data in leaflet using the markercluster plugin. In the end it was always hard to find the right point of your interest if you’re facing 20 spiderfied points on one location. So we asked ourself: how can we increase the useability of clusters as we can’t change the location data itself? We came up with a…

Using the Google Earth Engine (GEE) for Detection of Burned Areas

Google Earth Engine ( GEE ) is a cloud platform for processing satellite imageries. This service includes images of Landsat 5, 7,8, Sentinel 1 and Sentinel 2. You can process them directly on Google servers and don’t need download the images. This opportunity does processing of satellite imageries faster then on a limited desktop PC. However, you should have programming skills, because this is based on JavaScript code and the Google Earth Engine API.

planlauf/TERRAIN – a lightweight 3D DEM viewer for daily usage

The visualization and interpolation of 3D terrain (point) data (DEM or DOM) could be a hard task for current GIS software and small to midsize hardware. One thing is the huge possible amount of points and their precision when it comes to airborne or terrestrial LIDAR data with point density < 5m and big areas of interest. Another thing is the rendering performance once the user started his exploration of such a huge dataset. There are several open source and proprietary software solutions and specialized software for several industries. In the following I’ll introduce you to planlauf/TERRAIN, a lightweight DEM…

ALOS World 3D V1.1 vs. SRTM1

Some days ago a new version of the ALOS 30m DEM was released: Void pixels due to clouds and snow pixels within 60 deg. of north and south latitudes in Version 1 were complemented by existing DEMs. Out of the areas are same with Version 1 product. As we already compared ALOS with SRTM-1(I saw the ALOS DEM as “the winner”) I am now interested in how this performs in a another setting. We are changing our focus from Mongolia to Germany and check how the new ALOS DEM works compared with SRTM 1.

Short Announcement: QGIS 3.0 is on its way

QGIS 3.0 is the next big release in terms of features and tools. As it is stated in this e-mail chain we could expect this new major release in late 2017 and time is passing fast: retire 2.14 in June 2017 2.18 becomes LTR from June 2017 to 2018 3.0 feature freeze in July 2017 release 3.0 in Sept 2017 release 3.2 as next LTR in release 3.0 + 4 Months (eta June 2018) Yet this timeline is not strict and [was?] under discussion. We might expect a new candidate loaded with some cool and uncool features.

Map your family tree with Gramps and QGIS – how to digitize and visualize genealogy data

As I realized that I have a really huge family I was keen to digitize the current family tree and get into contact to my relatives. For getting things done, I choose the open source genealogy software Gramps to record all offline information about my family members and create a database as base for further investigations, updates and of course spatial visualization. After that, I exported a database view and visualized it with QGIS.

JuxtaposeJS and the Death (and Re-Birth) of Bogoslof Island

This post is just a quick update on a unique event unfolding in my home state of Alaska and a cool new tool to help you post image sliders on the web.  First, let’s start with the event. The Eruption of Bogoslof Island Over the past few weeks, a volcano has been erupting in Alaska.  This by itself is not that unique, as we have lots of volcanoes and they tend to erupt pretty frequently.  You can check out the current activity for yourself at the Alaska Volcano Observatory.  This most recent eruption is a bit different though.  The island is…

The Atom Code Editor

There is this time of the year when the presents are unboxed and the new year hasn’t started yet, when a lot of people (including me) find some time for tinkering on personal projects. And I guess I am not the only one around here who is working on software projects. But because a proper code editor can make a huge difference,  I want to introduce you to my favorite tool for the job: Atom, a free, open source, modern and extensible, cross platform editor.

Geospatial cloud solutions: Software-as-a-Service vs Roll-your-own

Over the last couple of years, we have seen an increase in demand and offerings of geospatial solutions in the cloud for tasks like web map creation, centralized data storage and management, data vizualization and so on. There is a lot of Software-as-a-service (SaaS) options to explore, but in this article I want to briefly discuss if SaaS is the right thing for you, or wether you should look into rolling your own.