Posts on Konrad Heidler

Japan Shader

Mon, 26 May 2025 00:00:00 +0000

Mountains fading out toward the horizon. This is what we’re looking to re-create in a shader. Photo taken from Oyunohara View Point, Wakayama Prefecture

Final Applet

PixelDINO: Semi-Supervised Semantic Segmentation for Detecting Permafrost Disturbances

Mon, 03 Jun 2024 00:00:00 +0000

In sync with the changing climate, permafrost is undergoing rapid transformations. As temperatures rise, the frozen ground starts to thaw, which has various consequences. Not only does permafrost thawing pose risks to local infrastructure such as roads and buildings, but it also tightly connected to the global climate system by potentially releasing stored carbon into the atmosphere.

Distribution of permafrost in the northern hemisphere. (Visualisation based on data from NSICD)

COBRA: A Deep Active Contour Model for Delineating Glacier Calving Fronts

Mon, 31 Jul 2023 00:00:00 +0000

Existing approaches for calving front detection generally work by first performing a pixel-wise segmentation or edge detection, and then extract the actual calving front in a post-processing step. Our goal in this study is to build a model that only needs a single step, and directly outputs the calving front as a polyline.

Following the idea of explicit contour prediction, we have developed a new method called “Charting Outlines by Recurrent Adaptation” (COBRA). It works by combining the idea of Active Contour models with deep learning. First, a 2D CNN backbone derives feature maps from the input imagery. Then, a 1D CNN (Snake Head) iteratively deforms an initial contour until to match the true contour.

Seeing the Bigger Picture: Enabling Large Context Windows in Neural Networks by Combining Multiple Zoom Levels

Tue, 12 Oct 2021 00:00:00 +0000

Read the full paper on IEEE Xplore.

Self-supervised Audiovisual Representation Learning for Remote Sensing Data

Mon, 02 Aug 2021 00:00:00 +0000

Read the full paper at Science Direct.

HED-UNet: Combined segmentation and edge detection for monitoring the Antarctic coastline

Tue, 23 Mar 2021 00:00:00 +0000

Read the full paper on IEEE Xplore.

Remote Sensing for Assessing Drought Insurance Claims in Central Europe

Thu, 14 Nov 2019 00:00:00 +0000

Read the full paper on IEEE Xplore.

Soap Bubbles

Thu, 06 Jun 2019 09:00:00 +0100

Have you ever wondered about the rainbows on CDs, gasoline puddles or soap bubbles? All of these have the same cause: The interference of light on thin surfaces. Today, we’ll try to render something that looks like a soap bubble.

Some Physics

When a ray of light hits the surface of the soap bubble, it is either instantly reflected, or it enters the soap film and is refracted. When it is refracted, it can then be reflected off the other end of the soap, and then leave it again at a slightly different spot. There are countless other possiblities for the ray to bounce around, but these are the two that we will focus on here.

Reversing Hill Shading in Digital Elevation Models

Thu, 03 Jan 2019 09:00:00 +0100

A while back on the Geographic Information Systems Subreddit I stumbled upon this question. A user wished to get height information from this elevation map they had found somewhere:

Unforunately it has hill-shading applied on top of the color bar. While this shading technique makes it easier to understand the terrain structure at a glance, it also makes it harder to extract the raw height data from the map. So first we’ll have to understand how hill-shading works in order to find a way to get around it.

Pachelballs

Tue, 25 Dec 2018 09:00:00 +0100

When I was a kid, I really enjoyed this game called Electroplankton. Especially the game mode called Hanenbow, where you launched small tadpoles onto leaves. On impact the leaves would emit glockenspiel sounds, and create a nice sounding melody. Here’s what it looked like:

I wondered, how hard could it be to implement something similar? If you just want to see the animation, click here. If you’re interested in the background, read on!