Optimizing the spectral display in tobes-ui led to a 10-50x speedup in rendering and improved color vibrancy through advanced normalization and precomputation techniques.
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Michal Jirků runs Wejn.org, sharing insights on Linux, programming, and system administration from Zürich, Switzerland.
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This blog post is the eighth in a series about reversing the Philips Hue light driver. It discusses the color rendering index (CRI) of the Philips Hue White Ambiance light, which is criticized for its poor CRI ratings (82-85) acro...
A step-by-step guide to solving the Swisscom 2025 security.txt challenge, detailing file conversion, patching, and flag retrieval methods.
Overengineering float serialization in spectrometer calibration is unnecessary, as simpler methods can achieve adequate precision without complexity.
The author discusses their experience with the Torch Bearer Y21 spectrometer and a cheaper Hopoocolor HPCS-320D, highlighting the challenges of calibrating high-end spectrometers that are not pre-calibrated in absolute radiometric...
The blog post recounts the author's experience participating in the 2024 Swisscom security.txt Challenge, detailing the process of working with a .woz file from an Apple II disk image. The author describes the challenges faced, in...
The author discusses their journey in enhancing the user interface of a spectrometer they acquired after being inspired by a Hackaday article. Initially dissatisfied with the basic functionality of the original UI, they sought gui...
The blog post discusses the author's experience with optimizing a Python class for computing the sliding maximum of incoming values over a defined time window. The author shares their initial struggles with using language models (...
An interactive tool that visualizes the visible spectrum by converting light wavelengths into RGB values, allowing users to adjust color intensities.
The blog post discusses a hands-on project where the author designed a 3D-printed clasp for a sports bag used by Swiss kids in primary school. The author identifies a design flaw in the bag that causes it to slide off children's s...
The post discusses the use of ESP32 as a Zigbee console, focusing on the esp32-c6. It covers the installation process, issues with the console, and solutions to those issues. The author also provides usage examples and shares thou...
The post discusses the process of designing and assembling a PCB, cables, and antenna holder for a zigbee light. It covers the PCB design, component selection, assembly, and the challenges faced during the process.
The post introduces e32wamb, a firmware for esp32-c6 based White Ambiance light. It discusses the problem statement, solution, and dependencies encountered during the implementation. The post also covers the architecture and hurdl...
The text discusses the non-blocking fading of ESP32's LEDC. The author tests the behavior of the LEDC controller when dimming and concludes that the function call will block despite LEDC_FADE_NO_WAIT. The author created a simple t...
The post explains how to get the project (app) versioning automatically using timestamp and git-hash in ESP32 firmware builds. It provides a solution to consistently regenerate the version and includes a version.cmake file to gath...
0Zigbee: Hue-llo world!
2025-01-05 • esp32 wireless communication zigbee philips hue
The text discusses the challenges faced by the author in trying to get a 'Hello, world!'-like sketch from Zigbee world up and running. The author shares the journey, including the problem statement, the plan, and the roadblocks en...
The post discusses the process of reversing the PWM functions for Philips Hue light driver. The author describes the problem statement, the journey of finding a mathematical description of the generating function, and the process ...
The text is about the process of dumping the PWM data for the Philips Hue White Ambiance LED strip. It discusses the problem statement, approach, and different solutions to read the PWM values. It also includes the results and vis...
The post is the first in the Reversing Philips Hue light driver series, focusing on the Philips Hue Engine v1.0 PCB board. The author discusses the quick search, pinouts, and test points on the board, as well as the debug port and...
The author introduces a project to reverse engineer the Philips Hue ceiling lights in order to create a drop-in replacement PCB. The motivation for this project is to prevent neighbors from taking control of the lights through the...
The text provides a guide on how to root the newer Hue Bridge 2 with firmware version 1967054020. It includes detailed instructions on the hardware portion of the mod, accessing uboot, tweaking bootdelay, backing up env variables,...
The article discusses a more elaborate ZFS setup to provide additional peace of mind, including quick notifications of failures, keeping ZFS clean, and reliable auto-snapshotting.
The author discusses the problem of using ssmtp to push email from Linux boxes and the need for a better solution. The author then provides a solution using postfix to send email via authenticated TLS and local queue. The post inc...