Converse.js webchat for prosody-hosted chatrooms

The goal of this post is to make an easily accessible (anonymous) webchat for any chatrooms hosted on a prosody XMPP server, using the web client converse.js. Motivation and prerequisites There are two use cases: Have an easily accessible default support room for users having tro … | Continue reading


@op-co.de | 3 months ago

Samsung NX 2009 Crypto Fail: Social Media Uploads

Back in 2009, Samsung introduced cameras with Wi-Fi that could upload images and videos to your social media account. The cameras talked to an (unencrypted) HTTP endpoint at Samsung's Social Network Services (SNS), probably to quickly adapt to changing upstream APIs without havin … | Continue reading


@op-co.de | 4 months ago

ESP32-EGA16-TGA Shitty Camera

This post is about shooting 16-color EGA (1984) styled retro photos right on the 4$ ESP32-CAM board and storing them to µSD in the arcane TGA (1984) file format. For that, we need to read RGB images, convert them to 16 colors, apply dithering, and store a TGA image file. ESP32-EG … | Continue reading


@op-co.de | 8 months ago

Samsung NX Camera Archaeology

Many years ago, in the summer of 2014, I fell into the rabbit hole of the Samsung NX(300) mirrorless APS-C camera, found out it runs Tizen Linux, analyzed its WiFi connection, got a root shell and looked at adding features. Next year, Samsung "quickly adapted to market demands" a … | Continue reading


@op-co.de | 1 year ago

Energiekrise in Offenbach: Werden alle Ampeln abgeschaltet? - Op Online

... Offenbach ist die Anzahl der in Frage kommenden Gebäude aber überschaubar. Dunkelheit wagen: Nicht nur zur Luminale wie auf diesem © Archiv/P ... | Continue reading


@op-online.de | 1 year ago

OP-Tee: Open-Source Trusted Execution Environment for ARM Platforms

OP-TEE is an open source project which contains a full implementation to make a complete Trusted Execution Environment. The project has roots in a proprietary solution, initially created by ST-Ericsson and then owned and maintained by STMicroelectronics. In 2014, Linaro started w … | Continue reading


@op-tee.org | 2 years ago

Mit einer Schabe fing es an

Der Kran am Hafen hat es Ilona Metscher und Annette Scholz angetan: Immer wieder ist das Baudenkmal auf den Werken des Künstler-Duos zu sehen. Ob im Malbuch für Erwachsene, auf Postkarten oder im neuen Jahreskalender, der sogar komplett dem Kran gewidmet ist. Da wird das Industri … | Continue reading


@op-online.de | 3 years ago

Change Boot Device Order on HP MicroServer Gen8 with Broken NAND

This post describes how to start "Intelligent Provisioning" or the "HP Smart Storage Administrator (ACU / SSA)" on a Gen8 server with a broken NAND, so that you can change the boot disk order. It has been successfully tested on the HPE MicroServer Gen8 as well as on a ProLiant ML … | Continue reading


@op-co.de | 3 years ago

A Simple, Open-Source Ventilator Using a Proportional Solenoid Valve

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@op-vent.stanford.edu | 3 years ago

Luminale 2020: Das sind die Leucht-Stationen in Offenbach

Die Luminale begeistert jedes Jahr Tausende. In Offenbach sind 2020 insgesamt 21 Lichtprojekte zu sehen. Wir sagen, wo sich ein Besuch lohnt.  | Continue reading


@op-online.de | 4 years ago