A-Frame Windows Mixed Reality standalone app

September 26, 2020

Building a standalone (aka kiosk) virtual reality (VR) application on the Windows Mixed Reality (WMR) platform has some challenges, even more, if it is a WebXR app, based on the A-Frame framework. Two challenges which need to be solved: Starting up the VR application on every startup of the Windows 10 system. That is, opening the app inside the WMR platform. The WMR platform goes into a standby mode after some time if the headset is not used. ... Read more

Tensor operations and primitives (with Tensorflow)

August 3, 2020

For fluently reading and writing custom TensorFlow code (e.g., custom loss functions, custom layers, …) a good understanding of basic tensor operations is necessary. This article gives an overview of operations, which are commonly found in the wild. Terminology A tensor is a multi-dimensional data structure (basically another name for a multi-dimensional array). Tensors (tf.Tensor) have a fixed shape, which defines the number of dimensions (aka axis) and the number of items within each dimension. ... Read more

Preparing Windows for Tensorflow GPU training

March 17, 2020

There are some important requirements and dependencies which have to be exactly followed. In this article it is described how to use Tensorflow 2.1 with the respective CUDA 10.1 version. This setup most likely changes for future versions of Tensorflow. Check the Tensorflow websites for installation and gpu support to get an updated list of requirements. Setup Windows 10 Check CUDA support for your Nvidia GPU Python 3.7 64-bit version pip 19. ... Read more

PHP built-in web server

December 12, 2018

PHP comes with a built-in web server for local development. The web server can be started and stopped via command line and has some basic configuration options. Basic usage After a successful installation of PHP the php command should be available on the terminal. This can be tested with a simple version check: php --version If PHP is installed correctly a version statement should be printed out on the terminal. For starting the built-in web server the S command option can be used. ... Read more

Stylesheet for printing

April 8, 2018

CSS can also be applied for styling paged media. Major browsers support basic primitives for print stylesheets. However, some more advanced features are only supported by proprietary render engines. Loading the print stylesheet A complete stylesheet document or single CSS rules can be contextually loaded based on the media type. There are basically 4 different media type contexts for stylesheets: all: which is default and is used for all contexts. ... Read more

Proof of work

December 20, 2017

In this article proof of work, as used in bitcoin and other cryptocurrencies, is explained. Also a small demonstration, which simulates proof of work inside the browser is linked. Hashcash Originally proof of work algorithms were researched to be an effective measure against spam or denial of service attacks. Adam Back released a paper in 2002 were he named this approach as Hashcash. Similar approaches seem to be older than Hashcash, as found in the related work section on the Hashcash website. ... Read more

Understanding ERC-20 tokens

December 17, 2017

With the ERC-20 token standard an interface for ethereum smart contracts was defined to represent tokens on the ethereum blockchain. A common standard for the representation has many benefits for the future advent of blockchain based applications. Various applications can be built based on the token standard, which will allow to plugin every token complying with the standard and make it workable with the application: ERC-20 compliant wallets: Basically all tokens complying can be managed within one and the same wallet. ... Read more

© 2020, Stefan Huber