Booting Faster (with Linux).

Booting a computer does not happen extremely often in most use-cases, yet it’s a field that has not seen as much optimization and development as others had.

Find a very interesting presentation on the topic: How to make Linux boot faster here. The presentation was held at the Linux Plumbers Conference 2019.

Convert HEIC to JPEG or PNG

If you own a modern age phone it’s very likely that it will store the photos you take in a wonderful format called HEIC – or “High Efficiency Image File Format (HEIF)”.

Now the issue with this format is that your average toolchain is based upon things like Portable Network Graphics (PNG), JPEG and maybe GIF or Scalable Vevtor Graphics (SVG).

So HEIC does not quite fit yet. But you can make it fit with this on Linux.

Imagemagick and current GIMP installations apparently still don’t come pre-compiled with HEIF support. But you can install a tool to easily convert an HEIC image into a JPG file on the command line.

apt install libheif-examples

and then the tool heif-convert is your friend.

QuickCharge 3 (QC3) enable your Arduino project

You might have asked yourself how it is that some phones charge up faster than others. Maybe the same phone charges at different speed when you’re using a different cable or power supply. It even might not charge at all.

There is some very complicated trickery in place to make those cables and power supplies do things in combination with the active devices like phones. Many of this is implemented by standards like “Quick Charge”:

Quick Charge is a technology found in QualcommSoCs, used in devices such as mobile phones, for managing power delivered over USB. It offers more power and thus charges batteries in devices faster than standard USB rates allow. Quick Charge 2 onwards technology is primarily used for wall adaptors, but it is also implemented in car chargers and powerbanks (For both input and output power delivery).

Wikipedia: Quick Charge

So in a nutshell: If you are able to speak the quick charge protocol, and with the right cable and power supply, you are able to get anything between 3.6 and 20V out of such a combination by just telling the power supply to do so.

This is great for maker projects in need of more power. There’s lots of things to consider and be cautious about.

“Speaking” the protocol just got easier though. You can take this open source library and “power up your project”:

The above mentioned usage-code will give you 12V output from the power supply. Of course you can also do…:

Be aware that your project needs to be aware of the (higher) voltage. It’s really not something you should just try. But you knew that.

More on Quick Charge also here.

smart arduino fish pond feeder: TurtleFeeder

We’ve got several quite big fish tanks in our house. Mainly used by freshwater turtles.

say Hi! to Wilma.

These turtles need to be fed every once in a while. And while this is not an issue normally it’s an issue if you leave the house for travel for an extended period of time.

Of course there are humans checking on everything in the house regularly but as much as can be automated should and will be automated in our household. So the requirement wa to have the turtle feeding automated.

To achieve this is would be necessary to have a fixed amount of turtle food be dispensed into the tanks on a plan and with some checks in the background (like water quality and such).

It’s been quite a hassle to come up with a plan how the hardware should look like and work. And ultimately i’ve settled on retrofitting an off-the-shelf fish pond feeder to become controllable through MQTT.

The pond feeder I’ve found and used is this one:

It’s not really worth linking to a specific product detail page as this sort of feeder is available under hundreds of different names. It always looks the same and is priced right around the same.

If you want to build this yourself, you want one that looks like the above. I’ve bought 3 of them and they all seem to come out of the same factory somewhere in China.

Anyway. If you got one you can easily open it up and start modifying it.

Hardware

the wheel is turned by a DC motor and the switch is triggered by the wheels fins
I’ve added a connector to the switch and the motor cables for quick connect

The functional principle of the feeder is rather simple:

  1. turn the feeder wheel
  2. take the micro-switch status in account – when it’s pressed down the wheel must be pushing against it
  3. turn it until the micro-switch is not pressed anymore
  4. turn some more until it’s pressed again

Simple. Since the switch-status is not known on power loss / reboot a calibration run is necessary (even with the factory electronics) every time it boots up.

After opening the feeder I’ve cut the two cables going to the motor as well as the micro-switch cables. I’ve added a 4-Pin JST-XH connector to both ends. So I can reconnect it to original state if desired.

These are all the parts needed:

I am using a Wemos D1 Mini and a couple of additional components apart from the prototype board:

A PN2222 NPN transistor, a rectifier diode 1N4007 and a 220 Ohm resistor.

I’ve connected everything according to this schematic I’ve drawn with Fritzing:

I’ve then prototyped away and put everything on the PCB. Of course with very limited solderig skill:

As you can see the JST-XH connector on Motor+Switch can now be connected easily to the PCB with all the parts.

Make sure you check polarity and that you did correctly hook up the motor and switch.

When done correctly the PCB (I’ve used 40mm x 60mm prototype pcb) and all cables will fit into the case. There’s plenty of room and I’ve put it to the side of it. I’ve also directly connected an USB cable to the USB port of the Wemos D1 Mini. As long as you put at least 1A into it it will all work.

Software

Since the Wemos D1 Mini sports an ESP8266 and is well supported by Arduino it was clear to me to use Arduino IDE for the software portion of this project.

Of course everything, from schematics to the sourcecode is available as open source.

To get everything running you need to modify the .ino file in the src folder like so:

Configuration

What you need to configure:

  • the output pins you have chosen – D1+D2 are pre-configured
  • WiFi SSID + PASS
  • MQTT Server (IP(+Username+PW))
  • MQTT Topic prefix

Commands that can be sent through mqtt to the /feed topic.

MQTT topics and control

There are overall two MQTT topics:

  • $prefix/feeder-$chipid/state
    This topic will hold the current state of the feeder. It will show a number starting from 0 up. When the feeder is ready it will be 0. When it’s currently feeding it will be 1 and up – counting down for every successfull turn done. There is an safety cut-off for the motor. If the motor is longer active than configured in the MaximumMotorRuntime variable it will shut-off by itself and set the state to -1.
  • $prefix/feeder-$chipid/feed
    This topic acts as the command topic to start / control the feeding process. If you want to start the process you would send the number of turns you want to happen. So 1 to 5 seems reasonable. The feeder will show the progress in the /state topic. You can update the amount any time to shorten / lengthen the process. On the very first feed request after initial power-up / reboot the feeder will do a calibration run. This is to make sure that all the wheels are in the right position to work flawlessly.

So if you want to make it start feeding 3 times:

mosquitto_pub -t house/stappenbach/feeder/feeder-00F3B839/feed -m 3

And if you want to see the state of the feeder:

mosquitto_sub -v -t house/stappenbach/feeder/feeder-00F3B839/state

All in all there are 3 of these going to be running in our household and the feeding is going to be controlled either by Alexa voice commands or through Node-Red automation.

An Introduction to D3.js

Browsers can do many things. It’s probably your main window into the vast internet. Lots of things need visualization. And if you want to know how it’s done, maybe do one yourself, then…

D3.js is a JavaScript library for manipulating documents based on data. D3 helps you bring data to life using HTML, SVG, and CSS. D3’s emphasis on web standards gives you the full capabilities of modern browsers without tying yourself to a proprietary framework, combining powerful visualization components and a data-driven approach to DOM manipulation.

D3.js

And to further learn what it’s all about, go to Amelia Wattenbergers blog and take a stroll:

So, you want to create amazing data visualizations on the web and you keep hearing about D3.js. But what is D3.js, and how can you learn it? Let’s start with the question: What is D3?

While it might seem like D3.js is an all-encompassing framework, it’s really just a collection of small modules. Here are all of the modules: each is visualized as a circle – larger circles are modules with larger file sizes.

An Introduction to D3.js

BlaspBerry v2

Have you ever wanted a full control over your communication tool ? #SnapOnAir #BlaspBerry v2. A true Qwerty computer KB. @Raspberry_Pi
zero W. @Quectel
3G cellular chip. #Lora RFM95 chip. All opensource.

pwav robot on Twitter

There’s a full twitter thread here. More pictures, more information.

And there’s a GitHub repository with some schematics, configurations and so on…

nodes – a new way to create with code

In Nodes you write programs by connecting “blocks” of code. Each node – as we refer to them – is a self contained piece of functionality like loading a file, rendering a 3D geometry or tracking the position of the mouse. The source code can be as big or as tiny as you like. We’ve seen some of ours ranging from 5 lines of code to the thousands. Conceptual/functional separation is usually more important.

Nodes.io

Nodes* is a JavaScript-based 2D canvas for computational thinking. It’s powered by the npm ecosystem and lives on the web. We take inspiration from popular node-based tools but strive to bring the visual interface and textual code closer together while also encouraging patterns that aid the programmer in the prototype and exploratory stage of their process.
*(not to be confused with node.js)

cross-platform NES emulator written in C#

XamariNES is a cross-platform Nintendo Emulator using .Net Standard written in C#. This project started initially as a nighits/weekend project of mine to better understand the MOS 6502 processor in the original Nintendo Entertainment System. The CPU itself didn’t take long working on it a couple hours here and there. I decided once the CPU was completed, how hard could it be just to take it to next step and do the PPU? Here we are a year later and I finally think I have the PPU in a semi-working state.

XamaiNES

If you ever wanted to start looking at and understand emulation this might be a starting point for you. With the high-level C# being used to describe and implement actual existing hardware – like the NES CPU:

Implementation of the Logical Shift Right opcode of the MOS6502 cpu

The author does the full circle and everything you’d expect from a simple working emulator is there:

a throw-away remote VNC linux desktop in a docker container

I am running most of my in-house infrastructure based on Docker these days…

Docker is a set of platform-as-a-service (PaaS) products that use operating-system-level virtualization to deliver software in packages called containers. Containers are isolated from one another and bundle their own software, libraries and configuration files; they can communicate with each other through well-defined channels.

All containers are run by a single operating-system kernel and are thus more lightweight than virtual machines.

Wikipedia: Docker

And given the above definition it’s fairly easy to create and run containers of things like command-line tools and background servers/services. But due to the nature of Docker being “terminal only” by default it’s quite hard to do anything UI related.

But there is a way. By using the VNC protocol to get access to the graphical user interface we can set-up a container running a fully-fledge Linux Desktop and we can connect directly to this container.

I am using something I call “throw-away linux desktop containers” all day every day for various needs and uses. Everytime I start such a container this container is brand-new and ready to be used.

Actually when I start it the process looks like this:

As you can see when the container starts-up it asks for a password to be set. This is the password needed to be entered when the VNC client connects to the container.

And when you are connected, this is what you get:

this is what you see after connecting to the desktop container by VNC

I am sharing my scripts and Dockerfile with you so you can use it yourself. If you put a bit more time into it you can even customize it to your specific needs. At this point it’s based on Ubuntu 18.04 and starts-up a ubuntu-mate desktop environment in it’s default configuration.

When you log into the container it will log you in as root – but effectively you won’t be able to really screw around with the host machine as the container is still isolating you from the host. Nevertheless be aware that the container has some quirks and is run in extended privileges mode.

Chromium will be pre-installed as a browser but you will find that it won’t start up. That’s because Chromium won’t start up if you attempt a start as root user.

The workaround:

“–no-sandbox” parameter for Chromium

Now get the scripts and container here and build it yourself!

housekeeping with NodeJS

When you are using or developing NodeJS applications and the Node Package manager (npm) over time a lot of old crusty libraries will accrue.

A lot means, a lot:

To have a chance to get on top of things and save space, try this:

npm i -g npkill 

By then using npkill you will get an overview (after a looong scan) of how much disk space there is to be saved.

Great tip!

an OS in your browser

So I leave this right here:

OS.js is an open-source JavaScript Web Desktop implementation for your browser with a fully-fledged window manager, Application APIs, GUI toolkits and filesystem abstraction.

It really does implement a lot of what an operating system UI and portions of the backends are supposed to be. It looks quite funky and there are applications to this. Of course it’s open source

I want all electron Apps to start existing there so I can call all of them with just a browser from anywhere.

If you want to give it a spin, click here:

artifact, noise removal and inpainting toolbox

Deep convolutional networks have become a popular tool for image generation and restoration. Generally, their excellent performance is imputed to their ability to learn realistic image priors from a large number of example images. In this paper, we show that, on the contrary, the structure of a generator network is sufficient to capture a great deal of low-level image statistics prior to any learning. In order to do so, we show that a randomly-initialized neural network can be used as a handcrafted prior with excellent results in standard inverse problems such as denoising, super-resolution, and inpainting. Furthermore, the same prior can be used to invert deep neural representations to diagnose them, and to restore images based on flash-no flash input pairs.
Apart from its diverse applications, our approach highlights the inductive bias captured by standard generator network architectures. It also bridges the gap between two very popular families of image restoration methods: learning-based methods using deep convolutional networks and learning-free methods based on handcrafted image priors such as self-similarity.

Deep Image Prior Paper

As usual there’s source code available to try out yourself. It even comes with a pre-configured docker jupyter notebook.

color assimilation grid illusion

The image [..] is a visual/artistic experiment playing with simultanous contrast resulting from other experiments these days. An over-saturated colored grid overlayed on a  grayscale image causes the grayscale cells to be perceived as having color.
The processing needed to create the above image happened along with unrelated but significant code improvements In the last couple of weeks. I have been visiting mitch – a prolific GIMP contributors for collaboration – and lots of progress has been – and is still – being made on babl, GEGL and GIMP.

original article
See the effect in a video

You can now play with this effect and experiment for yourself. Get Gimp and enjoy!

host GIT repositories painlessly

As people around me discuss what to go for in regards to manage their growing number of private GIT repositories I joined their discussion.

A couple of years ago I assessed how I would want to store my collection of almost 100 GIT private repositories and all those cloned mirrors I want to keep for archival and sentimental reasons.

An option was to pay for GitHub. Another option, which most seemed to prefer, was going for a local Gitlab set-up.

All seemed not desirable. Like chaining my workflows to GitHub as a provider or adopting a new hobby to operate and maintain a private GitLab server. And as it might have become easier to operate a GitLab server with the introduction of container management systems. But I’ve always seemed to have to update to a new version when I actually wanted to use it.

So this was when I had to make the call for my own set-up about 4 years ago. We were using a rather well working GitLab set-up for work back then. But it all seemed overkill to me also back then.

So I found: gogs.io

It runs with one command, the only dependency is two file system directories with (a) the settings of gogs and (b) your repositories.

It’ll deploy as literally a SINGLE BINARY without any other things to consider. With the provided dockerfile you are up and running in seconds.

It has never let me down. It’s running and providing it’s service. And that’s the end of it.

I am using it, as said, for 95 private repositories and a lot of additionally mirrored GIT repositories. Gogs will support you by keeping those mirrors in sync for you in the background. It’s even multi-user multi-organization.

code autocomplete with deep learning

When you are writing code the patterns seem to repeat every once in a while. Not only the patterns but also the occasion you are going to apply certain code styles and methods while developing.

To support a developer with this creative work the tedious and repetitious tasks of typing out what is thought can be supported by machine learning.

Chances are your favourite IDE already supports an somehow AI driven code autocomplete feature. And if it does not, read on as there are ways to integrate products like TabNine into any editor you can think of…

Visual Studio IntelliCode is a set of AI-assisted capabilities that improve developer productivity with features like contextual IntelliSense, argument completion, code formatting, and style rule inference.

IntelliCode augments existing developer workflows with machine-learning services that provide an understanding of code and its context. It’s applicable for C#, C++ (in preview), JavaScript/TypeScript (in preview), and XAML code today, and will be updated in the future to support more languages.

Visual Studio IntelliCode

Of course there are some new contenders to the scene, like TabNine:

TL;DR: TabNine is an autocompleter that helps you write code faster. We’re adding a deep learning model which significantly improves suggestion quality. You can see videos below and you can sign up for it here.

TabNine

Deep TabNine requires a lot of computing power: running the model on a laptop would not deliver the low latency that TabNine’s users have come to expect. So we are offering a service that will allow you to use TabNine’s servers for GPU-accelerated autocompletion. It’s called TabNine Cloud, …

TabNine

fiddle with .NET in your browser

There are a lot of different “fiddles”. There’s JSFiddle, SQLFiddle, HTMLFiddle, RegExFiddle, PythonFiddle, R-Fiddle, GoFiddle. There is even a page that curates a list of fiddles.

For .NET there’s one too. It supports C#, F# and VB.NET. For trying something quickly or sharing it online this is a nice way to do it:

Hello World C#
MVC even

retrofit an old printer to be available on the network

In 2007 I had become proud owner of a Samsung ML-2010 mono laser printer. It’s done a great job ever since and I can recall changing the toner just once so far.

So you can tell: I am not a heavy printer user. Every so often I gotta print out a sheet of paper to put on a package or to fill out a form. A laser printer is the perfect fit for this pattern as it’s toner is not going-bad or evaporating like ink does in ink-printers.

So I still like the printer and it’s in perfect working condition. I’ve just recently filled up the toner for almost no money. But – but this printer needs to be physically connected to the computer that wants to print.

As the usage patterns have significantly changed in the last 12 years this printer needs to be brought into todays networked world.

Replacing it with a new printer is not an option. All printers I could potentially purchase are both more expensive to purchase and the toner is much more expensive to refill. No-can-do.

If only there was an easy way to get the printer network ready. Well, turns out, there is!

First let’s start introducing an opensource project: CUPS

CUPS (formerly an acronym for Common UNIX Printing System) is a modular printing system for Unix-like computer operating systems which allows a computer to act as a print server. A computer running CUPS is a host that can accept print jobs from client computers, process them, and send them to the appropriate printer.

Wikipedia

A good, cheap and energy-efficient way to run a CUPS host is a Raspberry Pi. I do own several first-generation models that have been replaced by much more powerful ones in the previous years.

So I’ve taken one Raspberry Pi and did the set-up steps: Installing the Raspberry Pi Print Server Software.

And now – what did I get?

I got a networked Samsung Laser Printer. No thrills, no problems at all.

the CUPS web interface
the printer shows up on Linux (Ubuntu here)
on iOS and macOS the printer magically appears
on Windows 10.

TAICHI: opensource computer graphics library

I am following the proceedings of ACM SIGGRAPH conferences for more than 20 years now and with the recent years development in computational capacity it seems that many more algorithms and ideas make it to an application near you.

Take this one contribution by Yuanming Hu for example – the Taichi open source computer graphics library:

Taichi is an open-source computer graphics library that aims to provide easy-to-use infrastructures for computer graphics R&D. It’s written in C++14 and wrapped friendly with Python.

Yuanming Hu has been working on the development of Taichi since his third undergrad year (2016), mainly in his spare time. He would like to thank Prof. Toshiya Hachisuka and Prof. Seiichi Koshizukafor making possible his internship at UTokyo, where the initial parts of Taichi were developed.

Taichi: About

Also interesting, trivia about the name:

Tool: Partition Recovery and Undelete – Testdisk

Mass storage hardware breaks all the time. Sometimes it’s hardware that breaks, but sometimes it’s the software that breaks. If it’s the software (or own talent) that made the data go boom, TestDisk is a tool you should know about.

DISCLAIMER: If the data you are trying so recover is actually worth anything you might want to reserve to a professional data recovery service rather than trying to train-on-the-job.

Apart from the availability of pre-compiled packages for most operating systems you can also grab a bootable LiveCD when everything seems gone and lost.

The process itself is rather exciting (if you want the data back) and may require a fresh pair of pants upfront, throughout and after.

Thankfully there’s a great wiki and documentation of how to go about the business of data recovery.

TestDisk is powerful free data recovery software! It was primarily designed to help recover lost partitions and/or make non-booting disks bootable again when these symptoms are caused by faulty software: certain types of viruses or human error (such as accidentally deleting a Partition Table). Partition table recovery using TestDisk is really easy.

  • TestDisk can
    • Fix partition table, recover deleted partition
    • Recover FAT32 boot sector from its backup
    • Rebuild FAT12/FAT16/FAT32 boot sector
    • Fix FAT tables
    • Rebuild NTFS boot sector
    • Recover NTFS boot sector from its backup
    • Fix MFT using MFT mirror
    • Locate ext2/ext3/ext4 Backup SuperBlock
    • Undelete files from FAT, exFAT, NTFS and ext2 filesystem
    • Copy files from deleted FAT, exFAT, NTFS and ext2/ext3/ext4 partitions.

TestDisk has features for both novices and experts. For those who know little or nothing about data recovery techniques, TestDisk can be used to collect detailed information about a non-booting drive which can then be sent to a tech for further analysis. Those more familiar with such procedures should find TestDisk a handy tool in performing onsite recovery.

And if you give up, think about writing an article of you actually digging deeper:

Wireless Network Mapping – data source and data sink

When you work with wireless networks and you do programming and mobile app development that works with things like user location you might find this useful.

Take thousands of users and you’ve got the worlds wifi networks mapped…

WiGGLE (Wireless Geographic Logging Engine) is a project which takes wireless network data + location and puts it into a big database. On top of storage it’s giving you access to that data.

We consolidate location and information of wireless networks world-wide to a central database, and have user-friendly desktop and web applications that can map, query and update the database via the web.

https://wigle.net/faq

So what’s my use-case? Apart from the obvious I will make use of this by finding out more about those fellow travelers around me. Many people probably to the same as me: Travel with a small wifi / 4g access point. Whenever this accesspoints shows up in scans the path will be traceable.

I am curious to see which access point around me is in the million-mile club yet…

full website screenshots from your commandline

Think of this: You want to capture a whole, multi-scroll-pages, web-page into one image.

This can be difficult without the right tools. It surely will be a lot of work to accomplish a 10th of thousand pixel height screenshot put together from multiple single screenshots…

CutyCapt is there to help! It’s a command line tool encapsulating the very powerful WebKit browser engine to render a full page and then create a single file screenshot of the whole page for you.

By example, this is what it did when told to screenshot this website:

PixelFed – Federated Image Sharing

In search of alternatives to the traditional centralized hosted social networks a lot of smart people have started to put time and thought into what is called “the-federation”.

The Federation refers to a global social network composed of nodes that talk to each other. Each of them is an installation of software which supports one of the federated social web protocols.

What is The Federation?

You may already have heard about projects like Mastodon, Diaspora*, Matrix (Synapse) and others.

The PixelFed project seems to gain some traction as apparently the first documentation and sources are made available.

PixelFed is a federated social image sharing platform, similar to instagram. Federation is done using the ActivityPub protocol, which is used by Mastodon, PeerTube, Pleroma, and more. Through ActivityPub PixelFed can share and interact with these platforms, as well as other instances of PixelFed.

the-federation

I am posting this here as to my personal logbook.

Given that there’s already a Dockerfile I will give it a try as soon as possible.

WiFi QR Code Generator

Whenever we arrive at a place that we have not been before it is important to get properly connected to the internet.

Finding wifi SSIDs and typing passwords is tedious and prone to errors. There is an easier way of course!

The owner of the wireless network can generate a QR code that you can easily take a photo of and your phone will automatically prompt you to log into the wireless network without you having to type anything.

On your phone it looks like this:

To generate these QR codes that contain all information for visitors/new users to connect this simple tool / online generator can be used:

Ever wanted to create a cool QR code for your guests? But never wanted to type in your WiFi credentials into a form that submits them to a remote webserver to render the QR code? QiFi for the rescue! It will render the code in your browser, on your machine, so the WiFi stays as secure as it was before (read the code if you do not trust text on the internet :-))!

Qifi.org

Don’t worry: your access point information is not transferred over the internet. As this is open source at the time of writing the data was held in HTML 5 local storage on the local browser only and not transferred out.

bridge the openvpn-status.log to MQTT

For big parts of my VPN needs I use OpenVPN. Especially on iOS devices the deep integration just works. Even to a degree that you enable the VPN once and the device will transparently keep it up / reestablish connections when required.

OpenVPN protocol has emerged to establish itself as a de- facto standard in the open source networking space with over 50 million downloads. OpenVPN is entirely a community-supported OSS project which uses the GPL license.

VISIT THE OPENVPN COMMUNITY

I am using the dockerized version of OpenVPN. From there I’ve got several ways to get telemetry data (like connections, traffic, …) out of it. One way is the management interface provided by OpenVPN. Another way is by using the default openvpn-status.log file.

Since the easiest way out-of-the-box was to use the logfile I sat down and wrote a little 2mqtt bridge for the contents of the logfile.

It’s also dockerized so you can easily set it up by pointing the openvpn-status.log to the right volume/mount-point.

When done it’ll produce MQTT messages like this:

The set-up and start-up is rather simple:

docker run -d --restart=always --volume /openvpnstatus2mqttconfiglocation/:/configuration --volume /openvpnstatusloglocation/:/openvpn openvpn-status2mqtt

MQTT Broker, Topic-Prefix and so on are configured with the .json configuration file found along the project.

Of course everything I wrote is available on GitHub as open-source.

The immediate outcome of this is that with the always-on VPN I am now getting statistics about, for example, the data consumption of my iPhone.

The big traffic spike at 1 AM is the backup that my iPhone does every night. Very interesting also how often the connection is closed and opened again even without me using the phone…

online archeology: to be young and online in 1987

Archive.org is the place to find out about our common internet past. It’s the another project, besides Wikipedia and …, that started it’s life with a bold claim it so far holds true to:

The Internet Archive, a 501(c)(3) non-profit, is building a digital library of Internet sites and other cultural artifacts in digital form. Like a paper library, we provide free access to researchers, historians, scholars, the print disabled, and the general public. Our mission is to provide Universal Access to All Knowledge.

Internet Archive: About IA

And when you freely roam around the archive you will find many gems, like this one:

Another recommendation / starting point on the archive would be Computer Chronicles:

There’s countless hours of material to dig into and be amazed!

terminates the calling process if buffer is not a valid userspace pointer.

How to build security into your software? It’s always simple to find examples where things gone wrong. Where security was compromised and things did not work out as the software authors envisioned.

As always there are new concepts and operating systems being implemented.

A particularly interesting example of security software design can be observed here:

Fuchsia is an open source capability-based operating system currently being developed by Google.

In contrast to prior Google-developed operating systems such as Chrome OS and Android, which are based on the Linux kernel, Fuchsia is based on a new microkernel called Zircon. The name Zircon refers to the mineral of the same name.

Google Fuchsia

So you now know what Fuchsia is. Now on to the actual example. For this we have to take a look into the developer documentation of Zircon:

So this describes a method to get random numbers from the systems cryptocraphically-secure-random-number-generator (CPRNG). It takes a pointer to a memory location as a parameter.

Now. What’s secure about that? It’s the behaviour of the method when it is encountering an unsecure situation:

It’ll kill the calling process when the pointer is not valid.

automated downloads

Hmm… I’ve set-up a script to automatically download a TV show about a year ago and just remembered it…

Apparently 1 year of this show is 167 Gbyte…

For completeness the download script – ignore my bad scripting:

#!/bin/bash

# parameter 1: month
# parameter 2: from day
# parameter 3: to day
# parameter 4: year

# data -dmonday +%d

next_monday=$(date -dmonday +%d)
next_monday_month=$(date -dmonday +%m)
next_monday_year=$(date -dmonday +%y)

previous_monday=$(date -d'monday-7 days' +%d)
previous_monday_month=$(date -d'monday-7 days' +%m)
previous_monday_year=$(date -d'monday-7 days' +%y)

next_friday=$(date -dfriday +%d)
next_friday_month=$(date -dfriday +%m)
next_friday_year=$(date -dfriday +%y)

previous_friday=$(date -d'friday-7 days' +%d)
previous_friday_month=$(date -d'friday-7 days' +%m)
previous_friday_year=$(date -d'friday-7 days' +%y)

for i in `seq 1 7`;
do
        day=$(date -d'today+'$i' days' +%d)
        month=$(date -d'today+'$i' days' +%m)
        year=$(date -d'today+'$i' days' +%y)
        wget -c "https://rodlzdf-a.akamaihd.net/none/zdf/"$year"/"$month"/"$year$month$day"_sendung_dku/1/"$year$month$day"_sendung_dku_3328k_p36v14.mp4"
done

IP-over-DNS

Picture yourself in this situation. You connect to a network and nothing works. Except for this:

It is quite common to have DNS working in networks while everything else is not. Sometimes the network requires a log-in to give you access to a small portion of the internet.

Now, with the help of a tool called iodine, you can get access to the full internet with only DNS working in your current network:

iodine lets you tunnel IPv4 data through a DNS server. This can be usable in different situations where internet access is firewalled, but DNS queries are allowed. 

It runs on Linux, Mac OS X, FreeBSD, NetBSD, OpenBSD and Windows and needs a TUN/TAP device. The bandwidth is asymmetrical with limited upstream and up to 1 Mbit/s downstream. 

iodine

Setting it up is a bit of work but given that you are anyway having access to a well connected server on the free portion of the internet it can be easily done.

Of course the source is on github.

making ICs at home

Try to wrap your head around this: There are people out there that take the term “Maker” to new levels. People Like Sam Zeloof. He went out and created his very own integrated circuit designs and then he built them. Like the actual silicon, the die, the bonded chip, the IC. The real thing.

Be inspired:

I am very excited to announce the details of my first integrated circuit and share the journey that this project has taken me on over the past year. I hope that my success will inspire others and help start a revolution in home chip fabrication. When I set out on this project I had no idea of what I had gotten myself into, but in the end I learned more than I ever thought I would about physics, chemistry, optics, electronics, and so many other fields. Furthermore, my efforts have only been matched with the most positive feedback and support from the world; I owe a sincere thanks to everyone who has helped me, given me advice, and inspired me on this project. Especially my amazing parents, who not only support and encourage me in any way they can but also give me a space to work in and put up with the electricity costs… Thank you!

Sam Zeloof

Decoding history, the hard way (and with machine learning)

Imagine you’ve got this ancient piece of technology in front of you. You clearly understand how the hardware works and you are even able to emulate the hardware on your modern-world computer.

Unfortunately hardware is only one half of the story. Software is the other half. And software at this time of the past was burned into chips which do not easily give their secret software away.

But let’s start with the hardware:

The IBM 5100 Portable Computer is a portable computer (one of the first) introduced in September 1975, six years before the IBM Personal Computer. It was the evolution of a prototype called the SCAMP (Special Computer APL Machine Portable) that was developed at the IBM Palo Alto Scientific Center in 1973. In January 1978, IBM announced the IBM 5110, its larger cousin, and in February 1980 IBM announced the IBM 5120. The 5100 was withdrawn in March 1982.

When the IBM PC was introduced in 1981, it was originally designated as the IBM 5150, putting it in the “5100” series, though its architecture was not directly descended from the IBM 5100.

And now on to the software:

The IBM 5100 portable computer came with some of its built-in programs stored in a read-only memory called the “non-executable ROS”. (ROS = “read-only storage”.) In contrast with the “executable ROS”, which supplies instructions to the 5100’s processor directly, the non-executable ROS is accessed using sequential I/O operations, a bit like a tape.

Most notably, the non-executable ROS holds the interactive interpreters for the APL and BASIC programming languages. These are not “native” 5100 programs but were expressed instead in System/370 mainframe and System/3 minicomputer machine code respectively. The 5100 runs emulator programs for those computers in order to host the interpreters, so perhaps it’s just as well that the non-executable ROS is non-executable.

DATA

So this write-up is all about how the bits where pushed to the screen and recorded as pictures of the said screen. The characters in these pictures then where analyzed and with the help of machine learning the data could be successfully extracted. It is mind-boggling. And it is all on Github.

Bitmap & tilemap generation with the help of ideas from quantum mechanics

You can get a grasp at the beautiful side of science with visualizations and algorithms that output visual results.

This is the example of producing lots and lots of complex data (houses!) from a small set of input data. It is widely used in game development but also can be helpful to generate parameterized test and simulation environments for machine learning.

So before sending you over to the more detailed explanation the visual example:

This is a lot of different house images. Those are generated using a program called WaveFunctionCollapse:

WFC initializes output bitmap in a completely unobserved state, where each pixel value is in superposition of colors of the input bitmap (so if the input was black & white then the unobserved states are shown in different shades of grey). The coefficients in these superpositions are real numbers, not complex numbers, so it doesn’t do the actual quantum mechanics, but it was inspired by QM. Then the program goes into the observation-propagation cycle:

On each observation step an NxN region is chosen among the unobserved which has the lowest Shannon entropy. This region’s state then collapses into a definite state according to its coefficients and the distribution of NxN patterns in the input.

On each propagation step new information gained from the collapse on the previous step propagates through the output.

On each step the overall entropy decreases and in the end we have a completely observed state, the wave function has collapsed.

It may happen that during propagation all the coefficients for a certain pixel become zero. That means that the algorithm has run into a contradiction and can not continue. The problem of determining whether a certain bitmap allows other nontrivial bitmaps satisfying condition (C1) is NP-hard, so it’s impossible to create a fast solution that always finishes. In practice, however, the algorithm runs into contradictions surprisingly rarely.

Wave Function Collapse algorithm has been implemented in C++PythonKotlinRustJuliaGoHaxeJavaScript and adapted to Unity. You can download official executables from itch.io or run it in the browser. WFC generates levels in Bad NorthCaves of Qudseveral smaller games and many prototypes. It led to new research. For more related workexplanationsinteractive demosguidestutorials and examples see the ports, forks and spinoffs section.