Low-Latency Live Streaming your Desktop using ffmpeg

I recently bought myself a projector, which I installed in one corner of the room. Unfortunately I didn’t buy a long enough HDMI cable with it, so I could not connect it to my desktop computer and instead used my loyal ThinkPad T60 for playback. But I also wanted to be able to play some games using the projector, for which my laptop wasn’t beefy enough. So I thought, why not just stream the games from my desktop computer to the laptop?

In this post I will explore how to stream 720p (or any quality for that matter) from one computer to another using ffmpeg and netcat, with a latency below 100ms, which is good enough for many games. TL;DR; If you don’t care about the technical details, just jump to the end of the post to try it out yourself.

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Fixing Full-HD VGA support for the Epson EH-TW5200 Projector

If you happen to own an Epson EH-TW5200 projector, you might have experienced problems setting Full-HD (1920×1080) resolution using a VGA connection under linux. When I set the resolution to Full-HD, the whole screen would stay completely black. This is just a quick fix for the other 4 people that might have this problem.

The difference between the original modeline and the new one is the vertical refresh rate: The projector proposed 60.02 Hz via EDID, and the new modeline is just a tad slower, using 59.94 Hz. I was connecting a ThinkPad T60 to the projector, so the problem might also be the RAMDAC of the laptop, something about blank phases, who knows.

 

Homeserver Upgrade: Odroid XU3-Lite Setup on a SD-Card

I recently bought a new home server, the Odroid XU3-Lite to replace my poor man’s home server I called the thin-server, to run CherryMusic and the like.

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That little ARM machine is a beast in the size of a cigarette pack, featuring a total of eight CPU cores, an ethernet port and most importantly an USB 3.0 port to connect an external hard drive. It also comes with a plastic case, with a small fan inside and a PSU that is strong enough to power external hard drives connected to the USB ports. I ordered the smaller “Lite” version, which has a slightly lower CPU clock rate, but costs a lot less than its bigger brother.

In this post I’ll guide you quickly through the installation process of the ubuntu image on a micro SD-Card, how to make use of all the space on the microSD card and how to secure this little fellow a little after the installation of the image.

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How to add USB Gamepad support for your Android phone or tablet

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I was almost at the point to buy a playstation or xbox controller to use with my tablet, since they seem to be supported out-of-the-box. But actually I still have an old USB controller lying around, which would be more than good enough for playing some games. Interestingly my gamepad did in fact work partly, but only the left analog stick and one or two buttons, and the rest did not. My hacker spirit told me that this must be fixable somehow.

So I started hacking around and added support for my old USB gamepad for my android tablet. In this post, I’ll show you how I did it and how you can to add support for any gamepad to your phone or tablet as well!

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Coders’ forbidden vocabulary

I often have to read a lot of code from other people that is not exactly well written or easily understandable. I am working on several different projects; some open-source for fun & giggles and some closed-source for money & fame. I just noticed that the biggest problem in understanding other peoples code is not about things you could easily measure, like code quality in the sense of code formatting standards or the language that it is written in. Naming of constants and variables make all the difference for understanding the code others have written.

forbiddenvocabularyI realized, that there are some words which should just be forbidden to use on their own. They are too broad or just don’t add any valuable information. I am also very sorry that these following examples contain PHP code, but this is where examples for doing things wrong are easily found. Most of the example code listings are not good practice in other senses as well, but that’s not what this post is about; It’s about the kind of readability which applies to all programming languages.

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How touch screens turn people into zombies or why keyboards are irreplacable

I just wanted to finish a draft blog post using my tablet, since after all, it’s a full blown computer. It has more than enough horsepower to run virtually any writing application. But right after I began to type in letter by letter, I realized that touch screens make you lazy. So lazy, that the blog post would have become much shorter than I wanted it to be. Additionally it would have included strange auto-completion artifacts and misplaced punctuation not resembling my usual writing style. Let’s explore the brave new world of touch screen computing, why touch screens suck and how they make us to internet zombies.

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The “Matrix Code” in your linux terminal using python and curses

Everybody knows the code on the screens in the movie the matrix. You can see it for example when the character “cypher” talks to “neo” somewhen in the night, and the green letters fall down on those second-hand dell screens behind them. Funky. I want that too.

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I’ve written a python program that uses curses to create a similar looking animation and just now cleaned up the code a bit and made sure it runs in python 2 and 3. You can get the source code on github and there’s a screenshot and a short explaination after the break…

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PyLint and Pep8 validation in geany

If you’re into python, but don’t know about PEP8 or PyLint, you should find out right now. And because pep8 and pylint are great, but it’s hard to force yourself to use them all the time, lets integrate them into geany, a fast and lightweight IDE.

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Using a Raspberry Pi to connect a third display over LAN

I’ve received my rPi a while ago, but never wound up doing much with it. Recently I have received another screen which is a little older, but still features a DVI input. Since developers can’t have enough screen space and my laptop has only one VGA output, I decided to use the raspberry pi as my ethernet-to-DVI adapter.

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This how-to is composed of two parts, first I explain how to get synergy up and running, and then how to set up your VNC to help the illusion that everything is happening on the same computer.

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3to2 by hand – back porting python 3 to python 2

As mentioned in an earlier post, I’m currently writing a music streaming server in python. As I wanted to go with the newest thing available, I wrote it in python 3. Unfortunately the application server we rely on, cherrypy, is only packaged for python 2 in most distributions! Even worse, even if the packages were installed for python 3, it would not run, since I relied on python 3.3 features.

Since this keeps my program from being used in the world, I decided to backport it to python 2. For me it was very important, that the code would not get any uglier by doing so, so I started writing a replacement module.

Here’s a collection of useful code snippets to help you making your software python 2 / 3 compatible.

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