After some years of entrepreneurship, I wanted to start sharing some things I learned. Some are just bits of data I extracted from a particular problem, others are more in-depth analysis of technical or business problems. There's a bit of everything, half for my later self to remember, and half for whomever may find it of use.
Welcome to my blog!
Sebastien DUMETZ
I use Jekyll a lot at work for various static sites. Throughout it, I’ve developped some handy plugins. While Jekyll’s plugins system is easy and powerful to use, the doc lacks some info on helpers functions, right_way™ to parse arguments, etc… Here’s a short list, half for myself to remember, half for others to learn.
CustomEvent in browser-JS is a rarely used feature, while it’s ubiquitous in it’s server-side counterpart. It looks like an elegant solution to dispatch state changes, redux-style.
The HTML5 VideoElement allows for codecs informations in the type property. For once, even safari seems to happily support it. How is it important? Because browsers will choose the first input they can play solely depending on the type property (or file extension, if absent). Once they make the wrong choice (i.e. A too high level mp4 video for iOS/ a low end android), they’ll just hang there forever.
I’ve fiddled a bit recently with self-made HTML5 video players. While it’s easy to use and now widely compatible, I’ve had some trouble encoding videos. So here is my cheat sheet for mobile-first video distribution in 2017, including an in-depth look into mp4/webm performance.
I started using web workers for real-worl loads a few weeks ago and like many before me, I found it to be quite easy to use, but a real pain to debug. I’ll gather my thought about them for later use.
Like many, I was really enthousiast when the Leap motion was unveiled some years ago. At last, a company that emphasized on gesture recognition’s main problems : Speed and precision. Like most, I have been disappointed. Still not fast enough, still not precise enough. There is still not much to do in the land of gesture control. Or is there?
In previous post, I stated how I made a video player capable of reading a file from back to front. However I’m quite a beginner in video encoding and I felt there was improvements to be made.
I’ve recently found myself in need of a library to read evdev events. Usually, the X server will retrieve those events, parse them and send them to the concerned X client. In my case though, I needed xpad events from a gamepad. The only existing way to get them through X is the joystick driver, but it has been designed to control X server with a controller instead of a mouse.
I’ve recently faced an unexpected challenge in trying to read (decode & display) a video backward at normal speed. For someone who don’t know shit about video encoding, it looks like it should be as straightforward as calling video.previousFrame()… except it’s not. Let’s see why and how we worked around this to create a new generation of holographic applications.
I’ve found myself in need of a large sliding sensor. Many solutions exists for small sizes, inspired from ipod’s great capacitive wheel (DIY ones). However, when it comes to large size sensors, I found myself in lack of good references. Here is how I made a 15cm wide capacitive touch wheel.
One of the big wins of svg for the web is animation. It’s not as important now that we have canvas that works for nearly everything, but there is one thing really easy with SVGs and a real pain with canvas : Moving an object along a path.
Sebastien Dumetz
Co-founder of holusion , acting Product manager. I create new hardware and software tools to change digital user experience.
Dev Projects
