Beautiful Luxembourg on Wheels


I wanted to share my own point of view of Luxembourg-city. Here is a video showing the beauty, the fun and the dangers through the glasses of a bike commuter in Luxembourg.

Have fun watching!


P.S.: don’t miss another article and video Luxembourg to Howald done quicker

Video Telemetry: a recipe

A friend of mine asked me how I made the short film : Luxembourg Kirchberg to Howald done quicker. So I thought I would as well share it with everyone.

More specifically, how to display a real time map and/or speed dashboard on top of the footage.

Many possibilities to do it and it really depends on how much time you want to spend doing it, what device(s) you use to capture data, and what final result you want.

Easy and automatic

The simplest and easiest way is to use the wonderful App called Vidometer, by HitCase, available on Apple iPhone. Hitcase also sell state of the art action cases for iPhone that are shock-proof and waterproof, among other accessories like all sorts of  mounts for instance. That Vidometer App allows you to record your action in a video, and the result will be a video with user-customizable maps and speeds displayed on top.

There is an article in french which introduces on video telemetry. If you’re interested, you can give it a read.

Incrustation de données gps dans une vidéo

Advanced technique

Now let’s go a little bit further into how I made the video. Not using Vidometer.

The principle is to record GPS data or (any) other data in real time with a device (in my case an iPhone, but it could be a dedicated GPS device, and or some activity tracker, whatever), and use that recorded data to match it with a video footage. The collected real-time (GPS position, heartbeat, whatever) data would be graphically represented (i.e. on a map, a speedometer, a dash) and that piece of graphics would be then merged on top of the original video footage.

Here is how I do it. There are probably many other ways, and better ways that I haven’t discovered yet. Any comment and advice are welcome!

Recording video and GPS data

  1. The footage was shot with the wonderful GoPro Hero 4 Session. I chose this device against a classic GoPro Hero 4 because of the small form factor (just a small cube) and the fact that it’s waterproof without a case. Although the performance and quality is a little under what’s possible on a “big” GoPro, the product is really better than any competitors on the market (for this size). The camera is mounted to the bike’s handlebar. So far, the camera has never failed me. Never stopped recording in the middle of the action no matter the rain and the shocks.
  2. At the same time, the commute was recorded with Strava. It is a social App that allows to record all your efforts (Running, riding the bike…) and to virtually compete with other “athletes”. The App is really cool, fast, easy to handle and featured. Among cool features are the awesome “segment” function which allows to compete on small parts that you go through a lot; another cool feature is the flyby, which shows who of other Strava athletes you came across during an effort.

Creating the dash overlay

  1. You’ll need a chroma key video. Here is how to do it in Apple Final Cut Pro X (FCPX). Start FCPX, create a new Project. In the empty storyline, drag a background generator, make it plain, green or blue. Select the new clip in your storyline, hit CTRL+D, enter the new duration (must exceed the total duration of your GPS track recording, of course). Then export the video.
  2. Open your recorded activity in Strava, decide a starting point and an end point that fit your video, and trim the tracklog. The easiest is to locate places where you stopped. This makes it easier to synchronize later.
  3. Export the GPS tracklog in Strava. To do so, just add “/export_gpx” to the URL of your Strava activity. For instance : The export will produce a GPX file which is a standard file for GPS tracklogs. Or use the wrench menu, and export GPX.
  4. Download and install the Excellent shareware called DashWare. You’ll need a Windows PC or a PC Emulator (such as Parallels, Oracle VirtualBox or VMWare Fusion) in order to perform this task. I personally use VMware Fusion out of habit, but Oracle VirtualBox is equally good for the task, and it’s free and open source.
  5. In Dashware, load the video file (chroma key video) you previously exported from FCPX, and then load the GPX Track. Then synchronize the GPS track with the Chroma Key video, define start and end, and chose your Dash type (avoir to use the green color in your Dash if your Chroma Key video is green). For details, just have a look at the very good video tutorials made by Dashware. Then export the video. The result will be a green video with an animated dash on it (i.e. speedometer). Note: you can also import all sorts of other data such as heart-rate and add as many dashes as you want on your screen.

Merging using Chroma Key

There is a very good guide at Apple that describes how to use Chroma Key. Check it out. Basically here is how to proceed.

  1. Create a new empty project in FCPX
  2. If you use a GoPro camera, the action video footage is split in 12 minutes clips (by default). Just import all the clips into the FCPX event and add all of the clips to the Project’s empty storyline. Make sure they are in the right consecutive order, then select all of them (keyboard shortcut Apple Key+A), then CTRL+Click on the selected clips to show the context menu, and choose “create compound clip“. Name it “Action Footage Clip“, for instance. Then remove everything from the storyline to make it empty again (Apple Key + A, then Delete/Backspace). The compound clip you just created is now available in the browser and remains so even if you empty the timeline.
  3. In the Timeline, add the foreground clip (Dash clip you just created with DashWare) to the primary storyline.
  4. Your video compound clip “Action Video Footage” in the story line just under the Dash Clip.
  5. Select again the Dash clip (the foreground clip), and chose the “keyer” effect using the Effect button. Drag the effect on top of the Dash Clip. The “keyer” effect will detect the “green” color automatically and remove it. Otherwise, you will need to adjust it manually, as explained in the guide.

The Final Cut

  1. The foreground and the background on the timeline are linked together. Make sure that they are both well synchronized by dragging the background right or left according to your needs. to be sure to synchronize the Dash Clip and the Action video footage properly, the best way is to locate places where you stopped. There, the speed displayed on the Dash must be 0. Just beware that there is a little latency on speeds recorded by GPS, especially on Smart Phones.
  2. Once you’re happy with the synchronization of your clips, just create a new Compound Clip out of them by selecting them both, CTRL+Click on them, and “create compound clip”. Then empty the timeline again, and add the new compound clip in the Storyline.
  3. From here you can cut parts you don’t want, add transitions, effects, titles, music…

Luxembourg Kirchberg to Howald done quicker

2016-06-02 21_53_49

Remember QDQ ? Quake done Quicker ? anyone ? (I’m too old…)

Anyway. Here is Kirchberg-to-Howald done Quicker. In 21 minutes exactly. In traffic. From the far eastern side of Luxembourg-City called “Le plateau de Kirchberg” (see another article here: Kirchberg ) to the far southern side of Luxembourg city Howald.

Distance: 10.3 km (in traffic)
Average Speed: 28.4 kph (max Speed: 56.2 kph)
Fun: 100%

FlyBys: Tzet, Tyrone, serge

Complete downloadable GPS TrackLog and statistics can be found on Strava.


And here is, of course, the video footage. Don’t worry, I made it short. It is only 1 minute 38 seconds long 🙂


Quad for sale

french Pour une version en Français de cet article, cliquer ici.

Price: 11 300€

Vehicle type: Quad, Four-wheel Drive (AWD)
Engine: 800 cm³
fuel type: gasoline
Mileage: 2500 km
color: Blue
Tires: 90% new
power: 37 kW
technical checkup valid until: January 2017
Cooling: liquid
Damaged: none found
First country of registration: Germany, 2013
Current location: Lithuania, EU

Others/specifics: integrated electric starter, stereo radio, disk brakes, AWD (4×4), vehicule papers and registration, complete maintenance file, luggage carrier.

Remarks: three-cylinder engine, DOHC 812 cm³
4×4 with differentials lock; 5 speed transmission
Max speed 90 km / h.
Quickly removable roof, stainless steel sills, 4 LED floodlights. In perfect condition. Used as expo model in German showrooms.

Transportation / delivery: shipping possible for approx. 300€

Please leave a comment if interested.



Action Cams

Hello there !

** update March-2016 — There will be no review of the product because I sent it back to Amazon (refund, no question asked) shortly after I got it. The main reason being that the camera would simply stop recording in the middle of the “action”. Unfortunately, at the moment my life doesn’t offer me the luxury of having the time to investigate why a brand new product doesn’t work as expected, so I sent it back. Might be because of the brand new 128GB SD-XC memory card purchased separately (yet it fits the minimum requirements). Who knows. Maybe the doubt on the memory card would not exist if Panasonic bundled one in the box. The other drawback of the HX-A1ME, which is difficult to evaluate before you buy (a few reviews actually address that aspect), is the quality/limitations of the software on the iPhone; the App looks very “clumsy”, is unstable, not fast, not intuitive, bad ergonomy, poor design, doesn’t integrate very well; nothing you’d expect when you use an iPhone anyway. Such a software, I normally throw away; except you need it; doing without brings other limitations. This second reason isn’t enough in itself to ship the HX-A1ME back, but it just adds up; worth mentioning.  But in a nutshell, the product fits my needs in terms of size, weight, video quality (compression/bitrate OK for me), water resistance. The battery doesn’t hold long but that was by design (ie. small battery comes with the relatively cheap price and light weight and small size). All in all a good product, if only it worked. Conclusion : my helmet is now 40 grams lighter 🙂 **

2014 was the year of the wearables. 2015 being definitely *the year* of the wearables (hem…), I got interested in an Action Cam. Well. For sure 2016 will be the year of wearables mass adption 😉

So if even journalists say it, let’s give it a shot. Would be a shame to miss that train.

For my specific use (that is every day bike commute), there are a few constraints.

  • needs to be tiny, lightweight and in a shape of a bullet (to be able to strap it to the helmet without looking like a deer with only one horn)
  • needs to be waterproof (to a certain extent), shockproof, and dustproof. Things can get pretty ugly when you commute everyday whatever the weather.
  • needs to be simple to operate. In winter when you wear gloves, you don’t want to have to manipulate tiny buttons. Switch on, it records, switch off, it stops.

I have learnt from my reasearch that there are a few aspects that don’t necessarily pop-out at first sight. For instance :

  • the bitrate (BR). Expressed in mbps. Most of people concentrate only on video image resolution (or HD-720p, Full-HD 1080p…). But the resolution alone means nothing, although it is the main marketing argument. In fact, recorded images are compressed to create a video stream; the compression level impacts the size of the data and the bitrate. The more you compress (lower bitrate), the more image details are lost. For instance, a Full-HD 1080p video stream highly compressed (eg. with a low bitrate) will look like as “bad” or worse than a HD-720p video. Recording a 1080p video requires a higher bitrate than recording a 720p video if you want to keep the same sharpness/quality. The higher the bitrate, the better. The downside of that is: recording at higher bitrates require more computing power, takes more space on the memory card, and drains the battery more. That doesn’t go well with compact devices. When chosing a camcorder, the bitrate must be verified depending of what you want to do with your video (internet streaming on a 5″ mobile or watching at home on a big TV screen?). The table below shows the recommended minimum bitrates per resolution and framerate (ie. for Youtube); that’s for online streaming (mostly on mobile phones or tablets. In my opinion, the recommendation is a bit weak for “action” and video post processing (ie. iMovie, Final Cut Pro X). Not only the resultion, but the framerate (fps, frames per second) too has an impact on the minimum bitrate required to record a good quality video, as you can see below. What’s more, both the encoding format (codec, ie. H.264 being the most common today) and the bitrate have an impact on the quality of the recorded video (for the record, future encoding technology, ie. H.265, will permit the same video quality for bitrates 50%-65% lower than the universally used H.264 compression technology).
Recommended bitrates for streaming services (Youtube)
Recommended bitrates by
  • Hardware and Software. Optics (lens), size of the MOS sensor, encoding chip and encoding software (multipass, CBR/VBR…) all have an impact on the final quality of the recorded video. It is a Jungle. My advice : read reviews (,,, etc…) and watch uploaded video samples in order to make an opinion for yourself.

Here is the document I made to help me choose the perfect Action Cam 🙂

Click on the image to enlarge the document

Other things.

  • Stabilizer. Some devices integrate an image stabilizer which basically keeps the recorded video stable in shaky situations. The stabilizer (and the quality and setup of the chip/software which does stabilization) has a great impact on the recorded video. Stabilization almost always gives the Jelly-effect or Jell-o, the impression to fly or to be sitting on jelly or on the back of an elephant. Please note that some devices don’t allow the stabilizer to be disabled at all, which can be a problem. Video stabilization can be done later by using after processing software (PC, Mac…)



My final choice (and in my opinion the second most suitable product for my needs) is the Panasonic HX-A1ME, which can be found on Amazon (France, Germany) for less than 150€. The second choice (best of all, I think) would have been the Replay HD Prime X because of the higher bitrate, better fps and better battery life, but this model is way over my budget. Besides, the Panasonic is smaller and half the weight of the Replay XD.

Commute to work with snow

Hey Folks !

Today is a great day. It is snowing 🙂


IMG_3809 IMG_3810

I’ll try to share my impressions. Please note that some of the charts below are vectorial (SVG), you can zoom in them.




Here is the planning.

  • Take my 4-year old son to School, safely.

That went all right, although we had to change itinerary, because my son had trouble with his 16″ wheels on 7 cm of snow in Kirchberg. The bicycle tracks and paths were free of snow, and that’s awesome too.


  • Commute the rest of the way to Luxembourg-City, carefully, but not too slow.

That went all right as well, although slower than usual.

Today’s track, commute from Kirchberg to Luxembourg-City, with a stop at school


Below, a few charts.


Shows the difference between a typical (fast) commute and a commute with snow and with a stop at school on the way (hence the distance difference)
Stats from Trails App on iPhone
Stats from Trails App on iPhone