Leap Motion Review – Gimmick or next generation computer control device?

Ever wanted to be Tom Cruise on Minority Report? I don’t mean jumping off high buildings or getting the best girls – I am referring to being able to control a computer in thin air using your hands! Well now you can (get closer to that possibility) thanks to Leap Motion.

Leap Motion is a controller that allows you to control your computer, (or more accurately provide another form of input) by waving your hands in the air and it will track not only your hand movement, but individual finger movements as well.

How does Leap Motion work?

Leap Motion senses how you move your hands in three dimensional space using two infra-red cameras and three infra-red LEDs. It allows you to point, reach and grab (picking something up etc) instead of clicks, taps, and drag-and-drops. Its tries to mimic how we interact with objects in real life.

Grab objects on screen as if you would in real life

The internals of the device contains two monochromatic IR cameras and three infra-red LEDs. The LEDs generate a 3D pattern of dots of IR light and the cameras capture almost 300 frames per second of reflected data. The data is sent to the computer where it is analysed by the Leap Motion controller software using proprietary algorithms not disclosed by the company. It works in a similar fashion to the Xbox Kinect which also calculates the 3D position data by comparing the 2D frames generated by the two cameras.

LEDs are positioned outer left, right and in the middle. The two “eyes” are the cameras
Leap Motion Accuracy

The first thing people usually think of when looking at Leap Motion Controller is Minority Report, the second is to draw parallels with Xbox Kinect. Remember the hype that generated when it first came out? Well a similar hype followed Leap Motion, and after the hype subsided a similar set of limitations were found.

The best app to test the device’s accuracy is the user training / Orientation app that comes for free. As you move you hand and fingers, you quickly realise couple of things:

  1. The area in which your hand is “seen” by the device is very limited, so you have to remember not to stray too far
  2. Fingers come and go! The app does a decent job of of capturing your fingers, but you have to really spread your fingers for it to pick them out otherwise it will get confused
  3. There is some lag between you moving and reflecting the movement on screen, its not a lot, but noticeable
My hand as seen by Leap Motion device

The best use for this device (as was the case for Xbox Kinect) is simple movements rather than delicate ones. Repeated and crude actions such as fist open / closed is easy to capture, but don’t expect it to allow you to play an air keyboard any time soon.


Leap Motion does NOT work for everyday applications, it does not work for Windows / iOS out of the box. It comes with its app store in the form of Airspace – its same idea as iTunes store but for Leap Motion apps instead. It is an ecosystem which allows you to hear about the latest and coolest apps designed specifically to work with the device. However, I found that the majority of apps did not have many user reviews, reflecting its small user base and also found downloading from airspace extremely download!

The apps themselves fall into various categories, but I was most interested in Education, Games and Productivity. The Educational apps include exploration themes like Google Earth and also science based apps to dissect a frog or a spider. The 3D aspects of these apps were quite good and enough to hold my attention for 10mins. However to control some of the finer movements requires a lot of patience, so I think this isn’t kids friendly enough.

Productivity apps include creative design apps and also apps to help you control your PC / Mac. In fact, given the amount of gesture controls built into the Mac, it is no surprise that the vast majority of Leap Motion OS control apps are aimed soled at the Mac. In fact, BetterTouchTool which allows users to gesture control their Mac is the top rated app in Airspace. The Windows offerings were slim pickings and in reality very limited by small set of gestures windows recognises.

I tried out two of the best games available, DropChord and Blue Estate Prologue. The latter is a shoot them up style game where you are running round holding your hand in the shape of a gun and aiming at Mafia type figures. There is an action to reload the gun, but otherwise the controls are pretty basic. The game itself is actually great fun and visuals / music amazing. However, after initial 10 seconds I couldn’t help thinking the game would be so much better if I could just use my mouse instead.

Blue Estate Prologue
Blue Estate Prologue

DropChord on the other hand was a game that truly works best using Leap Motion. It is a fast paced yet simple game which moves along with the beat of the music – reminds me a little of AudioSurf. This game really tests your ability to control your hands and after 10mins feels like you’ve been to the gym.

Leap Motion Causes Arm Fatigue

In the end, the biggest issue I have with Leap Motion device is fatigue. What Tom Cruise didn’t tell us was that it is extremely tiring keeping your arms up in the air all the time! Even with optimal position by resting your elbows, your arms feel like they are having a workout. After 20 years of using keyboard and mouse, I guess my arms are just not accustomed to all that effort required just to scroll the page or shoot a gun or dissect a spider.


Fun while it lasted, but for now just another gimmick – albeit one with a lot of backing and potential. I am going to keep mine for now, if for no other reason than to try out their impressive looking V2 software upgrade (due later this year) which should address all the issues I had with accuracy. However, I highly doubt they can make my hands any less tired.

Google Chromecast

Google Chromecast is a small, well priced and sexy looking piece of kit. It promises hassle free plug and play streaming functionality to your living room TV from a variety of devices such as PC, Tablet and Mobile – lets see if it can compete in this crowded market.

Chromecast unboxing
Chromecast unboxing
What is Chromecast used for?

As described by Google, “Chromecast is a thumb-sized media streaming device that plugs into the HDMI port on your TV“. It leverages your smart phone, tablet or PC to send your favourite shows, movies and music to your TV so you can watch online shows on the big screen rather than the tiny mobile screen. At the time of writing, various online channels such as Youtube, Netflix, BBC, BT Sport and Plex are all supported – but Amazon Prime, 4oD, ITV and Now TV are not yet supported.

How does Chromecast work

Why are some channels supported and others not I hear you ask. Well it is all to do with how this clever little device works. One could be forgiven by looking at the Google adverts that its the mobile or tablet device which streams the contents to the TV using wifi. Actually its much more clever than that.

When you select which clip(s) you wish to watch on your mobile phone, it will send the source of the clip to Chromecast. The Chromecast device will then stream the clip directly from the internet to your TV. The mobile / tablet becomes nothing more than a really fancy TV remote at this stage, allowing you to fast forward etc as if you would using the mouse on your computer. However this clever bit requires the individual channels to support the Chromecast APIs which most are now slowing onboarding but some are still holding out.

Clip from youtube streaming on the TV via Chromecast
Clip from youtube streaming on the TV via Chromecast
Chromecast remote control app as shown on my Android Phone - the picture is static on your phone, its just a nice background while your clip plays on the TV
Chromecast remote control app as shown on my Android Phone – the picture is static on your phone, its just a nice background while your clip plays on the TV

The other really feature of Chromecast is its ability to allow you to “cast” any Chrome tabs from your computer directly to the TV. This is a great workaround for certain channels which doesn’t have direct Chromecast support. However, streaming from Chrome browser only works for Chrome on your desktop PC and NOT from your mobile and tablet. There has been some work to improve this but at time of writing this does not yet work well.

My personal favourite use of Chromecast is to pair it with my PLEX server and use it to stream my collection of movies and TV shows which reside on my computer. Its so successful that I am going to have to find another use for my Raspberry Pi which was acting as the Plex client.

Aesthetics and Build Quality

As I mentioned earlier, Chromecast is a sexy little device – at least in the photos. However if like me you dont have a USB connection on your TV, then you end up with wire hanging out to the power socket which makes a mess of the simple look and feel. Although I cant really blame Google for this one, just myself for having an old TV :)

However, I do worry about the life span of this device, it runs super hot all the time, even when idle it is still hot to touch. I also wonder how much electricity it is burning up as I plug it direct into the socket it doesnt go off when the TV is on standby.


Google Chromecast is a wonderful little device, I believe its ever growing arsenal of channels and content will make it unbeatable at its £30 price point. Add full support for Chrome Android browser tab casting and it will help Chrome cement its place as the browser of choice too.

Do you have Chromecast? If so, would love to hear what you think in the comments below.

London Technology Week 2014

This week I was lucky enough to be able to take some time off work and attend the London Technology Week. This is a brief write up of the talks I attended and photos of some cool exhibits. Lets start with the talks

When smart-phones sense how you feel: The era of intelligent mobile devices

Talk description: “Argus Labs uses deep learning algorithms to sense, understand and predict human behaviour and emotions, based on the sensors in a smart-phone and general usage of a smart-phone. The presentation will demonstrate how smart-phones will start to behave as intelligent entities that know how a user feels and improve our lives.”

  • Argus Labs is working on APIs and SDK which will allow programmers to build emotion aware mobile apps
  • A variety of tools is used to predict mood, based on learning over time – i.e. every Monday morning you feel depressed and you tell the app this is how your feeling and over time it will form that pattern or maybe after everySaturday night after you come out of a club you feel happy. They also make use of the gyroscope to determine how happy / angry you are – for example, you are happy after clubbing and reading a book, but you might be jumping around after clubbing whereas your quietly happy after reading
  • The Presenter mentioned how personality is now really easy to predict – i.e. based on what feeds we subscribe to and what circle of friends we have. However mood is still extremely hard
  • An interesting topic was whether you should act on the user’s current mood or their predicted mood – i.e. if you know someone will be unhappy in an hour’s time, maybe play some happy music now to start counteracting that
  • A good example of this application is if the apps sees the user stuck in traffic and knows the user is typically angry – time to play some gentle music to help calm the user
Will cars be able to detect your mood in the future to make you a better driver?
Will cars be able to detect your mood in the future to make you a better driver?
  • The apps you build will learn about an individual’s mood and behavior over time, but is locked to that person so you cant pass your mobile to another user and expect it to work
  • Future of mobile is not about mobility, its been done – it will be about AI

This was a really interesting talk, made appreciate a lot more about how much companies are able to learn about me from my general online profile and keeping track of the places I visit etc. I start to think that one day my phone will know me better as a person than I do! Also the general idea of data mining and building a reasoning engine behind the massive amounts of data you collect is a theme that runs through many growth areas.

The Database of You – The opportunities and issues that arise from wearable technology everywhere

Talk description: “The last 5 years have seen an explosion in the growth of wearable technology, health and fitness data and mobiles apps and devices. Yet we are still only at the very start of our journey towards the database of me; – a personal cloud containing details of every aspect of our lives. How will the availability of huge quantities of health and performance data on everyone affect how companies do business, how people lead their lives and the general wellness of the population?”

  • Talk was delivered by CIO of Virgin Active Health Clubs and he started by mentioning that attrition rate in health club industry is a massive 60% – i.e. 60% of their members leave every year
  • The way to reduce attrition is to better facilitate users with their goals and allow users to see that they are making progress
  • The presenter mentioned the term “Cambrian explosion”, this is the period when there was a massive explosion of different life forms on earth and before settling on the best design – he sees wearable technology currently going through this period and everything we have not yet seen anything like the final design yet. He compared this to initial stages of the mobile where they came in all different shapes and sizes before everyone making phones that look like an iPhone
Graph showing popularity of a new technology as it comes out and then over time as it matures
Graph showing popularity of a new technology as it comes out and then over time as it matures
  • In terms of collecting data about individuals, he was nervous about how much personal data we are now able collect, but at the same time he felt everyone was starting to feel at ease with their data being in the cloud
  • This is an area which Apple, Samsung and Google are now all heavily investing with different platforms
  • Finally he compared current wearable tech to the early stages of car GPS systems which would plot on the map exactly where you are and the route you took – which was amazing when it first came out – to current GPS systems which also tell you about traffic and weather and best route home. So to make the tech actually useful you need a lot more context and a collective database about the person – The database of you.

Personally I really love the design of the new Samsung Gear – although I do worry slightly about the massive database of myself being held online, does that mean my medical insurance will go up with every McDonalds meal I eat? Maybe it should – but maybe this is just the perfect reason I needed to keep myself healthy as well.

Make sense of your (big) data and analyze in real-time like you have never done before!
Talk description: “With companies like Bloomberg, Facebook, Goldman Sachs and The Guardian using Elasticsearch, discover how the power of search can power your data analysis. We’ll enlighten you with some impressive use-cases for on-the-fly real-time data analysis and share dashboards that will delight you (and your stakeholders) beyond belief.”
Free Elasticsearch USB stick - yup I am easily brought
Free Elasticsearch USB stick – yup I am easily brought
  • Elasticsearch actually mentioned Goldman a few times as one of their star clients
  • Major advantage is its server plug and play capability – by adding new servers, the load will be automatically distributed for you
  • One of the most useful way to use it is not to look for the items with the biggest volumn / ticks / treads, but to look for exceptions in your data – i.e. comparing this week’s and last week’s dataset and seeing which currency is doing more or less relative to last week
  • Everything is open source and available for commercial use for free – Elasticsearch themselves make money by providing training and some APIs and tools
  • Do not use Elasticsearch db as your golden source if the data is important for you, always keep a separate copy and elasticsearch can lose data in certain edge case scenarios
Other cool London Technology Week exhibits

LiteCoin Mining (another BitCoin) with Nvidia GPU

The rise of BitCoin (BTC) has been front page news for the past year or so and unless you just emerged from the Jungle you will have followed its ups and downs. Unfortunately BTC is now too difficult to mine for your average build and require very specialised rigs to even break even. Looking around for the next best thing, I decided to give LiteCoin mining a try – at time of writing the second largest crypto currency by capitalisation.

Quick Summary
  • Mining is extremely addictive, but do it for fun and not for profit as most crypto currencies are now no longer profitable to mine
  • Mining can be done from any hardware / CPU, but it only really makes sense to do it from a GPU (Graphics card) on a desktop or dedicated rig – laptops will burn out and CPUs are too slow
  • Join a pool if you want to mine, WeMineLTC.com is the largest LiteCoin pool
Getting Started – Litecoin basics

Before you do start mining, you should get yourself a Wallet – this is where your coins will be held. There are online options and offline versions which you just hold on your PC. Given the number of virtual hack attacks against Bitcoin site, I decided to hold mine offline. The first time you run the wallet it will need to do a long sync as shown below – go watch a watch.

LiteCoin Wallet
LiteCoin Wallet

There are a variety of different ways to get started with mining if you haven’t done so before, I wont go into details here – you can find step by step guides towards the bottom of this blog in the references section. I just used my personal PC for this little adventure, i.e. no custom brought GPUs etc.

  • CUDA Miner (This is currently the only sensible choice for Nvidia GPUs, everything else is too slow for Nvidia)
  • Joined WeMineLTC.com (The largest LiteCoin mining pool)
  • Used GPU-Z to monitor my GPU temperature
CUDA Miner in action
CUDA Miner in action
Why mine LiteCoin as opposed to Bitcoin?

One reason why people have started to move away from Bitcoin is because it uses the SHA-256 hashing algorithm. This involves calculations that can be greatly accelerated in parallel processing. It is this characteristic that has given rise to the intense race in ASIC technology, and has caused an exponential increase in bitcoin’s difficulty level.

Litecoin, however, uses the scrypt algorithm which incorporates the SHA-256 algorithm, but its calculations are much more serialised than those of SHA-256 in bitcoin. Scrypt favours large amounts of high-speed RAM, rather than raw processing power alone.

The consequences of using scrypt mean that there has not been as much of an ‘arms race’ in litecoin (and other scrypt currencies), because there is (so far) no ASIC technology available for this algorithm. However, this will eventually change and we will be back to ASIC units for LiteCoin mining.

Buying and Selling Litecoins

While buying and selling (and spending!) of bitcoins is now fairly common place, adoption of Litecoins is still light. While USD and EUR to LiteCoin conversion is fairly common, GBP is more difficult. The best site I found was Bittylicious, its interface is simple and offers a large number of ways to pay.

Spending Litecoins I found challenging as most retail sites only accept Bitcoins, the only places which accept Litecoin as payment currently seems to be Crypto currency related website.

Hardware considerations

For general gaming, I would argue that Nvidia GPUs has always had the slighly edge over AMD/ATI. However for mining, historically AMD/ATI has beaten Nvidia hands down to such a degree that it has not been worthwhile to mine with Nvidia until recently.

While mining is fun, its important to not get too excited and end up overheating your GPU. Remember at the end of the day, unless you have a custom rig, chances are your GPU wont have enough fan power for you to over clock it and use it to mine 24/7. I strongly recommend you always use a GPU monitoring tool whenever you are mining with GPUs. I use GPU-Z as shown below.

TechPowerUp GPU-Z monitoring GPU load
TechPowerUp GPU-Z monitoring GPU load
Hire a miner / Rent a rig!

One of the most interesting developments in the mining world is the growth in the rent a rig or hire a miner business. Simply put, this is someone who has a lot more hashing power than you and you pay them to mine for you for a period of time.

You will find contracts for hire everywhere from ebay to special mining brokerages such my personal favourite Betarigs. This is also known as cloud mining, i.e. similar to cloud storage. Now you might wonder why someone would offer their hashing power to make a profit for you, the answer is they arent. You always pay more to rent the rig than what the rig will ultimately mine for you! Sounds silly at first, but then you are also paying for electricity and hardware if you were to do it on your own so maybe not so different after all.

Why Mining is unprofitable for your average enthusiast

I started this blog by saying how addictive mining is but also that it wasn’t profitable for your average enthusiast. I will finish by mentioning some of the hidden costs involved and why if you only want to speculate on the future value of BTC / LTC, you should just buy the currencies rather than mining them yourself.

The biggest obviously cost most people will have to spend to have any chance at mining profitability is to buy the latest and most expensive gear. This could be thousands of pounds equipment and cost of which will take you many months to simply recuperate.

The other big killer is electricity – yes that hidden cost which you may not care about when running your average PC, which when you have a custom mining rig, this is one of your biggest costs. This has become such an important area due to rising electricity prices that Nvidia has recently brought out new cards which aim to half the running voltage and this is expected to be a killer features in its race with AMD/ATI.

Even with the fact that mining isn’t profitable, I still absolutely love it. Also don’t say I didn’t warn you, it is amazingly addictive, what are you waiting for? START TODAY!


Raspberry Pi Media Center

There is currently a wave of new TV streaming solutions fighting it out for our hard earned money such as Chromecast from Google, Fire TV from Amazon, Apple TV, Roku etc. In fact, they are all very good in their own right. For example, if your household is full of Apple products, you wont go wrong with the Apple TV. If cost is a factor, then Google Chromecast is an absolute bargain for what if gives you. Today we explore some open source approaches to this problem, using a Raspberry Pi Media Center.

Raspberry Pi Media Center – What are the options?

Now I am sure there are many more options out there, but these seem to be the most popular and by nature the ones you will get the most support for (all solutions discussed here are essentially a variant of XBMC)

  • Raspbmc (runs full Linux under hood, slow)
  • OpenELEC (bare bones, fast)
  • Rasplex (on top of OpenELEC)
  • XBian (on top of Raspbian)

There is a very good article which goes into the pros and cons of each of these here – http://lifehacker.com/raspberry-pi-xbmc-solutions-compared-raspbmc-vs-openel-1394239600. What I will concentrate on is my experience with Raspbmc and Rasplex.

Raspberry Pi Media Center using Raspbmc

My first attempt was to use Raspbmc as it seems to have a very large community which offered a lot in the way of plugins. The installation process was extremely simple, with the Raspbmc installer doing all the work and you just have to supply the SD card. Once the SD is setup on your computer, plug it into your Raspberry Pi and let it boot up the first time (it takes a long time first time round).

Raspbmc starting up first time

I started out using a spare SD card I had from my camera, this was a big mistake as it was only class 4 (i.e. slow). This and the fact that Raspbmc itself is also known to be slow, meant I had a slightly sluggish experience with all the menus and overall experience wasnt great.

In terms of look and feel, it looks exactly like the full XBMC client for Windows. You can use the keyboard or mouse for navigation, with an intuitive menu control system.  The plugins (video channels) were also very easy to install and Raspbmc comes with a very large selection of recommended ones, but there are hundreds if not thousands more out there on the net you can add yourself. Below is the YouTube channel post installation.

Raspbmc youtube plugin screen

Unfortunately where Raspbmc fell short for me was in its ability to stream videos from my home computer. Now you might not have any movies stored locally and watch everything from Netflix, in which case this issue wont affect you. So lets start with a clarification, Raspbmc is able to access my home computer and movie files, but it takes a lot of effort. Firstly you have to setup folder shares on your local computer and then configure Raspbmc with the right access details to see those files. Additionally, I started reading that it might not support all codecs out of the box, this was a big issue for me given I have movies with codecs of every sort and had no desire to recode any of them.

Raspberry Pi Media Center using Resplex

After the disappointment of Raspbmc, I decided to try Rasplex. Its main selling point is that it will do video streaming automatically. Now I wanted to be fair, so I installed it on the same class 4 SD card from earlier (by this point I had purchased a much faster class 10). The speed was now acceptable, no more lags!

The Rasplex menu system was in many ways even more beautiful than Rasbpmc, it cycles its background image to that of various shows related to your current menu selection. However, the menus needs a few more clicks before offering you the same content as Raspbmc.

Rasplex main menu system

The only downside and this is quite a big one for me is the lack of mouse support – yes, Rasplex is keyboard only as far as I could work out. While I don’t mind having to purchase a wireless keyboard, it just doesn’t work very well when you are fast forwarding a movie. You can download various apps for your phone, but they are similarly poor in this regard as fundamentally they do nothing more than map onto keyboard keys. If anyone knows differently and can get the mouse to work, please let me know!!

Now let me come to Rasplex’s (and indeed PLEX’s – the media server on your computer or NAS) strongest selling point. It does video streaming better than anyone else. Install PLEX on your local network computer or NAS and Rasplex will automatically find it and sync all your TV shows and Movies. The only thing you need to do is to restrict your PLEX server to look in specific folders on your computer if you don’t want to share everything – i.e. your family videos. Everything else is done for you including syncing any future new movies or TV shows you add – it took me all of 5mins to get my TV and Movie collection shared to my TV.

Rasplex main menu movies section

If you signup for an account with PLEX, you can even stream your content remotely to any device over the internet. I downloaded the Android client (this costs a small fee) but have yet to test out the performance. PLEX apparently will look at your connection and device screen size before streaming the video in the appropriate quality for your device. You shouldnt even have to worry about codec either – although some will have better performance as PLEX doesn’t have to worry about recoding on the fly.


Lets quickly summarise the main pros and cons I encountered with each Raspbery pi media center solutions

  1. Raspbmc: Great for out of the box support for plugins, but slow
  2. Rasplex: Unbeatable streaming solution, but no mouse support

If you dont care about streaming your own content, I would give Xbian or OpenELEC a try as they should be similar to Raspbmc but faster. If you primarily want to stream stuff from your computer to the TV, go with Rasplex.

Have you tried any other solutions or just want to share your own experiences with Raspbmc or Rasplex? Please leave your comments below.