Drone 3D Survey

I always want­ed to do this, a 3D drone survey.

I took pho­tographs from my drone in var­i­ous grid pat­terns. These pho­tographs were then processed using Open­DroneMap. The process took a lot of com­put­ing pow­er, with some tak­ing 48 hours on a 24-core processor.

Mea­sure­ments can be tak­en for heights, widths, dis­tances and vol­ume accu­rate to around an inch.

You can view it online here:

Use your mouse to spin it around.

Designing Voice User Interfaces

Designing Voice User Interfaces

I watched this refresh­ing video on improv­ing Voice User Inter­faces. I can see how it could be used to improve many tele­phone menus I’ve used.

How to watch the NTU Falcon Cam on PC, Mac, iOS and Android (Updated 2019)

How to watch the NTU Falcon Cam on PC, Mac, iOS and Android (Updated 2019)

I’ve noticed many peo­ple hav­ing prob­lems watch­ing the cam­eras, as the offi­cial web site still uses the now defunct Flash, so I wrote this short guide on a way to play the live stream from the cameras:

For PC and Mac

  1. Down­load and install VLC Play­er
  2. Down­load this file (right click and Save As): https://www.jonhassall.com/downloads/ntufalconcams.m3u
  3. Open VLC Play­er, Media -> Open File, and open the file you downloaded
  4. Press the track skip but­tons to change cameras

For Android smartphone

  1. Install the VLC Play­er app from Google Play
  2. Open the VLC Play­er app
  3. Press ‘Open MRL’ from the left menu, and type:
  4. I find it can take a good 30 sec­onds for the stream to open. Play con­trols appear if you swipe up from the bot­tom of the screen. It isn’t very intuitive


  1. Install the VLC for Mobile app from the App Store
  2. Open the VLC Play­er app
  3. Press ‘Net­work Stream’ from the left menu
  4. Type this URL into the box at the top:
  5. Press ‘Open Net­work Stream’
  6. Press ‘ntucalconcams.m3u’ which should now be added to the list
  7. The cam­era streams should now show. It can take 30 sec­onds to start. Use the track skip but­tons to change between the three cameras.

Hope­ful­ly in the future NTU will either stream direct­ly to a HTML5 com­pat­i­ble for­mat, or set up a live stream­ing con­ver­sion server.

Hope this helps peo­ple enjoy watch­ing the falcons.


Rock, Paper Scissors

Rock, Paper Scissors

I lis­tened to an inter­est­ing pod­cast today, explor­ing the game Rock, Paper, Scis­sors, pre­dic­tion pat­terns and game theory.

Being clever isn’t an effec­tive way of win­ning, as peo­ple are rarely per­fect deci­sion mak­ers. The Nash equi­lib­ri­um is only rel­e­vant to domains with per­fect deci­sion mak­ers. So it is impor­tant to con­sid­er the choic­es of others.

In the pod­cast, it was men­tioned that from large datasets:

The biggest chunk of peo­ple will think one step ahead, the next biggest chunk of peo­ple will think total­ly ran­dom­ly, the next biggest chunk of peo­ple will think two steps ahead, and a small num­ber of peo­ple will go beyond two steps.

It also con­sid­ers crowds and groups influ­enc­ing decisions.

Link to the pod­cast: Rock, Paper, Scis­sors (BBC) 

Rock, Paper, Scissors