Monday, November 30, 2009

Augmented Reality Resources for Software and Hardware

One aspect of AR DevCamp is building and hacking stuff.  Augmented Reality has been around for quite some time and there are many software projects and some hardware projects.  I'll  cover what I found after a couple of days of searching.  This isn't intended as a comprehensive list, rather its a sampler of what's available right now.

Marker based Augmented Reality
Augmented Reality has been around for some time; but until the relatively recent advent of smart phones with compasses and GPS, the major focus of open source AR software has been around markers that register images superimposed on the a camera view.  The canonical implementation is ARToolKit from Washington University which has spawned implementations in multiple programming languages. In addition to ARToolKit derivatives, other marker based AR software are Goblin and Goblin XNA which was developed using C# and .NET, Simplified Spatial Target Tracker (SSTT) Visualizer developed by Hartmut Seichter in C++, and Studierstube Tracker which is conceptually similar to ARToolKit but is a different code base designed for mobile phones. Here is the sampler list for Augmented Reality marker software.


C family:

Mobile Augmented Reality
Mobile Augmented Reality places information, markers, and 3d objects in the camera view of a mobile device based upon location derived from GPS or positioning information and direction, typically from compass and accelerometer.  Markers are typically not used in mobile augmented reality platforms such as the iPhone or Android based phones.

Android and iPhone:

Augmented Reality hardware projects abound ranging from hacking heads-up displays (HUD) to wearable computing.  Pranav Mistry recently announced that the sixthsense project will be open sourced, probably so we won't have to resort to this:

There are also a lot of cool human computer interaction (HCI) projects coming from assistive technology that can be used to expand the AR experience.  Alternative modes interaction include using eye tracking for input and sound to provide additional cues that improve the user experience.  Also listed are a couple just plain cool projects

User Input:
Cool Stuff:
This just scratches the surface of AR apps. Mashups between other software and public Augmented Reality APIs, such as Wikitude, are just starting.

Monday, November 23, 2009

AR DevCamp NYC

Augmented Reality Dev Camp (the unconference formerly known as GeoAR Camp) is scheduled for December 5th in Mountain View, CA.   AR DevCamp 1.0 is a full day of technical sessions and hacking opportunities in an open format, unconference style.

While a weekend jaunt to Mountain View from the east coast is well within the realm of possibility, the idea of yet another red-eye after a full day of unconference sessions and post event socializing sounded exhausting.  Tish Shute of  Ugo Trade and I were commiserating about not attending AR DevCamp, so we decided host a simultaneous AR DevCamp in New York for people on the east coast that couldn't make it to Mountain View.

New York has quite an active AR community, so there should a be diverse crowd that approaches AR from many different perspectives.  So far, some of the suggested topics are the Outernet Guidelines Initiative, using PyGoWave to implement the Google Wave Protocol for AR , the Internet of Things, and many more.  Like Mountain View, this an open format unconference. We plan to make use of teleconferencing and Skype to share sessions and include people who can not attend physically.  

The details are below and I hope to see geo-folks in attendance. 

New York City Event

ARDev Camp NYC is an open format unconference for Augmented Reality technical discussions and hacking opportunities. It will overlap with ARDev Camp in Mountain View, CA and provide an opportunity to collaborate with Mountain View.

Who Should Attend:
Anyone interested in mobile Augmented Reality, 3D graphics, the geospatial web, Outernet Guidelines, applications of AR in advertising and film industry (adult or otherwise), AR+Semweb, Google Wave Protocol for AR, locational privacy

December 5th, 2009. 10:00AM-9:00PM

The Open Planning Project office (TOPP) Penthouse in Manhattan

ARDev Camp NYC will take place at TOPP/OpenGeo's offices at 148 Lafayette Street, one block east of Broadway and one block north of Canal in downtown Manhattan. The nearest subway lines are the 6, N, Q, R, W, J, M, and Z.

Community Info:
Twitter: @ardevcampnyc, #arnyc
Skype: ardevcampnyc

We are looking for sponsors for meals,snacks, and drinks; if interested please contact

If you're interested in attending or leading a session, sign up at ARDev Camp NYC on the ARDev Camp Wiki

Monday, November 9, 2009

Dell Mini 9 OSX: Blue screen after an update

I received an update notice from Apple for Java, Quicktime, and of course 10.5.8. Unchecking the 10.5.8 option, I accepted the update; but I forgot about it and didn't reboot for a couple of weeks.  I shut down the Dell Mini the night before a trip and when I got to the airport (free wifi at SAT), I booted up and it hung with a blue screen.  I was able to start the machine in Safe Mode during the DellEFI1.2a5 boot sequence by typing -x.  I fiddled with the DellEFI1.2a5 options, but none of that fixed the problem.

I had some time to think about it during my flight; something had gone wrong with the update and I decided to update the system to 10.5.8 as soon as I had internet access.  I chose to use the combo update because I like hit things with the biggest hammer I can find. The 10.5.8 combo update is huge, ~780 mb, and I think that safe mode also limits the download speed of the wifi card because the download rarely went above 125 kbps.  Another interesting side effect of Safe Mode is that the ethernet jack was working but could not recognize that the cable was plugged in.  After waiting a couple of hours to download the update, I ran it, which took another hour.  I did the DellEFI1.2a5 dance of removing the dsdt.aml file, rebooting to Safe Mode, running DellEFI1.2a5 to create a new dsdt.aml and reload the extensions, the rebooted with anticipation. After all of that, I still had a blue screen.

I tried a bunch of things such as checking the disk, removing programs from start up, but none of it worked.  Out of desperation, I decided to try the OSX Startup keystrokes, starting with booting to Safe Mode by holding the Shift key down during the the OSX boot sequence (Darwin is loaded and the Apple boot screen is displayed), and not using the DeLLEFI1.2a5 method.  It worked (but not as intended)!  The machine booted normally instead of going into Safe Mode; the first boot took a little longer than normal but subsequent reboots took the usual less than 20 seconds.

My initial hunch was correct, but rerunning updates did not work, so I did a little more research on why it worked. It turns out that holding the Shift key during boot does the following on OSX 10.5.6 and higher:
A Safe Boot deletes the dynamic loader shared cache at (/var/db/dyld/). A cache with issues may cause a blue screen on startup, particularly after a Software Update. Restarting normally recreates this cache.
While holding Shift during boot did not send the Dell Mini into safe mode as it would a regular Mac, it did delete the dynamic shared loader cache.  Of course, you can delete the cache manually while in Safe Mode.  Hope some one finds this arcane piece of knowledge useful.