N95 camera distortion part 2
Could be wrong.
Actually what caused my presumed mistake was this research on the Nokia N95 camera calibration
N95 Distortion Evaluation
They got huge distortion estimation – like 3% of the screen width. I don’t detect anything like this in the 320×240 viewfinder. My upper bound is like .7% (though I didn’t do complete calibration, just did some rectangles shots).
N95 camera distortion ?
I’m making full screen version of my AR Tower Defense game, and stumble at some strange problem. It seems to me the camera distortion is absent if I’m getting scaled down viewfinder image (or may be it’s just cropped). If I’m getting full viewfinder image it looks like some camera distortion creep in – seems markers getting distorted. I may have to calibrate camera, and that would create portability problem. The game will work only for N95 camera…
Marker-based AR application and games could be viable.
Blair MacIntyre written in his blog that he consider markers for AR to be a “prop”: “As soon as your start requiring props, that makes the games less portable … a conundrum to be sure.” Whoever it could be that marker-based AR games/app are not actually so bad.
Edge report that “79 percent [of those polled say] they use their portable device in-home, far more than any other location.”
The interesting thing that in-door marker-based tracking have no disadvantages comparing with markerless. Markers could be easily placed on any flat surface, or taped/pinned to vertical surface. Most of surfaces are at the right angles, so one can even make easy to track non-planar multimaker arrangement – like putting markers both on the table and the adjacent wall. In some cases, like on smooth uniform surfaces only marker-based tracker can actually work, markerless would just fail there. Of cause markereless tracking is more scientifically impressive and fun to develop, but marker-based works right now )))
From business point of view marker based apps and games can provide interesting opportunity – non-intrusive mobile advertising. Instead of pushing ad into the face of the user, on the screen, occupying precious screen real estate, ad or logo can be put on the marker itself. That way it remain both highly visible and non-annoying. Different ad bearing markers could be keyed to different content units, thus providing ads rotation.
Augmented Reality Tower Defense game is up for download
It’s here. In this demo I’ve used the same multimarker tracker I’ve used in last demos. 3d position of the camera calculated form markers used for placing tower. Third dimension used to control tower height
If you don’t know what Tower Defense is, here is wiki entry
Nintendo DSi and Augmented Reality
It seems Nintendo DSi could be a good platform for AR. It already include video-processing AR-like tools, which have color or texture segmentation and some feature detection, though feature detection doesn’t seem especially stable, as could be seen on this video.
Most interesting thing though is DSi new CPU. bunniestudios.com report: “I can tell the CPU is substantially beefed up (consistent with reports of the DSi battery life being shorter than the DS-lite, despite having similar battery capacities…)” If DSi really have around 300Mhz CPU you can expect about the same performance as Nokia N95 for image registration. So my AR demos would have little quality loss for DSi comparing with N95. Lack of 3d accelerator for DSi would hurt of cause.
Phone camera as 3d pointing device
Here is a short video how phone camera could be used as precise enough 3d pointer.
This demo use the same engine as my first demo.
A new demo in the work
This one would be less about usage real-world objects, more about phone camera as 3d mouse.
Version 0.02 of the demo is up
At my homepage
New
1. Objects scanning improved
2. The manual improved and extended.
3. Some bug fixes and rebalances.
4. Some game environment changes.
5. support for E51 and hopefully for E50
Mirror Image 