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High-Speed Video Using a Dense Camera Array
karvind writes "Researchers at Stanford have demonstrated multi-thousand frame-per-second (fps) video using a dense array of cheap 30fps CMOS image sensors. A benefit of using a camera array to capture high speed video is that we can scale to higher speeds by simply adding more cameras. Even at extremely high frame rates, our array architecture supports continuous streaming to disk from all of the cameras. Now we know where to use 100TB tape drives and what to expect in the next sci-fi movie."
This is a very interesting development. If you watch the movies (especially the movie with balloon popping, I think its the third movie), you will see that this is an extremely accurate capture of the event. I would be interested to see how this could present itself in a regular consumer atmosphere...multiple cameras would not exactly make the cut. But yes, it does give a good idea on how to use the 100TB tape drives
How do they put all the footage together in the correct 'order', that is to say where each frame is in sequence.
How can they be sure that none of the cameras capture the same instant of the action?
To be honest, for the examples given, the image quality is somewhat lacking.
I can imagine this working REALLY well for crash simulation studies where the subject is a greater distance from the camera array.
The baloon popping movie needs quite severe modification to the captured images, and doesn't do much justice.
The effect has already been used in bullet time type fx effects anyway, they used an array of cameras firing in a sequence whilst laid around a subject.
The effect with bullet time is a lot cleaner because the captured images are not expected to be spatially aligned, and instead are made to give the effect of moving the camera around a subject.
liqbase
T think "cheap 30fps CMOS image sensors" simply refer to webcams. From the quality i've seen, they might be in the order of 20$ per unit, which makes to whole camera array about 1000$. Also those webcams do not produce thousand of megabytes, even at rates of 1MB/min you can get decent quality, which makes the video stream to be about 50MB/min.
I don't think so.
The more I look at this, the more I think they are making life difficult for themselves, and the resultant image quality shows.
Since making my first postings on this discussion, I decided to have a look around at how the professionals handle high speed photography and came up with some nice results.
Theres a company called Photron that have a range of single digital cameras capable of megapixel images at 2000fps.
In their gallery, they even have an example of a water filled baloon popping, and tbh it looks a lot better than this multi camera version.
Agreed, this is a way to do it on the cheap, but because of the spatial issues and timing complexities, it may be more trouble than its worth, and may well be wise to buy a camera from the professionals.
liqbase