Disposable quadcopters could democratize aerial panoramas
High-quality aerial photos taken with sub-100g quadcopters and from cameras mustering less than a megapixel in resolution could make panoramic photography far more accessible, affordable, and flexible, one researcher has discovered. Whereas traditional approaches to aerial imagery have relied on heavy, high-resolution cameras which demand professional operation, Camille Goudeseune of the University of Illinois at Urbana-Champaign went to the other extreme, using near-disposable quadcopters that are effectively toys and software cleverness to stitch together multiple frames from cheap video cameras around 640 x 360 in resolution.
While an individual shot from such a camera might not be impressive seen in isolation, Goudeseune found that by combining several of the frames in post-processing can piece together a far more detailed image. Beneficial is the high potential framerate, which can reach around 60fps but still record up to an hour's flight on an 8GB memory card.
Toy quadcopters are surprisingly capable, the researcher points out, though their usefulness has been traditionally limited by their tiny payload. That has prevented even higher-resolution smartphone cameras from being sent skyward, but the "keychain camera" (aka an "808" by enthusiasts) weighs in at around 8g.
Goudeseune's system effectively extracts JPEGs from the Motion JPEG footage, strips out duplicates, and then passes them over to an image stitcher. The latter needs a little hand-holding, though, since it assumes a common viewpoint for each frame, rather than the perspective of a shifting aircraft; the best results come from "a single monotonic yaw maneuver" Goudeseune says.
Other processing techniques remove moiré, blocking, motion blur, artifacts, and other glitches, and the end result is a surprisingly high-quality panorama like the one below. Best of all, the researcher argues, just about anyone can get up and running with the minimum of practice, and even if the quadcopter crashes it's unlikely to injure anyone or be too expensive a blunder.
"Basic piloting skill is needed, but the more fundamental skill is choosing where to fly and when not to fly" Goudeseune concludes. "Even without these skills, though, loss of flight control presents a hazard hardly greater than that of a stray Frisbee. The same cannot be said of an aircraft powerful enough to carry a 100g camera."
