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New Video Shows Shot Down Drone Hovered For Only 22 Seconds
AmiMoJo writes: The saga of the drone shot down in Kentucky got a little bit longer today. A new video from the drone shot down by William Merideth shows that it only hovered over his property for 22 seconds, and was not "peeping". The video shows the drone hovering at altitude and surveying the area before falling out of the sky. Although the video jumps around a little, the drone's owner claims that it was not edited. The shooter says he did not know if the drone was being operated by a paedophile, criminal or ISIS terrorist before he opened fire.
And, this wasn't the first flight in the area that is within view of the property. FTA:
During its first flight, the Phantom apparently gave an error message and could not fly past this road without a setting change. So, Boggs brought it home, fixed the settings and swapped its battery—giving time for Merideth to go inside, retrieve his shotgun and wait for the drone to return.
All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
As someone who delivers video systems and RF downlinks for drones and helicopters I see four kinds of artifacts in that video:
1) Yes, rolling shutter artifacts appear to be there, but they're very minor (i.e. distortion in the young man's face in the lower left of the first few frames). It appears that the camera is mounted on a gyro stabilized platform. Overall, I suspect that this may even be a full-frame chip, and what appear to be rolling shutter artifacts are actually due to the high compression. Rolling shutter artifacts are very, very annoying and not tolerated well by most users so rolling shutter video chips are going out of style.
2) Lost/corrupted packets. I'm guessing that this is a VOIP system using UDP packets, and you can see some glitches in rows of pixels, like at 0:13 above the horizon to the left. These are often accompanied by 3) and seem to be a predecessor of 4).
3) Compression artifacts. This is probably MPEG-4 of some kind, and you can see the bit rate is rather low because of the blockiness and persistence of bad blocks caused by lost/corrupted packets. The bit rate is low most likely because the RF link won't support a higher one...
4) Lost Link artifacts. These are the most obvious ones, and run from brief ones less than a frame long, which produce the top-down partial-screen "wipes" to ones that last several frames or even several seconds, which look like full-frame "wipe" edits. These are almost certainly caused by loss of radio link from the drone to the ground. The recording software isn't substituting blank pixels or frames, it's just picking up where it left off when it gets the video stream back. Aesthetically, it's probably the best way to go, but if you're collecting something you expect may need to be forensic evidence, it does inconveniently make the video look like it's been edited.
If I were called in to testify on this video clip, I'd say my opinion is that the wipes are caused solely by loss of link, but the video could have purposefully been edited to appear that way.
As for why it jumps so much? His RF Link sucks. Either he's not orienting his antennas correctly (calibrate your magnetometers if you're using gimbaled antennas! Your fixed omnis should stay vertical!) or he's using very high gain omnis at too short a range, or both. Higher gain omnis have deeper nulls at zenith and nadir. (It may seem tempting to the layman, but you don't point your ground station omni at the aircraft - if you're gonna actively aim the antenna, then it should stay perpendicular to your drone.) Finally, he's probably operating in the 2.5GHz ISM band, which in a suburban area like that is probably quite noisy with WiFi and microwave oven interference. Switch to a 5GHz system, it may still be noisy, but at least you don't have all that energy from a magnetron in every home and business spewing radiation intended for hot pockets, leftover mac and cheese, and that fish somebody brings every day for lunch.
I can see the fnords!
First flight mode, 100 feet restriction. Happens every time you update your firmware or you use a new device.