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How difficult would be to fly one hd filming plane above, then scour the imagery with a fine comb, possibly computer vision aided?

by pacala 7y ago

wil421 7y ago
You would need different angles especially if there was tree cover or mountainous terrain.
thaumaturgy 7y ago
Very. A similar tactic was used when Steve Fossett disappeared (https://en.wikipedia.org/wiki/Steve_Fossett#Disappearance_and_search https://en.wikipedia.org/wiki/Steve_Fossett#Disappearance_an...), and it was entirely unsuccessful. There are a few challenges: 1. There is a direct relationship between the time and effort required to take imagery, and the image resolution. Which is to say, if you want imagery that's detailed enough that you can find likely evidence without a lot of false positives, then you have to spend a ton of time in the air at low altitude, and if you want to effectively search a large area, then you have to spend time at higher altitude where you're too high up to get useful imagery. 2. Humans aren't good at sorting out natural features from unnatural ones. My favorite example of this is the face on Mars. Same deal when trying to search through imagery for debris. People have a preconception of what a plane crash looks like, and it's usually wrong. They'll confuse light-colored rocks, trees broken by snow loading, and all kinds of other things for evidence, while completely missing actual evidence. So the problem with these systems for search managers is that once someone flags something in a picture, you're kinda obligated to check on it, which takes resources away from more likely search areas. 3. The technology isn't there (yet). Computer vision may get better than humans at this soon, but not yet, and certainly not in the kind of technology that even well-funded search organizations or adventurers has access to. NSA? Maybe. Us? Nah, best we get is grainy photographs of features 1m across from high up. IR imagery currently has similar problems, there's just too much background noise in most cases. Some kind of multi-spectrum imagery fed into a big convolutional NN might be able to do a better job of telling the difference between a rock and some twisted metal and plastic composites at 1m resolution, but I don't know if anybody's actually invented that yet. I'm using 1m resolution here as a substitute value for whatever would be appropriate to cover a large area with reasonable resources. After the Camp Fire, Alameda County brought a really cool tech team out that covered large areas of the burn with imagery from drones. They got a 1cm aerial resolution that was good enough to satisfy insurance investigators. But, it required a lot of flight time and computing power to do that, and they covered a relatively small area compared to the search area for a missing aircraft.
deleted 7y ago
[deleted]
mopsi 7y ago
Sometimes there are no traces left behind. In 1947, Avro Lancastrian airliner flew into a mountain in the Andes and triggered an avalanche that buried the wreck. Compressed snow slowly turned into ice and became a part of the glacier. Over the next 50 years, the wreck moved down the mountain with ice until it eventually melted and revealed parts of the aircraft. They were found by two mountaineers in 1998. https://en.wikipedia.org/wiki/1947_BSAA_Avro_Lancastrian_Star_Dust_accident https://en.wikipedia.org/wiki/1947_BSAA_Avro_Lancastrian_Sta... If an aircraft goes missing, we're usually dealing with mountains, oceans or remote areas with dense tree covers. Remote sensing is very limited in these environments.

How difficult would be to fly one hd filming plane above, then scour the imagery with a fine comb, possibly computer vision aided?

by pacala 7y ago

How difficult would be to fly one hd filming plane above, then scour the imagery with a fine comb, possibly computer vision aided?

wil421 7y ago

You would need different angles especially if there was tree cover or mountainous terrain.

thaumaturgy 7y ago

Very. A similar tactic was used when Steve Fossett disappeared (https://en.wikipedia.org/wiki/Steve_Fossett#Disappearance_and_search https://en.wikipedia.org/wiki/Steve_Fossett#Disappearance_an...), and it was entirely unsuccessful. There are a few challenges: 1. There is a direct relationship between the time and effort required to take imagery, and the image resolution. Which is to say, if you want imagery that's detailed enough that you can find likely evidence without a lot of false positives, then you have to spend a ton of time in the air at low altitude, and if you want to effectively search a large area, then you have to spend time at higher altitude where you're too high up to get useful imagery. 2. Humans aren't good at sorting out natural features from unnatural ones. My favorite example of this is the face on Mars. Same deal when trying to search through imagery for debris. People have a preconception of what a plane crash looks like, and it's usually wrong. They'll confuse light-colored rocks, trees broken by snow loading, and all kinds of other things for evidence, while completely missing actual evidence. So the problem with these systems for search managers is that once someone flags something in a picture, you're kinda obligated to check on it, which takes resources away from more likely search areas. 3. The technology isn't there (yet). Computer vision may get better than humans at this soon, but not yet, and certainly not in the kind of technology that even well-funded search organizations or adventurers has access to. NSA? Maybe. Us? Nah, best we get is grainy photographs of features 1m across from high up. IR imagery currently has similar problems, there's just too much background noise in most cases. Some kind of multi-spectrum imagery fed into a big convolutional NN might be able to do a better job of telling the difference between a rock and some twisted metal and plastic composites at 1m resolution, but I don't know if anybody's actually invented that yet. I'm using 1m resolution here as a substitute value for whatever would be appropriate to cover a large area with reasonable resources. After the Camp Fire, Alameda County brought a really cool tech team out that covered large areas of the burn with imagery from drones. They got a 1cm aerial resolution that was good enough to satisfy insurance investigators. But, it required a lot of flight time and computing power to do that, and they covered a relatively small area compared to the search area for a missing aircraft.

deleted 7y ago

[deleted]

mopsi 7y ago

Sometimes there are no traces left behind. In 1947, Avro Lancastrian airliner flew into a mountain in the Andes and triggered an avalanche that buried the wreck. Compressed snow slowly turned into ice and became a part of the glacier. Over the next 50 years, the wreck moved down the mountain with ice until it eventually melted and revealed parts of the aircraft. They were found by two mountaineers in 1998. https://en.wikipedia.org/wiki/1947_BSAA_Avro_Lancastrian_Star_Dust_accident https://en.wikipedia.org/wiki/1947_BSAA_Avro_Lancastrian_Sta... If an aircraft goes missing, we're usually dealing with mountains, oceans or remote areas with dense tree covers. Remote sensing is very limited in these environments.