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How Google Earth Images Are Made
An anonymous reader writes "The Google Librarian Central site has up a piece by Mark Aubin, a Software Engineer who works on Google Earth. Aubin explains some of the process behind capturing satellite imagery for use with the product. 'Most people are surprised to learn that we have more than one source for our imagery. We collect it via airplane and satellite, but also just about any way you can imagine getting a camera above the Earth's surface: hot air balloons, model airplanes - even kites. The traditional aerial survey involves mounting a special gyroscopic, stabilized camera in the belly of an airplane and flying it at an elevation of between 15,000 feet and 30,000 feet, depending on the resolution of imagery you're interested in. As the plane takes a predefined route over the desired area, it forms a series of parallel lines with about 40 percent overlap between lines and 60 percent overlap in the direction of flight. This overlap of images is what provides us with enough detail to remove distortions caused by the varying shape of the Earth's surface.'
"Most people are surprised to learn that we have more than one source for our imagery." Must be people who never leave the US border? How can you possibly miss what a hodge-podge of a patchwork Google Earth is? It's especially apparent if you zoom in on a small island.
My bad.
I had a Keyhole subscription for years before Google bought it, and it was really cool. If all you've seen is the Javascript kludge, you haven't seen the real thing. The real Keyhole application required 3D hardware, could do smooth zooms, tilts, and pans, and showed the world with elevation.
Google still offers that as a download, but it's not used all that much.
From the sounds of it, I have a digital camera that does pretty much the same thing. You take 3 pictures with some overlap and it's able to stitch them together to make a panoramic shot. It displays part of the previous shot so that you can line up the shots properly for good results.
It's very easy to see that google gets the images from many sources, because often times you'll go over by 1 KM, and be left with a blurry mess whereas it was crystal clear before.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
If a google guy turns up asking to take photos of my neutrons he can kiss my shiney metal ass.
Task Mangler
Google Earth: From Space to Your Face...and Beyond
By Mark Aubin, Software Engineer, Google Earth
Would you believe the inspiration for Google Earth was a photo flipbook?
It was 1996 and I was working at Silicon Graphics (SGI), which was then on the verge of releasing "InfiniteReality" -- hardware for the Onyx workstation that enables people to create graphics with extraordinarily realistic texture. Our goal was to produce a killer demo to show off the new texturing capabilities to maximum advantage. During a brainstorming session, someone passed around the great Charles and Ray Eames book, POWERS OF TEN -- A Flipbook, and suggested that our demo move through imagery the way the book does. After discussing a number of possibilities, we decided that we would start in outer space with a view of the whole Earth, and then zoom in closer and closer.
We'd begin by heading toward Europe, and then, when Lake Geneva came into view, we'd zero in on the Matterhorn in the Swiss Alps. Dipping down lower and lower, we'd eventually arrive at a 3-D model of a Nintendo 64, since SGI designed the graphics chip it uses. Zooming through the Nintendo case, we'd come to rest at the chip with our logo on it. Then we'd zoom a little further and warp back into space until we were looking at the Earth again.
We called this demo "Space-to-Your-Face." And after showing it literally thousands of times to people all around the world, it's clear to me that we are universally fascinated with seeing our world from this perspective. During one school group demo, the teachers actually jumped up from their chairs and started pointing to places on the screen as we "flew" over the globe. They were ecstatic. The one comment we kept hearing: I've got to have this for my classroom!
Only a few years later, advances in computer and internet technology made it possible to deliver high-resolution imagery at sufficient speeds to enable a fluid flythrough on a standard PC anywhere in the world. So I decided to leave SGI and team up with a few others to found Keyhole, where we launched the first digital globe product to stream nearly unlimited, high-quality 3-D imagery over the Internet. In October of 2004, Google acquired Keyhole and Google Earth was born - bringing the kind of content previously available only in government and industry research labs to people everywhere.
And the story doesn't end there. Once people started using Google Earth, they started asking questions. Good ones. For instance: Why are some parts of the globe blurry, and others crystal clear? Where do you get your imagery? And how often do you update it?
Most people are surprised to learn that we have more than one source for our imagery. We collect it via airplane and satellite, but also just about any way you can imagine getting a camera above the Earth's surface: hot air balloons, model airplanes - even kites. The traditional aerial survey involves mounting a special gyroscopic, stabilized camera in the belly of an airplane and flying it at an elevation of between 15,000 feet and 30,000 feet, depending on the resolution of imagery you're interested in. As the plane takes a predefined route over the desired area, it forms a series of parallel lines with about 40 percent overlap between lines and 60 percent overlap in the direction of flight. This overlap of images is what provides us with enough detail to remove distortions caused by the varying shape of the Earth's surface.
The next step is processing the imagery. We scan the film using scanners capable of over 1800 DPI (dots per inch) or 14 microns. Then we take the digital imagery through a series of stages such as color balancing and warping to produce the final mosaic for the entire area.
We update the imagery as quickly as we can collect and process it, then add layers of information - things like country and state borders and the names of roads, schools, and parks -- to make it more useful. This information comes from multiple sources: commerc
I sure wish Google Earth had a way to adjust the brightness/contrast of individual tiles or maybe the view window. Some areas are very dim and need brightness/contrast adjustments.
Anyone who has thought about this for more than half a second, or has looked at anything more than just their backyard would realise that it is cobbled together from various sources.
Engineering is the art of compromise.
This makes it sound like Google actually did this work themselves with mental images of Googlites flying kites and riding hot air balloons. That is patently untrue. Most of the images in Google earth have come from other sources (government agencies, scanned aerial photos, etc).
Engineering is the art of compromise.
What are "international governments"? Did I miss something? I thougth there were international companies, organizations... but governments... even EU is still a bit away from that.
A friend of mine is a local flight instructor and has done a few flights for Google Maps crew. Perhaps they were just doing specialized by-request work, but in this case it was a dude with an SLR and a big lens shooting out the window of a Cessna.
I was skeptical too, but that’s what he tells me.
Quantum materiae materietur marmota monax si marmota monax materiam possit materiari?
Did anyone look at the date attached to the article (on its URL or title?) April 1st 2006.
Nice one Zonk. Not only a year out of date, but a spoof article in the first place.
I was one of the Aerometric-Alaska flight operators that took photography in 2006 while on-board a variety of small planes. The film we used was generally Kodak 2444, with 9' x 9' shots. After development, these prints can then be scanned at a resolution comparable to roughly that of an 11 megapixel camera. As the article states, these photos are usually taken in succession with 60% overlap. This is what has allowed people to generate topographic maps for decades, even before complex computer interpolation and computer graphics capabilities were present. Stereoscopic perspective of the same area of land taken from 2 separate angles allows people to determine differences in height, in case anyone has ever wondered how that worked. Nowdays, surveys and digital radar scanning is where most of the information that modern topography uses tends to come from.
4275 Athens-Boonesboro Road, Lexington, Kentucky 40509
r ls=en&q=4275-athens-boonesboro&btnG=Search
y j8t&style=o&lvl=2&tilt=-90&dir=0&alt=-1000&scene=2 023607&encType=1
Seems an appropriate opportunity to ask the question: Why the fuck is this residence blurred out? It appears to be someone who is a planholder in Kentucky's state health care plan, so maybe they're a powerful state government official:
http://www.google.com/search?hl=en&client=safari&
BTW, why are the addresses of all Kentucky state planholders publicly available and indexed on Google? That is just pathetic data security...
Anyway, the same address is accessible (and not blurred) via Microsoft Live!:
http://maps.live.com/default.aspx?v=2&cp=q9wwps7y
And appears to show two residences with pools in the back yard. Nothing to hide. Property records indicate that they were formerly owned by a lawyer named William Hurt, who practices in Lexington but now lives at another address. Given the rather inconspicuous pictures of them at the Microsoft Live flyover, the fact that they're blurred out on Google Maps is even more conspicuous than just showing the pictures of the two houses that are blurred.
There may be a high-powered state government official living there, but how did they have enough influence to get the pics blurred out? Were they skinnydipping in the pool? I don't think the map would show enough detail to make that a problem. Any ideas?
I still can't see my house on Google Earth, all those corporations etc. complaining about how GE is showing a building site where there's now a building or wotnot and all I see when I look at the area I live in is a patch of blurry green. Sucks.
To do something right, you often have to roll up your sleeves and get busy.
That's weird. Yahoo maps shows it as well, but at a lesser zoom level. That makes me wonder about california. Do they blur out barbara streisand's house? Anybody know her address? :)
Do you even lift?
These aren't the 'roids you're looking for.
Google Earth used to be cool, but it's turning into one massive billboard (perhaps one of the ideas all along). In Sydney for Australia Day, Google (and whatever the Microsoft's copy of it is called) did flyovers with huge pre-publicity. People lay out banners, .com wannabees stuck huge logos on their rooves, people picnicked and love-maked all on the hope of becoming 'famous' (with four million other people). Google put it up and at the end of the day, Sydney wasn't Sydney any more. Instead, Sydney was transformed into one big banner ad:
- day-flyover/
n s_demolished/page2.html
http://googlesightseeing.com/2007/02/27/australia
Then we had the world's biggest photojournalism fakery with Google restoring New Orleans to pre-Katrina. Beyond weird. Did they think the residents wouldn't notice?
http://www.theregister.co.uk/2007/04/02/new_orlea
Google Earth is sponsored infotainment. If you'd like to see Earth without the Ads, there's a little mob called NASA I hear are going places: http://visibleearth.nasa.gov/
The process he described is the same process that imaging companies have used since LONG before Google Earth acquired Keyhole. And many of those companies are still doing it. In fact, many of them are the same companies from which Google is now acquiring the imagery used in Google Earth. Does this guy really believe Google is conducting their own overflights and sending up their own balloons? Does Google now have their own satellites, too?
Microsoft's site shows it clearly:
4 ~-84.419424&style=a&lvl=19&tilt=-90&dir=0&alt=-100 0&scene=2023607&sp=Point.q9x2067yygqs_4275%20Athen s%20Boonesboro%20Rd%2C%20Lexington%2C%20KY%2040509 -8534%2C%20United%20States___&encType=1
http://local.live.com/default.aspx?v=2&cp=37.9793
The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
Due to weather and difficulty getting local permissions, Google was only able to capture a small part of the Sydney area they planned, and at different times than they'd stated, too.
As a result, there's no user-created ads visible at all in the new imagery, anywhere.
Why would anyone engrave "Elbereth"?
If you think a regular flight is boring, you have never been the pilot on a picture taking flight:
1. You fly straight (GPS and autopilot) for half an hour, then
2. turn around, and fly back.
3. Repeat this until the fuel is used up.
4. Refuel and repeat.
The only fun thing to do is when you turn: with the google photographer on his stomach with the camera, you do a Chandelle or Wing-over http://en.wikipedia.org/wiki/Aerobatic_maneuver This gives you a few seconds of weightlessness, and with the photographer in the back now floating in the cabin, he smacks on the floor with an "ooommpf" when gravity is reapplied.
The first few times he complains, but you just tell him you have to do this to properly align the aircraft for the reverse leg of the flight pattern.
So the routine for the photographer is something like:
1. click, click, click, click, click, click, click, click, click, click
2. "Whoooooooooo, ooommpf"
(I wonder if he reads this?)
don't cut it off www.mgmbill.org
The camera's mode, at least in Canon's case, is to show an overlay of the pictures already taken in the matrix or panorama you're taking. It's easier to get good, overlapping, easy-to-stitch images if you use the camera's framework to help you set up the shots, and be sure when you've taken enough to fill the planned matrix. As a bonus, the pictures are all tagged as to their position in the final photograph, and all the camera data is recorded for the stitching program.
IIRC, the actual stitching still happens in software on a PC.
Can you be Even More Awesome?!
Any ideas why they do so?
I was on vacation in Malaysia last year. So, of course, I checked out the tropical paradise island I had been to when I came home. To my my surprise the island had disappeared in those few months, it was no longer available in Google Maps. Q: Should I have more baseless destinations in the future?
So Google is basically saying that anyone willing to help them out can go fly a kite?
Hmpf.
Beware: In C++, your friends can see your privates!
While Google Earth's pictures are fanciful I wish they would focus more on refining their geoidal datum. Plotting latidude/longitude coordinates are way off the mark, and seems to vary depending on locale. I also found a number of mistakes that I haven't found elsewhere (indicating source) such as the spelling of a park or name of a building, but Google seems content on ignoring my corrections.
Yes, it certainly could be a government conspiracy of some kind. Or it could be a spot of oil on the film. But the conspiracy idea is so much more fun.
http://www.boingboing.net/2006/09/28/google_maps _reveal_w.html
I have a 10Mpixel camera and an airplane. If I took a bunch of photos from an area not yet covered by them, would they add them to their Map/Earth for free? Cause flying around and taking photos isnt a great expense - its the processing and orthorectification...
www.tribalnetworks.org - helping tribal people around the world to own their own means of high-tech communications
This overlap of images is what provides us with enough detail to remove distortions caused by the varying shape of the Earth's surface
<pedantic>The earth's surface shape does not cause any distortion: it is wat it is. Your method causes distortion in the repesentation of the earth's surface</pedantic>
Sorry, couldn't resist.
amazing business procedure.
There's a road going north from here which fades out, reappears 20 yards to the left for 100 yards or so, fades out again and goes back where it's supposed to be, etc.
Then there's the difference between the terrain height and the images - big lumps in the middle of the sea.
No sig today...
tinfoil hat at the ready.
If Google really cared they would fix Android Chrome to reflow text, instead of discriminating
"Then we had the world's biggest photojournalism fakery with Google restoring New Orleans to pre-Katrina. Beyond weird. Did they think the residents wouldn't notice?"
No, they thought they were intelligent adults instead of idiots. Nowhere in the world is the completely correct (surely not around here) BECAUSE ITS NOT REAL TIME. They get the best quality which is fairly close. Those of us with 3 digit IQ's understand that.
"Google Earth is sponsored infotainment. "
Indeed, if you want to find a pizza place you can do it fast.
"If you'd like to see Earth without the Ads,"
You just use Google Earth since no adds pop up.
" there's a little mob called NASA I hear are going places: "
Not in the real world, they could never afford to make it a worthwhile program.
If Google really cared they would fix Android Chrome to reflow text, instead of discriminating
Those 'big lumps in the middle of the sea' are nothing but humpback whales, you insensitive clod!
You can add place points, and attach net based jpegs as overlays, you can adjust the size/angle/alpha.
JUst split your images up and place them in the correct order, then publish the placeholders and any client will see your photos overlayed
at the right location, if you did it right. I did this to one ski field that was mapped poorly, so I added a plane based aerial photo of it on top. Looks real good
and great res, and png is not too large.
Liberty freedom are no1, not dicks in suits.
Deckard: Enhance 224 to 176. Enhance, stop. Move in, stop. Pull out, track right, stop. Center in, pull back. Stop. Track 45 right. Stop. Center and stop. Enhance 34 to 36. Pan right and pull back. Stop. Enhance 34 to 46. Pull back. Wait a minute, go right, stop. Enhance 57 to 19. Track 45 left. Stop. Enhance 15 to 23. Give me a hard copy right there.
Antarctia is really badly mapped, I know its no amazon, but it would show of its beauty more.
Hasnt Nasa mapped it well? Buy it google.
Liberty freedom are no1, not dicks in suits.
Does anyone know how often the maps get updated, or if ever? I started building my new home over a year ago, and have been living in it 7 months now, but the maps of the entire area are still obviously several years old. I know this because there are several entire neighborhoods that have been built up over the last 5 years that are not there either. This is on both Google maps and earth.
(Stolen sig) Remember: it's a "Microsoft virus", not an "email virus", a "Microsoft worm", not a "computer worm
The Leonard P. Zakim Bunker Hill Bridge
I always figured there simply wasn't an adequate weather for a satellite flyover to get good pictures in a while, but if they can do it with planes, etc...
Something of the magnitude of the Big Dig is a pretty notable event for a major city, and you'd think they would at least update it for Google Maps' sake. At this point it seems that the maps are correct, but the imagery isn't. Very misleading to those who "don't trust those computer mapping thingamajigs"
CAn'T CompreHend SARcaSm?
Islands?
Ceci n'est pas un sig.