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Measure Anything with a Camera and Software
Kevin C. Tofel writes "Using a simple concept, iPhotoMEASURE software can measure any objects you can take a picture of. Include a printout of a 7.5- or 15-inch square in the photo and the software can measure any distance or object in the pic to within 99.5% accuracy. Although geared towards contractors, there's any number of consumer usage scenarios as well. Enough to justify a $99 price tag? Jury's still out on that."
$99 is a bit damn steep if you ask me.
...someone writes an OSS version of this? Has anyone started on this yet?
Yeah. I could *really* see your average general contractor using this.
I thought this was some kind of cool new perspective-based algorithm or something, but it turns out you have to be able to get close enough to the object to stick a label of known dimensions on it. The software justs compares the size of the label with the size of the object you're measuring. I'm not paying $99 for that.
There are already a number of laser rangefinders with compasses built-in that can do the same thing using simple trig.
This space intentionally left blank.
... for all of us guys. The subject of how to measure with a with a tape measure has long been a controversial one, and thus the size debate has been marred by a lack of common consensus. This gadget will settle things once and for all!
I hear there's rumors on the Slashdots
Now where am I supposed to come up with a 7.5" square? I threw away my tape measure.
You take a photograph of a bathroom or kitchen containing hundreds of square tiles? Digi Target that baby...
Seriously people - buy a measuring tape. Its not that difficult.
Nothing witty
This is rather cool. Is there anything like this in the OSS world? I would not be surprised if there is soon!
---- "XML is like violence. If it doesn't fix the problem, you aren't using enough."
My cousin does this manually, using pictures of job sites and items on known size, to estimate needs.
$99 is nothing. If it can save material purchased for a big job it will most likely pay for itself instantly, not counting all the time saved photographing and measuring that is now with manual processing afterward.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
Would be to project a laser 'shape' from the camera to compute distance, and keep the entire measurement operation localized within the camera.
Just a thought.
------ The best brain training is now totally free : )
just need to snap it again with the reference object in it. http://btc.montana.edu/ceres/html/Universe/images/ cobe.gif
Cute gimmick. For framing, if it doesn't need to be all that accurate, +/- 2", why take the time? For finishwork, if it has to be within 1/8", better to take dimensions directly to account for things being out of plumb or not quite square.
Honestly, I could see almost every contractor getting into this...
I think people need to realize that this will be it's major market as surveying costs run in the $20~30/hour range for a single trained surveyor... this is skilled work. If companies can instead send out untrained (or barely trained) individuals at $10-$15/hr with much less time spent in calculation and only a $100 sunk cost into the software there is no reason they wouldn't choose this method. Very good news for contractors, bad for surveyors.
The price is almost low enough for consumers with a need to calculate distances relatively regularly to purchase this software.
The original generic sig.
If I take a picture of an arch with something in the background of the arch there's no way it's going to be able to measure both the foreground and background distances without any knowledge of the distance the objects are away from the camera etc...
You'd have to stick known distance marks on everything in your picture.
thank God the internet isn't a human right.
You can not measure arbitrary dimensions in a single photograph using a single calibration target. If you stick the target onto a surface you can measure dimensions on that surface, i.e. parallel to the target, but you would have no information about locations not on the plane of the target. If you are not convinced just think of it this way - any point in an image can be at an arbitrary depth.
/. fell for it, hook, line and sinker.
This means two things, either you provide the software with more information or you need a calibration target for each plane of measurements in the image. For the latter case I could write the software in an afternoon (Excluding testing, writing a manual etc.), and already have my own research tool that does precisely that, so $99 is extremely steep. For the first case such a piece of software would not be 'easy to use' nor quick, though probably worth the $99 and your money back for mis-selling.
Sounds to me like that company's marketing team is overselling there product, and
But what really gets me is the claim in the advert, claims that hyperbolic if not outright lies. I can easily construct a photo in which a house appears to be the same dimensions of the squares. One more effective way to do what the software is proposing is to know the dimensions of a feature that is part of the object you wish to measure, and use similarity to approximate the dimensions of the smaller or larger object.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
Are you fucking kidding me, that is childs play.
First of all, If I can put a sticker on it, why not just measure it ? Second of all, for this to be at all usefull it would need to be able to measure in the micro (100ths of a millimiter) or macro (100s of meters) domain, and also be able to compute the size of any object in the distance based upon the size of an object in the foreground. I thought I was going to read how some clever mofo had figured out paralaxing or something, but no. Basically this is $99.00 for a pixel counter !
Stupid.
From now on any girl I meet online will be required to send me a picture with one of the squares in frame. No more "just a few extra pounds" for me.
Hurray for proportions and high school trig!
Hang on, how can this thing possibly work?
By putting the reference printout in the image you can determine the distance and orientation of the reference, but how does that tell you about the distance to other points in the image?
It can only work for points in the same plane as the reference printout, such as the features on a flat wall.
It cannot tell you anything about the dimensions of a complex object like a car.
There are systems I've seen that can do similar jobs using video or multiple images to triangulate the 3D structure, but the FAQs on the iPhotoMEASURE website repeatedly refer to taking a single photo.
For $99? I'll stick to a tape measure.
Karma police, I've given all I can, it's not enough, I've given all I can, but we're still on the payroll.
Seems like a piece of software that would only be useful in a few applications, but VERY useful in those applications.
It's not going to be useful to someone who needs precise measurements, like a contractor. Those people will use a measuring tape, which is more than 99.5% accurate when used properly.
But for estimators and appraisers this sounds like a killer app. Usually one would charge a lot more than $99 for such a niche application. Because of its niche status, there will not be as much competition from other software vendors. And for the intended customer, it is likely to become a must-have item.
Of course, the more they charge, the more likely it is that competitors will materialize.
"iPhotoMEASURE" ? Sheesh... They might as well have gone all out: iPhotoMeasure X 2.0 BETA I hope the folks at KDE don't do the obvious when they make their open source equivalent.
All it does is count pixels. Take the picture with the known size block in it, then count how many pixels the block takes up: that's your dots per inch -- for objects the same distance away as the known size image. I read somewhere that the Japanese (I think) used to do this at musical instrument trade shows, by wearing a 1 cm square tie tack and taking photos of each other holding instruments. They could get the dimensions of the instrument from the photos that way, and make great cheap knock-offs.
I hope sites like adultfriendfinder and lavalife don't incorporate this software into their user-options.
...
.... <runs away>
wait a minute
yes I do, I do hope sites like that make this feature available to their users.
---
adult friend finder?
Ace
They should make a $1299 "Professional" version, quick. It'll be the exact same product as the $99 version, just in a different color, and with a printed, spiral-bound manual.
It's definitely possible to under-price your product if you're not careful. Actually, having a $1299 version might even help drive sales of the $99 version, because people would perceive the $99 version as a sort of 'deal,' as in "hey, for $99 I'm getting 60% of the features of the $1300 version! That's great! I'll take three."
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
But since it is not 100% accurate, then its trash.
You do know that's impossible, right? I could use a laser interferometer, and determine the distance between two objects down to a fraction of a nanometer, and it would still not be "100% accurate."
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
...but does it also measure in the Metric system? I only see Imperial units in the article.
Considering the shoddy construction I've seen in many modern homes (mostly in the one I shouldn't have purchased), 99.5% measurement accuracy for a contractor would be an improvement to today's state of the art. Maybe they could come up with a hangover or coke filter for the software to even out the playing field of man vs machine.
Seriously though. Nut up and buy a friggin' tape measure.
I was taking a mechanical design class, and I wanted to know the coordinates of a bunch of screwholes in a mounting plate. I looked at it for a second, grinned, and darted to the nearest computer with a scanner -- as my teammates shook their heads (and micrometers) at me, saying "damnit, you're being impractical; it'll never work." (They thought I was too interested in theory and not enough in turning the cranks on lathes and mills; though we generally got along, we did have -- philosophical differences.) Scanning took a few seconds, after which I took a minute to note the pixel coordinates of the hole centers in a spreadsheet. Then I measured one edge of the part with the micrometer to get a pixel-to-inch scale, popped that number into the spreadsheet, and out came the x,y coordinates of all the holes in the part. When we CNCed the new plate with those hole locations, they all lined up with the part-to-be-mounted perfectly -- at which point they were pretty much forced to admit that maybe the kid knew what the hell he was doing!
I've thought since then that some software designed for the task (with edge-recognition algorithms, measurement features, etc) could turn consumer-grade scanners into decent reverse-engineering tools (for planar parts).
That link doesn't work (at least, not for me). I think it looks at the referer and won't let you deeplink to the image. You have to go through the blog to see it:w _to_measure_.html
http://jkontherun.blogs.com/jkontherun/2007/02/ho
Looking at that photo, I'm not buying that it can measure all those distances from a single photo. I think there is some advertising hyperbole going on here. I get that you could measure all those distances and dimensions, using multiple photos -- one each of every flat surface, moving the target each time so it's the same distance from the camera as the surface being measured -- but I don't think it would work from a single photo.
The only way you could measure everything from a single photo like that, would be if the camera was stereoscopic, or had some other form of depth perception. Otherwise, as you noticed, there's no way for it to know that the window that's closer to the camera is not really bigger than the garage door that's further away.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
http://i78.photobucket.com/albums/j113/ffutahw/gue st_house.jpg
Look! a 3 foot tall house!
I think people need to realize that this will be it's major market as surveying costs run in the $20~30/hour range for a single trained surveyor... this is skilled work. If companies can instead send out untrained (or barely trained) individuals at $10-$15/hr with much less time spent in calculation and only a $100 sunk cost into the software there is no reason they wouldn't choose this method. Very good news for contractors, bad for surveyors.
No, this may be good news for truly talented surveyors. It seems a lot like the situation involving software developers and outsourcing to India. At first the situation will look bleak: some other people are offering the same services as the professionals, for only a fraction of the price. Soon enough, some managers will choose to go the cheaper route.
When it came to software, the industry eventually found out that Indian developers just plain couldn't put together a usable product. Often times, what they did produce was virutally useless. I've heard of situations where those off-shore developers took code from a number of open source projects with incompatible licenses, merged it all together in a basically non-functional monstrosity, and then expected to get paid for putting out that piece of pure shit.
Of course, this was a great thing for us North American and European developers. It made those of us with even just decent software development skills look great, when compared to the Indian developers. We could end up asking more, since the smarter managers learned our true value.
The same thing could happen for surveyors. After hiring a few untrained people to perform surveying using this device, it's no doubt that there would be major and costly problems. Building foundations would be unaligned, for instance, and professional surveyors would need to be called in to get things measured correctly. Now they'll be in a better position to demand more pay for the same service they were providing before, as the smart managers will realize that their other option will make major mistakes, and be even more costly than just paying a professional to do it correctly.
I just heard something on the radio the other day that sounds the same and now i can't find any mention of it, but basically it said that cops have something very close to this type of software now and are using it to clear accident scenes quicker. instead of having to measure by hand every aspect of the accident, they take a decent amount of pictures and use the software to calculate distances.
this is just a placeholder till i send back my real sig from the future.
That Polar Bear in the snowstorm is gigantic!
-- www.globaltics.net
Political discussion for a new world
It doesn't seem like it would be really too hard, if the software is just doing what I think it is.
The hardest part is just picking out the target from the photo. In most interior scenes, the target they're using would probably work pretty well (it's a white square with heavy black edges) although it seems like there are some backgrounds where locating it might be a problem. But there are, if I'm not mistaken, some OSS efforts to do things like automatic facial recognition, and that's a much more complex problem than picking a black-on-white box out. (Particularly if the center of the box is reflectorized, so that it's always 255/255/255 when a flash photo is taken.)
Once you've located the target, knowing it's actual size and how many pixels wide it is in the image, then you can let the user pick any two points elsewhere on the image (which must be in the same plane as the target, and basically perpendicular to the camera's film/sensor) and tell them how far the points are apart in reality. It's just multiplication at that point.
If you look at OSS image-processing software, there are applications around that do much more complex stuff than this: Hugin, and Panorama Tools (the latter are what really do the heavy lifting) come immediately to mind. Compared to joining and sewing a panorama, this kind of measurement seems pretty easy, unless I'm missing something critical.
If I was recommending features for a measurement product, I think the key would be not to limit it to a particular target. Sure, a few printable targets, similar to the one used in TFA's commercical product, would be good for measurement of rooms and houses, but it would also be nice to use smaller things that are typically used for scale in macro photographs. E.g., dollar bills, quarters, width of a pencil, etc. Those would be tougher to automatically recognize, and would probably require some prompting by the user in order to pick out, but would probably appeal to a wider variety of users. Who hasn't seen an eBay photo and wondered what the exact dimensions of something were?
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
Does it run on linux?
anybody ever seen the italian job?
This sounds pretty cool if it works as it is being described. Great asset for surveyors, construction, law enforcement and the neighborhood UFO photographer
Just find a company which provides photogrammetry software. I worked for one once (Alias ltd. in the UK). They take a stereoscopic pair of photos of a site (with markup stickers here and there) and the software builds a 3D CAD model of all the pipes, vents, supports, walls etc.
Cress, cress, lovely lovely cress
There are some subtleties in measuring things from an image. Lenses distort images in a non-linear way, so just counting the pixels wouldn't be extremely accurate. One of the ways this can be improved is by calibration, basically taking a picture of a bunch of dots in a square array that covers the whole field of view, and do some math. Hey iPhotomeasure people, if you need a consultant for version 2, "with improved calibration" give me a call!!
There is this German company making the product "DartFish", that does that in Videos. Great for analyzing sports, like the distance and direction of steps before jumps.
Price tag is (afaik) well below 500. I only saw demos with sports people and I must say I was REALLY impressed (keep in mind the geek factor of sports men when it comes to IT).
Ah and it was like 2 or so years ago. I refrained from buying it, because I saw no use in bicycling and it was protected.
Don't ask me how this works, but I really thought it was impossible to do. You could even mark stuff in scenes and you could do it real time - like pulling the high jumper from the mattress in front of your laptop.
A lot of these comments are saying, "it's just a pixel counter", or, "it can't work", or "you would need to do xyz and it is not worth $99".
Of all those comments, how many people actually tried it to see what it can do? Maybe the people who designed it figured a lot of this out and have some way of doing the calculations to make it work properly.
Just because 'YOU' can't see how to do it, does not mean the designers could not figure it out.
Because I can't figure out how to determine trajectory through the earth's gravitational pull, to the vacuum of outer space, calculating where mars will be several months (maybe years) in advance, then mars gravitational pull, to land a rover on the surface does not mean no one else has figured it out.
Perhaps the people at NASA are just smarter than I when it comes to that, like it is possible the designers of the software might just be smarter than those who never seen the software work but claims it can't work.
Just a thought.
I'm a Ski Patroller and we investigate accidents by taking pictures of the scene with little flags to mark distances. If the software works as well as described, this would allow us to just take pictures of the scene and not to have to carry flags and a tape measure. Investigations would be faster and easier.
It may be possible to get ARToolkit to do this. It's dual-licensed under the GPL so it's OSS. If you want to play with it just get a v4l video capture device and print out the squares.
:) Thanks Wayne Piekarski from UniSA for letting me play ARQuake on that thing at linux.conf.au in 2003.
ARToolkit's been used by the University of South Australia to create ARQuake which is a lot of fun to use with the actual wearable computer
I'm not sure if they used ARToolkit or something more in-house to make Tinmith, that looks really sweet.
The beatings will continue until morale improves.
The marker looks very similar to those used in the Open Source ARToolKit - http://www.equator.ecs.soton.ac.uk/projects/artool kit/ - it uses known-size 2D barcodes to get the 3D transform of the camera relative to the position of the marker. Would probably be straightforward to extend the ARToolKit to be able to do this.
I swear I remember reading an article about kitchen design software that placed a stick of known length in the picture (at an angle to give it depth). I think they took a few pictures from different angles or something so the software could understand "depth".
Why don't you get to work finding the reference for me, or if you can't just rewrite the software. Thanks.
Because now they can measure there penis using a camera.
What will it do in this room?
s es%20Material/www.illusionworks.com/html/ames_room .html
http://www.psychologie.tu-dresden.de/i1/kaw/diver
The NIH has a free pixel counter you might try before shelling out $99 bucks. You'd just have to use a known size object, use the app to measure that object in pixels, then enter in the pixels/unit value. It's meant for biologists, but it has some nice features, like the ability to recognize objects ("particles") and 3d representation of pixel intensities. http://rsb.info.nih.gov/ij/docs/menus/analyze.html
The problem there stems from the fact that this seems to be little more than a pixel counter. I.e., to measure something you'd have had to stick the label on it and to have taken a nice full frontal picture of it.
So the way I see it, if you remembered to do that, then you pretty much remembered to measure it in the first place. If you didn't, well, you're going to go back anyway.
And if it shows up at the right angle in the picture of something else you did measure, then it doesn't do anything you couldn't have done with any graphics editing program. (E.g., Gimp as a free one.) You don't even need a CAD program. If it shows you the pixel coordinates of the mouse pointer, there you go: measure the known object in pixels(the difference between the coordinates at one end and the ones at the other end), measure the unknown object in pixels, do some elementary maths. You'll have the same accuracy this thing has.
A polar bear is a cartesian bear after a coordinate transform.
Matrox Imaging has been offering a software product known as the Matrox Imaging Library (MIL) for years which provides standard measurement functions and now even a metrology module that measures arcs, tolerances and more.
Best of all, it supports Windows AND Linux!
If what they're advertising is true, then it's more complicated than that. Pixel counting alone would only allow them to accurately calculate the length of line segments that are both the same distance from the camera and orthogonal to the camera's view axis. Even then, it would be hard to achieve 99.5% accuracy in many cases because the edges of the calibration block probably don't line up very well with pixel boundaries. So to provide a reasonable guarantee of accuracy on that plane alone requires the ability to extract sub-pixel information from the image with reasonable accuracy.
To calculate lengths that are not close to lying on that plane is more complicated. The software needs to be able to very accurately account for perspective, which involves doing a pretty respectable amount of analysis. There's been a lot of research into that and I'd actually be very surprised if this were the first commercial software to do something like that, but it's still a non-trivial problem.
There is open source software that does this. ImageJ is a free open source java software that does just this. It is well known among scientists and was developed by the NIH. Best of all, you get to choose your own calibration device. I've used it to measure biological specimens of sizes 1-3mm in size from a high resolution photograph taken with a Nikon D100 together with a 1/2 inch calibration block. I've been happy with the results. Besides measurements, it does a whole bunch of functions like counting particles and image processing
Since it is java based, there are versions of Windows, OSX and Linux. Of course it does not address perspective problems, but that is not an issue for me as I can keep my calibration device in the same plane as the item I am measuring.
"I took a picture of my dick which I swear to be 8 inches, your honour, but the software said it was only 5 and a half!"
I used to work for one of the biggest wallpaper producers, and they were going to buy a similar program where the user prints out a sheet with some kind of arrow on it, and put it on the wall. After that, the user would take a picture of his room, and load the jpg in the application. From there, the application would calculate the angle of the wall etc, and the user could load any texture (in our case, wallpaper) and it would apply it the the user's picture of his own room. It was pretty cool, but unfortunately not web-based, it had to be given to users on CD, because it was pretty huge...and the license didn't allow just distributing it on the website..
Its called AutoCAD, photoshop, or just about anything that you can use a frame of reference for. If you gave me a picture of a building, and gave me the dimensions of one of those bricks, I'm pretty sure I could accurately estimate the dimensions of the rest of the building. Once you draw the line on cad you scale the drawing up or down to match the line you drew with known dimensions. Its really not that complicated of a process. I really need to start designing software for contractors because apparently they'll buy anything to shave a few seconds off. Next up, a program that counts bricks!
You fool! The reference object IS in the picture! It's just a little difficult to make out a 15-inch square in a picture of the entire universe...
I have never been bothered by Slashdot or posted to it seriously, but this is just to establish "prior art" or something like that.
m l given with photos with square areas, can measure distances, place 3d objects in real-time like granites and even tone the lighting color (which is the extension)....
My project http://www.cs.utexas.edu/users/perumaal/cs384g.ht
(The areas in the photos are blacked out for privacy reasons)
However the math is trivial and the idea is good but it does way bit more than "stick the label in your surface to get the distances". It actually is a 3d modeling tool.
the ubiquitous "grey card" from Kodak was long used in the chemical-photo world as a standard measurement of both distances and color density. you KNEW you had an 8x10 element in the photo.
if this is supposed to be a new economy, how come they still want my old fashioned money?
I wonder if you could fool it; like if you gave it a shot from the Lord of the Rings, where both Frodo and Gandalf appear. I think you could probably even have two different boxes drawn out, one for if you're using Frodo, the other for Gandalf (since Sir Ian Mckellen and Elijah Wood are a meer 5 inches apart, but in the movie, it seems that there's feet between them)
Unless more more than one photo is used with computer vision algorithms to actually build a perspective (two or more eye view) this thing is only going to produce approximate measurements.. not good enough for anything worth using it for.
99.5% is also no good unless you don't really want to measure things accurately.
The example shown in the link shows a garage that is farther from you than the windows, and the windows are not directly in line of sight but actually off to the side a little.
I think it would really only be useful if you have a very high resolution digital camera and stand quite far from the building. But for closeup work you might as well have a ruler.
It would be useful for things you can't reach though, if you can get directly in line with it.
Unless more more than one photo is used with computer vision algorithms to actually build a perspective (two or more eye view) this thing is only going to produce approximate measurements.. not good enough for anything worth using it for.
99.5% is also no good unless you don't really want to measure things accurately.
The example shown in the link shows a garage that is farther from you than the windows, and the windows are not directly in line of sight but actually off to the side a little.
I think it would really only be useful if you have a very high resolution digital camera and stand quite far from the building. But for closeup work you might as well have a ruler.
It would be useful for things you can't reach though, if you can get directly in line with it.
Five inches? That can't be right...
Perhaps due to the lens issues of modern (small lens) cameras.
c tionID=154&articleID=403323
This review claims more modest accuracy of 93% and 95% for outdoor ranges. (40', 30'):
http://www.remodeling.hw.net/industry-news.asp?se
Incidentally, it is totally possible to calculate a number of distances in an image of a rectilinear object (like a house or kitchen) by assuming that planes are at right (or other known) angles. One can then estimate on planes other than the reference plane. Any planes that are at a shallow angle to the viewer will generate crappy numbers, of course, and the more angles you are away from the reference, the more error will accumulate. Lens distortion is pretty frightening on a lot of cameras - I'd be curious if the software can measure it, or otherwise attempt to ameliorate that source of error.
Whether this software is effective in practice would likely require trying it, and having actual (as opposed to hypothetical) accuracy requirements for your estimates.
If it means a saved trip, that's $150 in billable time for a close job.
I got a Stanley FatMax laser distance meter last year - $99 shipped. I got it for an 8000SF church admin building I had to map. A helper and I did the whole thing - two levels and about 40-50 rooms total, including a labyrinthine lower level, in about 6.5 hours. I'd say it would have been a 2 day job with a tape measure. The best part is that once we got back, the building closed within an 1". Freaking amazing - I'd say we would have been off more with a tape.
Oddly enough, I just had to do something like this on a building I'm working on. It's old, so the brick coursing isn't quite 8". I doubt this does pincushion correction, which is a shame, as there was about 4" in my photo (printed with photoshop at 3/4" scale). Also, a little bit of perspective, though not bad for handheld. I suppose this might correct for pure perspective.
Is it just my observation, or are there way too many stupid people in the world?
Come on, thats freakin hysterical
...yesterdays article, throw in a little Google Earth for good measure (pun intended), and...I think you get the idea.
--
Franklin
If you bill by the hour, then this software will actually cause you to make a lot less money, because it saves you time, so you can't bill for as many hours!
-Don
Take a look and feel free: http://www.PieMenu.com
...there's a program called Snake Measurer which works pretty well. You just take an overhead photo (say of - oh, I don't know - a snake) and include something of a known size, like a ruler. Then you load it into the program, draw a line on your known object, enter the size of it and start placing dots on the subject you are wanting to measure. You end up with a length in the unit that you used for the known object. It's not 100% but it works pretty well. Best of all, it's free. As in beer. [Note: I have no attachment to the programmer(s) - I just have a snake to measure.]
From some of the comments and the description of the product, it sounds like a true boon to folks trying to target specific points within a compound they cannot enter. For example, naughty folks might be able to quite accurately mark targets using a photo taken using a know object/position in the foreground with the target in the distance. I suppose these folks could also be contractors, but it is likely they'll be building craters rather than nice warm, safe buildings. I'm sure someone must've said this before, but I missed it when I scanned the comments.
I'm surprised nobody's mentioned PhotoModeler Pro yet. While somewhat more expensive than this, it's quite powerful, especially with my 8 MP DSLR camera, and it comes to the top of all the searches I did on this.
It works a little differently in that you take multiple pictures, and mark points (or optionally use targets and have the software automatically locate them). With enough pictures (generally 3 or more, although 2 would be possible) and enough points, the software is capable of backsolving, locating all the points in the pictures in 3D. It's essentially the same idea behind the stereoscopic imaging your eyes do to measure distances in 3D with just two images, except much more flexible.
The basic idea is that you go out, shoot an object from a bunch of angle, then go back to your computer and mark up the photos. The program can then compute the coordinates. (If you want absolute distances, you'll also need an absolute measurement to establish scale; a picture of a ruler can do the trick.) Very handy, if also quite a bit of work.
This general topic is known as photogrammetry, which is the science of taking measurements from photographs, and generally involves solving a lot of big matrices to minimize errors on rays of intersection (if you're interested in the mathematical bits). With a known target to establish perspective, I wouldn't be surprised if these guys can establish a good set of measurements with just one picture. If you know distance (size), and field of view (camera focal length), and can establish relationships between points in the picture (this would work best for things in the same plane as the target, or at least at known, most likely right angles), then it's quite solvable.
Law enforcement would probably like this as a tool for photos of a crime area or accident it could probably also be used in conjunction with Google maps to do surveying given enough time.
no matter how good it is, it is human nature always wants to make things better
Whenever I see the "a few extra pounds" descriptor, I just replace "pounds" with "tons" for my mental image and it is always far more accurate than 99.5%.