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Google Releases Key Part of Street View Pipeline
New submitter drom writes "Google released a key part of their Street View pipeline as open source on Tuesday: Ceres Solver. It's a large-scale nonlinear least squares minimizer. What does that mean? It's a way to fit a model (like expected position of a car) to data (like GPS positions or accelerometers). The library is completely general and works for many problems. It offers state of the art performance for bundle adjustment problems typical in 3D reconstruction, among others."
Does it come with built-in Wi-Fi snooping?
It pays to be obvious, especially if you have a reputation for being subtle.
Good effort I guess, but there is much better technology out there.
Mind telling us what are the "Better Technology" ?
Thank you !
Muchas Gracias, Señor Edward Snowden !
Does this edge-case spotting count for a spotter's fee?
Your comment suggests you don't know what at minimizer is, and I think you just wanted to say "Google is bad" to the first story related to Google.
Which is a pity, but smarter trolls than you will have a go at them later.
If this is a constrained minimizer then Libre Office and Open Office will suddenly get a major improvement in their solver functionality for example, because at the heart of a solver is a decent non linear minimizer.
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Fox News loves Bin Laden, hates President Obama for killing him.
I'd imagine it's probably because you're a troll.
Can any math pro explain what practical uses solving nonlinear least squares equations have? The Wikipedia page is to high-brow for me. :)
Football Odds
"git clone https://code.google.com/p/ceres-solver/" asks you for account with real name?
What exactly are you talking about?
The video shows you how they use it, not what it is. Parent is just trolling.
Take a curve, represented by some function with parameters.
Take a set of data points.
Fit the curve to the data points by changing the parameters.
Minimizing the error distances between data points and curve so you get a best fit.
It's easy enough for lines and polynomials, but for more general functions it becomes a real pain. The maths is straightforward, but the implementation can make a huge difference. Google's library looks like a well implemented minimizer and it's been road tested too.
This is good.
From the source code:
Yeah, that's pretty much how maths makes me feel as well ...
When you have several measured points, and you want to fit a function to them, least squares is how you measure how closely your function fits. This is useful anytime you want to infer a trend into the future (extrapolation) or infer what values come between the measured values (interpolation).
If you can speed up least-squares calculation, you can test your theories faster and possibly using less hardware - making that kind of statistical analysis more accessible.
In Google's case, they are using it to adjust their raw GPS data so that they can get a more accurate idea of where they are.
Slashdot isn't stagnant because of the shit quality of the site and the Video section and new BIsexual section. It's because a story like this, is the root of what slashdot was. And it has 30 comments.
That's why this site has gone to shit.
Well, I did some 3d reconstruction so I can answer that. The deficiency (not so important for most potential users) is that methods mostly 10-20 years old, no latest methods present. In robust estimators sections ("robust cost function) only "soft" L1 estimator present, no nonsmooth L1 estimators with solvers based on thresholds like Split Bregman and others. No constrained minimizers (solvers) which use Interior Point, Augmented Lagrangian etc. No dense and patch based reconstruction methods support. No global minimization methods(divide and conquer, convexification) I can continue here, but that's not a point. The point is that this package probably for industry users, not for researchers or people who want absolute cutting edge to squeeze maximum out of hardware or have difficult input images. That could be considered to be intentional, because more methods mean more choices, more approaches to test, more parameters to tune.
Woa, very timely slashdot!
from file download:
Released: (2 minutes ago)
Uploaded: Today (2 minutes ago)
With this code, one could develop an application that can automatically render a 3D model from a series of images or a video. In other words, you could use a camera to "paint" a nearly photorealistic 3D model - no hours/days/weeks of Blender/CAD work to create a model, just scan with cheap camera. They state, "We have a working Android port but it's not ready yet." Envision an Android app that does this - scan your friends or nearby person into a 3D model - get complete geometry (height, calculated weight, other dimensions).
Where is there a solver in open office?
I also wanna know (can't check now), but there's probably some regression routines in spreadsheet thingie.
The video at the Ceres Solver page reminded me a lot of the RatSLAM project. A project about mapping streets using a single camera as the only mapping sensor.
Related video here:
http://www.youtube.com/watch?v=-0XSUi69Yvs
RatSLAM paper here:
http://eprints.qut.edu.au/32812/1/32812_Milford_2011000124.pdf
Sig? Heil