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The new Photosynth

photosynth.net

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Re: The new Photosynth

#61

Post by kyberias »

Tomdarkness wrote: post #32

I think it could do with a little bit of information on the first page to tell you what it actually is. If it was not a highly voted link from HN I'd most likely not bothered to actually figure out what it is. Also in Chrome canary it frequently crashed the tab or gives the "WebGL hit a snag" message, which requires you to click reload before the site works properly again. Edit: Why is this been downvoted? All you ge…

You've been downvoted because your criticism is unwarranted. On the front page, there is a large link "Learn more" to a page that very clearly explains what PhotoSynth is. There's also a menu with similar info.

Re: The new Photosynth

#62

Post by archagon »

The samples are really, really cool. But it got me thinking: aside from a bit of parallax, what's the practical difference between this and 60fps video with a smooth/intertial seek slider?

EDIT: I guess not having to use a dolly for smooth motion is a huge plus. But the tradeoff, of course, is loss of quality in the interpolated "frames".

Re: The new Photosynth

#63

Post by Tomdarkness »

kyberias wrote: post #61
Tomdarkness wrote: post #32

I think it could do with a little bit of information on the first page to tell you what it actually is. If it was not a highly voted link from HN I'd most likely not bothered to actually figure out what it is. Also in Chrome canary it frequently crashed the tab or gives the "WebGL hit a snag" message, which requires you to click reload before the site works properly again. Edit: Why is this been downvoted? All you ge…

You've been downvoted because your criticism is unwarranted. On the front page, there is a large link "Learn more" to a page that very clearly explains what PhotoSynth is. There's also a menu with similar info.

That's not my point though, I'm talking about what you see when you visit for the first time.

If you visit the site for the first time, like I just have, you have no idea what it is. You are just looking at a large image with some additional photos in circles. Just a simple phrase, such as the first line from the Learn More page: "Capture [and view] the places you love in amazing resolution and full 3D.", and perhaps a "Try it, select a scene" on near the circles would make it much more obvious.

Or perhaps even better, when you visit for the time time give them a quick demo or walk through.

Re: The new Photosynth

#64

Post by nswanberg »

slacka wrote: post #57

I've been excited about this project ever since I saw the Ted talk by Blaise Agüera y Arcas. Here are some related projects. multiple photos: http://www.123dapp.com/catch Single photo: http://make3d.cs.cornell.edu/ http://www.3defy.com/ and http://hackaday.com/2013/09/12/3-sweep-turning-2d-images-int... video: http://www.3ders.org/articles/20130729-disney-new-image-algo... and http://punchcard.com.au/

That talk was was a lot of fun to watch. And the first half of that technology in the talk, Deep Zoom, is now open source: http://openseadragon.github.io/

Re: The new Photosynth

#65

Post by femto »

Another bit of code in this space is libmv: https://github.com/libmv/libmv.

libmv's codebase seems to be forked, with an earlier version at goggle code: http://code.google.com/p/libmv/ which also contains an interesting summary of other libraries in the 3D reconstruction space. Blender also has its own fork, which it uses for matchmoving, which is the integration of animated objects into a real world scene.

In turn, libmv seems be be influenced by the work of Marc Pollefeys? The tutorial is a readable summary of how to go from a collection of 2D images to a 3D model.

http://www.cs.unc.edu/~marc/research.html

http://www.cs.unc.edu/~marc/tutorial/

http://www.cs.unc.edu/~marc/tutorial.pdf

Question: Can a knowledgeable person here suggest which codebase is the best to start experimenting with, to build an application that converts a 2D photo sequence into a dimensionally accurate 3D model?

Re: The new Photosynth

#66

Post by wahsd »

hypernion323 wrote: post #19
ForHackernews wrote: post #17

Glad to see they're still working on this. I remember seeing a demo of this some years back and being really impressed. A nice reminder that Microsoft really does have some great engineering talent and they can break new ground.

Microsoft is always doing incredible research, just depressing that it's rarely converted into a compelling consumer product.

Well, Ballmer's gone. So maybe they will figure out how to pull together their innovation. It is kind of deflating sometimes to realize that MS was doing something that they simply dropped the ball on. The smart phone is solidly one of those things. They dominated the PDA market prior to the iPhone coming out. All they had to do was put some focus towards it.

Re: The new Photosynth

#67

Post by apu »

femto wrote: post #65

Another bit of code in this space is libmv: https://github.com/libmv/libmv . libmv's codebase seems to be forked, with an earlier version at goggle code: http://code.google.com/p/libmv/ which also contains an interesting summary of other libraries in the 3D reconstruction space. Blender also has its own fork, which it uses for matchmoving, which is the integration of animated objects into a real world scene. In turn,…

Although I don't have first hand experience with the code, a former labmate of mine (I'm at the Univ. of Washington, and he's now at Google) is one of the leading experts on this area of research, and his VisualSFM [1] tool is, I think, the best and easiest-to-use available online.

Briefly, there are three main steps required to go from images to a 3d viewer like PhotoSynth:

1. Figure out where each image was shot from (the "camera pose") and get a sparse set of 3d points from the scene. These two are estimated simultaneously using bundle adjustment [2].

2. Go from a sparse set of 3d points to a dense 3d model. This is done using a technique called Multiple View Stereo (MVS), of which the leading (open) implementations are PMVS/CMVS [3,4].

3. Build an image-based rendering system that intelligently blends between the 3d models and images to minimize artifacts.

The VisualSFM software will do steps 1 and 2. Step 3 is still quite a challenging problem, but depending on what you're doing, you could use standard 3d modeling environments to look at your data.

[1] http://ccwu.me/vsfm/

[2] http://en.wikipedia.org/wiki/Bundle_adjustment

[3] http://www.di.ens.fr/pmvs/

[4] http://www.di.ens.fr/cmvs/

Re: The new Photosynth

#68

Post by mxfh »

seems a bit of a step back in possibilities, but with streamlined UI. With the old photosynth you could even extract the point clouds from a bunch of photos of a scene you uploaded.

http://binarymillenium.com/2008/08/exporting-point-clouds-fr...

http://synthexport.codeplex.com/

But making meaningful 3d triangulations out of point clouds is a whole other story.

The glitchy charme of the new pales to the wonder of seeing a explorable pointcloud created out of a pile of photos from Stonehenge.

http://photosynth.net/view.aspx?cid=e5c7e730-95a3-4a29-a38e-...

Re: The new Photosynth

#69

Post by AdamTReineke »

netrus wrote: post #5

If you didn't bother to read the "learn more": When in the viewer, press C to see the 3D interpretation of individual shots and M for a map of the path taken by the camera.

Controls in 3D mode: right-click and drag to move the camera, scroll to zoom. Arrow keys move the camera location.

Re: The new Photosynth

#70

Post by amelim »

femto wrote: post #65

Another bit of code in this space is libmv: https://github.com/libmv/libmv . libmv's codebase seems to be forked, with an earlier version at goggle code: http://code.google.com/p/libmv/ which also contains an interesting summary of other libraries in the 3D reconstruction space. Blender also has its own fork, which it uses for matchmoving, which is the integration of animated objects into a real world scene. In turn,…

Sure! My lab focuses on SLAM and 3D reconstruction, especially for robotic applications. We've developed a BSD-licensed C++ (w/ MATLAB wrapper) library with specific applications towards 3D reconstruction problems such as SLAM and structure from motion. It's called GTSAM [1]

We actively maintain and release new features as they are published. While we don't provide a full out of the box pipeline (yet!), there are plenty of examples and documentation which walk you though the math, implementation, and other issues. If you want to read about the graphical models underlying GTSAM, see [2]

Utilizing OpenCV for feature detection and association is pretty much all you really need to add to a program in order to recreate Photosynth using gtsam. I'd also you recommend KAZE features from a former post-doc out of our lab, it's state of the art and recently added OpenCV wrappers[3]. However, it's also trivial to integrate other sensors such as IMUs, GPS, lasers, etc. for full navigation problems.

If you wish to know more about the actual subject, I definitely recommend Hartley and Zisserman's Multiview Geometery Book[4]

[1] https://borg.cc.gatech.edu/borg/

[2] http://www.cc.gatech.edu/~dellaert/pub/Dellaert06ijrr.pdf

[3] https://github.com/pablofdezalc/akaze

[4] http://www.robots.ox.ac.uk/~vgg/hzbook/index.html

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