--parallel_epipolar
--ba sba

BTW those options should be passed as command arguments to bundler.exe directly (and not been added to the options.txt file).

The parallel_epipolar option allows to estimate the fundamental matrices (ransac + lm) in parallel. This problem is embarrassingly parallel but due to some global variables used in the callback passed to lmfit it wasn’t that easy to implement: I’ve used a functor to hide the global variables used by the callback but sadly lmfit doesn’t have a void* userData parameter (only a pointer to the callback). Thus I’ve modified lmfit and add this missing parameter that allow me to pass a pointer to my functor. Furthermore I had to compile almost everything in C++ instead of C to use my functor inside lmfit. Thus I had to fix a lot of malloc calls that weren’t compiling in C++ due to missing cast. To keep a “backward behavior compatibility” this option is disabled by default.

The ba option allows to change the bundle adjustment “engine” used. Here is the list of available “engine”:

• sba (default)
• none (for debug only)
• pba_cpu_double
• pba_cpu_float
• pba_gpu_float

Pba stand for Parallel Bundle Adjustment: I’ve integrated mcba from Changchang Wu.

So if you have an Nvidia GPU card and installed the Cuda runtime you can add those options:

bundler.exe list_focal_absolute.txt --ba pba_gpu_float --parallel_epipolar
--options_file options.txt //on the same line

Timing on a 245 pictures dataset:

You can download this new version of bundler: bundler-multiBA-parallelEpipolar-x64.zip
Update: the source code is available on the MCBA branch of my Bundler fork.

Nghiaho optimizations are disabled by default as I’ve found that it generates a point cloud less dense. You can enable the optimization by adding:

--optimize

as last PMVS2.exe parameter in your command prompt or just activate the optimization by modifying the following files:

• 3 – Prepare for PMVS2.wsf line 49 -> var USE_OPTIMIZED_PMVS = true;
• 4 – Prepare for CMVS.wsf line 46 -> var USE_OPTIMIZED_PMVS = true;

You can download PhotoSynthToolkit11.zip.

This version introduce a new feature that will allow you to process a PhotoSynth without needing to wait for the end of the upload. In fact you can even cancel your synth as soon as the computation is complete. But be aware that all pictures uploaded in the meantime will stay on photosynth server (AFAIK).

How to proceed:
- wait for synth to be processed (but not fully uploaded).
- copy the 2 following files from %temp%\Photosynther to another folder (d:\my_synth for example)

• collection.dzcz
• collection.synth.bin

- then you can launch the step 1 of the PhotoSynthToolkit by providing your folder (d:\my_synth).
- you’ll need then to copy your original jpegs to the distort folder and you’re done!

You can download PhotoSynthToolkit10.zip.

• CMVS support finally integrated
• proper handling of folder with white space

How to use CMVS with PhotoSynthToolkit:

1. As usual run step 1 and move pictures from “hd” to “distort” folder.
2. You need to run first “Prepare for PMVS2″ then do NOT launch the generated bat file.
3. You can run “Prepare for CMVS” and run the generated bat file.

Warning: I’ve fixed all my programs to handle folder with white space (thanks to boost::filesystem). Sadly PMVS2/CMVS don’t handle them. The fix is trivial but instead of recompiling a new version I’ve found a bad workaround. I’m creating a temporary virtual drive z: pointing to your synth folder during the execution of PMVS2/CMVS using SUBST. The downside are that if you already have a z: drive it won’t work and if you kill PMVS2/CMVS you’ll have to manually remove the z: drive. To remove the z: drive type “subst z: /d” in your console.

If you need XSI/3DS max integration you’ll have to use the old version: PhotoSynthToolkit7.zip otherwise PhotoSynthToolkit9.zip is the latest version.

New feature coming:

• CMVS support (coming very soon)
• White space handling in the toolkit scripting (PhotoSynthGrabber is already ready)
• Expose HTTP Proxy parameters for the downloader

You can download the new version: PhotoSynthToolkit8.zip or keep the previous one in case you miss some advanced feature (vis.dat generation, SoftImage XSI / 3DS Max scripting for example): PhotoSynthToolkit7.zip.

I’m working on the development of a calibration system (like bundler) at Acute3D. I’ve decided to work with them as I think that they do have the best technology available and I wanted to work with very skilled people working in computer vision.

I don’t know if I’ll be able to continue writing on this blog as this new job is really more interesting and challenging for me.

The principle is very simple: the user drag and drop an unknown picture on the webpage. The picture is resized on the client side using canvas and then sent to the webservice using a classic POST Ajax call with the picture sent in jpeg base64. Then the pose estimator web service try to compute the pose and send an xml response. Then the pose is applied to the Three.js camera used in my PhotoSynth viewer.

I have cheated a little as I’ve used shots of a video with known intrinsic parameters. But I’ve two options to handle really unknown pictures:

• If the jpeg as Exif I can use it to find the focal (using a CCD database and a JS Exif parser)
• Otherwise I am planning to implement this in C++

I hope you enjoy this demo as much as I do and that Google and Microsoft are working in that direction too (especially Microsoft with Read/Write World…)

You can download the new Google Chrome extension from the chrome web store: Three.js Google Chrome extension. The old one is still available but this is not a good idea to have both activated at the same time… Do not hesitate to use the donate button (located in the right side-panel) if you find this extension useful… thanks!

Warning: this extension may use a lot of ram (point cloud are store in memory as regular js array not TypedArray).

Possible improvement

• Add picture thumbnails in the 3d environment (may become impossible without Microsoft adding CORS to the jpeg due to WebGL security issue)
• Add a free flight camera (easy to add but harder without roll: I’ve added features to Three.js Quaternion class for this purpose, but still not ready)
• Make the download point cloud link work! This is not my fault (I hope) I think that this is a Chrome bug. The only workaround that I can think of (without being sure that it would work) for this issue would be that Microsoft host downloadify.swf on photosynth.net… please ask them to do that!
• Add a Meshlab like camera system (mouse handling + white sphere): if you know Three.js please give it a try!

Credits

Please take a look at the list of all dependencies used for this demo in my previous post describing this PhotoSynth viewer.

The only trouble with this demo is that it is using a proxy PHP page to bypass ajax cross-domain security issue. Thus I won’t put it online (as it would kill my bandwidth limit). But I’ll try to update my Google Chrome extension so that you can give it a try too (will take time and I’m going in holiday…sorry).

On the tech side, this demo is using:

• Three.js: for the rendering
• Downloadify: to allow downloading PLY generated on the client-side
• jDataView: to parse binary xhr response
• ImageFlow: coverflow system
• Accordion(except css) + Tween + SynthParser created by me

Other news

On another side I’ve been up to:

• compile a bundler version with PBA support (with bad result: fast BA but erroneous point cloud)
• create a new framework for fast matching: already 3x faster than OpenSynther (which is already really fast). This new framework is compatible with multi-gpu and multi-cpu + you can add constraints to memory usage!
• create an hybrid AR solution for my current work based on my panorama tracking demo and using gyroscope information to fix the computing time of the vision part

1. Creating Synth: http://vimeo.com/14796939.
2. Downloading and Viewing: http://vimeo.com/25072862.
3. Viewing, Dense Reconstruction: http://vimeo.com/25071703.
4. Meshing model, creating texture: http://vimeo.com/25071366.
5. Projecting Hi-Res Images: http://vimeo.com/25072168.

I’ve also added the video tutorials links on the PhotoSynthToolkit page.

You can thank him on the pgrammetry forum: see Josh Harle announcement.

Thanks Josh!