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Topic: Larger synth

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JonCC4 (Over 1 year ago)
Is there likely to be a 64bit Windows Photosynth anytime soon?

Am particularly interested in building larger synths, and subsequently exceeding the current memory issues of 32bit application.

Has anyone had experience of the 64bit Linux version of the app and can it generate larger synths with more available memory?
Nathanael (Over 1 year ago)
How much RAM does your current machine have, Jon? 

When you are running a 32bit application in a 64bit operating system, the 32bit app can have up to 4GB of physical RAM if it has been programmed to take advantage of it (which I believe the synther has, based on the output of its log files). If your computer only has 4GB of physical RAM, however, then some of this will be under use by the operating system, system services, and any other open applications. I think that you probably need a machine with at least 6GB of RAM before you can claim that you've exhausted the limits of the 32bit synther.

When you are running a 64bit application in a 64bit operating system, the 64bit app can have up to 8TB of physical RAM, however the largest amount of RAM that I have heard of Microsoft or id Software installing is 192GB of RAM, so it will be a few more years before anyone exhausts the limits of 64bit computing.
Nathanael (Over 1 year ago)
There is no official 64bit Linux version of Photosynth, so I assume that you are talking about Noah Snavely's 'Bundler'. This has been ported to Windows several times as well, if you wish to use it, but it isn't quite as optimized for speed as Photosynth is.

You should be aware that one of Photosynth's tricks to match more photos together is to only use 1.5 megapixel versions of any photo that you give it for the matching process, so you may want to do the same with Bundler if you find that it is taking too long or running out of RAM. (Photosynth still uploads the full resolution images to the website, by the way. It only uses the lower resolutions for the image matching.)

Here's Henri Astre's Structure from Motion Toolkit, which contains Bundler (as well as PMVS) code: 
http://www.visual-experiments.com/demos/sfmtoolkit/

To my knowledge Henri's is the most updated, but also see Pierre Moulon's original Windows port and Josh Harle's photogrammetry toolkit.
Nathanael (Over 1 year ago)
Also visit the Photogrammetry Forum at http://pgrammetry.com for more help.

I'm not sure what your goal is for making larger synths - whether you're interested primarily in the point clouds from that or just more photography put together, but if it's the model that you're after, I was wondering if you had run across the work that people are doing on using cameras with depth sensors (like the Kinect) to do 3D scanning.

Here are three videos that show what I mean: 
http://www.youtube.com/watch?v=KJ6v37GypoE
http://www.youtube.com/watch?v=Cldf7UdFq1k
http://www.youtube.com/watch?v=quGhaggn3cQ

Getting back to if we can expect a 64bit version of the synther anytime soon, I'm inclined to say, 'No', based on what Drew Steedly said almost exactly three years ago in this video: http://channel9.msdn.com/blogs/nicfill/shutterspeed-ep04-the-photosynth-team

On the other hand, Photosynth team, if there's news on this, please do update me.
Nathanael (Over 1 year ago)
Oh... I just now looked at your profile and can only see one synth with 300 photos in it. If this is all that you have attempted, let me be the first to tell you that people have gotten close to 1,800 photos in a synth with the 32bit synther.

How fast you run out of memory seems to depend largely on how many of the photos share the same parts of the scene. What this means is that as long as you spread your photos out evenly over a space, it may take a long time to put the photos together, but you should be able to fit considerably more than 300 photos in a synth.

Related discussions, if you haven't already read them: 
http://photosynth.net/discussion.aspx?cat=ceca0f30-0f7c-4468-811a-32b623ea8563&dis=4e257d2c-bf39-44dc-8e81-4ec502ee1299
http://getsatisfaction.com/livelabs/topics/how_can_i_make_a_bigger_synth
http://www.pgrammetry.com/forum/viewtopic.php?f=10&t=174
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