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Topic: Downloading Synth to HardDrive

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R.B (Over 1 year ago)
Hi,
I created a synth using certain images .Now I want to download and save the gigapixel image formed as a jpeg to my Hard disk so that I can use it for other processing.How do I do this?(Infact I did check related posts but could not find an answer )
-Thanks,
R.B (Over 1 year ago)
I did see a related post but I am sorry I could not get how to go about it .
Nathanael (Over 1 year ago)
Hi there, R.B, 

There is a distinction that I think should be made here. Photosynth.net currently stores two very different sorts of imagery: photosynths and panoramas.

Photosynths are created by the Photosynth app for Windows and their strong suit is correctly positioning photos that are taken of a subject from all sorts of different positions. When the synth is complete, the photos are all still separate.

The panoramas which you see here on Photosynth.net are created with the Image Composite Editor app from Microsoft Research (download it here: http://bit.ly/microsoftice ) and its strong suit is stitching multiple photos which have been taken from the same position into one single image. If you use Image Composite Editor to stitch a panorama of your photos, you will have the option to either save it to your hard drive in a number of different formats for further processing or to publish it to Photosynth.net if you prefer to share it easily with others.
Nathanael (Over 1 year ago)
Panorama stitchers have been around for some time now, but they are limited to stitching photos that are all taken from the same perspective and they are really only stitching in 2D. There is a limited sense in which a 360 degree panorama is 3D because it wraps all the way around you, but even if you use a special panoramic tripod that takes photos looking in all directions from a single point in the air, the most 3D that a panorama will ever be is a spherical bubble of photography. It is still beautiful and easy to use, but it really isn't what I would call 3D and changing the camera's perspective will most likely result in stitching errors.
Nathanael (Over 1 year ago)
What systems like Photosynth's synther do is to actually use the differences in camera positions to start figuring out how far different parts of the scene were from the camera and what their distances are, relative to each other. 

Depending on how few the camera perspectives there are or how far between they are, Photosynth will be able to calculate different amounts of the photographical content. The parts which it believes to be correct are called the 'point cloud'. If you look at a synth like this one and look at its point cloud, you can see that it creates something that no panorama stitcher does:
http://photosynth.net/view.aspx?cid=ba12ab48-6899-4d7f-b28c-624f5f7ff4f0

For Windows users who have the Photosynth app installed, I recommend the older viewer. It's missing a few features like highlights and overhead view, but it's much faster: 
http://photosynth.net/d3d/photosynth.aspx?cid=ba12ab48-6899-4d7f-b28c-624f5f7ff4f0
Nathanael (Over 1 year ago)
Research is ongoing in the Computer Vision field and there are certainly ways to get more detail than what we see in Photosynth's point clouds, which are referred to as a 'sparse reconstruction'.

Once a tool such as Photosynth has solved for all of the camera positions for a synth, other programs can be used to perform multi-view stereo, inverse ray-tracing, etc. to obtain a dense reconstruction of the content of the photos. This can certainly be thought of as the growth of panorama stitching into the third dimension.

For the time being, Photosynth's focus with synths is using that sparse reconstruction as a means of organizing the actual original photos in 3D space and allowing people to quickly and smoothly download only the detail in the photos which currently fits on their screen as they zoom in. 

I hope that clarifies the differences between photosynths and panoramas for you. In your case, I believe that using ICE would give you exactly what you're after.
R.B (Over 1 year ago)
Thanks a lot Nathanael for a really elaborate explanation !I am now using ICE to stitch some Gigapixel images.Aim of our project is to do 3D reconstruction given gigapixel images from certain viewpoints. :)
Nathanael (Over 1 year ago)
Sounds like I overexplained things. ツ

I'd love to see your results when they're ready to be seen.
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