About a year ago I wrote about the Photosynth technology from Microsoft that creates 3D spaces from collections of photographs. At the time it only worked with a few sample data sets created by Microsoft, but there was a very nice demo to download and it was a pretty exciting piece of tech. Just a few days ago Microsoft released a full version that allows you to create your own “photosynths” by uploading collections of photos.
I just had to have a go. The image above shows a screen-grab of the Photosynth viewer with some data that I took.
Read on for more on the new release, how I got on with it, videos and links to the 3D scenes that I created.
It may be worth reading my original posting for a description of what Photosynth does, but in a nutshell it attempts to make a 3D spatial model by matching up lots of photos of the same subject taken from different viewpoints. What Microsoft has just released is a new version that can take your own photos, a website to host these, and plugins for Internet Explorer and Firefox to view the scenes in 3D. You get all you need from photosynth.net.
When you get to this site you get three things:
- A plugin for your web browser just for viewing photosynths.
- An application to install on your computer that will process and upload your own photos to create a photosynth.
- A brief “how-to” guide in PDF form that tells you how to go about taking photos to make good photosynths. There is an online video too, but to date I have not watched it.
The first two are wrapped up in the same installation packet. You will need a WindowsLive ID or MSN Messenger account to use the latter, but you don’t need to create an account if you just want to view other people’s work. Also note that the application and, I think, the viewing plugins are Windows only so Mac users are out of luck.
If you have had the earlier demo version of the viewer installed on your machine, then either uninstall or disable the original plugin. In Firefox I had the problem that it failed to recognise I had the viewer installed, and I think it was getting confused with the two plugins there. Once I disabled the old one everything worked fine.
Browse the existing photosynths to get a good feeling for it – I would recommend only choosing those that have been marked at or near “100% synthy”. If not, then things look very boring indeed. The user interface is quite intuitive, and you certainly don’t need to read a manual to use the basic navigation features.
I went out to our local church that this weekend was having its annual Flower Festival. This gave me the opportunity to wander around both inside and outside snapping away lots of shots to use with Photosynth. The following video shows the results when uploaded and processed by Photosynth, and put into “play” mode (which moves the viewpoint around the scene between camera viewpoints).
The scene was reconstructed fom just 35 photos. It was incredibly easy to do – just point the Photosynth application at the images, press “upload”, and then wait. Once complete you are given the option of viewing the result immediately in your browser. Part way through the video I used the “p” key option to toggle the display of the point cloud that Photosythc has calculated that represents the 3D information extracted from the photos. Normally this is obscured as the photos are shown by default, but as you can see it has done a fine job of picking out the shape of the church building. The following two stills show the default scene, and then with point cloud display turned on.
Of course, viewing this as a video does not do Photosynth justice. Once you have the viewer installed, then jump straight to this dataset using this link (note, will open in new window/tab).
And the final bit of niceness is that you can also geo-locate your photosynth from within the viewer, assuming you are logged in as the creator of the scene. This uses Virtual Earth as its back-end, and is very easy to do.
Taking photos to make nice 3D spaces is pretty straghtforward – the short guide on the Photosynth website is worth a read. The main rule is to ensure lots of overlap between images, as this gives the software something to use to help work out areas of similarity. For the church shoots I just wandered around with my digital SLR on medium resolution mode (2.4k x 1.6k pixels) and storing as JPEG. There is really no point in using RAW for this, and picking a lower resolution image saves on upload time. I think even the res I used is higher than is needed.
I also took about 30 interior shots, and I was very pleased with the results. The video below shows it running live. You can also see the actual Photosynth at this link here.
The videos were captured using the excellent free CamStudio application.
I think Photosynth is quite simply awesome. I highly recommend at least viewing some of the content created using the system. And creating them yourself is so easy you may as well have a go.