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No Metadata Tutorial
Building a model without any metadata results in model with no scale or location. The SFM algorithm will create camera models centered at latitude and longitude: (0, 0). The model is also in an arbitrary unit-less scale, making it appear much smaller than it really is. Once the model is created, it can be georegistered, which will also set the scale correctly.
To start a no metadata upload, upload a new dataset and choose "No Metadata" for the Metadata Type. For this tutorial, use the same https://vsi-ri.com/data/downtown_providence.zip providence data, only this time do not upload the cameras and name it "No Meta Providence"
Once the files have been uploaded and processed, run SFM processing on them. Upon successful SFM processing, the cameras have been registered.
In order to get a feeling for the cameras, you can use the Image Viewer to look at the cameras.
You will see two sets of cameras in the Tie Point editor now, first the original "No Meta Providence" cameras, which are all at 0,0 pointing straight down.
Note In order to see the cameras in Ceisum, you much click the Imagery Icon in the top right corner of Cesium, and scroll down to the bottom and choose the WGS84 Ellipsoid. This will move the surface model so that you can see the cameras now.
Upon clicking on a camera to zoom in on, you will see all the cameras are pointing straight down, and are all on top of each other at the same coordinate, 0,0
images/no_meta_initial_cameras.png
Now, open up the Image Sets slide out again, and select the "SFM No Meta Providence Image Sequence" Camera Set. Now you can see that the SFM algorithm has positioned and oriented the camera from the no metadata sequence.
Next, create some control points and tie points and run the Camera Georegistration Tutorial.
Now you can run apps like the error analysis on the no metadata data set that you could run only run on full metadata cases.