What key do I use to relate the medadata coordinates with a recording in a sig-set?
This part of the question addresses still images. For the sig-set file, the name attribute of the presentation element is matched to the recording_id attribute in the Recording element of the metadata file. For example, the metadata for the image referenced in from the sig-set would be matched to in the metadata file. 3D scans consist of two presentations (recordings). The attribute name associated with either presentation can be matched with the recording_id attribute. Yes, this means that the meta-data for each 3D scan is listed twice in the metadata file, once mapped to the texture channel and once mapped to the shape channel.
