Thank you for the reply, Andreas.
Sorry for the confusion, but no - the videos were recorded in a custom fashion using opencv and do not have the .oni extension. I don't think they will contain the same framewise listing of the parameters but they will contain the exact "depthFrame.data()" from when the frame came from a camera stream.
Do you know of a way to essentially replace the StreamReader with frames streamed from the saved video? I will look into the cpp-source of viewer for further inspiration.