1. A motion estimation computer to determine 3D modeling motion parameters, the motion estimation computer comprising: at least one processor; and a data storage to store determined 3D modeling motion parameters for video frames and to store instructions that when executed by the at least one processor cause the at least one processor to: simultaneously determine the 3D modeling motion parameters for video frames according to different first and second motion estimation techniques, wherein in response to detecting a failure of the first motion estimation technique for a current frame of the frames, the at least one processor is to re-determine, according to the first motion estimation technique, the 3D modeling motion parameters for the current frame from the motion parameters determined according to the second motion estimation technique for a previous frame of the frames or the current frame.