1. A motion estimation computer to determine 3D modeling motion parameters, the motion estimation computer comprising: at least one processor to: simultaneously determine 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; and a data storage to store the determined 3D modeling motion parameters.