MATCH MOVING

In cinematography, match moving is a special effects technology to allow the insertion of virtual objects into real footage with the correct position, scale, orientation and motion in relation to the photographed objects in the scene. The term is used loosely to refer to several different ways of extracting motion information from a motion picture, particularly camera movement. Match moving is related to rotoscoping and photogrammetry. It is sometimes referred to as motion tracking.
Match moving is distinct from motion capture. The latter is a technology for recording the motion of objects, often human actors, in a controlled environment with special cameras and technology. The former is a software technique applied to normal footage that can be recorded in uncontrolled environments with ordinary cameras. This article defines match moving as the art of extracting motion information from actual footage, where additional cameras, motion capture sensors, and motion control photography are not necessarily used.
Match moving is primarily used to track the movement of a camera through a shot so that a virtual camera move can be reproduced by a computer system. The intent is that when the virtual and real scenes are composited together they will come from the same perspective and appear seamless.
The first step is identifying and tracking features. A feature is a specific point in the image that a tracking algorithm can lock onto and follow through multiple frames (SynthEyes calls them blips). Often features are selected because they are bright/dark spots, edges or corners depending on the particular tracking algorithm.