Video composition methods and their semantics

A comparison is made of four modular composition methods suitable for pipeline architectures, including object-based and pel-based composition methods with absolute or relative ordering. For each composition method, it is shown what it does, what it means physically, and thus what limitation it imposes. The conclusion is that the object-based methods, although more efficient to describe video composition, are not completely general. A method is proposed to extend the generality of object-based composition while also retaining its efficiency in describing video composition.<
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