ACM Trans. Graphics (SIGGRAPH), 32(4), 2013.
Representation for seamlessly looping video with controllable level of dynamism.
Abstract: Given a short video we create a representation that captures a spectrum of looping videos with varying levels of dynamism, ranging from a static image to a highly animated loop. In such a progressively dynamic video, scene liveliness can be adjusted interactively using a slider control. Applications include background images and slideshows, where the desired level of activity may depend on personal taste or mood. The representation also provides a segmentation of the scene into independently looping regions, enabling interactive local adjustment over dynamism. For a landscape scene, this control might correspond to selective animation and deanimation of grass motion, water ripples, and swaying trees. Converting arbitrary video to looping content is a challenging research problem. Unlike prior work, we explore an optimization in which each pixel automatically determines its own looping period. The resulting nested segmentation of static and dynamic scene regions forms an extremely compact representation.
Hindsight: The time-mapping formula (1) in the paper actually has a much simpler expression: \phi(x,t) = s_x + ((t - s_x) \mod p_x). (One has to be careful that the C/C++ remainder operator "%" is not exactly the modulo operator.)
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