ABSTRACT
Video fusion aims to synthesize video footage from different sources into a unified, coherent output. It plays a key role in areas such as video editing and special effects production. The challenge is to ensure the quality and naturalness of synthetic video, especially when dealing with footage of different sources and qualities. Researchers continue to strive to optimize algorithms to adapt to a variety of complex application scenarios and improve the effectiveness and applicability of video fusion. We introduce an algorithm based on a convolution pyramid and propose a 3D video fusion algorithm that looks for the potential function closest to the gradient field in the least square sense. The 3D Poisson equation is solved to realize seamless video editing. This algorithm uses a multi-scale method and wavelet transform to approximate linear time. Through numerical optimization, a small core is designed to deal with large target filters, and multi-scale transformation analysis and synthesis are realized. In terms of seamless video fusion, it shows better performance than existing algorithms. Compared with editing multiple 2D images into video after Poisson fusion, the video quality produced by this method is very close, and the computing speed of the video fusion is improved to a certain extent.
ABSTRACT
Van der Waals (vdW) assembly of low-dimensional materials has proven the capability of creating structures with on-demand properties. It is predicted that the vdW encapsulation can induce a local high-pressure of a few GPa, which will strongly modify the structure and property of trapped materials. Here, we report on the structural collapse of carbon nanotubes (CNTs) induced by the vdW encapsulation. By simply covering CNTs with a hexagonal boron nitride flake, most of the CNTs (≈77%) convert from a tubular structure to a collapsed flat structure. Regardless of their original diameters, all the collapsed CNTs exhibit a uniform height of ≈0.7 nm, which is roughly the thickness of bilayer graphene. Such structural collapse is further confirmed by Raman spectroscopy, which shows a prominent broadening and blue shift in the Raman G-peak. The vdW encapsulation-induced collapse of CNTs is fully captured by molecular dynamics simulations of the local vdW pressure. Further near-field optical characterization reveals a metal-semiconductor transition in accompany with the CNT structural collapse. Our study provides not only a convenient approach to generate local high-pressure for fundamental research, but also a collapsed-CNT semiconductor for nanoelectronic applications.