:In the application of remote sensing image fusion based on wavelet packet, the wavelet packet frequency shifting algorithm used to adjust the frequency sequence of wavelet packet decomposition is introduced to solve the frequency aliasing phenomenon caused by interval sampling. The roofs of ancient residential buildings in northern Jiangsu have a unique art. Features: Discusses the roof decoration art of residential buildings in northern Jiangsu, aiming to provide some references for modern architecture. It shows that the roofs of residential buildings are deeply influenced by the land culture and marine culture, and have both normative, delicate and exaggerated factors. . The roof ridge of the folk houses embodies the uniqueness and rich connotation of Nantong culture, and we need to actively explore the beneficial elements in it. By examining the overall trend of international computer-assisted language testing research, high-yielding countries, authors, institutions and high-cited journals, research hotspots and high-innovation literature.