Journal of Geographical Sciences

图/表详细信息

Structured representation and compression method of viewshed: An example analysis of communication viewshed

WANG Yiwen, ZHU Jun, DOU Wanfeng

地理学报(英文版), 2026, 36(5): 1299-1320. DOI: 10.1007/s11442-026-2493-x

Method	Type	Compression ratio
Proposed (Structured)	lossy	407
JPEG2000	lossy	64
SPIHT	lossy	70
Quadtree	lossy	55

Table 7 Compression ratios for each method on a 500×500 terrain

本文的其它图/表

Figure 1 Overall framework of the communication viewshed structured representation method
Figure 2 Schematic diagrams of the terrain and communication viewshed for the base station at three different terrain points (the red part of each figure indicates that the communication quality is close to 1 and is good, whereas the blue part indicates that the communication quality is close to 0 and is poor.)
Figure 3 Sensitivity of regional communication quality to the binarization threshold T
Figure 4 Comparison of the communication viewshed before and after threshold division (the black area in (b) indicates good communication quality, whereas the white area indicates poor communication quality.)
Figure 5 Schematic diagram of gaps in the communication viewshed (the fuzzy boundaries of the spatially aggregated regions in this communication viewshed lead to a reduction in the accuracy of feature extraction.)
Figure 6 Structured representation template of the communication viewshed of a single base station
Figure 7 Terrain diagram for the experiment
Figure 8 Schematic diagrams of the communication viewsheds of base stations at three terrain points
Figure 9 Schematic diagrams of the regional division of the communication viewsheds of three base stations during feature extraction
Figure 10 Results of analyzing the structured representations of the communication viewsheds of the three base stations and translating the analytic content into graphs
Figure 11 Topographic map of the North District of Nanjing Normal University (a) and signal coverage demand area (b)
Figure 12 Schematic diagrams of the communication viewsheds of the top four base stations in terms of the matching score ranking and the regional division results obtained via feature extraction (the color bar in the figure represents the communication quality.)
Table 1 Index values and matching degree values of the top four base stations in terms of matching scores
Table 2 Computation times of two algorithms for solving a single-base-station location problem
Figure 13 Comparison of the spatial distribution of the communication viewshed as reflected by the parameters in the structured representation
Table 3 Parameters of each area covered by the base station at (200, 200)
Table 4 Error of contour fitting for each region when a structured representation is used
Table 5 Average relative error of the communication quality values for each region when structured expressed
Table 6 Comparison of space occupied when communication viewshed data on terrains of different sizes are stored in various forms
Figure 14 Compression ratios of the two different compression methods for terrains of different sizes

模态框（Modal）标题

图/表 详细信息

图/表详细信息