Elevation models for reproducible evaluation of terrain representation

Kennelly, Patrick; Patterson, Tom; Jenny, Bernhard; Huffman, Daniel P.; Marston, Brooke E.; Bell, Sarah Beth; Tait, Alex

doi:10.1080/15230406.2020.1830856

Cited by 17 publications

(8 citation statements)

References 68 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this paper, a previously U-Net network [28] was trained with the same training data set for 2000 epochs. Both the prior U-Net [28] and the adapted network proposed in this paper were used for shading with a multi-scale DEM [36]. Figures 10 and 11 show the shaded relief generated using the different networks and with a DEM of different cell sizes.…”

Section: Comparison With Other Methodsmentioning

confidence: 99%

Generation Method for Shaded Relief Based on Conditional Generative Adversarial Nets

Yin

et al. 2022

IJGI

View full text Add to dashboard Cite

Relief shading is the primary method for effectively representing three-dimensional terrain on a two-dimensional plane. Despite its expressiveness, manual relief shading is difficult and time-consuming. In contrast, although analytical relief shading is fast and efficient, the visual effect is quite different from that of manual relief shading due to the low degree of terrain generalisation, inability to adjust local illumination, and difficulty in exaggerating and selective representation. We introduce deep learning technology to propose a generation method for shaded relief based on conditional generative adversarial nets. This method takes the set of manual relief shading-digital elevation model (DEM) slices as a priori knowledge, optimises network parameters through a continuous game of “generation-discrimination”, and produces a shaded relief map of any region based on the DEM. Test results indicate that the proposed method retains the advantages of manual relief shading and can quickly generate shaded relief with quality and artistic style similar to those of manual shading. Compared with other networks, the shaded relief generated by the proposed method not only depicts the terrain clearly but also achieves a good generalisation effect. Moreover, through the use of an adversarial structure, the network demonstrates stronger cross-scale generation ability.

show abstract

Section: Comparison With Other Methodsmentioning

confidence: 99%

Generation Method for Shaded Relief Based on Conditional Generative Adversarial Nets

Yin

et al. 2022

IJGI

View full text Add to dashboard Cite

show abstract

“…Since the DEMs were created as data sources for constructing the graphical surface representation, they must have fine resolution, which is capable of representing abrupt changes in the terrain surface such as sharp ridges. Specifically, for printed maps that are worked with from a typical distance of 30 cm, the standard graphical quality of 0.1 mm must be ensured [48] (which, for example, means using a DEM of 50 m resolution is required for mapping at the 1:500,000 scale). For maps on computer screens, which are viewed from 2-3-times greater distances, a proportionally coarser resolution can be applied.…”

Section: Data Processing 421 Generation Of Reference Demsmentioning

confidence: 99%

Granularity of Digital Elevation Model and Optimal Level of Detail in Small-Scale Cartographic Relief Presentation

Samsonov

2022

Remote Sensing

View full text Add to dashboard Cite

One of the key applications of digital elevation models (DEMs) is cartographic relief presentation. DEMs are widely used in mapping, most commonly in the form of contours, hypsometric tints, and hill shading. Recent advancements in the coverage, quality, and resolution of global DEMs facilitate the overall improvement of the detail and reliability of terrain-related research. At the same time, geographic problem solving is conducted in a wide variety of scales, and the data used for mapping should have the corresponding level of detail. Specifically, at small scales, intensive generalization is needed, which is also true for elevation data. With the widespread accessibility of detailed DEMs, this principle is often violated, and the data are used for mapping at scales far smaller than what is appropriate. Small-scale relief shading obtained from fine-resolution DEMs is excessively detailed and brings an unclear representation of the Earth’s surface instead of emphasizing what is important at the scale of visualization. Existing coarse-resolution global DEMs do not resolve the issue, since they accumulate the maximum possible information in every pixel, and therefore also require reduction in detail to obtain a high-quality cartographic image. It is clear that guidelines and effective principles for DEM generalization at small scales are needed. Numerous algorithms have been developed for the generalization of elevation data represented either in gridded, contoured, or pointwise form. However, the answer to the most important question—When should we stop surface simplification?—remains unclear. Primitive error-based measures such as vertical distance are not effective for cartography, since they do not account for the landform structure of the surface perceived by the map reader. The current paper approached the problem by elaborating the granularity—a newly developed property of DEMs, which characterizes the typical size of a landform represented on the DEM surface. A methodology of estimating the granularity through a landform width measure was conceptualized and implemented as software. Using the developed program tools, the optimal granularity was statistically learned from DEMs reconstructed for multiple fragments of manually drawn 1:200,000, 1:500,000, and 1:1,000,000 topographic maps covering different relief types. It was shown that the relative granularity should be 5–6 mm at the mapping scale to achieve the clearness of relief presentation typical for manually drawn maps. We then demonstrate how the granularity measure can be used effectively as a constraint during DEM generalization. Experimental results on a combination of contours, hypsometric tints, and hill shading indicated clearly that the optimal level of detail in small-scale cartographic relief presentation can be achieved by DEM generalization constrained by granularity in combination with fine DEM resolution, which facilitates high-quality rendering.

show abstract

“…We downloaded the manual relief map from the Shaded Relief Archive (shadedreliefarchive.com/ Crater-Lake.html). The analytical relief layers (multidirectional and ray-traced) were derived from a 3.33-meter resolution DEM from a set of sample elevation models provided by Kennelly et al (2021), and the bathymetry was derived from a 1-meter ASCII XYZ grid re-sampled to 3.33 meters (pubs.usgs.gov/dds/dds-72/site/gridfaq. htm#getacopy).…”

Section: Sti Mu LImentioning

confidence: 99%

“…However, Raposo and Brewer (2014) found that map location and the types of landforms present in the stimuli played a significant role in readers' aesthetic preferences. Future research could involve showing participants maps of a variety of locations, such as in Jenny and Patterson (2021), manual relief from shadedreliefarchive.com, or using different landforms such as in Farmakis-Serebryakova and Hurni's (2020) experiment to either corroborate or challenge the findings of our exploratory research.…”

Section: M Itations An D Fu Rth Er Researchmentioning

confidence: 99%

That’s a Relief: Assessing Beauty, Realism, and Landform Clarity in Multilayer Terrain Maps

Douglass¹,

Fish²

2022

View full text Add to dashboard Cite

Terrain maps are often composed of shaded relief along with other raster layers which we call thematic terrain layers to create aesthetically pleasing and clear maps of physical geography. Despite that the interplay of layers is of primary concern to a cartographer, much of the research on terrain mapping has focused on studying terrain layers individually. This research aimed to fill this gap by evaluating the effect of combining shaded relief with thematic terrain layers and assessing ratings of beauty, realism, and landform clarity in an exploratory online user study. Specifically, we tested the combination of: manual, multidirectional, and ray-traced shaded relief with three thematic terrain layers: hypsometric tinting, land cover, and orthoimagery. There are five main findings from this exploratory study: (1) there was a direct correlation between beauty and realism scores, (2) the manual relief we tested was consistently rated lowest for beauty, realism, and landform clarity, and orthoimagery was rated the highest for beauty and realism, (3) shaded relief was more influential than thematic terrain layers on landform clarity ratings, (4) participant’s geographic familiarity had a significant impact in four specific instances of the user study, and (5) neither shaded relief or thematic terrain layers were the sole contributors to map reader perceptions of beauty, realism, or landform clarity. We conclude by identifying limitations in our stimuli design and presenting ideas for future research studies on terrain design.

show abstract

Elevation models for reproducible evaluation of terrain representation

Cited by 17 publications

References 68 publications

Generation Method for Shaded Relief Based on Conditional Generative Adversarial Nets

Generation Method for Shaded Relief Based on Conditional Generative Adversarial Nets

Granularity of Digital Elevation Model and Optimal Level of Detail in Small-Scale Cartographic Relief Presentation

That’s a Relief: Assessing Beauty, Realism, and Landform Clarity in Multilayer Terrain Maps

Contact Info

Product

Resources

About