A Uniform Sky Illumination Model to Enhance Shading of Terrain and Urban Areas

Kennelly, Patrick; Stewart, A. James

doi:10.1559/152304006777323118

Cited by 28 publications

(19 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The shortcomings of relief shading are successfully addressed by diffuse illumination relief shading models, such as a uniform sky illumination (Kennelly and Stewart, 2006) and sky view factor (SVF; Zak sek et al, 2011). Both have been successfully applied in archaeology ( Stular, 2011;Kokalj et al, 2011), with the latter having a significant advantage because it is much faster to calculate and accessible as a free tool (ZRC SAZU, 2010).…”

Section: Relief Shading and Relief Illumination Methodsmentioning

confidence: 99%

Visualization of lidar-derived relief models for detection of archaeological features

Štular

Kokalj

Oštir

et al. 2012

Journal of Archaeological Science

150

View full text Add to dashboard Cite

Section: Relief Shading and Relief Illumination Methodsmentioning

confidence: 99%

Visualization of lidar-derived relief models for detection of archaeological features

Štular

Kokalj

Oštir

et al. 2012

Journal of Archaeological Science

150

View full text Add to dashboard Cite

“…In the published article, the authors focused on the interpretation of the basic relief features and did not elaborate the physical background and the optimal visualization parameters. Kennelly and Stewart [30] showed that using a uniform sky illumination enhances the perception of the relative height of surface elements.…”

Section: Relief Shadingmentioning

confidence: 99%

Sky-View Factor as a Relief Visualization Technique

2011

View full text Add to dashboard Cite

Abstract:Remote sensing has become the most important data source for the digital elevation model (DEM) generation. DEM analyses can be applied in various fields and many of them require appropriate DEM visualization support. Analytical hill-shading is the most frequently used relief visualization technique. Although widely accepted, this method has two major drawbacks: identifying details in deep shades and inability to properly represent linear features lying parallel to the light beam. Several authors have tried to overcome these limitations by changing the position of the light source or by filtering. This paper proposes a new relief visualization technique based on diffuse, rather than direct, illumination. It utilizes the sky-view factor-a parameter corresponding to the portion of visible sky limited by relief. Sky-view factor can be used as a general relief visualization technique to show relief characteristics. In particular, we show that this visualization is a very useful tool in archaeology as it improves the recognition of small scale features from high resolution DEMs.

show abstract

“…This numerical model of landform is increasingly considered as a wealth of morphometric information from a quantitative or qualitative point of view (Iwahashi et al 2001;Li et al 2005;Iwahashi and Pike 2007;Ferraris et al 2012;Karátson et al 2012). Notwithstanding the time consuming and tedious digitizing, the results provide an acceptable model of local landform and a more detailed Thereby, a 10-m-grid DEM of Teboursouk region was produced and a model of shaded relief map was extracted using GIS spatial analysis approach and the hill (or oblique) shading method (Li et al 2005;Kennelly and Stewart 2006). The generated illumination model is important in geomorphology and morphostructural mapping to create realistic surface renderings (Fig.…”

Section: Data Source and Drainage Hierarchizationmentioning

confidence: 99%

Morphotectonic and Morphodynamic investigations revealed by isobase surfaces analysis and derived differential mapping using GIS, Teboursouk area, northern Tunisia

Slama

Deffontaines²,

Turki

2015

Earth Sci Inform

View full text Add to dashboard Cite

Teboursouk area within the northern Tunisian Atlas presents a complex and heterogeneous geological framework leading to various geomorphic landforms among them there are numerous Triassic salt extrusions having an evident impact on the topographic configuration, shaping and dynamics. Landforms characterization of the study area, by morphostructural and morphodynamic mapping, was carried out using the isobase approach which is mainly based on the construction of topographic base-level surface from each channel order. GIS environment and spatial data analysis tools have been used to perform this procedure using 10 m-grid DEM and digitized drainage network at a semi-detailed scale (1: 50 000). The analysis included the creation of isobase maps of 2nd, 3rd and 4th-order channels. Grid calculations allowed the construction of (1) a combined surface from 2nd and 3rd order and (2) a differential map which represents the topographic residual between present day surface (original DEM) and isobase of 4th order. In fact, qualitative analysis of different isobase surfaces shows a good delimitation of most morphostructures and highlights a model of an atypical morphostructure concerning the Triassic extrusion of Jebel ech Cheid (JEC). Isoline anomalies and disturbances have indicated that major morphotectonic lineaments, interpreted as fractures, trend NE-SW to NNE-SSW adapting to the regional strike-slip fault system in response to NW-SE late Alpine transpressive tectonics. Several isoline inflexions were, however, well correlated with observed tectonic fractures and some of them are considered to be closely related to basement as the 4th-order analysis demonstrates. In contrast, neotectonic features, active landforms and lineaments were quantitatively described and localized based on the differential mapping approach.

show abstract

A Uniform Sky Illumination Model to Enhance Shading of Terrain and Urban Areas

Cited by 28 publications

References 16 publications

Visualization of lidar-derived relief models for detection of archaeological features

Visualization of lidar-derived relief models for detection of archaeological features

Sky-View Factor as a Relief Visualization Technique

Morphotectonic and Morphodynamic investigations revealed by isobase surfaces analysis and derived differential mapping using GIS, Teboursouk area, northern Tunisia

Contact Info

Product

Resources

About