MULTISPECTRAL ANALYSIS OF INDIGENOUS ROCK ART USING TERRESTRIAL LASER SCANNING

Multispectral analysis is a widely used technique in the photogrammetric and remote sensing industry. The use of Terrestrial Laser Scanning (TLS) in combination with imagery is becoming increasingly common, with its applications spreading to a wider range of fields. Both systems benefit from being a non-contact technique that can be used to accurately capture data regarding the target surface. Although multispectral analysis is actively performed within the spatial sciences field, its extent of application within an archaeological context has been limited. This study effectively aims to apply the multispectral techniques commonly used, to a remote Indigenous site that contains an extensive gallery of aging rock art. The ultimate goal for this research is the development of a systematic procedure that could be applied to numerous similar sites for the purpose of heritage preservation and research. The study consisted of extensive data capture of the rock art gallery using two different TLS systems and a digital SLR camera. The data was combined into a common 2D reference frame that allowed for standard image processing to be applied. An unsupervised k-means classifier was applied to the multiband images to detect the different types of rock art present. The result was unsatisfactory as the subsequent classification accuracy was relatively low. The procedure and technique does however show potential and further testing with different classification algorithms could possibly improve the result significantly.

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Educational course "Creation of virtual geological outcrops of the outskirts of Lviv"

10.5194/egusphere-egu21-4565 ◽

2021 ◽

Author(s):

Ihor Bubniak ◽

Serhiy Tsikhon ◽

Anatoliy Tserklevych ◽

Yevheniy Shylo ◽

Mariia Oliinyk

Keyword(s):

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Field Work ◽

Geological Structure ◽

The Third ◽

Self Study ◽

Different Types ◽

Teaching Award ◽

The City ◽

Educational Course

We present a new educational course "Creation of virtual geological outcrops of the outskirts of Lviv" for students of geological specialties. Discipline "Creation of virtual geological outcrops of the outskirts of Lviv" is a selective discipline for students of 2-3 courses of various specialties, which is lectured in the amount of 3 credits (according to ECTS). The course is 32 hours of classroom classes, 16 hours of these of lectures, the rest 16 hours of practical classes and 58 hours of self-study.The course is in three parts. First is preparatory ones. Students get acquainted with the geological structure of Lviv, prepare equipment for field work.The field stage (the second part of the course) includes the survey of 3-4 geological objects around Lviv. These can be natural outcrops, quarries. A particularly valuable object for learning is the Honey Cave, located within the city limits. Depending on the object, we choose the type of survey&#8212; digital photogrammetry or terrestrial laser scanning. Each group of 4 students explores 2 objects.The third cameral period includes field data processing. Students create 3D geological models and perform various measurements on them. Students compare different types of models to choose the best one. At this stage, students use a variety of software available in institutions. The final stage of the course is the preparation of a report and passing the exam.The project war partly financed by EGU HE Teaching Award.

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Intensity Values of Terrestrial Laser Scans Reveal Hidden Black Rock Art Pigment

Remote Sensing ◽

10.3390/rs13071357 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1357

Author(s):

Andrea Jalandoni ◽

W. Ross Winans ◽

Mark D. Willis

Keyword(s):

Southeast Asia ◽

Laser Scanning ◽

Rock Art ◽

Terrestrial Laser Scanning ◽

New Method ◽

Black Pigment

The intensity values of terrestrial laser scanning (TLS) can be used to reveal painted black rock art behind graffiti and moss. The effect was observed in Gumahon cave in Peñablanca, Philippines where previously unnoticed black pigment was exposed underneath moss, red and white painted graffiti, and etched name graffiti. The application of TLS intensity values for this purpose has not, to our knowledge, been previously reported. The significance of this finding is that archaeologists are provided a new method of detecting obfuscated rock art that can aid interpretation. The method can be applied in similar contexts as black painted rock art is common in limestone caves across Southeast Asia and Micronesia, but also ubiquitous globally.

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ANALYSIS OF FILTERING TECHNIQUES FOR INVESTIGATING LANDSLIDE-INDUCED TOPOGRAPHIC CHANGES IN THE OETZ VALLEY (TYROL, AUSTRIA)

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-v-2-2020-719-2020 ◽

2020 ◽

Vol V-2-2020 ◽

pp. 719-726

Author(s):

I. Gutierrez ◽

E. Før Gjermundsen ◽

W. D. Harcourt ◽

M. Kuschnerus ◽

F. Tonion ◽

...

Keyword(s):

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Classification Algorithms ◽

Rough Terrain ◽

Volume Changes ◽

Mountain Areas ◽

3D Point Clouds ◽

Filtering Technique ◽

Optimal Set

Abstract. Landslides endanger settlements and infrastructure in mountain areas across the world. Monitoring of landslides is therefore essential in order to understand and possibly predict their behavior and potential danger. Terrestrial laser scanning has proven to be a successful tool in the assessment of changes on landslide surfaces due to its high resolution and accuracy. However, it is necessary to classify the 3D point clouds into vegetation and bare-earth points using filtering algorithms so that changes caused by landslide activity can be quantified. For this study, three classification algorithms are compared on an exemplary landslide study site in the Oetz valley in Tyrol, Austria. An optimal set of parameters is derived for each algorithm and their performances are evaluated using different metrics. The volume changes on the study site between the years 2017 and 2019 are compared after the application of each algorithm. The results show that (i) the tested filter techniques perform differently, (ii) their performance depends on their parameterization and (iii) the best-performing parameterization found over the vegetated test area will yield misclassifications on non-vegetated rough terrain. In particular, if only small changes have occurred the choice of the filtering technique and its parameterization play an important role in estimating volume changes.

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Terrestrial laser scanning and exploratory spatial data analysis for the mapping of weathering forms on rock art panels

Geocarto International ◽

10.1080/10106040903524922 ◽

2010 ◽

Vol 25 (5) ◽

pp. 347-367 ◽

Cited By ~ 1

Author(s):

B. J. Vogt ◽

R. M. Edsall

Keyword(s):

Data Analysis ◽

Spatial Data ◽

Laser Scanning ◽

Rock Art ◽

Terrestrial Laser Scanning ◽

Spatial Data Analysis ◽

Exploratory Spatial Data Analysis

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Correcting for nondetection in estimating forest characteristics from single-scan terrestrial laser measurements

Canadian Journal of Forest Research ◽

10.1139/cjfr-2018-0072 ◽

2019 ◽

Vol 49 (1) ◽

pp. 96-103 ◽

Cited By ~ 6

Author(s):

Mikko Kuronen ◽

Helena M. Henttonen ◽

Mari Myllymäki

Keyword(s):

Simulation Study ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Basal Area ◽

Tree Density ◽

Laser Measurements ◽

Different Types ◽

Visible Area

A problem in the single-scan setup of terrestrial laser scanning is that some trees are shaded by others and therefore not detected in the scan. A basic estimator for forest characteristics such as tree density or basal area is based on the visible area of a scanner. However, simply compensating for nondetection by the visible area may result in considerable bias even in Poisson forests, especially if the detection of a tree depends on its size. We propose a new estimator that is a generalization of the visible area based estimator. Most importantly, the new estimator allows different detection rules; for example, full or partial visibility of a tree can be required for detection. By a simulation study, it is shown to work adequately in different types of simulated and empirical forests with different detection rules.

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3-D Modelling in Rock Art Research

The Oxford Handbook of the Archaeology and Anthropology of Rock Art ◽

10.1093/oxfordhb/9780190607357.013.45 ◽

2017 ◽

Cited By ~ 1

Author(s):

Stéphane Jaillet ◽

Jean-Jacques Delannoy ◽

Julien Monney ◽

Benjamin Sadier

Keyword(s):

Spatial Analysis ◽

High Resolution ◽

Laser Scanning ◽

Rock Art ◽

Terrestrial Laser Scanning ◽

Conservation Strategies ◽

The World ◽

Recent Developments ◽

Art Research

Recent developments in 3-D technology have resulted in considerable improvements in the recording and study of rock art sites in various parts of the world. These technologies make it possible to digitally document sites at nested scales, from detailed analyses of individual motifs on rock surfaces to entire sites in their broader landscape settings. Because of the increased precision that 3-D recordings bring, the results can be used to study the art and site settings, and to monitor and guide conservation strategies. This chapter outlines key principles underlying the production of 3-D imagery and how high-resolution 3-D models can benefit the spatial analysis of sites and landscapes and the interrelationship of features therein. The authors focus on terrestrial laser scanning (TLS) and photogrammetry, distinctive approaches that are often applied together for a richer outcome.

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COMPARISON OF SINGLE AND MULTI-SCALE METHOD FOR LEAF AND WOOD POINTS CLASSIFICATION FROM TERRESTRIAL LASER SCANNING DATA

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-3-217-2018 ◽

2018 ◽

Vol IV-3 ◽

pp. 217-223

Author(s):

Hongqiang Wei ◽

Guiyun Zhou ◽

Junjie Zhou

Keyword(s):

Classification Accuracy ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Multi Scale ◽

Scale Method ◽

Oak Trees ◽

Single Scale ◽

Speed Up ◽

Salient Features

The classification of leaf and wood points is an essential preprocessing step for extracting inventory measurements and canopy characterization of trees from the terrestrial laser scanning (TLS) data. The geometry-based approach is one of the widely used classification method. In the geometry-based method, it is common practice to extract salient features at one single scale before the features are used for classification. It remains unclear how different scale(s) used affect the classification accuracy and efficiency. To assess the scale effect on the classification accuracy and efficiency, we extracted the single-scale and multi-scale salient features from the point clouds of two oak trees of different sizes and conducted the classification on leaf and wood. Our experimental results show that the balanced accuracy of the multi-scale method is higher than the average balanced accuracy of the single-scale method by about 10&thinsp;% for both trees. The average speed-up ratio of single scale classifiers over multi-scale classifier for each tree is higher than 30.

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