Ancient Landscape Reconstruction

Transcription

1 1 Ancient Landscape Reconstruction Sofia Pescarin CNR ITABC VHlab - Rome, Italy sofia.pescarin@itabc.cnr.it

2 2 Summary 1) Virtual Archaeology 2) Landscape (archaeological, ancient, potential) 3) Method > explicit approach (scientific method, london charter principles, vision/visualisation) 4) Workflow 5) Examples

3 3 Virtual Archaeology basics The term virtual archaeology was proposed for the first time in 1990 by Paul Reilly as referred to the use of 3d models of monuments and objects. Virtual is commonly used as a generic term and as referred to a wide variety of interactive visualisation (Gillings 1999). It is also one of the term mostly used inappropriately. Several 3d representations should not be properly called virtual, lacking completely of interaction.

4 4 Virtual Archaeology simulation process Virtual Archaeology is aimed at studying, interpreting, understanding, communicating the archaeological heritage and its context, through a process of acquisition, reconstruction and continuous verifying. Virtual Archaeology is not a simple digital reproduction of an archaeological artefact, monument, site. It is most of all a simulation process where various elements can be combined: behaviours, objects, ecosystems... and through which identify different potential realities of the information. Thus obtaining a cognitive increment. Virtual Archaeology makes use of a multi-disciplinary approach, open and transparent, of interactive 3d spatial environments obtained through different kind of interaction techniques (DGPS, Laser Scanner, Photogrammetry), 3d post-processing, etc. Different can be tools and styles of communication: from movie to multimedia, from immersive VR, to virtual story telling, from complex simulations to artificial life

5 5 Virtual Museums Rome Total War Foundation of the Hellenic World: Thermopyle Battle Assassin's Creed Rome 3D, Altair4

6 6 Virtual Museums It is not on line versions of real museum (at least not necessarily). Virtual museums are a new model of communication for the museum sector that aims at creating a personalised, immersive and interactive way to enhance our understanding of the past. The term virtual museum covers a wide variety of digital systems and applications data information knowledge Engagement, experience CH ICT Cognitive sciences Design Art USERS society

7 7 Virtual Archaeology One of the goal of virtual archaeology is landscape reconstruction But what can we reconstruct? And How? We should distinguish between Archaeological Landscape and Ancient Landscape

8 8 Landscape: archaeological Contemporary landscape in its diacronic dimension We are in the landscape It is an ecosystem which includes archaeological structures but not only But archaeology does not only deal with the study of sites and artefacts. It also deals with dynamics...

9 9 Landscape: Ancient How did the man in past used to leave, to see, to use the space, his territory? Which are elements that helped him to classify and what was there value? Within the same settlement, the inhabitants were seeing and living the territory differently in accordance to their role and hierarchy? How could we answer to those questions? > it is useful to have a system able to build and test models and simulations, even complex. An interactive real time system could be useful

10 10 Landscape: potential landscape reconstruction Reconstruction of ancient potential landscape, through: Geomorphology Water system Potential soil use > vegetation Reconstruction of the anthropic aspect of the landscape (sites, monuments): Road system Settlements Relation (man/man, man/environment)

11 11 Landscape How could have potentially being a territory in certain historical period, at a certain latitude and elevation? Based on: Studies related to ecological attitude of a territory* Studies related to land unit and potential use of the soil*. Palaeo-environmental and paleo-climatic studies.. Nevertheless it is necessary to manage a high level of uncertainty It requires a scientific approach, based on a theoretical explicit approach* (see New Archaeology) Di Fidio 1993; FAO 1976; Renfrew Bahn 1995

12 12 Landscape: potential landscape reconstruction ecological attitude It is possible to start defining the ecological attitude of a terrain [DI FIDIO], obtained when it follows its natural characteristics, compared to its shape:.i.e. Forest terrains and Agricultural terrains

13 13 Land evaluation : A framework for land evaluation, FAO Soils bulletin 32 Land evaluation derives from the interpenetration of the pedological map as the basic information. It shows how soils are distributed and their characteristics.

14 14 Landscape: Issues - How can we build a virtual archaeology model (reality-based) - How the reconstruction process can be a gateway to an explanation and description of the past? - How could you manage the reconstruction where there are fragmentary data? - How the acquisition work can be planned and carried out as to obtain the highest reliability and accuracy? - realismo vs. reality?

15 15 Methodology: visualisation, selection, ambiguity Reconstruction > interpretation based on complex analysis of sources of various kind. In interpretation, vision has a central role. Even result is visual Mechanisms of visualisations > neuro biological approach How do we get to know the world around? We observe in order to acquire information and finally knowledge. This is done in 3 steps: classification, selection and identification of essential elements (constants) From different variable information we are able to select constant proprierties, than we do not consider what is not relevant and finally we compare this with what it is already in our brain Although information continuously changes, we are built to understand and get to know the world

16 16 Interpretation Reconstructing and not replicating the elements that characterised them = identification of invariants and representative aspects Ambiguity = positive element, it represent the various possibilities Reconstruction through the interpretation process > increase of knowledge through the combination of information [Bateson, Mind and Nature] Interpretation starts with an analytic process: a) de-composition (identification of single elements, phenomenon, land units etc.) b) ri-composition

17 17 Realism and reliability > Scientific Method > Reconstruction has to face high level of uncertainty > Realism is instinctively read as reliability > Some passive media do not allow to get what is behind reconstructions. It should therefore be based on the scientific method. It should be: Repeatable; Verifiable; Transparent; Documentable Steps*: initial definition of the issues to be studied; information and sources; hypothesis development; experiments, data collection and analysis; interpretation; conclusion; new hypothesis; results publication S. Turkle,Life on the Screen, 1996; D. Schafersman, An Introduction to Science Scientific Thinking and the Scientific

18 18 Method: London Charter Principle 1- Implementation The principles of the London Charter are valid wherever computerbased visualisation is applied to the research or dissemination of cultural heritage. Principle 2- Aims and Methods A computer-based visualisation method should normally be used onlywhen it is the most appropriate available method for that purpose. Principle 3: Research Sources In order to ensure the intellectual integrity of computer-based visualisation methods and outcomes, relevant research sources should be identified and evaluated in a structured and documented way.

19 19 Principle 4: Documentation Sufficient information should be documented and disseminated to allow computer-based visualisation methods and outcomes to be understood and evaluated in relation to the contexts and purposes for which they are deployed.

20 20 Method Transparent models Level of reliability *** very reliable ** probable * evocative

21 21 Method Principle 5: Sustainability Strategies should be planned and implemented to ensure the longterm sustainability of cultural heritage-related computer-based visualisation outcomes and documentation, in order to avoid loss of this growing part of human intellectual, social, economic and cultural heritage. Principle 6: Access The creation and dissemination of computer-based visualisation should be planned in such a way as to ensure that maximum possible benefits are achieved for the study, understanding, interpretation, preservation and management of cultural heritage.

22 22 Workflow

23 23 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 What do I need Basic requirements 1) Digital Elevation Models 2) GeoImage 3) Thematic Layer (vett) i.e. vegetation 4) Thematic Layer (3d) Tools: 1) GIS 2) image processing 3) Terrain Generator 4) 3d modelling 5) authoring VR

24 24 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 sources Basic cartography (CTR/IGM) Historical maps Soil maps, vegetation maps (vector/raster) Archaeological maps and excavation maps Satellite imagery Aerial photographs (historical, vertical, oblique) Contour lines and elevation points > DEM Historical, literary sources (Paleo) environmental data (pollen, geomorphology, lithography)

25 25 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Sources: satellite repositories on line Satellite imagery (i.e. landsat) is relatively high resolution earth observation data that is acquired through sensors on satellites. The satellite sensors acquire high integrity images of the planet surface. Users can take this imagery and use it to determine health and type of vegetation, amount of built surfaces, agriculture, or apply it for other uses. Global Land Cover Facility (GLCF) provides earth science data and products to help everyone to better understand global environmental systems Landsat satellite images: 30 mt Satellites Ikonos: < 1mt Quickbird: 80 cm Aerial photos: > 20 cm

26 26 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Sources: DEM Aster program ASTER Global Digital Elevation Model (ASTER GDEM) The Ministry of Economy, Trade and Industry of Japan (METI) and the National Aeronautics and Space Administration (NASA) are collaborating on a project to develop ASTER Global Digital Elevation Model (ASTER GDEM), a DEM data which is acquired by a satellite-borne sensor "ASTER" to cover all the land on earth. What is ASTER?: an earth observing sensor developed in Japan What ASTER tells us: 1) Surface condition; 2) Surface temperature; 3) DEM DEM is generated from a stereo-pair of images

27 27 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Soil maps It represents the characteristics of the soils (upper layer of the soil) in relation with its geomorphology, lithology, etc. What is represented in the map: substratum, deepness, type of texture, drainage, slope, agro-environmental characteristics

28 28 VU6: Volcanic soils, deep, plain or low slope. Dominant soil use: vineyard, fruit, crops, pasture VS2: Volcanic soils, limited deepness, mainly stony, limited slope or plain. Dominant soil-use: vineyard, crops or pasture VD: Volcanic soils, deep, with little depressions in the upper planes, low slope or plains. Dominant soil-use: crops SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011

29 29 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Land Units Land Unit: area of a terrain drawn on a map that has specific characteristics/quality of terrain (FAO 1976). Developed originally for land evaluation For every unit is given: geological and morphological aspects, climate, hydrological, vegetation aspects, anthropic activities

30 30 Unit 4: Volcanic relieves drained by small rivers Subunits: 4a) volcanic tops, undulated, dominant pumice 4b) steep and deep valleys 4c) isolated volcanic relief, with slag and lava 4d) volcanic hills with dominant pumice Lithology: pumice, lithoid tuff Morphology: wavy landscape or hills with not deep valleys Hydrography: radial network Soils: not deep, locally stony, medium texture. Dominant soil use: mix agriculture, crops, locally woods SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011

31 31 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 On the field Passive sensors: digital cameras - they store the (electromagnetic) information visible in the scene and deliver e.g. images Active sensors: laser scanners - the emit a signal and observe its deformation or wait for a response Photogrammetry: derives metric information from images - measurements in images (also manually) with precision and reliability in mind widely separated views Remote Sensing: image (satellite) interpretation and classification no geometric processing Computer vision: image processing and 3D in a fully automated way with no interest to accuracy - closely separated images Computer graphic: image and model representation, rendering for impressive and nice looking results

32 32 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 (4) Tools GPS Remote Sensing Scanner Laser Photogrammetry Computer Vision GIS (GRASS, QGis) Remote-Sensing/GIS (GRASS, Erdas) Software ponts/mesh ( Riscan, Cyclone, Meshlab) Software Photgrammetry (I.e. photomodeler) DEM Geoimages (sat./aerial) Pointclouds/meshes DEM, 3d model (mesh textured)

33 33 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 GIS Geographical Information System is the technology made of hardware/software/data, that enable to position, analyse, simulate objects and events that happened on the earth It is used in any situation where the spatial component is important GIS enables to: Archive Overlay Visualise Manage. Spatial Analysis

34 34 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Spatial Analysis DTM (data interpolation) Analysis of slopes (Slope) Analysis of the exposition of the sides of hills/mountains (Aspect) Definition of areas around vector objects (Buffer) Visibility analysis (Viewshed) Identification of areas influence around points (Thiessen Polygons) Cost Analysis Resources accessibility analysis (time/distance and other factors) Site Catchment; Site Exploitation Territory analysis (identification of terrains potentially good for agriculture > identification of max extension of a site based on the distance a farmer can reach for his work). It is obtained combining different analysis

35 35 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Ecosystem generation

36 36 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Terrain generation

37 37 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Open source solutions OpenSceneGraph > OSGdem L3 Virtual Terrain Project > VTP, ENVIRO L0 L1 L2

38 38 SCUOLA NAZIONALE DI ARCHEOLOGIA VIRTUALE 2011 Commercial solutions Blueberry3d Terravista > Terrex now Presagis (15000 $) Visual Nature Studio VNS by 3dnature (1000 Euro) Terragen Vue by E-on software, from $100 to $600 depending on product: Attractive nonrealtime landscape renderer CityEngine > ESRI/Vue

39 39 Examples: Integrated Technologies of robotics and virtual environment in archaeology Robotics and Virtual Environments: "Integrated Technologies of robotics and virtual environment in archaeology" VR multiuser domain in the web, for scientific communities. Funded by FIRB projects Tools > Virtools Dev, 3d studio max

40 40 Examples: Matera pliocene neolithic Norman nowadays

41 41 Examples: Virtual Rome Virtual Museum of Ancient Via Flaminia Tools > OpenSceneGraph: OSGdem, OSG4WEB Tools > Virtools Dev, 3d studio max

42 42 Examples: Ca' Tron Tools > VTP, GRASS Ca' Tron

43 43 Examples: Medieval Dublin Tools > Flash. 3D Studio Max

44 44 Examples: Apa Tools > Blender

45 45 Examples: Aquae Patavinae Tools > OpenSceneGraph, OSG4web