Example for Archaeology a User Perspective
Dorel Micle,
Department of History, UVT
Daniela Zaharie,
Department Computer Science, UVT
A historian perspective
„
What is the current approach in training students in
archaeology?
‰
‰
„
Mainly based on field surveys
Visual inspection and interpretation of aerial images
What do we need ?
‰
‰
Access to (high resolution) satellite images (e.g. IKONOS,
QuickBird) of regions in Romania
Tools for assisting the process of analyzing satellite images in
order to identify traces of ancient human activity
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A historian perspective
First requirements
Motivation
„
„
Assist the students in history to
identify archaeological sites
„
Image enhancement
„
Help in identifying
morphographical elements
Detailed analysis of known
archaeological sites in order to
identify new anthropological
characteristics
‰
‰
„
„
Identify new archaeological sites
Help in identifying
morphometrical characteristics:
‰
‰
GridTDT3
Circular shapes
Linear shapes
Size of pits houses
Distribution and distances
between pits houses
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Examples
„
Sites of ancient settlements
[Seceani, Timis, Romania]
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Examples
„
Sites of ancient settlements
(Shape: ring)
[Seceani, Timis, Romania]
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Examples
„
Sites of ancient settlements
[Darsele, Timis, Romania]
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Examples
„
Sites of ancient settlements
(Shape: disk)
[Darsele, Timis, Romania]
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Training scenario
„
Given: image containing elements of
interest (human settlements, ancient
roads, fortifications)
„
Required: identify the placement of
the element and its characteristics
„
Steps:
‰ Enhancement of the details in the
image
‰ Isolation of the region of interest
‰ Localization of the elements
‰ Interpretation
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[Seceani, Timis, Romania]
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Searching for circular shapes
Enhancing the details in the image:
‰ Gray level conversion
‰ Histogram equalization
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Searching for circular shapes
Locating the elements of interest:
Layer 1: original image
Layer 2: transformed image
‰ gray level, histogram equalization,
quantization, thresholding
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Searching for circular shapes
Locating the elements of interest:
Original image
Composed layers
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Searching for circular shapes
Interpretation:
Summary of image transformations:
‰
‰
‰
‰
Gray level conversion
Histogram equalization
Quantization (5 gray levels)
Thresholding (T=127)
Remark: simple image
transformations allows to enhance
details and identify elements
otherwise difficult to be identified:
‰ extension of areas corresponding
to human activities (house yard)
‰ areas with different kinds of human
activities (roads, squares etc)
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Searching for circular shapes
Interpretation:
Summary of image transformations:
‰
‰
‰
‰
Gray level conversion
Histogram equalization
Quantization (5 gray levels)
Thresholding (T=127)
Remark: simple image
transformations allows to enhance
details and identify elements
otherwise difficult to be identified:
‰ extension of areas corresponding
to human activities (house yard)
‰ areas with different kinds of human
activities (roads, squares etc)
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Searching for circular shapes
Interpretation:
Summary of image transformations:
‰
‰
‰
‰
Gray level conversion
Histogram equalization
Quantization (5 gray levels)
Thresholding (T=127)
Remark: simple image
transformations allows to enhance
details and identify elements
otherwise difficult to be identified:
‰ extension of areas corresponding
to human activities (house yard)
‰ areas with different kinds of human
activities (roads, squares etc)
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Searching for circular shapes
Another example – same sequence of image processing
operations
[Rural settlement: Murani Darsele, Timis, Romania]
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Searching for circular shapes
Another example – same sequence of image processing
operations
[Rural settlement: Murani Darsele, Timis, Romania]
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Searching for circular shapes
Another example – same sequence of image processing
operations
[Rural settlement: Remetea Mica, Timis, Romania]
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Searching for circular shapes
Another example – same sequence of image processing
operations
[Burial mounds: Nerau, Timis, Romania]
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Searching for linear shapes
Example: linear fortifications
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Searching for linear shapes
Operations:
‰ gray level conversion, emboss, histogram equalization
Layer 1: original image
Layer 2: equalized embossed image
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Searching for linear shapes
Operations:
‰ gray level conversion, emboss, equalization, layers subtraction
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Summary of elements of interest
‰ Human settlements without fortifications
‰ Circular shapes (rings, disks)
‰ Closed fortifications
‰ Closed curves
‰ Linear fortifications (waves like structures)
‰ Parallel lines
‰ Ancient roads
‰ Linear shapes
‰ Burial mounds
‰ Circular shapes
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Flows of basic operations
Enhancement of shapes
corresponding to ancient
settlements
Enhancement of linear shapes
corresponding to wave-like
fortifications
‰ Gray level converting
‰ Gray level converting
‰ Histogram equalization
‰ Emboss (convolution operation)
‰ Quantization and/or binarization
‰ Histogram equalization
‰ Layers combination
‰ Layers combination
Tool used in tests: GIMP (GNU Image Manipulation Program)
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Identified challenges
‰ The buried archaeological remains are expressed by
weak signals which are obscured by stronger signals
emitted by actual structures (roads, buildings)
‰ Data fusion (panchromatic and multispectral images)
‰ It is difficult to discriminate between ancient and actual
structures
‰ use of GIS information (current road networks)
‰ use of expert knowledge (e.g. ancient settlements were usually on
northern part of hills, near river etc.)
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Conclusions
‰ Even flows of basic operations on images allow to enhance the
image in order to identify easier by visual inspection the elements of
interest
‰ Useful in training of students in landscape archaeology
‰ More sophisticated operations are needed to develop a semiautomated tool able to identify the location of elements of interest and
to assist the user in obtaining morphometrical information
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