Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz Methodological contest between high-end hardware and low- cost equipment for archaeological documentation keywords structure from motion, image-based modeling approach, 3D geo-spatial field technology, archaeological data acquisition, 3D laser scan, FOSS, GRASS GIS, high resolution digital documentation technique Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Transcript
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Methodological contest between high-end hardware and low-cost
equipment for archaeological documentation
keywordsstructure from motion, image-based modeling approach, 3D geo-spatial field technology, archaeological data acquisition, 3D laser scan, FOSS, GRASS GIS, high resolution digital documentation technique
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction -> Research question, State-of-the-art of digital documentation methods
Aim -> Comparison of two methods
Case study -> Ostia Antica
Results -> And the winner is …!
Outlook -> Future perspectives
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
Research question
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
State-of-the-art of digital documentation methods in Prehistoric Archaeology
First application of terrestrial laserscanners in Prehistoric Archaeology by VIAS Wien
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
Advantages & Disadvantages
- High quality and precise documentation- immediate control- Hardware: quick and easy to use- Software: can be operated intuitively
after an introduction- Fast and easy referencing and geo-
referencing possible- Fast data processing = data preparation
- Time consuming because of mostly more than one scanworld is needed
- Every scanworld needs a new registration by scanning all targets = time consuming
- Hardware: havy equipment- Difficult custum regulations in
certain countries- Very expensive equipment- Software: Very expensive
proprietary for documentation and first data preparation
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
State-of-the-art of digital documentation methods in archaeology
Computer Vision / Structure-from-motion
- originally developed for Tourism / Social networking purposes
- Online-Services like Photosynth or Photofly for all all kinds of use:
private, construction, forensics, design…
-> ca. 150 industries using it (NY Times)
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Computer Vision / Structure-from-motion
- Adaption for archaeology as a low-cost alternative to laser scanning
- different packages available:
- Proprietrary: Photoplan, Arctron aspect3D
- Open source: ArchOS, BundlerTools, VisualSFM
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
Advantages & Disadvantages
Advantages:
- little gear
- low-cost
- time-saving (on-field)
- more weather resistent
- flexible
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Disadvantages
- spatial cover
- post-processing (Workflow)
- no immediate control
- required compute power (but no cloud-computing necessary)!
- georeferencing
Advantages & Disadvantages
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
Comparison of two methods
Laserscanning Structure-from-MotionHardwarePrice High LowTransport Heavy and difficult Just one photo camera ist neededAdditional Equipment + Tripod, + Notebook, + certain
targetsNo
Power supply Needed NeededAcquisition time 6x as long as SfMWorkflow stepsdistance, spatial cover The longer the distance, the
lower the resolution .
field of application Architectur, Prehistoric Excavation.
Weather sensibility Not applicable by rain and temperature higher 40°C and
lower – 40°C.
Handling management Difficult to handle
SoftwarePrice highUsability can be operated
intuitively after an introduction
MaintenanceProcessing timePost-processing
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
OfficeFreyensteinOstia Antica
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
Ostia Antica
1. 489.381, 702.880, 2.747
2. 490.217, 701.778, 2.813
3. 488.992, 702.380, 2.844
4. 490.498, 702.327, 2.781
1. 489.376, 702.918, 2.725
2. 490.206, 701.811, 2.813
3. 488.969, 702.372, 2.857
4. 490.475, 702.319, 2.767
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
164 743 vertices
Laserscan (resolution 1 mm, 1 Scanworld)
Structure-from-motion
238 247 vertices
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
Introduction
Aim
Case study
Results
Outlook
Ostia Antica
• Taking pictures: easy
• Taking usable pictures, some things to think of:
• Good camera objective helps
• large memory cards necessary
• Don´t forget targets for measurements and
color balance
• more cameras would even speed up
• assure the overlap!
• Laptop on site for instant check of photos and
running of small models
Data acquisition of structure from motion
Undine Lieberwirth, Bernhard Fritsch, Markus Neteler, Markus Metz
