Massive stereo-based DTM production for Mars on cloud computers

Digital Terrain Model (DTM) creation is essential to improving our understanding of the formation processes of the Martian surface. Although there have been previous demonstrations of open-source or commercial planetary 3D reconstruction software, planetary scientists are still struggling with creating good quality DTMs that meet their science needs, especially when there is a requirement to produce a large number of high quality DTMs using "free" software. In this paper, we describe a new open source system to overcome many of these obstacles by demonstrating results in the context of issues found from experience with several planetary DTM pipelines. We introduce a new fully automated multi-resolution DTM processing chain for NASA Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE) stereo processing, called the Co-registration Ames Stereo Pipeline (ASP) Gotcha Optimised (CASP-GO), based on the open source NASA ASP. CASP-GO employs tie-point based multi-resolution image co-registration, and Gotcha sub-pixel refinement and densification. CASP-GO pipeline is used to produce planet-wide CTX and HiRISE DTMs that guarantee global geo-referencing compliance with respect to High Resolution Stereo Colour imaging (HRSC), and thence to the Mars Orbiter Laser Altimeter (MOLA); providing refined stereo matching completeness and accuracy. All software and good quality products introduced in this paper are being made open-source to the planetary science community through collaboration with NASA Ames, United States Geological Survey (USGS) and the Jet Propulsion Laboratory (JPL), Advanced Multi-Mission Operations System (AMMOS) Planetary Data System (PDS) Pipeline Service (APPS-PDS4), as well as browseable and visualisable through the iMars web based Geographic Information System (webGIS) system

Determination of the Interior Orientation Parameters of a Non-metric Digital Camera for Terrestrial Photogrammetric Applications

AbstractHigh cost of metric photogrammetric cameras has given rise to the utilisation of non-metric digital cameras to generate photogrammetric products in traditional close range or terrestrial photogrammetric applications. For precision photogrammetric applications, the internal metric characteristics of the camera, customarily known as the Interior Orientation Parameters, need to be determined and analysed. The derivation of these parameters is usually achieved by implementing a bundle adjustment with self-calibration procedure. The stability of the Interior Orientation Parameters is an issue in terms of accuracy in digital cameras since they are not built with photogrammetric applications in mind. This study utilised two photogrammetric software (i.e. Photo Modeler and Australis) to calibrate a non-metric digital camera to determine its Interior Orientation Parameters. The camera parameters were obtained using the two software and the Root Mean Square Errors (RMSE) calculated. It was observed that Australis gave a RMSE of 0.2435 and Photo Modeler gave 0.2335, implying that, the calibrated non-metric digital camera is suitable for high precision terrestrial photogrammetric projects. Keywords: Camera Calibration, Interior Orientation Parameters, Non-Metric Digital Camer

Optimization of survey procedures and application of integrated digital tools for seismic risk mitigation of cultural heritage: The Emilia-Romagna damaged theatres.

Starting from current procedures, standards and tools for seismic damage survey, the research presents an integrated workflow for seismic damage documentation and survey applied to historic theatres in the Emilia-Romagna region damaged by the 2012 earthquake. The 2012 earthquake highlighted the fragility of the cultural heritage and underscored the lack of proactive conservation and management of historic assets. The research starts by analysing Agenzia Regionale per la Ricostruzione della Regione Emilia-Romagna- ARRER’s requests, which had found criticalities in applying the current Mic (Ministero della Cultura) procedures for the damage survey of complex types: the A-DC form for churches and the B-DP form for buildings. Using the two types of forms highlighted the lack of ad hoc tools for complex architectural styles such as castles, cemeteries and theatres, resulting in the loss of quantitative and qualitative information necessary for knowledge, conservation and thus management of the reconstruction process. As a result of these considerations, national and international standards of integrated documentation, existing digital databases for cataloguing and classification of cultural property, and seismic risk management were studied to develop a workflow of integrated procedures for seismic damage survey on the specific assigned case study: Regional Historic Theaters affected by the 2012 earthquake. The research used the holistic and interdisciplinary approach of integrated documentation to develop the integrated procedural workflow to enhance and optimise seismic damage detection operations in the case study. In providing a workflow of integrated procedures for the prevention and mitigation of hazards related to potential states of emergency, both natural and anthropic, the research follows an “extensive” methodological approach to test the survey outside the Emilia crater. The methodological framework led to the critical-comparative analysis, divided into two levels: the first involved studying critical issues in the B-DP form, mainly used in the 2012 theatre survey. The second level covered the techniques - laser scanning, digital photogrammetry - and integrated survey methodologies applied during the in-depth investigations for repair and restoration work. The critical-comparative analysis and morpho-typological study led to the development of an integrated procedural flow to survey damage in historic theatres. It is aimed at systematising and optimising the stages of damage documentation. The workflow consists of three information levels: L1. Screening level for the visual survey; L2 survey level defines the 3D acquisition steps for the geometric-dimensional study by theatres. The BIM L3 Plus level guides implementing the level of knowledge of parametric HBIM models for documentation, management and monitoring of historic theatres