Underwater Photogrammetry, Coded Target and Plenoptic Technology: A Set of Tools for Monitoring Red Coral In Mediterranean Sea in the Framework of the ”perfect” Project

Abstract

ABSTRACT:PErfECT 'Photogrammetry, gEnetic, Ecology for red coral ConservaTion' is a project leaded by the Laboratoire des Sciences de lInformation et des Systmes (LSIS -UMR 7296 CNRS) from the Aix-Marseille University (France) in collaboration with the Spanish National Agency for Scientific Research (CSIC, Spain). The main objective of the project is to develop innovative Tools for the conservation of the Mediterranean red coral, Corallium rubrum. PErfECT was funded by the Total Fundation. The adaptation of digital photogrammetric techniques for use in submarine is rapidly increasing in recent years. In fact, these techniques are particularly well suited for use in underwater environments. PErfECT developed different photogrammetry tools to enhance the red coral population surveys based in: (i) automatic orientation on coded quadrats, (ii) use of NPR (Non Photo realistic Rendering) techniques, (iii) the calculation of distances between colonies within local populations and finally (iv) the use of plenoptic approaches in underwater conditions.

Analysis of the population structure of a gorgonian forest (Placogorgia sp.) using a photogrammetric 3D modeling approach at Le Danois Bank, Cantabrian Sea

“…The possibility of studying and measuring this type of habitat in three dimensions, with an important vertical component, opens many possibilities for study. SfM techniques were used to study a Mediterranean red coral population (Drap et al, 2017), but the colonies were sampled by divers in a small area due to the complexity entailed in the field work. The morphometric complexity of the habitat in a coral reef was also studied (Ferrari et al, 2016;Anelli et al, 2017), focused on the determination of habitat complexity measurements such as roughness and curvature using Digital Surface Models and Digital Terrain Models and their derivatives.…”

Fundamentals of 3D imaging and displays: a tutorial on integral imaging, light-field, and plenoptic systems

“…For the evaluation of the resolution limit and the DoF provided by the IMic, we must adapt Eqs. (44) and (45) to the microscopy regime, and therefore we obtain…”

“…InIm technology has been proposed also for wavefront sensing [35], 3D imaging using long-wave infrared light [36,37], head-mounted display technology [38], or large 3D screens [39,40]. The utility of the plenoptic concept is spreading very fast and reaching even some exotic applications, such as giga pixel photography [41], 3D polariscopy [42], the inspection of road surfaces [43], or the monitoring of the red coral [44]. An application of integral photography that deserves special attention is 3D microscopy.…”

Quasi-Orthorectified Projection for the Measurement of Red Gorgonian Colonies

“…Shortis (Shortis et al, 2009) provided a detailed overview of how non-rigid bodies can be easily measured by the use of stereo cameras. In (Drap et al, 2017) authors developed some effective photogrammetric tools for the monitoring of Mediterranean red corals using a specific designed hardware/software. A 3D printed frame equipped by coded targets provides a local reference system for a series of observation; camera poses were computed using targets and a dedicated interface was developed to take measurements directly from calibrated images.…”