Amine Mahiddine

Underwater image preprocessing for automated photogrammetry in high turbidity water: An application on the Arles-Rhone XIII roman wreck in the Rhodano river, France

ROV 3D project aims at developing innovative tools which link underwater photogrammetry and acoustic measurements from an active underwater sensor. The results will be 3D high resolution surveys of underwater sites. The new means and methods developed aim at reducing the investigation time in situ, and proposing comprehensive and non-intrusive measurement tools for the studied environment. In this paper, we apply a pre-processing pipe line to increase the SIFT and SURF descriptors extraction quality in order to solve the problem of surveying an underwater archaeological wreck in a very high condition of turbidity. We work in the Rhodano river, in south of France on a roman wreck with 20 centimeters visibility. Under these conditions a standard process is not efficient and water turbidity is a real obstacle to feature extraction. Nevertheless the mission was not dedicated to an exhaustive survey of the wreck, but only a test to show and evaluate the feasibility. The results are positive even if the main problem seems now to be the time processing, indeed the poor visibility increase drastically the number of photographs.

Underwater Photogrammetry for Archaeology. What Will Be the Next Step

Since 1973 archaeology and computer science have developed close ties in Marseille. Two departments (computer science and archaeology) from the French National Centre for Scientific Research (CNRS) in Marseille started working together and laid the cornerstone of the Computer Applications and Quantitative Methods in Archaeology (CAA) community. Marseille also has the advantage of being located in a very interesting place on the Mediterranean Sea and being the home to several famous laboratories, such as the French Cultural Heritage Department (DRASSM) or private companies like COMEX. In 1980 they performed a series of explorations of a deep-sea wreck with the help of COMEX and DRASSM. In this paper we present new advances in underwater photogrammetry for archaeology based on forty years of experience. The survey described in this article does not only discuss the acquisition of 3D points in difficult conditions but also linking archaeological knowledge to the surveyed geometry. This approach needed to com...

ROV-3D: 3d underwater survey combining optical and acoustic sensor

ROV 3D project aims at developing innovative tools which link underwater photogrammetry and acoustic measurements from an active underwater sensor. The results will be 3D high resolution surveys of underwater sites. The new means and methods developed aim at reducing the investigation time in situ, and proposing comprehensive and non-intrusive measurement tools for the studied environment. In this paper, we are presenting a new method of 3D surveys which are dedicated to high resolution modeling of underwater sites. The main met constraints in situ are taken into account and this method leads to a precise 3D reconstruction. Some examples will present both the main obtained results and their limitations. We will end with the perspectives and the necessary improvements to the method, so as to automate the multimodal registration step.

Partial 3d-object retrieval using level curves

3D object recognition from 3D scenes, is one of the challenges of several researchers in the field of computer vision, engineering and Robotics. The occlusion is one of the problems that we can found. One of the possible solutions in this situation is to find a part of an object in the scene that can be identified. For this reason, we are mainly interested to partial shape retrieval methods. In this paper, we present a new approach for 3D partial object retrieval based on level curves matching. Our approach can be used as an alternative solution for classification-based methods. We generate in the off-line step a dataset by using a viewing sphere to extract levels curves at different points of view. The level curves are a set of 2D planar contours that are the projection of points on several perpendicular planes. The level curves of each query partial object is compared with a set of level curves that define one 3D object from the dataset. The number of matched curves between a partial object and complete object represent the weight of that class. The class with the heavy weight is identify as the class of the query object.

Underwater Multimodal Survey: Merging Optical and Acoustic Data

ROV 3D project aims at developing innovative tools which link underwater photogrammetry and acoustic measurements from an active underwater sensor. The results will be 3D high resolution surveys of underwater sites and landscapes useful to keep in memory cultural and natural heritage. The new means and methods developed aim at reducing the investigation time in situ, and proposing comprehensive and non-intrusive measurement tools for the studied environment.

Recalage hétérogène de nuages de points 3D : Application à l'imagerie sous-marine

Le recalage de deux nuages de points 3D est une etape essentielle dans de nombreuses applications. L’objectif de notre travail est d’estimer une transformation isometrique permettant de fusionner au mieux deux ensembles heterogenes de points issus de deux capteurs differents. Dans cet article, nous presenterons une methode de recalage 3D - 3D originale qui se distingue par la nature de la signature extraite en chaque point et par le critere de similarite utilise pour mesurer le degre de ressemblance. Le descripteur que nous pr oposons est invariant a la rotation et a la translation et permet egalement de s’affranchir du probleme de la multi - resolution relatif aux donnees heterogenes. Dans le but de valider notre approche, nous l’avons teste sur des donnees synthetiques et nous l’avons applique sur des donnees reelles heterogenes.