Globally aligned photomosaic of the Lucky Strike hydrothermal vent field (Mid‐Atlantic Ridge, 37°18.5′N): Release of georeferenced data, mosaic construction, and viewing software

Abstract

[1] We present a georeferenced photomosaic of the Lucky Strike hydrothermal vent field (Mid-Atlantic Ridge, 37°18 0 N). The photomosaic was generated from digital photographs acquired using the ARGO II seafloor imaging system during the 1996 LUSTRE cruise, which surveyed a $1 km 2 zone and provided a coverage of $20% of the seafloor. The photomosaic has a pixel resolution of 15 mm and encloses the areas with known active hydrothermal venting. The final mosaic is generated after an optimization that includes the automatic detection of the same benthic features across different images (feature-matching), followed by a global alignment of images based on the vehicle navigation. We also provide software to construct mosaics from large sets of images for which georeferencing information exists (location, attitude, and altitude per image), to visualize them, and to extract data. Georeferencing information can be provided by the raw navigation data (collected during the survey) or result from the optimization obtained from image matching. Mosaics based solely on navigation can be readily generated by any user but the optimization and global alignment of the mosaic requires a case-by-case approach for which no universally software is available. The Lucky Strike photomosaics (optimized and navigated-only) are publicly available through the Marine Geoscience Data System (MGDS, http://www.marine-geo.org). The mosaic-generating and viewing software is available through the Computer Vision and Robotics Group Web page at the University of Girona

LAPMv2: An improved tool for underwater large-area photo-mosaicking

“…zones where the mosaic may be impacted by the largest errors. This way, in particular in flat areas or areas with low and gradual relief variations, 2D mosaicking techniques proved efficient at mapping large areas with an accuracy that permitted spatial analyses to be performed [10], [29], [26].…”

“…This behavior was likely due to the enormous amount of images causing instabilities in the GIS program, and the fix to that problem was not straightforward. In future versions, a workaround may involve using the mosaic viewing program developed by the Computer Vision and Robotics Group at the University of Girona and presented in [10].…”

“…The term fiducial points was introduced by [9] and [10], and refers to points on the seafloor with known absolute coordinates, such as landmarks or markers. Fiducial points can be used in the cost function as additional constraints to ensure that the given points will be registered correctly in the geo-referenced mosaic.…”

“…The global registration is done by minimizing expression (10) over the parameters of the transforms of all N images, i.e. over the parameters of .…”

Efficient Topology Estimation for Large Scale Optical Mapping

“…Therefore, mosaicing techniques are needed to create high-resolution maps of the surveyed area using a large number of acquired images and to get a global perspective of the underwater terrain [45,89,109,60,94,96]. Thus, robotic exploration with the aim of constructing photo-mosaics is becoming a common requirement in geological [112,33] and archaeological surveys [36], mapping [59], ecology studies [56,66,89], environmental damage assessment [41,65] and temporal change detection [29]. Owing to the rapid development in data acquisition platforms, there is an increasing need for large-scale image mosaicing methods.…”