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ACCESSIBILITY TO UNDERWATER CULTURAL HERITAGE: INTERACTIVE WEB NAVIGATION OF THE ROMAN SUBMERSED VESSEL OF CALA MINNOLA

The possibilities offered by photogrammetric reconstruction based on computer vision algorithms allowed in recent years to develop new interesting solutions for the use and dissemination of knowledge on Cultural Heritage (CH). In the same way, the recent technological development in the field of Virtual Reality (VR) has offered new possibilities for the creation of interactive virtual environments which can be freely accessed via the browser using any type of device. These technologies acquire an additional relevance if applied to archaeological sites or monuments that are difficult to access, or even totally inaccessible, except by specialized personnel. In this case the virtual fruition on web becomes strategic for the valorization of CH, as in the case of submerged archaeological sites, where the virtual tour represents in fact the only opportunity of diffuse accessibility. The present case shows the virtual reconstruction of the wreck area of the Roman ship found on the seabed of Cala Minnola on the island of Levanzo (TP, Italy). The model, obtained from a Structure from Motion (SfM) processing of a chunk of photos originally intended for a traditional photogrammetric survey, was edited and inserted into a specific template based on HTML5 and linked to Javascript libraries (Three.js) which allowed browsing on web. Subsequently, the navigation model was appropriately adapted to the purpose, so as to make the use of the network more intuitive possible, considering any type of device and using the most common browsers (Chrome, Safari, Firefox). This experimentation is a viable procedure for spreading the knowledge of a submerged archaeological site in a simple way, by web-browsing. This type of navigation models with the future development of 5G networks will find greater diffusion and application, with the possibility of including increasingly complex environments in the navigation.