HIDDEN GRAFFITI IDENTIFICATION ON MARBLE SURFACES THROUGH PHOTOGRAMMETRY AND REMOTE SENSING TECHNIQUES

Abstract. Nowadays, considering the various methodological approaches used by the scientific community to study graffiti, there is a need for the improvement of the documentation and analysis workflow that must be addressed. Historic graffiti are recognized by scholars of different disciplines as a relevant and genuine written source, able to provide an insight into the everyday life of the past. Many studies have indeed flourished during the last decades stating the relevance of graffiti as a multidisciplinary source of information and showing, at the same time, the fragmented research scenario due to the lack of reliable and standardized methodologies. Currently, the scientific community involved in the study of graffiti has largely benefited from the use of digital technologies. However, most of the efforts and research projects were focused on the analysis of graffiti immediately visible on the surface or graffiti the position of which was easily identifiable due to the depth and width of the engraving. The proposed study is intended to tackle the documentation pipeline a step earlier than the documentation itself when the graffiti are yet to be identified. The San Marco Basilica in Venice is used as a unique case study for the analysis of non-directly visible-to-human-eye graffiti in a rather challenging environment.