Le site d&8217;Azrou Iklane : un exemple d&8217;usage de l&8217;imagerie numérique pour l&8217;étude et la préservation de l&8217;art rupestre saharien = The Azrou Iklane site in Morocco, an example of digital imaging for the study and preservation of rock painting in the Sahara

From 2013 to 2017 an archaeological study was carried out at the Azrou Iklane site of rock art in Morocco. The French-Moroccan team was led by G. Graff with the collaboration of several academic researchers (IRD, University of Aix-Marseille, CNRS, CNPR) and a professional historic monuments photographer. The site comprises a slab of sandstone measuring 120m by 20m, covered in thousands of engravings, protohistoric, Bovidien style ones, medieval ones (Libyco-Berbere) and recent and modern ones. The aims of the study were to establish original methodologies for the complete recording of the engravings and the development of a digital tool for their virtual preservation and to make them accessible to the general public, in spite of the site's isolated location. From a scientific point of view, the digital tool would also have to be able to take into account an understanding of the graphical overlapping of the engravings through time. In agreement with the country's heritage authorities, the project comprised a mapping of the area using a differential global positioning system, employed to elaborate a digital elevation model. This model was then enriched with the survey of the engravings carried out in a vector format drawing (done with machine intelligence), a photographic coverage using Gigapixel, the virtual visits and 360 degrees images in the manner of Google Street View. Using the data acquired, a geographical information system is now being elaborated, The Moroccan heritage services were keen supporters of this project which was an original one for the country and one that satisfied local demands for a better preservation and interpretation of the fragile engravings. The different methodologies used, allowing for a fuller appreciation of the environmental and anthropological contexts and the precise record of each engraving, will facilitate the semiological analysis of the site, phase by phase or diachronically. They will also contribute to the interpretation and preservation of this site, of major significance in the realm of Moroccan rock art