Documenting carved stones by 3D modelling – Example of Mongolian deer stones
Rock art studies are facing major technical challenges for extensive documentation. Nowadays, recording is essentially obtained from time-consuming tracing and rubbing, techniques that also require a high level of expertise. Recent advances in 3D modelling of natural objects and computational treatment of the modelled surfaces may provide an alternative, and reduce the current documentation bottleneck. The aim of this study is to examine the extent to which such treatments can be applied. The case study presented here concerns the famous deer stones erected by ancient Mongolian nomad populations. The 3D acquisition workflow is based on structure-from-motion, a versatile photogrammetric tech…
Machine learning for rapid mapping of archaeological structures made of dry stones – Example of burial monuments from the Khirgisuur culture, Mongolia –
11 pages; International audience; The present study proposes a workflow to extract from orthomosaics the enormous amount of dry stones used by past societies to construct funeral complexes in the Mongolian steppes. Several different machine learning algorithms for binary pixel classification (i.e. stone vs non-stone) were evaluated. Input features were extracted from high-resolution orthomosaics and digital elevation models (both derived from aerial imaging). Comparative analysis used two colour spaces (RGB and HSV), texture features (contrast, homogeneity and entropy raster maps), and the topographic position index, combined with nine supervised learning algorithms (nearest centroid, naive…
Application de la photogrammétrie à la documentation de l’art rupestre, des chantiers de fouilles et du bâti
During his archaeological missions the Museum of Prehistoric Anthropology tested the 3D modelling of several typesof objects. His team chose the ‘Structure-from-Motion’ (SfM) method which works according the basic principle of stereoscopicphotogrammetry, namely that 3D structure can be resolved from two or more overlapping, offset images. Most of other methodscapable of surveying, at high resolution, often complex objects and landforms are very expensive and have a difficult portability.Using only a consumer-grade digital camera and a scale on the ground, the user moves through the environment, acquiringphotographs of the area of interest from as many locations and perspectives as possible.…
Applications de la photogrammétrie à la documentation de l'art rupestre, des chantiers de fouilles et du bâti
Contextualization of archaeological information using augmented photospheres, viewed with head-mounted displays.
Photospheres, or 360°
Images of camels on a mammoth tusk from West Siberia
International audience; This study introduces the engravings on a mammoth tusk from the lower reaches of the Tom River in WestSiberia. The tusk was found in 1988 during construction works and was later transferred to the Tomsk StateUniversity, but it remained almost unknown to specialists until now. Radiocarbon dating by AMS reported theage of the tusk as 13,100–13,005 Сal BP (95% confidence level). The surface of the tusk is engraved with imagesof two-humped camels arranged in two pairs. In addition, arrows and wounds within the contours of the animalscan be seen. The comparative analysis of the stylistic features of the camel figures shows that they correspond tothe age of the tusk itself, …