Image-based metric heritage modeling in the near-infrared spectrum

Abstract

Digital photogrammetry and spectral imaging are widely used in heritage sciences towards the comprehensive recording, understanding, and protection of historical artifacts and artworks. The availability of consumer-grade modified cameras for spectral acquisition, as an alternative to expensive multispectral sensors and multi-sensor apparatuses, along with semi-automatic software implementations of Structure-from-Motion (SfM) and Multiple-View-Stereo (MVS) algorithms, has made more feasible than ever the combination of those techniques. In the research presented here, the authors assess image-based modeling from near-infrared (NIR) imagery acquired with modified consumergrade cameras, with applications on tangible heritage. Three-dimensional (3D) meshes, textured with the non-visible data, are produced and evaluated. Specifically, metric evaluations are conducted through extensive comparisons with models produced with image-based modeling from visible (VIS) imagery and with structured light scanning, to check the accuracy of results. Furthermore, the authors observe and discuss, how the implemented NIR modeling approach, affects the surface of the reconstructed models, and may counteract specific problems which arise from lighting conditions during VIS acquisition. The radiometric properties of the produced results are evaluated, in comparison to the respective results in the visible spectrum, on the capacity to enhance observation towards the characterization of the surface and under-surface state of preservation, and consequently, to support conservation interventions.

[Retracted] Sculpture 3D Modeling Method Based on Image Sequence

“…When shooting the target, you can freely move the position of the camera and adjust the focal length of the camera as needed; since there is no need to calibrate the camera parameters in advance, the reconstruction result will not be affected by factors such as inaccurate calibration information or slight changes in camera parameters during the shooting process. Because the method calculates only the three-dimensional coordinates of all matching feature points, only sparse threedimensional spatial feature points can be reconstructed, so it is generally necessary to further reconstruct the three-dimensional model with the help of unique matching between images [19].…”

“…e traditional three-dimensional 3D model theory can accurately restore the 3D model of the object and can also adjust the light intensity and the selection of texture features artificially, so it has been widely used in mechanical manufacturing, construction engineering, game animation, etc. [5]. However, using this technology requires people who are very mature in the technology to perform manual operations, and the operability is poor, and it takes a long time to obtain three-dimensional information.…”

Joint development of cultural heritage protection and tourism: the case of Mount Lushan cultural landscape heritage site

“…Field surveys and mapping, photo files, and data collection are traditional methods of acquiring cultural heritage data, and these results have become an essential foundation for heritage protection [8]. Novel and advanced technologies, such as digital photogrammetry and spectral imaging, are becoming more widely employed in heritage science and are often used to comprehensively record, understand and protect historical relics and artworks [9]. Some examples of these advances include the use of drones to obtain high-resolution images and using the data for 3D modeling [10]; using 360 degrees panorama technology to obtain panoramic photos [11]; or using terrestrial laser scanners to obtain point clouds.…”

The Complex of Santa Croce in Ravenna as a Case Study: Integration of 3d Techniques for Surveying and Monitoring of a Historical Site

“…As said before, also a diagnostic analysis by thermal imaging (Adamopoulos, Bovero, & Rinaudo, 2020) was experimented in the interior. The used thermal camera was a FLIR P620, which has a spectral range between 7.5 μm and 13 μm, 640 x 800 resolution; the camera was equipped with the standard 24° lens.…”