Multispectral Imaging in Cultural Heritage Conservation

Abstract

ABS TRACT:This paper sums up the main contribution derived from the thesis entitled "Multispectral imaging for the analysis of materials and pathologies in civil engineering, constructions and natural spaces" awarded by CIPA-ICOM OS for its connection with the preservation of Cultural Heritage. This thesis is framed within close-range remote sensing approaches by the fusion of sensors operating in the optical domain (visible to shortwave infrared spectrum). In the field of heritage preservation, multispectral imaging is a suitable technique due to its non-destructive nature and its versatility. It combines imaging and spectroscopy to analyse materials and land covers and enables the use of a variety of different geomatic sensors for this purpose. These sensors collect both spatial and spectral information for a given scenario and a specific spectral range, so that, their smaller storage units save the spectral properties of the radiation reflected by the surface of interest. The main goal of this research work is to characterise different const ruction materials as well as the main pathologies of Cultural Heritage elements by combining active and passive sensors recording data in different ranges. Conclusions about the suitability of each type of sensor and spectral range are drawn in relation to each particular case study and damage. It should be emphasised that results are not limited to images, since 3D intensity data from laser scanners can be integrated with 2D data from passive sensors obtaining high quality products due to the added value that metric brings to multispectral images.

Review of Methods for Documentation, Management, and Sustainability of Cultural Heritage. Case Study: Museum of King Jan III’s Palace at Wilanów

“…In order to identify the materials forming the object, different classification algorithms are used. It is a common practice to use supervised and unsupervised classification strategies interchangeably [123]. Classes detected in laboratory conditions may serve as pigment libraries [124], which may be then used as reference for further field work [115,125,126].…”

“…Many works prove the usefulness of multi-and hyperspectral imagery in this field. Integration of two cameras (including a multispectral one) and TLS data operating in different wavelengths was proved to provide spectral data allowing for generation of moisture classification map [123]. As the range between 1.4 um and 1.9 um is considered as "water absorption bands" [114], SWIR (shortwave infrared) sensors operating in this wavelength may also be used for this purpose.…”

The Multitemporal Photogrammetric Data in Archaeological and Architectural Research in the Royal Castle in Warsaw – First Results

“…For that purpose methods of 3D shapes measurements are applied, basing on active and passive techniques (Arif and Essa, 2017;Grussenmeyer and Yasmine, 2004;Hatzopoulos et al, 2017;Markiewicz et al, 2017;Remondino and El-hakim, 2006) Selection of an appropriate measurement techniques determines the way of data acquisition and processing as well as development of documentation. Both, the active (TLS) and passive (imagebased approach) techniques have their advantages and disadvantages (Gonizzi Barsanti et al, 2013 Barsanti et al, 2013) Nowadays, research works concerning the Cultural Heritage and archaeology utilise integration of many techniques, including aerial and UAV (Arif and Essa, 2017;Del Pozo et al, 2017;Grussenmeyer and Yasmine, 2004;Koistinen, 2004;Murtiyoso et al, 2017;Nocerino et al, 2012;Sauerbier and Eisenbeiss, 2010), LIDAR -ALS and TLS (Arif and Essa, 2017;Del Pozo et al, 2017;Drap et al, 2007;Gonizzi Barsanti et al, 2013;Grussenmeyer and Yasmine, 2004;Hatzopoulos et al, 2017;Markiewicz et al, 2017), as well as close-range photogrammetric (Gonizzi Barsanti et al, 2013;Grussenmeyer and Yasmine, 2004;Hatzopoulos et al, 2017;Remondino and El-hakim, 2006). For the purposes of discussed analyses the authors used UAV, terrestrial and low-cost photographs and TLS data were used as reference data.…”

Seamless Co-Registration of Images From Multi-Sensor Multispectral Cameras

“…With the advancement of digital imaging technologies, multispectral cameras have been developed in small formats at prices affordable by a wide range of end-users. These cameras have, thus, become popular in applications such as wildlife monitoring, forestry, precision agriculture, heritage documentation, disaster management, and even visual odometry (Albetis et al, 2019;Beauvisage et al, 2017;Candiago et al, 2015;Chen et al, 2018;Crutsinger et al, 2016;Dash et al, 2017;Del Pozo et al, 2017;Hassan et al, 2019;Munawar et al, 2019;Wang and Thomasson, 2019).…”