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The development of modern surveying methods, particularly, Terrestrial Laser Scanning (TLS), has found wide application in protecting and monitoring engineering and objects and sites of cultural heritage. For this reason, it is crucial that several factors a˛ecting the correctness of point cloud registration are considered, including the correctness of the distribution of control points (both signalised and natural), the quality of the process, and robustness analysis. The aim of this article is to evaluate the quality and correctness of TLS registration based on point clouds converted to raster form (in spherical mapping) and hand-crafted detectors. The expanded Structure-from-Motion (SfM) was used to detect the tie points for TLS registration and reliability assessment. The results demonstrated that affine detectors are useful in detecting a high number of key points (increased for point detectors by 8–12 times and for blob detectors by about 10–24 times), improving the quality and TLS registration completeness. For the registration accuracy of point cloud on signalised check points, the lower values can be noted for maximum RMSE errors for blob affine detectors than detectors and larger values for corner detectors and affine detectors (not more than 4 mm in the extreme cases, typically 2 mm). The commonly-applied target-based registration method yields similar results (di˛erences do not exceed – in extreme cases – 3.5 mm, typically less than 2 mm), proving that using affine detectors in the TLS registration process is and reasonable and can be recommended.

Projection of a complicated geometry of industrial objects is the complex issue, which requires properly planned and prepared measurements. Such objects must be accurately inventoried, but their complicated nature often makes the access and the visibility of their entire surface very difficult. Documentation of measurements is often prepared in the form of sketches, plans or maps, which are amended with photographic documentation. The objective of this paper is to test the possibilities to apply laser scanning and the network of digital images for inventory and monitoring of technical conditions of industrial objects. Processing of a precise documentation acquired basing on terrestrial laser scanning data or dense points clouds generated from digital images still causes many difficulties and problems. Although data processing algorithms have been intensively developed with respect to generation of high resolution orthoimages or precise vector drawings, the existing problems are still connected with limitations related to imperfections of both techniques of measurements.

In this research, the issues related to processing and analysis of the images, acquired by the lowcost terrestrial sensors and an unmanned aerial vehicle (UAV) of the archaeological sites in an urban environment placed in area of Kutaisi, Georgia, have been considered. Taking into account generation of the Bagrati site photogrammetric documentation, the low-cost UAV DJI Phantom 3 and Pentax SLR camera, were chosen. Due to the geometrical and radiometric parameters of the chosen sensors, an extended methodology of UAV and terrestrial data processing in Agisoft PhotoScan was proposed. This task solution was enabled by application programming interface API (which allowed taking advantage of software functions - not available in the basic version of the program) and additionally the script written in MatLab software by authors. The method of processing, filtrating, eliminating and weighting of the measurement observations in the bundle adjustment process was proposed. As a result of performed works, the accuracy of the results of the bundle adjustment, increased significantly in comparison to the raw data. Furthermore, statistical data analysis had been expanded. [ABSTRACT FROM AUTHOR]

Generation of precise and, at the same time, high resolution architectural documentation, acquired on the basis of terrestrial laser scanning or dense point clouds from digital images is still and open issue, which forms many challenges. Today, close range photogrammetry has great potential for development through the use of low-cost image acquisition tools. Mobile phones, digital camcorders or compact cameras are all sources of data, which potentially allow for the creation of reliable and accurate three-dimensional models of analysed scenes. This paper presents the results of a comparison between these aforementioned sources of image information, acquired by simple and popular cameras, and data acquired from a close range laser scanner. These sets of photos produced several virtual models of small architectural details, supported by Agisoft software. A final rating was conducted using data acquired for the same object using a laser scanner, which was taken as a referential approximation of the three-dimensional shape. [ABSTRACT FROM AUTHOR]

The presented paper shows the diversity of photogrommetric approaches by introducing a problem of camera interior orientation, data georeferencing. data integration and the issue of automatic object surface modelling. The authors discuss the abovementioned issues on the example of the work carried out at the Faculty of Geodesy and Cartography, Warsaw University of Technology referring to solutions practiced in Computer Vision. This article is an example of introduction of photogrammetry as a discipline open to achievements of close fields of science, which is widely applied in practice [ABSTRACT FROM AUTHOR]