STRUCTURE FROM MOTION PROCESSING OF ANALOGUE IMAGES CAPTURED BY ROLLEI METRIC CAMERA, DIGITIZED WITH VARIOUS SCANNING RESOLUTION

SfM processing of archived analogue images gives an opportunity to efficiently create new and valuable 2D and 3D results. The SfM processing of digitized analogue images brings some challenges. How to digitize negatives of photogrammetric images? What scanning resolution is the most beneficial for processing? How to preprocess the digitized images to be able to process them using the SfM method? What accuracy of results is possible to expect? This paper tries to deal with all these questions. For this paper, 7 negatives of former photogrammetric documentation of a vault were chosen. The negatives were captured by Rollei 3003 metric camera in 1999. Two pieces of software were chosen for the SfM processing. A commercial alternative Agisoft PhotoScan and free open-source alternative MicMac. The results of the SfM processing were compared to the results of an original photogrammetric method, which was used for former processing in 1999

Photogrammetric Co-Processing of Thermal Infrared Images and RGB Images

In some applications of thermography, spatial orientation of the thermal infrared information can be desirable. By the photogrammetric processing of thermal infrared (TIR) images, it is possible to create 2D and 3D results augmented by thermal infrared information. On the augmented 2D and 3D results, it is possible to locate thermal occurrences in the coordinate system and to determine their scale, length, area or volume. However, photogrammetric processing of TIR images is difficult due to negative factors which are caused by the natural character of TIR images. Among the negative factors are the lower resolution of TIR images compared to RGB images and lack of visible features on the TIR images. To eliminate these negative factors, two methods of photogrammetric co-processing of TIR and RGB images were designed. Both methods require a fixed system of TIR and RGB cameras and for each TIR image a corresponding RGB image must be captured. One of the methods was termed sharpening and the result of this method is mainly an augmented orthophoto, and an augmented texture of the 3D model. The second method was termed reprojection and the result of this method is a point cloud augmented by thermal infrared information. The details of the designed methods, as well as the experiments related to the methods, are presented in this article

Transformations in the Photogrammetric Co-Processing of Thermal Infrared Images and RGB Images

The photogrammetric processing of thermal infrared (TIR) images deals with several difficulties. TIR images ordinarily have low-resolution and the contrast of the images is very low. These factors strongly complicate the photogrammetric processing, especially when a modern structure from motion method is used. These factors can be avoided by a certain co-processing method of TIR and RGB images. Two of the solutions of co-processing were suggested by the authors and are presented in this article. Each solution requires a different type of transformation–plane transformation and spatial transformation. Both types of transformations are discussed in this paper. On the experiments that were performed, there are presented requirements, advantages, disadvantages, and results of the transformations. Both methods are evaluated mainly in terms of accuracy. The transformations are presented on suggested methods, but they can be easily applied to different kinds of methods of co-processing of TIR and RGB images

Monitoring of crop fields using multispectral and thermal imagery from UAV

In the following paper, an application of Unmanned Aerial Vehicle (UAV) for agricultural purposes will be presented. The field of interest to be monitored is situated in the Western part of the Czech Republic. It is located in the area of the Vysoké Sedliště village, close to the city of Planá. There are two main crops cultivated in the area – corn and barley. The surrounding territory is mostly covered with grass. The research team carried out numerous unmanned flights with a fixed-wing platform with two different sensors – multispectral and thermal. Three vegetation indices were computed. Moreover, two thermal maps are presented to indicate the relation between vegetation and soil temperature

From Analogue to Digital Photogrammetry: Documentation of Padise Abbey in Two Different Time Stages

Exploration of historical buildings during their life cycles is one of many aspects of the cultural heritage research. For studying different conditions of historical buildings over time, it is convenient to use photogrammetric surveys carried out in different time stages. Modern photogrammetric methods give the possibility to use archived analogue photogrammetric data, re-process them, and achieve new potentially valuable results with sufficient geometric accuracy and with high visual quality. The paper presents re-processing of analogue archival photogrammetric images captured by a metric camera in 1991 and compares the results to the new photogrammetric survey with a digital camera. The object of interest is Padise Abbey in Estonia. In 1991, parts of the abbey were in poor condition and conservation and renovation works were at an early stage. Nowadays, the abbey is partly renovated, and the results of the new photogrammetric survey give an opportunity to study two completely different conditions