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The paper introduces a method of prompt orthotransformation of space images, based on the integration of the orbital and polynomial methods of photogrammetric image processing. The concept of the method consists in fragmentary formation of an orthoimage. Fragments (quadrangles) of a definite size are marked in space images, so that geometric constraints between their elements are adequately described by a bidimensional polynom of the first order. The adjacent fragments have common vertexes on the contact line, providing integrity of the orthoimage being formed. The location of the fragment (the coordinates of its vertexes) is defined by the orbital method with consideration for the configuration of terrain, thus, if the fragment is small enough, it provides terrain correction for all the points of the fragment. To use the orbital method we define initial values of the orientation angles of the on-board equipment of the spaceship and the laws of variations of these angles in course of survey with subsequent specification of these values in terms of the coordinates of four check points. The compliance between tolerance points of fragments of the initial image and the image being formed is achieved on the basis of the models, the implementation of which is computationally less complex than that based on orbital methods. Experimental approbation of the proposed method proved that the method of prompt orthotransformation makes possible four-fold reduction of the time of photogrammetric space image processing while providing comparable accuracies of the resulting images.

This article analyzes the technology of creating and updating a digital topographic map using the method of mapping (generalization) on an updated map with a scale of 1 : 25;000 based on the source cartographic material. The main issue in the creation of digital maps is the study of map production accuracy and error analysis arising from the process of map production. When determining the quality of a digital map, the completeness and accuracy of object and terrain mapping are evaluated. The correctness of object identification, the logical consistency of the structure, the and representation of objects are assessed. The main and the most effective method, allowing to take into account displacement errors for the relief during image processing, is orthotransformation, but the fragment used to update the digital topographic map needs additional verification of its compliance with the scale requirements of the map. Instrumental survey will help to clearly identify areas of space image closer to nadir points and to reject poor quality material. The software used for building geodetic control network should provide stable results of accuracy regardless on the scale of mapping, the physical and geographical conditions of the work area or the conditions of aerial photography.

This article analyzes the technology of creating and updating a digital topographic map using the method of mapping (generalization) on an updated map with a scale of 1 : 25;000 based on the source cartographic material. The main issue in the creation of digital maps is the study of map production accuracy and error analysis arising from the process of map production. When determining the quality of a digital map, the completeness and accuracy of object and terrain mapping are evaluated. The correctness of object identification, the logical consistency of the structure, the and representation of objects are assessed. The main and the most effective method, allowing to take into account displacement errors for the relief during image processing, is orthotransformation, but the fragment used to update the digital topographic map needs additional verification of its compliance with the scale requirements of the map. Instrumental survey will help to clearly identify areas of space image closer to nadir points and to reject poor quality material. The software used for building geodetic control network should provide stable results of accuracy regardless on the scale of mapping, the physical and geographical conditions of the work area or the conditions of aerial photography. [ABSTRACT FROM AUTHOR]

Application of numerical technologies of digital image processing to the automation of crack pattern recording in brittle tensosensitive coatings is considered. The technique of orthotransformation of perspective pictures of crack patterns in tensosensitive coatings is described, which includes the following stages: the formation of a triangulation wireframe model of the structural element under study; selection of reference points for calculating the relative position of the object and camera at the photographing moment; determination of angular and spatial coordinates of the object position with respect to the camera; orthotransformation a separated area of a perspective image projection in the photograph; overlapping the orthotransformed image on the triangulation wireframe model of the structure under study. An example of application of the technique is shown for processing of the crack pattern in a brittle tensosensitive coating obtained during tensile testing of an aviation panel sample. Errors of distortions of linear and circular dimensions for the separated aviation panel element did not exceed 5% of actual values. [ABSTRACT FROM AUTHOR]