Terms qa decryption railway transport data using digital aerial photography

Objective. The aim of this study is a reasonable definition of the conditions which must be satisfied for digital aerial image for high-quality recognition objects of rail transport with the aim of creating a plan with scale of 1:500, and the experimental study of the quality of rail transport objects interpretation on digital aerial images. Method and results. For inventory of land and rail transport objects based on the use of digital aerial survey it is necessary to ensure receiving  of quantitative and qualitative characteristics of the objects that meet the requirements of the branch. In this paper there were obtained formulas for calculation of the basic parameter of digital aerial survey - coefficient that determines the ratio of a scale of image to a scale of topographic plan. Here at the size of the pixel in the image plane, and the distance between adjacent pixels (GSD) are taken into account. The analysis of some features of the most known and consumed digital aerial cameras of matrix and scanner types is implemented. Experimental researches of quality of interpretation of about 50 categories of objects related to railroad on digital aerial images obtained with UltraCam camera in scale 1:3000 were done. It is established that quality of interpretation meets requirements for creation a plan of the railway in scale 1:500. Scientific novelty. It is substantiated the expediency of creating high-precision components for cartographic mapping and inventory of land and objects of railway transport, which provides a solution to problems of reconstruction, construction, maintenance and inventory , i.e. main areas of functioning and development of the railway. The basic parameters for digital aerial survey for precision mapping of railroad objects are substantiated. The conditions, which provide qualitative interpretation of objects of the railway on digital images are determined. The practical significance. The practical significance of the results is that for comprehensive inventory railroad mapping it is suggested to use precision digital aerial survey, which allow avoiding dubbing in such works and provides the strategic tasks of the branch development. All elements of the proposed approach and technology are developed to logical conclusion and tested on a real material. Therefore, they can be recommended for the use of railway units in Ukraine.