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This paper presents a methodology for determining the position and speed of objects such as vehicles, pedestrians, or cyclists that are visible in video footage captured with only one camera. Objects are tracked in the video footage based on the change in pixels that represent the object moving. Commercially available programs such as PFTrack tm and Adobe After Effects tm contain automated pixel tracking features that record the position of the pixel, over time, two dimensionally using the video's resolution as a Cartesian coordinate system. The coordinate data of the pixel over time can then be transformed to three dimensional data by ray tracing the pixel coordinates onto three dimensional geometry of the same scene that is visible in the video footage background. This paper explains the automated process of first tracking pixels in the video footage, and then remapping the 2D coordinates onto three dimensional geometry using previously published projection mapping and photogrammetry techniques. The results of this process are then compared to VBOX recordings of the objects seen in the video to evaluate the accuracy of the method. Some beneficial aspects of this process include the time reduced in tracking the object, since it is automated, and also that the shape and size of the object being tracked does not need to be known since it is a pixel being tracked, rather than the geometry of the object itself. Concept of 2D Coordinate Transformation The tracking of objects in video, also called motion tracking, can be a manual or automated process where, in an x and y coordinate system determined by the video's resolution, a discrete pixel, or series of

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A Duna–Tisza közi homokhátságon időről időre vízgazdálkodási problémák jelennek meg. Ezek elsődleges kiváltó oka a részben antropogén hatásnak, részben pedig természeti folyamatoknak köszönhető talajvízszint-süllyedés. A talajvízszint-süllyedés a vizes élőhelyeken, mezőgazdasági és erdőgazdasági területeken egyaránt gondot okoz, és konfliktusokhoz vezet a tavak üzemeltetési kérdéseiben. Ezek a negatív hatások érintik a Kolon-tavat is, amely a Kiskunság kiemelt jelentőségű édesvízi mocsara. A Kolon-tó térségében jelentkező vízhiány távlatilag öntözési szükségleteket támaszthat a tó vízgyűjtőjén. Az ilyen irányú hatásokat próbáljuk előre jelezni a vízgyűjtőjére készített hidrodinamikai modell segítségével. A tárgyi modellvizsgálatok célja annak feltárása, milyen várható hatást gyakorol ezen a területen a vízszintpotenciál-eloszlásra, ha azzal számolunk, hogy a talajvízkészletet érintő rendszeres öntözési vízkivételre kerül majd ott sor.

<p>According to the climate change and Water Framework Directive 2000/60/EC (WFD) the analysis od the status of waterbodies and their continuous monitoring has to be carried out based on unified methodologies and standards. Individual prescriptions have to be in harmony with national and international standards, in order to ensure equal scientific value and comparability of the data. The international standard EN ISO 748 entitled „Hydrometry - Measurement of liquid flow in open channels using current-meters or floats” was issued in 2008. This standard is based on the discharge measurement methods in the European Union (EU) and it differs in some aspects from the Hungarian standard (ME-10-231-16:2009). The goal of our study was to identify and answer the questions related to the introduction of this standard into Hungarian practice. The issue is crucial for the hydrometry units of Hungarian Water Directorates, as if the introduction of a new standard is not correctly substantiated the consequences can include avoidable economical burdens and/or changes in the quality of data. The research was initiated and financed by the Hungarian General Directorate of Water management and targeted at the comparative analysis of the measurement and calculation methodologies of the two standards, carried out on watercourses in Hungary. Thus we have executed a series of measurements in 31 cross-sections on 18 different watercourses in Hungary. Based on our results we can state that the difference between the results of the different methodologies generally does not exceed the uncertainties originating from the measurements themselves. Under specific circumstances (e.g. very low flow velocities) the effect of the chosen methodology can be significant.</p>