Bence Molnár

Budapest University of Technology and Economics · Department of Photogrammetry and Geoinformatics

Circadian leaf movements are widely known in plants, but nocturnal movement of tree branches were only recently discovered by using terrestrial laser scanning (TLS), a high resolution three-dimensional surveying technique. TLS uses a pulsed laser emitted in a regular scan pattern for rapid measurement of distances to the targets, thus producing thr...

Environmental, engineering and industrial modelling of natural features (e.g. trees) and man-made features (e.g. pipelines) requires some form of fitting of geometrical objects such as cylinders, which is commonly undertaken using a least-squares method that—in order to get optimal estimation—assumes normal Gaussian distribution. In the presence of...

Steep, and hardly accessible jointed rhyolite tuff cliff faces surround a Castle in NE-Hungary, at village of Sirok. The assessment of cliff stability required the recording of cliff geometry. Traditional surveying was not possible therefore cliff faces were 3D modelled by GNSS supported terrestrial laser scanner and UAV. The onsite engineering geo...

Surface reconstruction from point clouds generated by laser scanning technology has become a fundamental task in many fields of geosciences, such as robotics, computer vision, digital photogrammetry, computational geometry, digital building modelling, forest planning and operational activities. Point clouds produced by laser scanning, however, are...

Web-based photo albums that support organizing and viewing the users’ images are widely used. These services provide a convenient solution for storing, editing and sharing images. In many cases, the users attach geotags to the images in order to enable using them e.g. in location based applications on social networks. Our paper discusses a procedu...

Web-based photo albums that support organizing and viewing the users’ images are widely used. These services provide a convenient solution for storing, editing and sharing images. In many cases, the users attach geotags to the images in order to enable using them e.g. in location based applications on social networks. Our paper discusses a proced...

Pedestrian flow is much less regulated and controlled compared to vehicle traffic. Estimating flow parameters would support many safety, security or commercial applications. Current paper discusses a method that enables acquiring information on pedestrian movements without disturbing and changing their motion. Profile laser scanner and depth camera...

Pedestrian flow is much less regulated and controlled compared to vehicle traffic. Estimating flow parameters would support many safety, security or commercial applications. Current paper discusses a method that enables acquiring information on pedestrian movements without disturbing and changing their motion. Profile laser scanner and depth camera...

Siroki várhegyet alkotó riolittufa állékonysági vizsgálatát mutatja be a cikk, kiemelve a térinformatika és a mérnökgeológia együttes alkalmazását. A sziklalejtő felmérésére az erősen tagolt domborzat miatt és a nehéz megközelíthetőség miatt GNSS támogatású földi lézerszkennelés és drónos légifényképezést alkalmaztunk. Az így kapott térinformatikai...

In this paper, the use of waveform data in urban areas is studied. Full waveform is generally used in non-urban areas, where it can provide better vertical structure description of vegetation compared to discrete return systems. However, waveform could be potentially useful for classification in urban areas, where classification methods can be exte...

This notebook presents different techniques to estimate radius and position of a sphere in case of quantized depth information obtained from low resolution sensors like Microsoft Kinect XBOX. First algebraic, geometric and directional least squares estimations were applied to the quantized data directly. Then two techniques Self-Organizing Map (SOM...

MS Kinect, a motion sensor, developed as a game console for the XBOX360, is a Flash-LiDAR-type sensor. Earlier investigations have confirmed that good accuracy can be achieved with that inexpensive device. As the returned depth image is coarsely quantized and the spacing of the points is growing with the object distance, the accuracy degrades at la...

The Microsoft Kinect sensor, a popular gaming console, is widely used in a large number of applications, including close-range 3D measurements. This low-end device is rather inexpensive compared to similar active imaging systems. The Kinect sensors include an RGB camera, an IR projector, an IR camera and an audio unit. The human morphologic measure...

Full Waveform Data (FWD) has been increasingly becoming available on modern airborne LiDAR systems. Since the waveform signal is noisy and rather sparse by nature, the compressed FWD representation has several advantages. First, the reduced data volume makes the storage and transmission of waveform data faster and more economic. Second, the sparse...

Flash LiDAR systems have been around for several years, but their use was limited, mainly due to their poor performance. The first generation products had range limitations and were quite sensitive to ambient light conditions, basically restricting their use to indoor applications. In addition, the high-noise level provided for very low accuracy an...

This paper provides an update on the continuing research effort focused on creating a collaborative navigation solution of various multi-sensory platforms for indoor, outdoor, and transitional environments. The emphasis of this paper is to investigate the usefulness of 3D imagery, taken from optical or laser sensors, in aiding indoor cooperative na...

With the appearance of digital cameras photogrammetry entered a new era. Simple digital cameras emerged and new methods of three-dimensional measurements became available (e.g. lasers-scanner) in addition to the basic methods of photogrammetry. Cost plays major role in development of new methods. At the same time new user requirements emerge: apply...

3D photogrammetric processing of images taken by commercial digital cameras would be remarkably beneficial for the wide public. Equipment and techniques are available; the only missing component is an affordable software that can be widely accessed. To fulfill this demand, a web-based photogrammetry suit was developed that runs in a web browser. In...