Studienteilnehmer gesucht

Das MPI für biologische Kybernetik sucht für einige seiner wissenschaftlichen Experimente Studienteilnehmer Öffnet einen internen Link im aktuellen Fenster[mehr].

Aktuellste Publikationen

Zaretskaya N, Fischl B, Reuter M, Renvall V und Polimeni JR (Januar-2018) Advantages of cortical surface reconstruction using submillimeter 7 T MEMPRAGE NeuroImage 165 11-26.
Venrooij J, Mulder M, Mulder M, Abbink DA, van Paassen MM, van der Helm FCT und Bülthoff HH (Dezember-2017) Admittance-Adaptive Model-Based Approach to Mitigate Biodynamic Feedthrough IEEE Transactions on Cybernetics 47(12) 4169-4181.
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Liu Y, Rajappa S, Montenbruck JM, Stegagno P, Bülthoff HH, Allgöwer F und Zell A (Dezember-2017) Robust nonlinear control approach to nontrivial maneuvers and obstacle avoidance for quadrotor UAV under disturbances Robotics and Autonomous Systems 98 317-332.
Paech D, Schuenke P, Koehler C, Windschuh J, Mundiyanapurath S, Bickelhaupt S, Bonekamp D, Bäumer P, Bachert P, Ladd ME, Bendszus M, Wick W, Unterberg A, Schlemmer HP, Zaiss M und Radbruch A (Dezember-2017) T1ρ-weighted Dynamic Glucose-enhanced MR Imaging in the Human Brain Radiology 285(3) 914–922.
Pavlova MA, Erb M, Hagberg GE, Loureiro J, Sokolov AN und Scheffler K (November-2017) "Wrong Way Up": Temporal and Spatial Dynamics of the Networks for Body Motion Processing at 9.4 T Cerebral Cortex 27(11) 5318–5330.

 

Für die Aufnahmen von Gesichtern und allgemein von Bewegungen haben wir zwei spezielle Labore: Das VideoLab ist auf die Aufnahmen von menschlichen Tätigkeiten aus mehreren Blickfeldern ausgelegt.

Sechs Kameras können genau synchronisierte Farbenvideos aufnehmen und mit Audioaufnahmen abgleichen. Mit dem VideoLab wurde z.B. eine große Öffnet einen externen Link in einem neuen FensterDatenbank von Gesichtsausdrücken erstellt. Diese Datenbank wird wiederum in mehreren Projekten, wie zum Beispiel bei Untersuchungen zur Gesichtserkennung oder zur Kommunikation mit Gesichtsausdrücken eingesetzt.

Im ScanLab werden moderne 3D Scanner verwendet, um Form- und Farbinformation von Gesichtern und Gesichtsausdrücken aufzunehmen – unser neuester Scanner kann dies sogar mit Videogeschwindigkeit, ist also ein 4D Scanner. Diese Aufnahmen werden dann direkt in psychophysikalischen Experimenten verwendet oder für den Einsatz in Computeranimationen weiterverarbeitet.

Das VideoLab

Das VideoLab, das seit Mai 2002 in Benutzung ist, wurde für die Aufnahme menschlicher Bewegungen aus mehreren Ansichten entwickelt. It currently consists of 6 Basler CCD cameras that can record precisely synchronized color videos. In addition, the system is equipped for multi-angle audio recording that is synchronized to the video data. The whole system was built from off-the-shelf components and was designed for maximum flexibility and extendibility. The VideoLab has been used to create a database of facial expressions and action units (http://vdb.kyb.tuebingen.mpg.de/) and is being employed in several projects on recognition of facial expressions and gestures across viewpoints, multi-modal action learning and recognition, as well as in investigations of visual-auditory interactions in communication.

One of the major challenges in creating the VideoLab consisted of choosing hardware components allowing for on-line, synchronized recording of uncompressed video streams. Each of the 6 Basler A302 bc digital video cameras produces up to 26 MB per second (782 × 582 pixels at 60 frames per second) – date that is continuously written onto the hard disk. Currently, the computers have a striped RAID-0 configuration with a total disk capacity of 200 GB each to maximize writing speed. The computers are connected and controlled via a standard Ethernet- LAN. As there was no commercial software available for control of multi-camera recording setups, we had to develop our own distributed recording software. In addition to the frame grabber drivers, which provide basic recording functionality on a customized Linux operating system, we programmed a collection of distributed, multi-threaded real-time C programs that handle control of the hardware, as well as buffering and write-out of the video- and audio data to hard discs. All software components communicate with each other via standard Ethernet-LAN. On top of this control software, we have implemented a graphical user interface with which one can access the whole functionality of the VideoLab.
This image shows an example recording of the VideoLab (Facial expression recorded from 6 synchronized viewpoints)

ScanLab

Left: ABW scanner setup. Right: Sample data of the ABW structured light scanner

Several commercial 3D scanning systems are used for capturing shape and color information of faces. The data is used for producing stimuli for psychophysical experiments and for building models to support machine learning and computer vision algorithms:

Cyberware Head Scanner
This scanner (Cyberware, Inc., USA), uses laser triangulation for recording 3D data and a line sensor for capturing color information, both producing 512 x 512 data points (typical depth resolution 0.1 mm), covering 360º of the head in a cylindrical projection within 20 s. It was extensively used to build the MPI Head Database (Öffnet einen externen Link in einem neuen Fensterhttp://faces.kyb.tuebingen.mpg.de/).

ABW Structured Light Scanner
This is a customized version of an industrial scanning system (ABW GmbH, Germany), modified for use as a dedicated face scanner. It consists of two LCD line projectors, three video cameras and three DSLR cameras. Using structured light and a calibrated camera/projection setup, 3D data can be calculated from the video images using triangulation. Covering a face from ear to ear, the system produces up to 900.000 3D points and 18 megapixels of color information. One recording takes about 2 s, thus making this scanner much more suitable for recording facial expressions. It was used extensively for building a facial expression model and for collecting static FACS data.

ABW Dynamic Scanner
Using the same principle of structured light, this system uses a high-speed stripe pattern projector, two high-speed video cameras and a color camera synchronized to strobe illumination. It can currently perform 40 3D measurements/s (with color information), producing detailed face scans over time. Ten seconds of recording time produce 2 GB of raw data.

3dMD Speckle Patter Scanner
This turn-key system (3dMD Ltd, UK) is mainly designed for medical purposes. Using four video cameras in combination with infrared speckle pattern flashes and two color cameras in sync with photography flashes, it can capture a face from ear to ear in 2 ms, making it highly suitable for recording infants and children. This system is used in collaboration with the University Clinic for Dentistry and Oral Medicine for studying infant growth.

Passive 4D Stereo Scanner
With three synchronized HD machine vision cameras (two grayscale, one color), this system (Dimensional Imaging, UK) is capable of reconstructing high-quality dense stereo data of moving faces at a rate of 25 frames/s. Since it is a passive system, high-quality studio lighting can be used to illuminate the subject which results in better color data as well as more subject comfort, compared to the ABW Dynamic Scanner. While care must be taken with focus, exposure and calibration of the cameras, the system imposes fewer limitations on rigid head motion.

 
Last updated: Freitag, 14.10.2016