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ptv manual
  108 References Appendix A.1 Handling of the 3D PTV software Techniques of digital photogrammetry are suitable for static applications as well as for 3Dmeasurement tasks in dynamic processes (El-Hakim, 1986). 3D PTV can be considered atypical application field of digital photogrammetric techniques (Grün, 1994). The method requires the acquisition and processing of stereoscopic, synchronized image sequences of themoving particles.In the following sections a step by step advice for running PTV, some information on the input/output files is given. A.2 Running the 3D PTV software under different operation systems The source code of the PTV software is written in C, Tcl/Tk is required for the graphical user interface (GUI). The software can be compiled on any operation system where C and Tcl/Tk isavailable. The current PTV implementation runs under UNIX as well as Windows operatingsystems. For the image sequence data acquisition PCs with Windows operation system areused. The GUI is implemented with Tcl/Tk (current version is 8.4.2, released in march 2003,(Tcl, 2003)), which is freely available for Windows and UNIX platforms. Considering thatmost potential PTV users might only work with one of the mentioned operating system, the portability also could contribute to an easy distribution of the developed PTV method. A.3 Parameter files for 3D PTV Before running PTV, several parameter files (in ASCII) have to be created in a subdirectory of the project directory, it has to be called   parameter   and must contain the following files: ptv.par main parameter filecriteria.par object volume and correspondences parameterssequence.par sequence parameterstarg_rec.par parameters for particle detectioncal_ori.par calibration plate, images, orientation filesdetect_plate.par parameters for control point detectionman_ori.par point number for manual pre-orientationorient.par flags for camera parameter usagetrack.par tracking parameterssortgrid.par sortgrid parameter  pft_version flag for peak fitting versionFor storing of the results a directory named   res  should exist. Working with PTV the Tcl/Tk-GUI allows editing parameter files, to process a single time step or whole sequences. As a preparing steps a calibration of the image acquisition system is required. The main window isshown in Fig. 61. Each processing step can be started from the task bar, the processing statusand the actual mouse button functions are displayed in the information window below. With  109 References  Start   the project parameters are loaded from the input files and additional windows for thedisplay of the images for each camera are opened.The settings for the PTV processing can beedited through three different parameter windows(to be opened under the submenu  Change Parameters , shown in Fig. 62). The windows for the editing of the parameters can be found under  Change Main Parameters  (shown in Fig. 63), Change Calibration Parameters  (Fig. 64) and  Change Tracking Parameters  (Fig. 69). Fig.61: Main window of PTV softwareFig.62: Submenu Change Parameters  110 References A.4 Data Input The processing of image data with PTV requires for each camera a valid video sequence stored in TIFF- (8 Bits/Sample, single image plane) or as raw data files. The respective flag for TIFFor raw file must be set. The filename for the sequence image is a combination of a basename Fig.63: Main parameter window  111 References indicating the camera and a current number. For each camera an orientation data file ( name.ori )and an additional parameters file ( name.addpar  ) must exist and has to be accessible for PTV.Examples for the parameterfiles: ptv.par: main parameter file 4number of camerascam3.100image of first camerakal1calibration data of first cameracam0.100image of second camerakal3calibration data of second camera Fig.64: Calibration parameter window
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