Appl. Sci. 2023 , 13 , 1389
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The coordinate sets of the points of the detected edges and corners were input informa- tion to the algorithm for the analysis of image data. The image coordinates were converted to metric coordinates (mm) based on information about the spatial resolution of the images and the arbitrarily assumed place of the beginning of the coordinate system (associated with the place where the sample is handled in a still holder). The shape of the edge of the test sample in subsequent images of the recorded sequence is shown in Figure 7.
Figure7. An example of the shape of the edge of the sample being tested in subsequent images of the recorded sequence. The apparent movement of the lower end of the sample edge is the result of limiting the analysis field to the area of correct edge detection in the image. The assumed origin of the coordinate system, associated with the edge of the still handle, is below the bottom edge of the image. 2.4. Synchronization of Image Data and Measurement Results from the Testing Machine The average values of the coordinates of the corners of the movable and stationary checkerboard were used to determine the displacement of the handle at the moments of recording individual photos. Based on this information, the time of photo recording as a function of the time of measurement data acquisition in the testing machine was estimated, as shown in Figure 8. The result was the synchronization of data recording times from two different sources.
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