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50     2  Basic Relations: Image Sequences – “the World”


            1. Recursive estimation as used in this approach starts from the values of the state
              variables predicted for the next time of measurement taking.
            2. Deeper  understanding  of temporal processes results from having  representa-
              tional terms available describing these processes or typical parts thereof in sym-
              bolic form,  together with  expectations  of motion behavior over  certain  time-
              scales.
              A typical example is the maneuver of lane changing. Being able to recognize
            these types of maneuvers provides more certainty about the correctness of the per-
            ception process. Since everything in vision has to be hypothesized from scratch,
            recognition of processes on different scales simultaneously helps building trust in
            the hypotheses pursued. Figure 2.17 may have been the first result from hardware-
            in-the-loop simulation where a technical vision system has determined the input



                    25

                                       Start

                                  237          50
                                        0
                                               Time
                              R = 1/C          step
                        197         0                         90
                    15                        number
                  x / m
                                     157        130

                    10


                                                           y / m
                     5
                     -15    -10     -5      0      5      10    15
                                         x  c
                  Bird’s eye view
                     on track      Camera       y c
                                   position











             Figure 2.17. Changing aspect conditions and edge feature distributions while a simu-
             lated vehicle drives on an oval track with gaze fixation (smooth visual pursuit) by a sta-
             tionary  camera. Due to continuity conditions  in 3-D space  and time, “catastrophic
             events” like feature appearance/disappearance can be handled easily.
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