Publication, Research, Docs and Info, KAMEDA

next up previous
Next: Experiment Up: Control and Selection Previous: Automatic Camera Control

Automatic Camera Selection Rule

There are generally several criteria to define video clip (cut). From our experience, we think people want to see moving objects rather than static objects. And, as more important insight, we think people prefer to see an object which just starts moving rather than an object which keeps moving.

So, in our approach, each observation camera sends a request to video selector to select one of the shoot cameras it is controlling when it detects movement of an object. Once after the movement is detected and send the request, it will not send a selection request while the object keeps moving. To detect the beginning of the movement, we introduce time parameter for an observation camera i. Suppose a movement is detected on the camera i. In this case, the camera i does not recognize the beginning of new movement unless there is a no-motion period longer than seconds. An example of video selection function is shown in Figure 3. In this example, there are 4 observation cameras. The horizontal axes mean time flow, and the vertical axes indicate motion detection level at each observation camera. A grey arrow indicates a selection request. If the motion detection level comes higher than certain threshold value, the request is generated. In the middle of the sequence in Figure 3, the camera No.4 cannot generate a request after the video of the camera No.3 is selected because the beginning of the second movement is too close (smaller than ) to the end of the previous movement.

Figure 3: Video Selection

Yoshinari Kameda
Tue Oct 5 01:12:48 JST 1999