3.2 Modelling for Videos
The major difference between images and videos is the possible object movement in the temporal axis. In fact, visual attention modelling is more meaningful for videos than still images. The perception of still images varies with the allowed observation time. That is, if an observer has a long enough time to perceive an image, every point of the image can become the attention centre eventually. The perception of video is different. Every video frame is displayed to an observer within a limited time interval, which is determined by the frame rate. Furthermore, motion causes the viewer to pay attention to the moving part and triggers subsequent eye movement. In this section, we will first discuss a simple extension of the BS model introduced in Section 3.1 for video scenario (as Section 3.2.1). Then the computation of the motion feature is presented in Section 3.2.2, and the introduction of an alternative visual attention formulation is given in Section 3.2.3, which allows the consideration of overlapping among different features appearing in the visual signal simultaneously, as well as interaction of salient locations and smooth transition.
3.2.1 Extension of BS Model for Video
Humans are interested in moving object in a static environment: a moving boat on a calm sea or a moving car in the street and so on, often attract the observer's attention, and so motion is a very important feature in the video attentional model. In principle, the BS model illustrated ...