Morphological tools for indexing video documents

This paper proposes a local algorithm using morphological operators, which leads to several useful tools for indexing video documents. It consists of a local computation of a similarity criterion between two successive frames of a sequence, followed by the study of the temporal evolution curve of this criterion for the whole sequence. From this curve, shot transitions are extracted by means of a powerful morphological filter, the inf top-hat. At this point, we have built a cut detection tool. The local computation together with strong morphological filtering leads to a very simple, fast and computationally efficient algorithm, with a high detection rate in the case of cuts for a small level of false detections. This algorithm also gives access to a spatial model of the transition and to a selection of key frames for each shot. By applying the local similarity measure to the key frames, two other tools are built to detect inner shot changes and syntactically related shots. Finally, the relation detection is used in a newscaster detection tool.