Abstract
In this thesis, we will develop a video query by examples (QBE) operation for video database system based on the analysis and description of the spatio-temporal characteristics of the video sequences. Our system uses the characteristic of the video shot to retrieve similar shots in the database based on the video indices, and we processes the video shots to generate three hierarchical information: color, and motion, and object. First. We use Schunck method to estimate the motion field. Here, we analyze each frame to obtain the color level information, and one of every fifteen frame to obtain the motion information. In the color level analysis, we transform the RGB color space to the HSV color space for each frame in the video shot. Then we use the accumulated color histogram to separate the video shot into a series of clips. Then we analyze the clip color histograms for video indexing. In the motion level analysis, we use the spatial-relationship of pixels and the similarity of their motion vectors to cluster pixels into region, and generate a so-called motion image, which can be used to obtain the local motion histogram and global motion histogram. In the object level analysis, we search for the video objects, which are moving objects in the video sequence. We first use the difference image and the data of the motion field to find out the regions of object. Then we take a region tracing between the sub-sampled frame to find the object regions. Using these traced regions, we can calculate the centroid, and the size, and the average motion vector of the moving objects.