Patent ID: 8335350

Claim:
A method for analyzing a digital video sequence of a scene to extract background motion information and foreground motion information, the digital video sequence being captured by a digital video camera and having a time sequence of image frames, each image frame having a two-dimensional array of image pixels, comprising: using a data processor to analyze at least a portion of a plurality of image frames captured at different times to determine corresponding one-dimensional image frame representations having an associated spatial dimension; combining the one-dimensional frame representations for the plurality of image frames to form a two-dimensional spatiotemporal representation of the video sequence, one of the dimensions being a time dimension and the other dimension being the spatial dimension associated with the one-dimensional image frame representations; using a data processor to identify a set of trajectories in the two-dimensional spatiotemporal representation of the video sequence, each trajectory corresponding to a structure in the two-dimensional spatiotemporal representation of the video sequence and representing the spatial position of a feature in the video sequence as a function of time; using a data processor to analyze the set of trajectories to identify a set of foreground trajectory segments representing foreground motion information and a set of background trajectory segments representing background motion information; and storing an indication of the foreground motion information or the background motion information or both in a processor-accessible memory.