Dynamosaics: Dynamic Mosaics with Non-Chronological Time

With the limited field of view of human vision, our perception of most scenes is built over time while our eyes are scanning the scenes. In the case of static scenes this process can be modeled by panoramic mosaicing: stitching together images into a panoramic view. Can a dynamic scene, scanned by a video camera, be represented with a dynamic panoramic video?

When a video camera is scanning a dynamic scene, different regions are visible at different times. The chronological time when a region becomes visible in the input video is not part of the scene dynamics, and may be ignored. Only the “local time” during the visibility period of each region is relevant for the dynamics of the scene, and should be used for building the dynamic mosaics.

We used the space-time volume, when 2D image frames are stacked on the time axis to form a 3D volume, as a basic representation which enables to create dynamic mosaics.

Various 2D slices of the space-time volume can manipulate the chronological time and generate panoramic movies. The chronological time can even be reversed without affecting the local time. E.g., Given a video camera scanning water falls from left to right, we can generate a video scanning the falls from right to left, but in contradiction to reversal of the video sequence, the water will flow down!

Speaker Details

Shmuel Peleg received the BSc degree in mathematics from The Hebrew University of Jerusalem, Israel, in 1976 and the MSc and PhD degrees in computer science from the University of Maryland, College Park, in 1978 and 1979, respectively. He has been a faculty member at the Hebrew University of Jerusalem since 1980 and has held visiting positions at the University of Maryland, New York University, and the Sarnoff Corporation. His recent research interests include image motion analysis and image mosaicing.

Date:
Speakers:
Shmuel Peleg
Affiliation:
Hebrew University of Jerusalem