Dynamic Collage

Browsing large photo collection in an efficient and pleasing way is a great challenge. Existing technique for browsing large photo collections can be classified into two different approaches on the arrangement of images: spatial arrangement methods and temporal arrangement methods. Spatial arrangement methods aim to create a single 2D representation for a photo collection utilizing the screen space. Traditional mosaic method lines up photos in a simple grid in a non-overlapping manner, later works use better algorithm to determine a good layout and placement of images, but all these works don't allow photo overlapping. Recent technique named collage allows unimportant area of a photo to be covered by other photos, so it improves the utilization of screen space. Temporal arrangement methods mostly display photo collection in a sequential manner with one image displayed at a time. Some new technique allow image mosaics to be sequentially displayed, it consider arrangement and temporal arrangement simultaneously but lose the temporal continuity of the presentation.Dynamic collage proposed in this paper is an efficient technique for browsing large photo collection that combines spatial arrangement method and temporal arrangement method, achieving spatial compactness and temporal continuity simultaneously. Unlike previous techniques that focus on generating a static two-dimensional arrangement of photos (such as thumbnails and collage), dynamic collage explicitly considers temporal transition and dynamically create a time-varying collage from the large photo collection. In order to retain the temporal continuity, dynamic collage only updates a little few photos instead of updating all photos in the screen like what previous temporal arrangement methods do, using an efficient incremental optimization algorithm based on locally adjustment to update the placement of all photos (the center position, the angle, and the layer of all photos) aiming to maximize the visual information so that temporal continuity of the browsing process is preserved. Compared to previous algorithms for browsing photo collection, dynamic collage dramatically increases the size of the photo collections to be browsed, enriches users' visual experience, best utilizes the screen space and user time, and achieves a nice experience for browsing photo collection.