Users of Google Street View and Bing Maps Streetside will be familiar with the stop-start effect as they navigate along a street. This is because as the user moves along the street the viewpoint jumps from one discreet 360-degree panorama, or ‘bubble’, to the next . A new street-level imaging system developed by Microsoft called Street Slide allows users to smoothly navigate along a street by creating a seamless transition between bubbles using multiperspective strip panoramas that provide an overview of the street.
The multiperspective panoramas are constructed by aligning and overlaying perspective projections of the bubble images, which are then rendered dynamically as the user slides sideways along the street. These panoramas can simulate either a perspective view (what Microsoft calls “as-perspective-as-possible”), which attempts to create the view one would get from a distance, or hyper-perspective view, which widens the field of view of the center of the panorama to better match a person’s mental model of the streetside. Microsoft calls sliding sideways in these panorama views a “street slide.”
Simulating a psudo-perspective view of the streetside in this way enhances the sense of immersion and makes it easier for user’s to find what they are looking for. Since this wider view also leaves empty space at the top and bottom of the screen there is room to include navigation and informational aids in the form of shop logos, street numbers and a mini-map. The unused space could also be used to display advertising or even social information, such as the location of friends, when connected to a social network.
Once a user locates a point of interest in the wide view they can click on a building and zoom into the relevant bubble for a closer view. Clicking on an icon will also let the user switch to a view of the opposite side of the street or turn left or right at an intersection. Doing this zooms the view into the bubble, making use of its 360-degree view to turn, before zooming back out, all in one continuous motion. Anyone who has lost their bearings making a turn using Google Street View or Bing Maps Streetside will immediately recognize the advantages of such a system.
When developing the system, the team found that more people are using mapping applications on mobile devices than on fixed platforms. For this reason they have already made a version of Street Slide that is compatible with the iPhone, which would be extremely useful for users trying to find their way around a strange city.
The team has already processed about 2,400 panoramas covering about four kilometers (2.5-miles) on six streets with eight intersections. So far the annotations such as street names and numbers and store names have been entered manually. However, they are currently integrating the viewer into a larger database containing millions of bubbles or street level imagery and, as the system scales up, the annotations will be drawn directly from a geographic database.
Be sure to check out the video below to see the Street Slide system in action because it’s pretty impressive.