A heritage or historic place is usually spread over a large
geographic area with interesting structures at dierent locations
within the site. There exists a specied route to be
taken for some sites to easily tour the place.
We enable a tourist to look-up his current position on the
map and guide himself on the prescribed route at a heritage
site. On the mobile device, we store a map of the place,
with the important structures, buildings and other objects
and regions marked out clearly. A tourist can click a few
images from his current location on the marked route and
query our application for his position. The map also displays
the other important structures or scenes near by and directs
the tourist on the prescribed route for exploring the site.
We call this functionality as Pseudo-GPS Navigation as it
works similar to GPS systems, but only using images.
We demonstrate this application at Golkonda Fort(See
Figure 4), where there is a prescribed route (approximately
2km long) to tour the site. We collected training images
from 43 locations, separated by a few meters on the route.
Each such location is a nodal point, which helps in identifying
a tourist's position, discretely on the map. Ideally, each
nodal point spans approximately 4-5 meters and is separated
from its next nodal point by 10-11 meters. As a tourist tries
to nd his location on the route, he clicks 5-10 images of
intuitively distinct structures visible from his current location.
Our application performs BoW-based image retrieval
for each of these query images and scores the nodal points
according to the images retrieved. The location corresponding
to the nodal point with highest score is highlighted as
the current position of the tourist on the map. Here, the
query images are annotated by a position index on the map.