By the end of week 1, I built a Hough Transform component to detect lines from captured image by web camera (Microsoft-VX 6000).
It could detect lines corresponding to edges of shelves, under certain conditions. Now I don't have any data-sets available, such as still images and movies at a grocery store. So I tested it by using a desk in my laboratory.
This is an example of captured image with two boxes of RITZ.
And here is the result of Hough Transform. This software detects lines whose slopes are under 30 degrees to the horizontal line, so that it could detect those corresponding to edges of shelves.
The red line and the blue line are corresponding to edges of the desk. And a green circle is a "middle point" of these lines. In this case, the circle represents the location of edges well.