The phrase “window shopping” perhaps brings to mind leisurely strolls on Main Street, where elegantly decorated shop displays encourage dreaming of – and carefully planning for – future purchases. You might even think of Audrey Hepburn as Holly Golightly, wandering by the famous jewelry store windows in the 1961 romantic comedy Breakfast at Tiffany’s. Artful but merely passive window displays – clothing ensembles, sports equipment, cookware, household goods, shoes and boots, floral arrangements and all other possible merchandise – are still, of course, found at malls, outlets and shopping venues everywhere. But technology may be about to transform the traditional and perhaps shopworn window viewing experience into an interactive encounter where, with simple gestures outside the window, a shopper can view goods in detail and even make on-the-spot purchases. When placed within a window display, a new 3-D camera system from the Fraunhofer Institute for Telecommunications, Heinrich Hertz Institute in Berlin picks up hand and facial gestures from window gazers. Four cameras continually record the 3-D positions of the hands, faces and eyes of passersby: Two of the cameras record the face and eyes, and the other two record the motion of the hands. Image processing recognizes the gestures and changes them into corresponding inputs. If a pair of skis catches a shopper’s eye, she can point to them, and their image will appear on a screen. With gestures alone, she can zoom in and rotate the image for a closer look, and check on product details – and then purchase the skis, if she so desires, even if the store is closed. Above, A 3-D camera system enables these window-shoppers to call up the details on a scarf and to purchase it window-side, if they wish. Courtesy of Fraunhofer HHI. Still in prototype, the interactive shop window unit is compatible with many types of monitors, including plasma, LED, LCD, projection and reprojection screens. Shop owners will be able to link the system to their content management or merchandise information software to provide product information. The interactive system may also provide shop owners with data on products and information that have generated particular interest from the window-shopping audience – but it won’t collect personal data on shoppers, the developers said. Also, the unit will customize greetings to help create a stronger bond with the shopper. As the 21st century progresses, you might want to bring along your wallet when you go window-shopping. You never know what might call to you.