Abstract: Unauthorized entry into controlled access areas using tailgating or reverse entry methods is detected using machine vision methods. Camera images of the controlled area are processed to identify and track objects in the controlled area. In a preferred embodiment, this processing includes 3D surface analysis to distinguish and classify objects in the field of view. Feature extraction, color analysis, and pattern recognition may also be used for identification and tracking of objects. Integration with security monitoring and control systems provides notification when a tailgating or reverse entry event has occurred. More reliable operation in practical circumstances is thus obtained, such as when multiple people are using an entrance or exit under variable light and shadow conditions. Electronic access control systems may further be combined with the machine vision methods of the invention to more effectively prevent tailgating or reverse entry.

Abstract: Unauthorized entry into controlled access areas using tailgating or reverse entry methods is detected using machine vision methods. Camera images of the controlled area are processed to identify and track objects in the controlled area. In a preferred embodiment, this processing includes 3D surface analysis to distinguish and classify objects in the field of view. Feature extraction, color analysis, and pattern recognition may also be used for identification and tracking of objects. Integration with security monitoring and control systems provides notification when a tailgating or reverse entry event has occurred. More reliable operation in practical circumstances is thus obtained, such as when multiple people are using an entrance or exit under variable light and shadow conditions. Electronic access control systems may further be combined with the machine vision methods of the invention to more effectively prevent tailgating or reverse entry.

Abstract: Various methods, systems, and apparatus for implementing aspects of a digital mapping system are disclosed. One such method includes sending a location request from a client-side computing device to a map tile server, receiving a set of map tiles in response to the location request, assembling said received map tiles into a tile grid, aligning the tile grid relative to a clipping shape, and displaying the result as a map image. One apparatus according to aspects of the present invention includes means for sending a location request from a client-side computing device to a map tile server, means for receiving a set of map tiles in response to the location request, means for assembling said received map tiles into a tile grid, means for aligning the tile grid relative to a clipping shape, and means for displaying the result as a map image.

Abstract: Various methods, systems, and apparatus for implementing aspects of a digital mapping system are disclosed. One such method includes sending a location request from a client-side computing device to a map tile server, receiving a set of map tiles in response to the location request, assembling said received map tiles into a tile grid, aligning the tile grid relative to a clipping shape, and displaying the result as a map image. One apparatus according to aspects of the present invention includes means for sending a location request from a client-side computing device to a map tile server, means for receiving a set of map tiles in response to the location request, means for assembling said received map tiles into a tile grid, means for aligning the tile grid relative to a clipping shape, and means for displaying the result as a map image.

Abstract: Unauthorized entry into controlled access areas using tailgating or reverse entry methods is detected using machine vision methods. Camera images of the controlled area are processed to identify and track objects in the controlled area. In a preferred embodiment, this processing includes 3D surface analysis to distinguish and classify objects in the field of view. Feature extraction, color analysis, and pattern recognition may also be used for identification and tracking of objects. Integration with security monitoring and control systems provides notification when a tailgating or reverse entry event has occurred. More reliable operation in practical circumstances is thus obtained, such as when multiple people are using an entrance or exit under variable light and shadow conditions. Electronic access control systems may further be combined with the machine vision methods of the invention to more effectively prevent tailgating or reverse entry.