Abstract: Images uploaded by users of a social networking system are analyzed to determine signatures of cameras used to capture the images. A camera signature comprises features extracted from images that characterize the camera used for capturing the image, for example, faulty pixel positions in the camera and metadata available in files storing the images. Associations between users and cameras are inferred based on actions relating users with the cameras, for example, users uploading images, users being tagged in images captured with a camera, and the like. Associations between users of the social networking system related via cameras are inferred. These associations are used beneficially for the social networking system, for example, for recommending potential connections to a user, recommending events and groups to users, identifying multiple user accounts created by the same user, detecting fraudulent accounts, and determining affinity between users.

Abstract: Systems and methods for protecting the privacy of users by controlling access to the users' data. In particular, some embodiments provide for a higher-level declarative language for expressing privacy policies which can be verified using a computer-aided verification tool. The verification tool uses the expressed privacy policies along with language-level assumptions and assertions in the verification process. For example, high-level models of the privacy policies can be reduced to a simpler verification representation (e.g., a Boolean representation) based on a set of assertions. This verification representation can then be submitted to a constraint solver (e.g., Satisfiability Modulo Theories solver) for verification.

Abstract: Images uploaded by users of a social networking system are analyzed to determine signatures of cameras used to capture the images. A camera signature comprises features extracted from images that characterize the camera used for capturing the image, for example, faulty pixel positions in the camera and metadata available in files storing the images. Associations between users and cameras are inferred based on actions relating users with the cameras, for example, users uploading images, users being tagged in images captured with a camera, and the like. Associations between users of the social networking system related via cameras are inferred. These associations are used beneficially for the social networking system, for example, for recommending potential connections to a user, recommending events and groups to users, identifying multiple user accounts created by the same user, detecting fraudulent accounts, and determining affinity between users.

Abstract: Images uploaded by users of a social networking system are analyzed to determine signatures of cameras used to capture the images. A camera signature comprises features extracted from images that characterize the camera used for capturing the image, for example, faulty pixel positions in the camera and metadata available in files storing the images. Associations between users and cameras are inferred based on actions relating users with the cameras, for example, users uploading images, users being tagged in images captured with a camera, and the like. Associations between users of the social networking system related via cameras are inferred. These associations are used beneficially for the social networking system, for example, for recommending potential connections to a user, recommending events and groups to users, identifying multiple user accounts created by the same user, detecting fraudulent accounts, and determining affinity between users.

Abstract: Users of an online system are authenticated based on signatures of cameras that were used to capture images uploaded to the online system. Users of an online system upload photos taken from their cameras. The online system extracts characteristic information about the camera that captured the photos. This information includes a mapping of faulty pixels, metadata included with the photos, a naming convention, and the like. The online system stores an association between the user and the camera. This association is used for authentication of the user. For authentication, the user is asked to upload new photos taken from the camera that the user used previously. The information extracted from the newly uploaded photos is matched against stored information of cameras used previously by the user. The user is successfully authenticated if the camera used for the newly uploaded photos matches a previously stored camera.

Abstract: Images uploaded by users of a social networking system are analyzed to determine signatures of cameras used to capture the images. A camera signature comprises features extracted from images that characterize the camera used for capturing the image, for example, faulty pixel positions in the camera and metadata available in files storing the images. Associations between users and cameras are inferred based on actions relating users with the cameras, for example, users uploading images, users being tagged in images captured with a camera, and the like. Associations between users of the social networking system related via cameras are inferred. These associations are used beneficially for the social networking system, for example, for recommending potential connections to a user, recommending events and groups to users, identifying multiple user accounts created by the same user, detecting fraudulent accounts, and determining affinity between users.

Abstract: Users of an online system are authenticated based on signatures of cameras that were used to capture images uploaded to the online system. Users of an online system upload photos taken from their cameras. The online system extracts characteristic information about the camera that captured the photos. This information includes a mapping of faulty pixels, metadata included with the photos, a naming convention, and the like. The online system stores an association between the user and the camera. This association is used for authentication of the user. For authentication, the user is asked to upload new photos taken from the camera that the user used previously. The information extracted from the newly uploaded photos is matched against stored information of cameras used previously by the user. The user is successfully authenticated if the camera used for the newly uploaded photos matches a previously stored camera.

Abstract: Users of an online system are authenticated based on signatures of cameras that were used to capture images uploaded to the online system. Users of an online system upload photos taken from their cameras. The online system extracts characteristic information about the camera that captured the photos. This information includes a mapping of faulty pixels, metadata included with the photos, a naming convention, and the like. The online system stores an association between the user and the camera. This association is used for authentication of the user. For authentication, the user is asked to upload new photos taken from the camera that the user used previously. The information extracted from the newly uploaded photos is matched against stored information of cameras used previously by the user. The user is successfully authenticated if the camera used for the newly uploaded photos matches a previously stored camera.

Abstract: Users of an online system are authenticated based on signatures of cameras that were used to capture images uploaded to the online system. Users of an online system upload photos taken from their cameras. The online system extracts characteristic information about the camera that captured the photos. This information includes a mapping of faulty pixels, metadata included with the photos, a naming convention, and the like. The online system stores an association between the user and the camera. This association is used for authentication of the user. For authentication, the user is asked to upload new photos taken from the camera that the user used previously. The information extracted from the newly uploaded photos is matched against stored information of cameras used previously by the user. The user is successfully authenticated if the camera used for the newly uploaded photos matches a previously stored camera.

Abstract: Images uploaded by users of a social networking system are analyzed to determine signatures of cameras used to capture the images. A camera signature comprises features extracted from images that characterize the camera used for capturing the image, for example, faulty pixel positions in the camera and metadata available in files storing the images. Associations between users and cameras are inferred based on actions relating users with the cameras, for example, users uploading images, users being tagged in images captured with a camera, and the like. Associations between users of the social networking system related via cameras are inferred. These associations are used beneficially for the social networking system, for example, for recommending potential connections to a user, recommending events and groups to users, identifying multiple user accounts created by the same user, detecting fraudulent accounts, and determining affinity between users.