Abstract: Methods and computer-readable media for propagating content category information to images stored in a database are described. A seed image that is associated with a known content category is received. A content-based image retrieval is conducted using the seed image as a search query image. A number of search result images are identified. The content category is propagated to the search result images. Metadata associated with the search result images is aggregated and analyzed to identify domains that should also be associated with the content category. Additional images that are associated with the domain are identified and the content category propagated thereto. The process is iterated using the additional images as search query images for the content-based image retrieval.

Abstract: Systems, methods, and computer media for enhancing user search query results are provided. Upon receiving a user search query, relevant images are identified. Duplicate image information for the relevant images is accessed in an index. The index includes information extracted from individual images or duplicates and information aggregated according to groups comprised of images and duplicates of the images. The images identified as relevant to the user query are ranked based at least in part on the information accessed in the index.

Abstract: Image descriptor identifiers are used for content-based search. A plurality of descriptors is determined for an image. The descriptors represent the content of the image at respective interest points identified in the image. The descriptors are mapped to respective descriptor identifiers. The image can thus be represented as a set of descriptor identifiers. A search is performed on an index using the descriptor identifiers as search elements. A method for efficiently searching the inverted index is also provided. Candidate images that include at least a predetermined number of descriptor identifiers that match those of the image are identified. The candidate images are ranked and at least a portion thereof are presented as content-based search results.

Abstract: An efficient manner of performing an M-out-of-N partial matching search of indexed documents (e.g., web pages) is provided herein. More particularly, indexed words are arranged into a global location space (GLS), providing for respective occurrences of words in indexed documents being searched to have continuous locations on a one-dimensional GLS. Documents within the GLS are separated by end of document word marking boundaries between consecutive documents. The query words are then separated into an active set, comprising the left-most query words, and a non-active set. A partial matching operator transverses the GLS, applying active geometric constraints, in a sequential manner, to words in the active set. This causes shifting of the active set along the GLS to comprise M left-most query words. If a document satisfies constraints associated with M words in an active set, the document comprises at least M-out-of-N words.

Abstract: Methods are disclosed for finding images from a large corpus of images that at least partially match a query image. The present method makes use of feature detectors to bundle features into local groups or bundles. These bundled features are repeatable and much more discriminative than an individual SIFT feature. Equally importantly, the bundled features provide a flexible representation that allows simple and robust geometric constraints to be efficiently enforced when querying the index.

Abstract: Computer implemented methods are disclosed for detecting bot-user groups that send spam email over a web-based email service. Embodiments of the present system employ a two-prong approach to detecting bot-user groups. The first prong employs a historical-based approach for detecting anomalous changes in user account information, such as aggressive bot-user signups. The second prong of the present system entails constructing a large user-user relationship graph, which identifies bot-user sub-graphs through finding tightly connected subgraph components.

Abstract: The present invention uses invisible junctions which are a set of local features unique to every page of the electronic document to match the captured image to a part of an electronic document. The present invention includes: an image capture device, a feature extraction and recognition system and database. When an electronic document is printed, the feature extraction and recognition system captures an image of the document page. The features in the captured image are then extracted, indexed and stored in the database. Given a query image, usually a small patch of some document page captured by a low resolution image capture device, the features in the query image are extracted and compared against those stored in the database to identify the query image. The present invention advantageously uses geometric estimation to reduce the query results to a single one or a few candidate matches. In one embodiment, the two separate geometric estimations are used to rank and verify matching candidates.

Abstract: The present invention uses invisible junctions which are a set of local features unique to every page of the electronic document to match the captured image to a part of an electronic document. The present invention includes: an image capture device, a feature extraction and recognition system and database. When an electronic document is printed, the feature extraction and recognition system captures an image of the document page. The features in the captured image are then extracted, indexed and stored in the database. Given a query image, usually a small patch of some document page captured by a low resolution image capture device, the features in the query image are extracted and compared against those stored in the database to identify the query image. The present invention also includes methods for recognizing and tracking the viewing region and look at point corresponding to the input query image.

Abstract: The present invention uses invisible junctions which are a set of local features unique to every page of the electronic document to match the captured image to a part of an electronic document. The present invention includes: an image capture device, a feature extraction and recognition system and database. When an electronic document is printed, the feature extraction and recognition system captures an image of the document page. The features in the captured image are then extracted, indexed and stored in the database. Given a query image, the features in the query image are extracted and compared against those stored in the database to identify the query image. The feature extraction and recognition system of the present invention is integrated into a multifunction peripheral. This allows the feature extraction and recognition system to be used in conjunction with other modules to provide security and annotation applications.

Abstract: The present invention uses invisible junctions which are a set of local features unique to every page of the electronic document to match the captured image to a part of an electronic document. The present invention includes: an image capture device, a feature extraction and recognition system and database. When an electronic document is printed, the feature extraction and recognition system captures an image of the document page. The features in the captured image are then extracted, indexed and stored in the database. Given a query image, usually a small patch of some document page captured by a low resolution image capture device, the features in the query image are extracted and compared against those stored in the database to identify the query image. The present invention also includes methods for feature extraction, feature indexing, feature retrieval and geometric estimation.

Abstract: The present invention uses invisible junctions which are a set of local features unique to every page of the electronic document to match the captured image to a part of an electronic document. The present invention includes: an image capture device, a feature extraction and recognition system and database. When an electronic document is printed, the feature extraction and recognition system captures an image of the document page. The features in the captured image are then extracted, indexed and stored in the database. Given a query image, usually a small patch of some document page captured by a low resolution image capture device, the features in the query image are extracted and compared against those stored in the database to identify the query image. The present invention also includes methods for recognizing and tracking the viewing region and look at point corresponding to the input query image.

Abstract: A system and a method are disclosed for generating video. Object information is received. A path of motion of the object relative to a reference point is generated. A series of images and ground for a reference frame are generated from the ground truth and the generated path. A system and a method are disclosed for generating an image. Object information is received. Image data and ground truth may be generated using position, the image description, the camera characteristics, and image distortion parameters. A positional relationship between the document and a reference point is determined. An image of the document and ground truth are generated from the object information and the positional relationship and in response to user specified environment of the document.

Abstract: A method and apparatus for recovering a three-dimensional (3D) scene from two-dimensional (2D) images. A sequence of images is divided into a number of smaller segments and a 3D reconstruction is performed on each segment individually. All the reconstructed segments are then combined together through an efficient bundle adjustment to complete the 3D reconstruction. Segmenting may be achieved by dividing the segments based on the number of feature points that are in each frame. The number of frames per segment is reduced by creating virtual key frames. The virtual key frames encode the 3D structure for each segment, but are only a small subset of the original frames in the segment. A final bundle adjustment is performed on the virtual key frames, rather than all of the original frames. Thus, the final bundle adjustment is two orders of magnitude faster than a conventional bundle adjustment.

Abstract: An image based system and process for rendering novel views of a real or synthesized 3D scene based on a series of concentric mosaics depicting the scene. In one embodiment, each concentric mosaic represents a collection of consecutive slit images of the surrounding 3D scene taken from a different viewpoint tangent to a circle on a plane within the scene. Novel views from viewpoints within circular regions of the aforementioned circle plane defined by the concentric mosaics are rendered using these concentric mosaics. Specifically, a slit image can be identified by a ray originating at its viewpoint on the circle plane and extending toward the longitudinal midline of the slit image. Each of the rays associated with the slit images needed to construct a novel view will either coincide with one of the rays associated with a previously captured slit image, or it will pass between two of the concentric circles on the circle plane.