Abstract:
The present invention extends to methods, systems, and computer program products for deriving document similarity indices. Embodiments of the invention include scalable and efficient mechanisms for deriving and updating a document similarity index for a plurality of documents. The number of maintained similarities can be controlled to conserve CPU and storage resources.
Abstract:
A method includes receiving a concept hierarchy at a computing device. The concept hierarchy identifies concepts associated with a document corpus. An interface based on the concept hierarchy is generated. The interface is operable to navigate, search, and modify the concept hierarchy. The method includes transmitting the interface for display to a display device.
Abstract:
A decoder processes a first bitstream element (e.g., a pull-down flag) in a first syntax layer (e.g., sequence layer or entry point layer) above frame layer in a bitstream for a video sequence, the bitstream comprising encoded source video having a source type (e.g., progressive or interlace). The decoder processes frame data in a second syntax layer (e.g., frame layer) of the bitstream for a frame (such as an interlaced frame or progressive frame, depending on source type, or a skipped frame) in the video sequence. The first bitstream element indicates whether a repeat-picture element (e.g., a repeat-frame element or a repeat field-element) is present or absent in the frame data in the second syntax layer.
Abstract:
Techniques and tools for signaling reference frame distances are described. For example, a video encoder signals a code for a reference frame distance for a current field-coded interlaced video frame. The code indicates a count of frames (e.g., bi-directionally predicted frames) between the current frame and a preceding reference frame. The code may be a variable length code signaled in the frame header for the current frame. The encoder may selectively signal the use of a default value for reference frame distances rather than signal a reference frame distance per frame. A video decoder performs corresponding parsing and decoding.
Abstract:
Biasing of language model customization due to repetitious data is substantially reduced by introducing novelty screening to data harvesting process. Novelty detection based filtering is added to ensure that an adaptation system gives more weight to representative adaptation data that is not repetitious. The value of the adaptation data is preserved and the process prevented from being polluted when the same data is seen multiple times, such as the original posting in an email thread, various versions of the same document, and the like. The screening technique may be built on top of existing data harvesting mechanisms as already seen data is used to determine the novelty of a particular portion of the data. A window into the new data, fixed or variable size, is compared against the already collected data to determine the likelihood that the data is novel.
Abstract:
An indexing system uses a graph-like data structure that clusters features indexes together. The minimum atomic value in the data structure is represented as a leaf node which is either a single feature index or a sequence of two or more feature indexes when a minimum sequence length is imposed. Root nodes are formed as clustered collections of leaf nodes and/or other root nodes. Context nodes are formed from root nodes that are associated with content that is being indexed. Links between a root node and other nodes each include a sequence order value that is used to maintain the sequencing order for feature indexes relative to the root node. The collection of nodes forms a graph-like data structure, where each context node is indexed according to the sequenced pattern of feature indexes. Clusters can be split, merged, and promoted to increase the efficiency in searching the data structure.
Abstract:
An encoder/decoder uses intra-coded B-fields [“BI-fields”]. For example, rather than encoding many of the macroblocks in a field as intra macroblocks at a scene change, an encoder can choose to encode the entire field as intra. Encoding an entire field as a BI-field allows increased coding efficiency through reduced coding overhead at macroblock level, and without intra-frame dependency, the BI-field can still be dropped if appropriate in low-bitrate applications.
Abstract:
Techniques and tools for coding/decoding of video images, and in particular, B-frames, are described. In one aspect, a video encoder/decoder determines a fraction for a current image in a sequence. The fraction represents an estimated temporal distance position for the current image relative to an interval between a reference images for the current image. The video encoder/decoder processes the fraction along with a motion vector for a first reference image, resulting in a representation of motion (e.g., constant or variable velocity motion) in the current image. Other aspects are also described, including intra B-frames, forward and backward buffers for motion vector prediction, bitplane encoding of direct mode prediction information, multiple motion vector resolutions/interpolation filters for B-frames, proactive dropping of B-frames, and signaling of dropped predicted frames.
Abstract:
An encoder sends binary information indicating whether a prediction mode is forward or not-forward for one or more macroblocks in an interlaced B-field. For example, the encoder sends forward/not-forward decision information at B-field level in a compressed bitplane. Sending forward/not-forward prediction mode decision information in a compressed bitplane at B-field level can reduce coding overhead for prediction mode coding. A decoder performs corresponding decoding.
Abstract:
Techniques and tools for encoding and decoding motion vector information for video images are described. For example, a video encoder yields an extended motion vector code by jointly coding, for a set of pixels, a switch code, motion vector information, and a terminal symbol indicating whether subsequent data is encoded for the set of pixels. In another aspect, an encoder/decoder selects motion vector predictors for macroblocks. In another aspect, a video encoder/decoder uses hybrid motion vector prediction. In another aspect, a video encoder/decoder signals a motion vector mode for a predicted image. In another aspect, a video decoder decodes a set of pixels by receiving an extended motion vector code, which reflects joint encoding of motion information together with intra/inter-coding information and a terminal symbol. The decoder determines whether subsequent data exists for the set of pixels based on e.g., the terminal symbol.