Abstract: A compact video image recording device for recording video images before and after a triggering event and which utilizes no moving parts is disclosed. The recording device includes at least one camera wherein each camera comprises a lens and a video image sensor. Each video image sensor generates an electronic signal representative of a video image impinging the respective sensor. The output of each image sensor is processed, compressed and generally employed to produce frame data which are successively stored in a successive frame locations of a semiconductor memory organized as a circular buffer memory. Upon the occurrence of a triggering event, a additional frames are stored in the buffer memory and further storage of frames then terminates. A video record is thus created of video images received both before and after the triggering event via a device which contains no moving parts and which can withstand substantial shock and vibration.

Abstract: A method compensates for drift in macroblocks of a partially decoded input bitstream. The macroblocks include intra-mode and inter-mode macroblocks, and each macroblock includes DCT coefficients, and at least one motion vector. An estimate of drift is measured in the partially decoded input bitstream. The estimated drift is translated into an intra refresh rate. The modes of inter-mode macroblock are mapped to intra-mode macroblock according to the refresh rate. The DCT coefficients and the motion vector for each changed macroblock are modified in accordance with the mapping for each changed macroblock.

Abstract: A multi-path interference canceller cancels interference in a signal received by a receiver in a wideband CDMA communications system. A first stage of the canceller has as input the received signal. Each next stage has as input a delayed version of the input of the previous stage. Each stage includes a first channel estimation and interference generation unit for estimating interference in high-speed signal components of the input signal, and a second channel estimation and interference generation unit for estimating interference in low-speed signal components of the input signal. The interference estimated in the previous stage by the first and second channel estimation and interference generation units is then removed from the input signal of the next stage.

Abstract: A method learns a binary classifier for classifying samples into a first class and a second class. First, a set of training samples is acquired. Each training sample is labeled as either belonging to the first class or to the second class. Pairs of dyadic samples are connected by projection vectors such that a first sample of each dyadic pair belonging to the first class and a second sample of each dyadic pair belonging to the second class. A set of hyperplanes are formed so that the hyperplanes have a surface normal to the projection vectors. One hyperplane from the set of hyperplanes is selected that minimizes a weighted classification error. The set of training samples is then weighted according to a classification by the selected hyperplane. The selected hyperplanes are combined into a binary classifier, and the selecting, weighting, and combining are repeated a predetermined number of iterations to obtain a final classifier for classifying test samples into the first and second classes.

Abstract: An optical communications transceiver includes an LED coupled in series with a resistor. A microprocessor has one I/O pin connected to the LED. In a first mode or transmit mode, the LED is periodically driving in forward bias to emit light to transmit data. In a second or receive mode, the LED is periodically not driven in reverse bias, e.g., reverse bias or zero bias. Then, the LED is allowed to change charge of the capacitance of the LED's junction using a photo-current. The change in charge is measured using a timer. When the change in charge exceeds a predetermined threshold, input light is sensed. Thus, the LED can be used to receive data in the second mode.

Abstract: A computer implemented method animates a 3D physical object by first acquiring a 3D graphics model of the object. The model is edited with graphics authoring tools to reflect a desired appearance of the object. The edited model is rendered as an image considering a user location and a location of a virtual light. Then, intensity values of the image are corrected according to an orientation of a surface of the object and a radiance at the surface. The 3D physical object can finally be illuminated with the corrected image to give the 3D physical object the desired appearance under the virtual light when viewed from the user location.

Abstract: A system and method reduces noise in a time series signal. A primary signal including stationary and non-stationary noise is modeled by a dynamic system having a continuum of states. A secondary signal including time series data is added to the primary signal to form a combined signal. The generic noise in the combined signal is estimated from samples of the combined signal using the dynamic system modeling the generic noise. Then, the estimated generic noise is removed from the combined signal to recover time series data.

Abstract: A method extracts speech recognition features from a speech signal coded as a bitstream. First, the bitstream is decoded to recover linear predictive coding filter parameters, and a residual signal. Then, the linear predictive coding filter parameters and the residual signal are discriminatively combined into speech recognition features.

Abstract: A method classifies an object in a scene as either an ambulatory person or a wheelchair user. Images of the scene are acquired with a set of stereo cameras. Moving objects in the scene are segmented from the background using detected edges. A 3D reconstruction of the object is generated from the edges, and tests are performed on height and 3D shape of the 3D reconstruction to classify the object as the ambulatory person or the wheelchair user.

Abstract: A method generates a distance field for a region of a shape descriptor representing an object. The distance field includes a set of cells for which cell types are defined. A configuration of a set of cells for the region is generated. Each cell of the configuration includes a cell type and a method for reconstructing the distance field within the cell. The configuration of the set of cells is modified until an optimal configuration is reached. The modification is based on the shape descriptor, the region, and the set of cell types. The optimal configuration of the set of cells is stored in a memory to generate the distance field for the region. Another method generates a two-dimensional distance field within a cell associated with a two-dimensional object. A set of boundary descriptors for the two-dimensional object is determined and partitioned into a set of segments. The segments are delimited by a set of features of the boundary descriptors.

Abstract: Timing in a receiver is synchronized to an orthogonal frequency division multiplex (OFDM) signal transmitted over a channel. The OFDM signal includes multiple training symbols, including long and short training symbols. The first half of the training symbols are correlated with the second half to determine a coarse index which is used to adjust the unsynchronized OFDM. In the coursely adjusted OFDM signal, the first training symbol is then correlated with the last traininig symbol to determine a fine index to adjust the coarsely adjusted OFDM signal so that the receiver is synchronized with the transmitted OFDM signal.

Abstract: A method and system that increases transmit diversity gain in a wireless communication system. The system includes a transmitter with 2N transmit antennas, where N is greater than one, and a receiver with one or more receive antenna. The transmitter includes N stages connected serially to each other. The first stage is a symbol level space-time transmit diversity encoder. Each of the next N?1 stages is a block level space-time transmit diversity encoder, for a total of N stages. The last stage is connected to the 2N antennas. The transmitter generates pairs of symbols in a form X1 and X2, The pairs of symbols are encoded by the first stage to produce a 21×21 output matrix C. Then, in each next block level stage n, the 2n?1×2n?1 output matrix of a previous stage is encoded to a 2n×2n output matrix, until a final output matrix has 2N rows of transmit symbols.

Abstract: A camera includes a set of sensing elements. Each sensing element is arranged at an image plane in an energy field to measure a magnitude and sign of a local gradient of the energy field. Each sensing element includes at least two energy intensity sensors. Each energy sensor measures a local intensity of the energy field. Logarithms of the intensities are subtracted from each other to obtain the magnitude and sign of the gradients. A Poisson equation is solved using the gradients to obtain an output image of the energy field.

Abstract: A method converts range data of an object to a model of the object by first generating an adaptively sampled distance field from the range data. The adaptively sampled distance field is then edited to produce the model. The range data can include a plurality of range images that are converted to range meshes in a single coordinate system, and an adaptively sampled distance field is generated for each of the range meshes.

Abstract: A system and method reduce power consumption in a multi-hop wireless communications network. A signal is received from a source node in an intermediate node. The signal includes a request to relay a message to a destination node. The request includes information on power requirements to relay the message either in a relay mode or a regeneration mode. If the available power at the intermediate node exceeds the power requirements, then the request is accepted. Either the relay mode or the regeneration mode is selected, based on criteria for retransmitting the message, and the message is then relayed to the destination node using the selected mode.

Abstract: A method and apparatus determine an antialiased intensity of a component of a pixel from a two-dimensional distance field representing an object. A set of sample points in the two-dimensional distance field is associated with the component of the pixel. A distance is determined from the two-dimensional distance field and the set of sample points and then mapped to the antialiased intensity of the component of the pixel.

Abstract: A method generates a two-dimensional distance field within a cell associated with a corner of a two-dimensional object. A set of boundary descriptors for the two-dimensional object is determined. A corner point in the cell is identified from the set of boundary descriptors. The corner point represents the corner of the object. The corner point partitions the set of boundary descriptors into two subsets. The cell is partitioned into two regions where one region is closest to the corner point and the other region is closest to the set of boundary descriptors. Two lines passing through the corner point are determined such that each line corresponds to one of the two subsets of boundary descriptors. These lines delimit the two regions. A set of values and a method using the two regions are specified for reconstructing the distance field within the cell.

Abstract: A method converts a two-dimensional object to a two-dimensional distance field. The object is represented as a set of boundary descriptors and a fill rule. The set of boundary descriptors is preprocessed and a spatial hierarchy is constructed from the preprocessed set of boundary descriptors. A cache of intersections is initialized. The spatial hierarchy is queried at a set of locations to determine a set of distances at the locations. The query invokes a distance function at each location to determine an unsigned distance. A sign of the unsigned distance is determined from the cache of intersections, the location, and the fill rule. The set of distances is used to construct the two-dimensional distance field.

Abstract: A method detects edges of an object in a scene by first acquiring a static image of the scene when the scene is static, and a live image of the scene including the object. A reference image is constructed from the static image. Then, image gradients of the reference image are compared with image gradients of the live image to identify edges of the object in the live image.

Abstract: A method recognizes an object in an image. Gallery images include identified objects, and a probe image includes an unidentified object. The probe image is paired with each gallery image to generate pairs of images. First filters are applied to the probe image of each pair to obtain a first feature value for each application of each filter. Second filters are applied to the each gallery image of each pair to obtain a second feature value for each application of each filter. The feature values are summed for each application of each filter, and for each application, a score is set to an acceptance weight if the sum is greater than a predetermined threshold, and otherwise setting the score to a rejection weight. The scores are summed for all of the application, and the probe image is identified with any gallery image when the score is greater than zero.