Abstract: Methods and systems to compress and decompress sequences of images, such as video frames, including compression techniques to estimate pixel values, to determine differences between the estimated pixel values and actual pixel values, to arithmetically encode a corresponding sequence of difference values or symbols as a code value, and to output the code value and associated reference information in a data stream. Decompression techniques include techniques to read the code value and associated reference information from the data stream, to arithmetically decode the symbols from the code value, and to reconstruct the sequence of video frames from the decoded symbols and the associated reference information. Also disclosed are techniques to reduce or preclude overflow of registers or buffers used to hold code range values, and to order tables of code range values to improve efficiency of table look-up operations.

Abstract: Methods and systems to detect changes in a region of space relative to baseline measurements, including to process data to detect potential objects, or contacts against a natural background environment, to characterize and geo-register the contacts, to compare and correlate the contacts with a database of known objects, and to report uncorrelated contacts as new objects in the space. Features disclosed herein may be implemented to process image data from a line-by-line image-generation system including, for example, side-looking sonar. Methods and system may be implemented with respect to multi-frequency band sonar data.

Abstract: Methods and systems to compress and decompress sequences of images, such as video frames, including compression techniques to estimate pixel values, to determine differences between the estimated pixel values and actual pixel values, to arithmetically encode a corresponding sequence of difference values or symbols as a code value, and to output the code value and associated reference information in a data stream. Decompression techniques include techniques to read the code value and associated reference information from the data stream, to arithmetically decode the symbols from the code value, and to reconstruct the sequence of video frames from the decoded symbols and the associated reference information. Also disclosed are techniques to reduce or preclude overflow of registers or buffers used to hold code range values, and to order tables of code range values to improve efficiency of table look-up operations.

Abstract: Methods and systems to detect changes in a region of space relative to baseline measurements, including to process data to detect potential objects, or contacts against a natural background environment, to characterize and geo-register the contacts, to compare and correlate the contacts with a database of known objects, and to report uncorrelated contacts as new objects in the space. Features disclosed herein may be implemented to process image data from a line-by-line image-generation system including, for example, side-looking sonar. Methods and system may be implemented with respect to multi-frequency band sonar data.

Abstract: A constrained data-adaptive signal rejector suppresses signals received through the side lobes of a sensor array while preserving signals received through the main lobes. A main beam is formed in a typical signal processing architecture. A subset of the original independent sensor signals are paired into auxiliary channels using a weighting scheme that results in a beam pattern having a null in the direction of the beam mainlobe. The auxiliary channels are then used in a traditional multiple sidelobe cancellation architecture to reject unwanted signals.

Abstract: A constrained data-adaptive signal rejector suppresses signals received through the side lobes of a sensor array while preserving signals received through the main lobes. A main beam is formed in a typical signal processing architecture. A subset of the original independent sensor signals are paired into auxiliary channels using a weighting scheme that results in a beam pattern having a null in the direction of the beam mainlobe. The auxiliary channels are then used in a traditional multiple sidelobe cancellation architecture to reject unwanted signals.