Abstract: Systems and methods for reducing signal noise in an x-ray emitter/detector system are disclosed. A common clock is connected to at least two subsystems of the x-ray emitter/detector system to enable a plurality of noise sources associated with the at least two subsystems within the x-ray emitter/detector system to be correlated with the common clock. At least one adaptive filter having a plurality of taps is configured to receive a desired signal and a correlated noise estimate signal and output an error signal. An update algorithm is used to update a value of the plurality of taps to minimize the error signal output to thereby substantially remove at least one of the plurality of noise sources at each of the at last one variable filters in the x-ray emitter/detector system to provide a more accurate display of the output of the x-ray emitter/detector system.

Abstract: A peripheral module capable of interaction with a host system comprises a digital signal processor (DSP), a cache controller, and minimal or no resident memory for initial storage of instructions and data. The peripheral module utilizes the memory resources (e.g., ROM and RAM) of a host system. The cache controller interfaces to the DSP and provides an instruction and data stream, upon request, from a resident cache. A bus interface unit arbitrates access to the host system via a host bus for access to host system resources by the cache controller for extracting DSP information (e.g., instructions and data) from the host system for utilization by the DSP within the peripheral module. The cache controller and cache thereby provide the instruction and data stream as required by the DSP for digital signal processing applications and relieve the need for resident storage within the peripheral module.

Abstract: The compression method utilizes a combination of both lossy and lossless compression to achieve significant compression while retaining very high subjective quality of the reconstructed or decompressed signal. Methods and apparatus for compression and decompression of digital audio data are provided. In one preferred embodiment, the compression method or apparatus has a bit rate control feedback loop particularly well suited to matching the output bit rate of the data compressor to the bandwidth capacity of a communication channel. Embodiments trade-off various error sources in order to keep perceptible distortion levels to a minimum for a fixed bit rate. Preferred embodiments also utilize a unique combination of run length and Huffman encoding methods in order to take advantage of both local and global statistics.