USA As Represented by Secretary of the Navy

Other

David L Buck

Brian T Williams

Roger E Hall

Elan Sharghi

Lawrence Hoff

Ronald L Bruck

A method may include the steps of segmenting an image into a plurality of tiles, calculating an upper clip limit and a lower clip limit for each tile of the plurality of tiles based upon a user input standard deviation, generating a lookup table for each tile of the plurality of tiles by linearly mapping the pixels of the image based upon the calculated upper clip limit and lower clip limit, processing each tile of the plurality of tiles based upon the generated lookup table, and generating a processed image by combining each of the processed tiles. The method may include the steps of scaling the image between zero and one and/or scaling the image based upon the display type. The method may be stored on a computer readable medium and may be used in an image processing system having memory, a processor, and a display.

Adaptive linear contrast method for enhancement of low-visibility imagery

A method includes the steps of selecting an image filtering technique, receiving an image from an image source, processing the received image to provide a processed image, and displaying the processed image to a user. Processing the received image includes the steps of adjusting the received image to provide an adjusted image, filtering the adjusted image according to the selected image filtering technique to provide a filtered image, and adjusting the filtered image. The image filtering technique may be selected from histogram equalization, band-pass filtering, adaptive enhancement filtering, or other techniques. The method may be used in an image processing system having memory, a processor, and a display.

System and method for enhancing low-visibility imagery

A software controlled crystal oscillator employing a method for digitally controlling a reference frequency of an oscillator, the method includes the steps of: locking a first signal produced by a first tunable software oscillator on to a first resonant frequency of a temperature sensing resonator; locking a second signal produced by a second tunable software oscillator on to a second resonant frequency of the temperature sensing resonator; estimating a temperature of the temperature sensing resonator using the first signal and the second signal; estimating the first resonant frequency and the second resonant frequency based upon the temperature; and adjusting the first signal to approximate the estimated first resonant frequency. An additional step includes controlling the reference frequency of the oscillator based upon the first signal such that the reference frequency is compensated for temperature.

Software controlled crystal oscillator

A communication interface circuit for interfacing a processor with a plurty of application devices is provided. Circuitry monitors input/output (I/O) addresses passed on the processor's data transfer bus and provides a first enable signal when an I/O addresses indicates that operation of the communication interface circuit has been requested by the processor. Control logic, in response to the first enable signal, is then given access to configuration data passed on the data transfer bus associated with the one I/O address. The control logic interprets the data and produces a second enable signal in accordance therewith. A plurality of programmable controllers, in response to the second enable signal, are initialized by the configuration data. The interface circuit is then configured for a selected one of the application devices in terms of timing control, interrupt control and direct memory access control (DMA). A serial communication controller serializes application data when the serial communication controller receives the second enable signal. The serialized data is then passed to the selected one application device in accordance with the enabled interrupt, the selected one DMA line and the provided timing control rate.

Growing community of inventors

San Diego, CA, United States of America

David L Buck