Abstract: Systems and methods for allocating display colors to thermal image intensity data acquired by thermal band photodetectors. Intensity data from the photodetectors corresponding to scene temperature is converted to a digital value within an analog to digital conversion (ADC) range. The full ADC range may be divided into two or more sub-ranges. In one sub-range, intensity values within that sub-range are assigned display colors from a first color table utilizing one or more Histogram Equalization (HE) techniques. In another sub-range, specific display values from a color table different from the first may be are assigned to specific intensity values. Lower temperatures may be assigned colors using HE and higher temperatures are assigned specific colors corresponding to specific temperatures. Such an arrangement is particularly applicable to thermal imaging use by firefighters because the arrangement allows them to determine temperature directly from displayed color for potentially dangerous temperatures.

Abstract: Systems and methods for allocating display colors to thermal image intensity data acquired by thermal band photodetectors are described. The intensity data from the photodetectors, which corresponds to the scene temperature, is usually converted to a digital value falling within the range of the analog to digital conversion (ADC). The full ADC range may be divided into two or more sub-ranges. In at least one sub-range intensity values within that sub-range may be assigned display colors from a first color table utilizing one or more Histogram Equalization (HE) techniques. In at least one other sub-range, specific display values from a color table different from the first may be assigned to specific intensity values. In some embodiments, the HE assigned sub-range may be lower in intensity than the specific assigned sub-range.

Abstract: A method for offset correction in an imaging system comprising acquiring image data representative of at least a portion of a frame of pixel intensity values from the detector array at two times with a shutter closed. The method includes determining an offset value function for individual pixels based on the image data acquired with the shutter closed. The method includes acquiring subsequent scene image data with the shutter open, and adjusting the scene image data relative to the flat field as predicted by the offset value function at the time the scene image data was acquired to correct for offset drift of the imaging system. In some embodiments, the imaging array is an infrared Focal Plane Array (IR FPA) in a thermal imaging camera.

Abstract: A method and an imaging system for adaptive shutter control wherein an imaging system can be configured to actuate a calibration element at various times and develop an offset correction or Non-Uniformity Correction (NUC). The system control processing units may acquire information derived from calibration data, regular imaging data or external data, which may be correlated with how fast the NUC is changing over time. How often calibration element is actuated may be adaptively determined from the correlating information and the actuation times may be adaptively controlled to optimally actuate as needed. In some embodiments the calibration element may be a shutter and calibration activation may include closing the shutter and providing a flat field image for calibration purposes.

Abstract: A method and an imaging system for adaptive shutter control wherein an imaging system can be configured to actuate a calibration element at various times and develop an offset correction or Non-Uniformity Correction (NUC). The system control processing units may acquire information derived from calibration data, regular imaging data or external data, which may be correlated with how fast the NUC is changing over time. How often calibration element is actuated may be adaptively determined from the correlating information and the actuation times may be adaptively controlled to optimally actuate as needed. In some embodiments the calibration element may be a shutter and calibration activation may include closing the shutter and providing a flat field image for calibration purposes.

Abstract: A method for offset correction in an imaging system comprising acquiring image data representative of at least a portion of a frame of pixel intensity values from the detector array at two times with a shutter closed. The method includes determining an offset value function for individual pixels based on the image data acquired with the shutter closed. The method includes acquiring subsequent scene image data with the shutter open, and adjusting the scene image data relative to the flat field as predicted by the offset value function at the time the scene image data was acquired to correct for offset drift of the imaging system. In some embodiments, the imaging array is an infrared Focal Plane Array (IR FPA) in a thermal imaging camera.