Abstract: A method of operating a DR detector including sequentially capturing image frames in the detector that include at least one dark image. The dark image is stored and a statistical measure for a subset of pixels in a captured image frame is compared with the same statistical measure of a subset of pixels in the stored dark image to detect an x-ray beam impacting the detector. An x-ray beam-on condition is indicated if a sufficient difference in intensity between the pixel subsets is detected. At least one more image frame is captured in the detector after detecting the x-ray beam. The current captured image and the at least one more image frame are added and the dark image is subtracted to form the exposed radiographic image.

Abstract: A radiographic imaging system and digital detector detect extraneous signals during DR detector image readout and compensate or remove extraneous signal artifacts from radiographic images. Novel capture and post processing procedures prevent undesirable noise artifacts from appearing in final radiographic images.

Abstract: A method of operating a DR detector including sequentially capturing image frames in the detector that include at least one dark image. The dark image is stored and a statistical measure for a subset of pixels in a captured image frame is compared with the same statistical measure of a subset of pixels in the stored dark image to detect an x-ray beam impacting the detector. An x-ray beam-on condition is indicated if a sufficient difference in intensity between the pixel subsets is detected. At least one more image frame is captured in the detector after detecting the x-ray beam. The current captured image and the at least one more image frame are added and the dark image is subtracted to form the exposed radiographic image.

Abstract: Embodiments of radiographic imaging systems and/or methods can monitor the state of calibration of a digital x-ray detector, the detector including a solid state sensor with a plurality of pixels, an optional scintillating screen and at least one embedded microprocessor. In one embodiment, a method can use a computer or the embedded microprocessor or both, for setting a calibration operating mode of the portable detector; taking a plurality of dark images in the calibration mode; determining a dark difference image between pixel readings between two of the plurality of dark images; identifying pixels in the dark difference image that differ by over a threshold amount from at least some surrounding pixels in the dark difference image as defective pixels.

Abstract: A radiographic imaging system and digital detector detect extraneous signals during DR detector image readout and compensate or remove extraneous signal artifacts from radiographic images. Novel capture and post processing procedures prevent undesirable noise artifacts from appearing in final radiographic images.

Abstract: Embodiments of radiographic imaging systems and/or methods can operate a digital radiography detector in a multiple modes, where characteristics such as an exposure integration time and dark images (e.g., number timing integration time, etc.) for first and second modes are different. The digital radiography detector can be coupled to a memory that can store a first set of one or more calibration maps for the first mode and a second set of one or more calibration maps for the second mode and a processor. In one embodiment, the processor can form a first calibration-corrected exposure image by modifying a first exposure image from the first mode using the first set of calibration maps and a second calibration-corrected exposure image by modifying a second exposure image from the second mode using the second set of calibration maps in combination with calibration maps for the first mode.

Abstract: A system for monitoring the state of calibration of a digital x-ray detector having a solid state sensor with a plurality of pixels, a scintillating screen and at least one embedded microprocessor, the system having means for capturing a digital image and a computer operable during normal diagnostic use of the detector, in cooperation with at least one embedded microprocessor, for performing pixelwise computations on the image and calculating a misregistration metric indicative of movement of the solid state sensor relative to the scintillating screen. A defect metric indicative of abnormal properties of pixels in the solid state sensor is calculated. It is then determined whether one or both of the misregistration metric and the defect metric exceeds a respective, preselected threshold value. The user of the system is alerted to conduct a calibration of the detector when either one or both of the respective threshold values have been exceeded.

Abstract: Embodiments of radiographic imaging systems and/or methods can monitor the state of calibration of a digital x-ray detector, the detector including a solid state sensor with a plurality of pixels, an optional scintillating screen and at least one embedded microprocessor. In one embodiment, a method can use a computer or the embedded microprocessor or both, for setting a calibration operating mode of the portable detector; taking a plurality of dark images in the calibration mode; determining a dark difference image between pixel readings between two of the plurality of dark images; identifying pixels in the dark difference image that differ by over a threshold amount from at least some surrounding pixels in the dark difference image as defective pixels.

Abstract: Embodiments of radiographic imaging systems and/or methods can operate a digital radiography detector in a multiple modes, where characteristics such as an exposure integration time and dark images (e.g., number timing integration time, etc.) for first and second modes are different. The digital radiography detector can be coupled to a memory that can store a first set of one or more calibration maps for the first mode and a second set of one or more calibration maps for the second mode and a processor. In one embodiment, the processor can form a first calibration-corrected exposure image by modifying a first exposure image from the first mode using the first set of calibration maps and a second calibration-corrected exposure image by modifying a second exposure image from the second mode using the second set of calibration maps in combination with calibration maps for the first mode.

Abstract: A method of obtaining recommendations for lowered radiation dose for a type of radiological image, executed at least in part by a computer system, obtains at least one clinical image of at least one patient, taken under a baseline set of exposure conditions, as a basis image. Processing instructions related to image simulation under one or more reduced exposure conditions are obtained. The basis image is processed according to the processing instructions to generate a set of one or more simulation images, each simulation image representative of corresponding reduced exposure conditions. One or more simulation images are displayed to one or more diagnostic practitioners and an evaluation obtained from the one or more practitioners related to at least the quality of the one or more simulation images. At least one recommended reduced exposure condition is generated and electronically stored according to the practitioner evaluation.

Abstract: A system for monitoring the state of calibration of a digital x-ray detector having a solid state sensor with a plurality of pixels, a scintillating screen and at least one embedded microprocessor, the system having means for capturing a digital image and a computer operable during normal diagnostic use of the detector, in cooperation with at least one embedded microprocessor, for performing pixelwise computations on the image and calculating a misregistration metric indicative of movement of the solid state sensor relative to the scintillating screen. A defect metric indicative of abnormal properties of pixels in the solid state sensor is calculated. It is then determined whether one or both of the misregistration metric and the defect metric exceeds a respective, preselected threshold value. The user of the system is alerted to conduct a calibration of the detector when either one or both of the respective threshold values have been exceeded.

Abstract: A method of forming an offset-corrected exposure image includes obtaining an initial exposure image and exposure metadata related to the initial exposure image. An intermediate offset-corrected exposure image is formed by obtaining one or more dark images associated with the initial exposure image and subtracting an averaged value of the one or more dark images from the initial exposure image. The offset-corrected exposure image is obtained by combining an offset adjustment map with the intermediate offset-corrected exposure image.

Abstract: In a method and system for processing a photographic image having lightness values, L*, representing one of the colorimetric values of an original scene, the photographic image is transformed. The transformed image has a gamma as a function of CIE 1976 L*, which includes a dark region having a rising slope, a light region having a falling slope, and a plateau region having a slope constantly within 5 percent of a maximum value in said plateau region. The rising slope is at least twice as large as the absolute value of the falling slope. The plateau region is between 10 L* and 30 L* wide. Gamma is a derivative of visually perceived reproduced CIE 1976 L* versus scene CIE 1976 L*. Gamma has a maximum slope between 1.5 and 2.0.

Abstract: A method of obtaining recommendations for lowered radiation dose for a type of radiological image, executed at least in part by a computer system, obtains at least one clinical image of at least one patient, taken under a baseline set of exposure conditions, as a basis image. Processing instructions related to image simulation under one or more reduced exposure conditions are obtained. The basis image is processed according to the processing instructions to generate a set of one or more simulation images, each simulation image representative of corresponding reduced exposure conditions. One or more simulation images are displayed to one or more diagnostic practitioners and an evaluation obtained from the one or more practitioners related to at least the quality of the one or more simulation images. At least one recommended reduced exposure condition is generated and electronically stored according to the practitioner evaluation.

Abstract: A method of forming an offset-corrected exposure image includes obtaining an initial exposure image and exposure metadata related to the initial exposure image. An intermediate offset-corrected exposure image is formed by obtaining one or more dark images associated with the initial exposure image and subtracting an averaged value of the one or more dark images from the initial exposure image. The offset-corrected exposure image is obtained by combining an offset adjustment map with the intermediate offset-corrected exposure image.

Abstract: A method for transferring data from a digital radiography receiver panel obtains, at the receiver panel, a full-sized set of image data that comprises a diagnostic image for a patient and at least one reference image for dark signal compensation. A wireless transmission channel between the receiver panel and a separate host processor is monitored to obtain a transmission performance measure. The obtained transmission performance measure is compared against a predetermined threshold value. The response to the comparison is either (a) processing at least some portion of the full-sized set of image data at the receiver panel to form a reduced-size set of image data, then wirelessly transmitting the reduced-size set of image data to the host processor; or (b) wirelessly transmitting the full-sized set of image data from the receiver panel to the host processor.

Abstract: A method for providing a reduced exposure value for radiographic imaging obtains a set of flat-field images at two or more exposure values and measures the noise power spectra using the flat field images. At least one noise table is generated according to interpolated noise power spectra for a set of predetermined exposure values. Values from the at least one noise table are applied to a clinical image to form a reduced exposure simulation image. A noise mask is generated according to at least one noise table and the exposure values of the reduced exposure simulation image and added to the reduced exposure simulation image. The reduced exposure simulation image is assessed to generate a desired dose reduction factor.

Abstract: A method for providing a reduced exposure value for radiographic imaging obtains a set of flat-field images at two or more exposure values and measures the noise power spectra using the flat field images. At least one noise table is generated according to interpolated noise power spectra for a set of predetermined exposure values. Values from the at least one noise table are applied to a clinical image to form a reduced exposure simulation image. A noise mask is generated according to at least one noise table and the exposure values of the reduced exposure simulation image and added to the reduced exposure simulation image. The reduced exposure simulation image is assessed to generate a desired dose reduction factor.

Abstract: In a method and system for processing a photographic image having lightness values, L*, representing one of the colorimetric values of an original scene, the photographic image is transformed. The transformed image has a gamma as a function of CIE 1976 L*, which includes a dark region having a rising slope, a light region having a falling slope, and a plateau region having a slope constantly within 5 percent of a maximum value in said plateau region. The rising slope is at least twice as large as the absolute value of the falling slope. The plateau region is between 10 L* and 30 L* wide. Gamma is a derivative of visually perceived reproduced CIE 1976 L* versus scene CIE 1976 L*. Gamma has a maximum slope between 1.5 and 2.0.

Abstract: In a method and system for processing a photographic image having lightness values, L*, representing one of the colorimetric values of an original scene, the photographic image is transformed. The transformed image has a gamma as a function of CIE 1976 L*, which includes a dark region having a rising slope, a light region having a falling slope, and a plateau region having a slope constantly within 5 percent of a maximum value in said plateau region. The rising slope is at least twice as large as the absolute value of the falling slope. The plateau region is between 10 L* and 30 L* wide. Gamma is a derivative of visually perceived reproduced CIE 1976 L* versus scene CIE 1976 L*. Gamma has a maximum slope between 1.5 and 2.0.