Abstract: Among other things, one or more techniques and/or systems are described for resetting an integration circuit (206) of a detector cell or an electronics arrangement (200) thereof. When a voltage signal output by the integration circuit (206) exceeds a specified threshold (e.g., indicating that a specified number of radiation photons have been detected), a charge injection circuit (208) is configured to inject charge into the integration circuit (206). The injected charge is typically opposite in polarity to stored charge that is stored by a capacitor (214) of the integration circuit (206) and is configured to counteract the stored charge. In this way, a voltage potential at the capacitor (214) decreases, causing the voltage signal output by the integration circuit (206) to decrease.

Abstract: Among other things, one or more techniques and/or systems are described for resetting an integration circuit (206) of a detector cell or an electronics arrangement (200) thereof. When a voltage signal output by the integration circuit (206) exceeds a specified threshold (e.g., indicating that a specified number of radiation photons have been detected), a charge injection circuit (208) is configured to inject charge into the integration circuit (206). The injected charge is typically opposite in polarity to stored charge that is stored by a capacitor (214) of the integration circuit (206) and is configured to counteract the stored charge. In this way, a voltage potential at the capacitor (214) decreases, causing the voltage signal output by the integration circuit (206) to decrease.

Abstract: Among other things, one or more techniques and/or systems are described for counting detection events on a detector cell of a photon counting detector array. An electronics arrangement of the detector cell comprises a digital discriminator which is configured according to an impulse response of the detector cell or, more particularly, an impulse response of a radiation detection element of the detector cell (e.g., where the radiation detection element is configured to convert energy of the radiation photon into electrical charge). The digital discriminator is configured to analyze a digital representation of a voltage signal of the detector cell and to compare a result of the analysis to one or more metrics derived based upon the impulse response of the detector cell to identify voltage pulses of the voltage signal that are indicative of detection events.

Abstract: Radiation flux can be adjusted “on the fly” as an object (204) is being scanned in a security examination apparatus. Adjustments are made to the radiation flux based upon radiation incident on a first radiation detector (226) in an upstream portion (233) of an examination region. The object under examination is thus exposed to different radiation flux in coordination with a downstream motion (235) of the object relative to a second radiation detector (228). The radiation flux is adjusted so that a sufficient number of x-rays (that traverse the object) are incident on the second radiation detector. Images of the object can then be generated based upon data from the second radiation detector, where these images are thus of a desired/higher quality.

Abstract: Among other things, one or more techniques and/or systems are described for counting detection events on a detector cell of a photon counting detector array. An electronics arrangement of the detector cell comprises a digital discriminator which is configured according to an impulse response of the detector cell or, more particularly, an impulse response of a radiation detection element of the detector cell (e.g., where the radiation detection element is configured to convert energy of the radiation photon into electrical charge). The digital discriminator is configured to analyze a digital representation of a voltage signal of the detector cell and to compare a result of the analysis to one or more metrics derived based upon the impulse response of the detector cell to identify voltage pulses of the voltage signal that are indicative of detection events.

Abstract: One or more techniques and/or systems for combining images of objects are disclosed where an image of a first object is to be inserted into an image of a second object in such a manner as to make the insertion substantially undetectable by a human observer of the combined image. An object generator generates a substantially artifact free image of a first object. An object locator orients the first object image according to a desired insertion point in a second object image. A forward projector converts the first object image into projection space data of the first object, and a combiner combines the first object projection space data with the second object projection space data. The combined projection space data is converted to image space data by a reconstructor, and the resulting combined image space data can be displayed on a monitor for human observation.

Abstract: One or more techniques and/or systems for detecting edges in images of objects subjected to imaging using imaging apparatus are disclosed, such that the effect of image noise on the edge detection can be mitigated. Ratios of intensity values (e.g., signal values) for a subject region (e.g., a pixel) and respective adjacent regions are determined. An adaptive threshold value is determined for respective adjacent region pairs. The ratio value is compared to the adaptive threshold value for respective adjacent region pairs, to determine whether an edge is present between the respective adjacent region pairs.

Abstract: Techniques and systems for segmenting one or more objects in a subject image resulting from subjecting one or more objects to imaging using an imaging apparatus are disclosed, such that limitations of image noise, object proximity, image intensity variations, shape complexity, and/or computational resources may be mitigated. Merely border edges of objects in a subject image can be generated, for example, by using edge detection and discarding interior edges. Geometric difference values of the identified boundaries of the objects in the subject image can be calculated. One or more transitions between objects can be identified by using the geometric difference values, for example, which may result in data that represents a location in the image of an object to be segmented.

Abstract: Radiation flux can be adjusted “on the fly” as an object (204) is being scanned in a security examination apparatus. Adjustments are made to the radiation flux based upon radiation incident on a first radiation detector (226) in an upstream portion (233) of an examination region. The object under examination is thus exposed to different radiation flux in coordination with a downstream motion (235) of the object relative to a second radiation detector (228). The radiation flux is adjusted so that a sufficient number of x-rays (that traverse the object) are incident on the second radiation detector. Images of the object can then be generated based upon data from the second radiation detector, where these images are thus of a desired/higher quality.

Abstract: One or more techniques and/or systems for combining images of objects are disclosed where an image of a first object is to be inserted into an image of a second object in such a manner as to make the insertion substantially undetectable by a human observer of the combined image. An object generator generates a substantially artifact free image of a first object. An object locator orients the first object image according to a desired insertion point in a second object image. A forward projector converts the first object image into projection space data of the first object, and a combiner combines the first object projection space data with the second object projection space data. The combined projection space data is converted to image space data by a reconstructor, and the resulting combined image space data can be displayed on a monitor for human observation.

Abstract: One or more techniques and/or systems for detecting edges in images of objects subjected to imaging using imaging apparatus are disclosed, such that the effect of image noise on the edge detection can be mitigated. Ratios of intensity values (e.g., signal values) for a subject region (e.g., a pixel) and respective adjacent regions are determined. An adaptive threshold value is determined for respective adjacent region pairs. The ratio value is compared to the adaptive threshold value for respective adjacent region pairs, to determine whether an edge is present between the respective adjacent region pairs.

Abstract: Techniques and systems for segmenting one or more objects in a subject image resulting from subjecting one or more objects to imaging using an imaging apparatus are disclosed, such that limitations of image noise, object proximity, image intensity variations, shape complexity, and/or computational resources may be mitigated. Merely border edges of objects in a subject image can be generated, for example, by using edge detection and discarding interior edges. Geometric difference values of the identified boundaries of the objects in the subject image can be calculated. One or more transitions between objects can be identified by using the geometric difference values, for example, which may result in data that represents a location in the image of an object to be segmented.

Abstract: Arrangements of X-ray inspection systems are described. An X-ray inspection system may include a shielded housing with a tunnel passageway and entrance and exit ports. The system may include an X-ray inspection station defining a rectilinear coordinate system, an X-ray source, and a detection system for generating images of articles that are located in the inspection station. A conveyor assembly may be included. A plurality of flexible X-ray attenuating, spaced-apart, hanging strips may be distributed within the shielded housing between the ports and across the entire tunnel passageway. The X-ray inspection system may include at least one curtain of flexible X-ray attenuating hanging strips. Each curtain may include a plurality of sets of contiguous strips, the strips of each set being of equal length and distributed across the tunnel passageway. The strips of at least one set are shorter than the strips of at least one other set.

Abstract: A data acquisition system for use in a CT scanner comprises an analog-to-digital converter for generating digital signals in response to analog signals representative of projection data taken at a relatively constant sampling rate; and an interpolation filter for generating projection data for a plurality of predetermined projection angles as a function of the digital signals irrespective of the sampling rate.