Varian Medical Systems, Inc.

Varex Imaging Corporation

Varian Medical Systems Technologies, Inc.

Kevin Matthew Holt

Timothy R Fox

David T Nisius

Gongyin Chen

Paul Bjorkholm

Charles R Smith

Robert Edward Drubka

John Stammetti

Michael Z Duncan

Martin Hu

A control circuit having access to information regarding a plurality of models for different materials along with feasibility criteria processes imaging information for an object (as provided, for example, by a non-invasive imaging apparatus) to facilitate identifying the materials as comprise that object by using the plurality of models to identify candidate materials for portions of the imaging information and then using the feasibility criteria to reduce the candidate materials by avoiding at least one of unlikely materials and combinations of materials to thereby yield useful material-identification information.

Method and apparatus pertaining to non-invasive identification of materials

Radiation scanning systems providing multiple views of an object in different planes and a reconstruction algorithm for reconstructing quasi-three-dimensional images from a limited number of views. A system may include bend magnets to direct accelerated charged particles to multiple targets in different viewing locations. Another system collimates radiation generated by a plurality of radiation sources into multiple beams for scanning an object at multiple angles. The object may be a cargo container, for example. The reconstruction algorithm uses an optimization algorithm and imaging and feasibility models to reconstruct quasi-three-dimensional images from the limited number of views.

Systems and methods for multi-view imaging and tomography

The present invention encompasses methods, apparati, and computer-readable media for correcting spatial artifacts in composite radiographic images of an object (). A method embodiment of the present invention comprises the steps of generating the composite image from a plurality of views of the object (); estimating a shift profile; and re-generating the image by shifting the views using the shift profile.

Correction of spatial artifacts in radiographic images

A control circuit having access to at least one high-energy image of a scene assesses that image to identify candidate obfuscaters as well as candidate obfuscated objects. This control circuit then processes information regarding the candidate objects to identify objects of interest. By one approach these objects of interest are deemed 'of interest' as a function of their being obfuscated in a particular context. By one approach these teachings will accommodate identifying objects as being of interest as a function, at least in part, of the material composition of both the object as well as the visual obfuscater. These teachings also will accommodate peeling away background content/attenuation information in order to separate (and facilitate displaying) a given object in relative isolation from that background content.

Method and apparatus pertaining to identifying objects of interest in a high-energy image

An apparatus reconstructs an image using high energy-based data regarding a scene provides access to first image-capture data regarding the scene that is formed using a first image-capture modality and to second image-capture data that is formed using a second (different) image-capture modality. A control circuit executes an iterative image reconstruction process that establishes a first and a second image-representation channel, a fidelity error measure that measures inconsistency of the image as compared to first image-capture data and second image-capture data, and a prior-penalty term that scores the image based on a priori likelihood or desirability using, at least in part, for each of a plurality of pixels, a non-separable matrix-penalty of a Jacobian-matrix of the image at that pixel, such as nuclear norm. The control circuit further utilizes, in combination with the foregoing, an iterative process to generate a reconstructed image that at least approximately minimizes a combination of the fidelity error measure and the prior-penalty term.

Apparatus and method for reconstructing an image using high-energy-based data

Relative movement about an axis of rotation is caused as between an energy source/detector array with respect to an object (where the object can comprise either an object to be projected to facilitate a study of the object or a calibration object to be projected as part of calibrating usage of the energy source/detector array). The energy source/detector array are used during this relative movement to scan the object and to obtain corresponding object project data. That object projection data is then used to determine a parameter as corresponds to at least one scanning geometry characteristic as corresponds to using the energy source and the corresponding detector array while causing the aforementioned relative movement to scan the object.

Method and apparatus to facilitate determination of a parameter that corresponds to a scanning geometry characteristic

A control circuit operably couples to a non-invasive imaging system that utilizes a particular corresponding effective spectrum and receives imaging information as pertains to an object being imaged. The control circuit uses that information to identify the particular corresponding spectrum for the corresponding source of radiation by, at least in part, evaluating candidate spectra as a function, at least in part, of physical likelihood (for example, by identifying a spectrum that is physically unlikely or physically impossible). Evaluating the candidate spectra as a function of physical likelihood can comprise evaluating the candidate spectra with respect to regularization, smoothness, being non-negative, normalization characteristics, monotonic characteristics, envelope limitations, quasi-concave characteristics, and/or consistency with one or more physics models of choice to note but a few options in these regards.

Method and apparatus pertaining to using imaging information to identify a spectrum

These various embodiments serve to facilitate improving the accuracy of a computed tomography (CT) process. This can comprise operably coupling at least one calibration phantom to a CT scan table and then, during a CT scan of an object that is disposed on the scan table, also gathering calibration information using that calibration phantom(s). By one approach, this calibration phantom can comprise one or more annular-shaped members. When using a plurality of annular-shaped members, at least some of the annular-shaped members can be disposed concentrically with one another. By one approach, in lieu of the foregoing or in combination therewith, this calibration phantom can comprise one or more pins and/or spherically-shaped members (and/or other shapes of geometric interest). If desired, such spherically-shaped members can be combined with the aforementioned pins.

Method and apparatus pertaining to computed tomography scanning using a calibration phantom

A control circuit accesses image information regarding an image of a target. This information comprises, at least in part, information regarding material content of the target. The control circuit also accesses confidence information regarding at least one degree of confidence as pertains to the target's material content. The control circuit uses this confidence information to facilitate rendering the image such that the rendered image integrally conveys information both about materials included in the target and a relative degree of confidence that the materials are correctly identified.

Method and apparatus pertaining to rendering an image to convey levels of confidence with respect to materials identification

First image data (which comprises a penetrating image of an object formed using a first spectrum) and second image data (which also comprises a penetrating image of this same object formed using a second, different spectrum) is retrieved from memory and fused to facilitate identifying at least one material that comprises at least a part of this object. The aforementioned first spectrum can comprise, for example, a spectrum of x-ray energies having a high typical energy while the second spectrum can comprise a spectrum of x-ray energies with a relatively lower typical energy. By one approach, this process can associate materials as comprise the object with corresponding atomic numbers and hence corresponding elements (such as, for example, uranium, plutonium, and so forth).

Method and apparatus to facilitate using fused images to identify materials

One provides () fan-beam data via a translate-rotate computed tomography acquisition process and then reconstructs () an image from this data without resampling any pixel positions other than to optionally resample pixel positions to compensate for non-uniform translation intervals. These embodiments also provide for reconstructing this image from this data without interpolating any pixel positions other than to optionally interpolate pixel positions as again may be useful to compensate for non-uniform translation intervals.

Method and apparatus to facilitate reconstructing an image using fan-beam data

At least three radiation-detection views are used to facilitate identifying material as comprises an object being assessed along a beam path relative to that object. This comprises developing a first radiation-detection view () as corresponds to the material along the beam path, a second radiation-detection view () as corresponds to the material along substantially the beam path, and at least a third radiation-detection view () as corresponds to the material along substantially the beam path. At least one of the source spectra and detector spectral responses used for these radiation-detection views are different from one another for each view. One then uses () these radiation-detection views to identify the material by, at least in part, differentiating the material from other possible materials.

Method and apparatus to facilitate using multiple radiation-detection views to differentiate one material from another

An image processing apparatus () partitions () an image into a plurality of blocks. For a selected one of these blocks, the apparatus then uses a given available range of grayscale level values to determine () grayscale level values for image data in the selected block to provide corresponding determined grayscale level values. At least some of these determined grayscale level values are then transformed () to thereby use an altered amount of the given available range of grayscale level values to thereby provide rescaled grayscale level values for the selected block.

Method and apparatus to facilitate transforming grayscale level values

The provision of calibration information for a given high energy-based scanner having a plurality of detectors can comprise forming () detector-level calibration information for that scanner. This can comprise calculating () a theoretical trajectory as pertains to relative movement as between the plurality of detectors and a calibration object as a function of known geometry parameters for this particular scanner and then causing () relative movement as between this plurality of detectors and a calibration object to develop a corresponding observed trajectory for the calibration object. These teachings then provide for determining (), for each of at least some of the plurality of detectors, a value that corresponds to a difference between the theoretical trajectory and the observed trajectory to thereby provide the detector-level calibration information.

Method and apparatus to facilitate forming detector-level calibration information for a high energy-based scanner

A method of and apparatus for automatically calibrating a computed tomography ('CT') scanning system () is provided including providing () a calibration object () substantially centered on a translating table () for passing through the CT system (). The system () scans () the calibration object () and provides () a preliminary representation such as a display () of a sorted sinogram of the object (). From that preliminary representation, the system () determines intercept-related and/or slope-related values for at least a portion (or) of the preliminary representation and uses these values to calculate () one or more predetermined calibrations values.

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Chicago, IL, United States of America

Kevin Matthew Holt