401 results about "Motion correction" patented technology

A plurality of projection images are acquired over an angular range during the slow rotation of a C-arm gantry having a source and detector. Phase-specific reconstructions are generated from the plurality of projections, wherein each phase-specific reconstruction is generated generally from projections acquired at or near the respective phase. In one embodiment, a plurality of motion estimates are generated based upon the phase-specific reconstructions. One or more motion-corrected reconstructions may be generated using the respective motion estimates and projections. The motion-corrected reconstructions may be associated to form motion-corrected volume renderings.

An interlace-to-progressive scan conversion system comprises: a spatial line averaging prefilter; a motion estimator; a three-stage adaptive recursive filter. The motion estimator comprises: a 3-D recursive search sub-component having a bilinear interpolator; a motion correction sub-component having an error-function including penalties related to the difference between a given candidate vector and a plurality of neighboring vectors; a block erosion sub-component. The motion estimator assumes that motion is constant between fields. The three-stage adaptive recursive filter comprises: a first stage that selects between using static pixels data and moving pixels data from a next field; a second stage that selects a more valid set of data between motion compensated data from a previous field and the pixels selected by the first stage; a third stage that combines an intra-field interpolation with the more valid set of data selected by the second stage.

An optically-based rigid-body 6-DOF motion tracking system optimized for prospective (real-time) motion correction in Magnetic Resonance Imaging (MRI) applications using a single camera with an on-board image processor, an IR illuminator and optical fiducial targets affixed to a patient. An angle extraction algorithm operated by the on-board image processor utilizes successive approximation to solve the 3-point pose problem for angles close to the origin to achieve convergence to sub-microradian levels. A motion alarm is enabled by a monitor and GUI application in communication with the motion tracking system. A motion correction is enabled for MR scan images taken while operating the motion tracking system wherein an MRI controller is in communication with the motion tracking system.

Motion information of a robot arm stored in a motion information database is acquired. A person manipulates the robot arm, and correction motion information at the time of the motion correction is acquired. An acquiring unit acquires environment information. A motion correction unit corrects the motion information while the robot arm is in motion. A control rule generating unit generates a control rule for allowing the robot arm to automatically operate based on the corrected motion information and the acquired environment information. The motion of the robot arm is controlled based on the generated control rule.

A method of correcting for motion in magnetic resonance images of an object detected by a plurality of signal receiver coils comprising the steps of acquiring a plurality of image signals with the plurality of receiver coils, determining motion between sequential image signals relative to a reference, applying rotation and translation to image signals to align image signals with the reference, determining altered coil sensitivities due to object movement during image signal acquisition, and employing parallel imaging reconstruction of the rotated and translated image signals using the altered coil sensitivities in order to compensate for undersampling in k-space.

A method for correcting a motion related distortion in a sensor measurement comprises establishing a reference position in a borehole. A parameter of interest is measured at a plurality of toolface angles as the tool makes a revolution in the borehole. A distance to a wall of the borehole is measured associated with each parameter of interest measurement. A lateral motion of the tool is measured between each parameter of interest measurement, and a toolface angle of the tool is measured at each parameter of interest measurement. A controller comprising a processor acts according to programmed instructions to calculate a correction to the parameter of interest measurement referenced to the reference position based at least partly on the measured tool motion.

Methods of acquiring magnetic resonance imaging (MRI) data for angiography. The present invention includes novel magnetization preparation schemes where the navigator and fat saturation pulses are executed in steady state after the preparatory pulses in order to minimize the delay between the magnetization preparation and the image echoes. The present invention also provides for improved methods of contrast-enhanced MRI where data are collected along non-linear trajectories through k-space and may also involve novel view ordering. In addition, the present methods employ novel motion corrections that minimize motion artifacts. The present invention further provides novel methods of self-calibrated sensitivity-encoded parallel imaging that allow for accurate and rapid scanning of subjects.

An image data set acquired by an optical coherence tomography (OCT) system is corrected for effects due to motion of the sample. A first set of A-scans is acquired within a time short enough to avoid any significant motion of the sample. A second more extensive set of A-scans is acquired over an overlapping region on the sample. Significant sample motion may occur during acquisition of the second set. A-scans from the first set are matched with A-scans from the second set, based on similarity between the longitudinal optical scattering profiles they contain. Such matched pairs of A-scans are likely to correspond to the same region in the sample. Comparison of the OCT scanner coordinates that produced each A-scan in a matching pair, in conjunction with any shift in the longitudinal scattering profiles between the pair of A-scans, reveals the displacement of the sample between acquisition of the first and second A-scans in the pair. Estimates of the sample displacement are used to correct the transverse and longitudinal coordinates of the A-scans in the second set, to form a motion-corrected OCT data set.

An electronic image stabilizer in a digital camera compensates for camera motion-induced blurriness by segmenting exposure times into multiple shorter exposure times and summing the individual pixels from successive frames after applying an appropriate motion correction. Motion is detected by computing the correlation function between successive images, and compensation is applied by maximizing the correlation function. This avoids the need for mechanical stabilization devices in order to detect or correct the motion as is done in prior art. This method further enables the detection of moving objects in a still background, and correction of blurriness images due to such motion.

A method and related system for generating motion corrected tomographic images includes the steps of illuminating a region of interest (ROI) to be imaged being part of an unrestrained live subject and having at least three spaced apart optical markers thereon. At least one camera is used to obtain images of the markers. Motion data comprising 3D position and orientation of the markers relative to an initial reference position is then calculated. The at least three spaced apart optical markers and the at least one camera are sufficient in quantity and position to avoid multiple epipolar solutions. Motion corrected tomographic data obtained from the ROI using the motion data is then obtained, where motion corrected tomographic images obtained therefrom.

In a multi-shot method for diffusion-weighted imaging in magnetic resonance tomography, the sampling of the k-matrix in the readout direction ensues in segments, and immediately after acquisition of an image data set by readout of one segment by means of echo signals, a navigation data set is acquired by readout of the middle region of the k-matrix at virtually the same time. A movement-corrected diffusion-weighted MRT image is generated by combining of the image data sets with the corresponding navigation data sets and subsequent Fourier transformation.

A method for correcting motion artifacts within a volumetric data set is provided. The method includes obtaining a volumetric data set containing spatial and temporal information regarding an object. The volumetric data set is organized into data slices such that at least two adjacent data slices are representative of a common physical slice within the object at different points in time. The relative motion between adjacent data slices in determined for the slices of the volumetric data set and used to correct for the relative motion between said adjacent slices.

Provided is an image stabilization device including a motion sensor for detecting motion data, an image data display unit for displaying image data, a shake coefficient calculation unit for calculating a shake coefficient indicating intensity of shaking based on time-series motion data detected by the motion sensor, and a motion correction unit for performing control on the image data display unit to move the image data in a direction of cancelling the shaking in a case the shake coefficient calculated by the shake coefficient calculation unit becomes less than a predetermined first threshold.

A head motion tracking method for three-dimensional facial model animation, the head motion tracking method includes acquiring initial facial motion to be fit to an image of a three-dimensional model from an image inputted by a video camera; creating a silhouette of the three-dimensional model and projecting the silhouette; matching the silhouette created from the three-dimensional model with a silhouette acquired by a statistical feature point tracking scheme; and obtaining a motion parameter for the image of the three-dimensional model through motion correction using a texture to perform three-dimensional head motion tracking. In accordance with the present invention, natural three-dimensional facial model animation based on a real image acquired with a video camera can be performed automatically, thereby reducing time and cost.

A magnetic resonance imaging apparatus includes an acquisition unit, a calculation unit, a recalculation unit, a correction unit and a generating unit. The acquisition unit acquires data from plural slices in an object by rotating a zonary region in frequency space by every repetition time. The calculation unit calculates correction parameters for motion correction. The recalculation unit recalculates at least a part of the correction parameters based on relationship between values of the correction parameters and at least one of real-spatial positions and times at which the data is acquired. The correction unit corrects the data using correction parameters including recalculated correction parameters. The generating unit generates image data based on corrected data.

The invention relates to a method and device for reconstructing a 3D image data set of a moving object from a set of projection images, which were recorded at least partially one after the other from different projection directions. The projection images are hereby assigned by ECG gating to a motion phase of the object in each instance and an incomplete 3D image of the object is computed in this motion phase from these few projection images using local tomography. Motion fields are determined from these 3D images and are used during the final 3D image reconstruction for motion corrections.