Automatic misregistration correction

Claim 1

A method for correcting for artifacts generated by object motion caused misregistration between different images of the same object, said method comprising of: obtaining data for first and second images of the same object, which may have normally changing and normally non-changing portions; selecting a point on a normally non-changing portion; locating said point in each of said images; the step of locating the point including the steps of: directing a Region-of-Interest (ROI) to encompass a normally non-changing portion in each of said first and second images; determining the density in the ROI in each of said first and second images, determining the density gradients in the ROI in each of said first and second images, determining the amplitudes of the density gradients in the ROI in each of said first and second images, transforming said amplitudes of the density gradients in the ROI in each of said first and second images to quantities that are positive, and determining as the point in each of said first and second images the centers of gravity (COGs) of said quantities within the ROI in each of said first and second images, subtracting coordinates of the COG of one of said images from coordinates of the COG of the other of said images to provide the vector extending between the point in each of said first and second images, and using the vector to move said first and second images relative to each other a distance and direction as determined by said vector.

Claim 2

A method for correcting for artifacts generated by object motion caused misregistration between different images of the same object, said method comprising of: obtaining data for first and second images of the same object, which may have normally changing and normally non-changing portions; selecting a point on a normally non-changing portion; locating said point in each of said images; the step of locating the point including the steps of: directing a Region-of-Interest (ROI) to encompass a normally non-changing portion in each of said first and second images; determining the density in the ROI in each of said first and second images, determining the density gradients in the ROI in each of said first and second images, determining the amplitudes of the density gradients in the ROI in each of said first and second images, transforming said amplitudes of the density gradients in the ROI in each of said first and second images to quantities that are positive, and determining as the point in each of said first and second images the centers of gravity (COGs) of said quantities within the ROI in each of said first and second images, subtracting coordinates of the COG of one of said images from coordinates of the COG of the other of said images to provide the vector extending between the point in each of said first and second images, and using the vector to move said first and second images relative to each other a distance and direction as determined by said vector.

Claim 15

A system for correcting for artifacts generated by object motion caused misregistration between different images of the same object, said system comprising: means for obtaining density data for first and second images of the same object, which may have normally changing and normally non-changing items, means for selecting a point on a normally non-changing item, means for locating said point in each of said images, said means for locating said point comprising means for obtaining density gradients from the density data in a Region of Interest (ROI) similarily placed on both said first and second images means for determining the amplitudes of the density gradients from the density gradients in the ROI similarily placed on both said first and second images, means for transforming the said amplitudes of the density gradients to quantities that are positive, means for determining coordinates of the COGs of said positive quantities within the ROI's, and means for subtracting said coordinates to provide the coordinate components of a vector extending between the points defined by the centers of gravity, and means for using the vector to move the first and second images relative to each other an amount and direction determined by the vector.

Claim 16

A system for correcting for artifacts generated by object motion caused misregistration between different images of the same object, said system comprising: means for obtaining density data for first and second images of the same object, which may have normally changing and normally non-changing items, means for selecting a point on a normally non-changing item, means for locating said point in each of said images, said means for locating said point comprising means for obtaining density gradients from the density data in a Region of Interest (ROI) similarily placed on both said first and second images means for determining the amplitudes of the density gradients from the density gradients in the ROI similarily placed on both said first and second images, means for transforming the said amplitudes of the density gradients to quantities that are positive, means for determining coordinates of the COGs of said positive quantities within the ROI's, and means for subtracting said coordinates to provide the coordinate components of a vector extending between the points defined by the centers of gravity, and means for using the vector to move the first and second images relative to each other an amount and direction determined by the vector.

Claim 32

A method of correcting artifacts generated by object motion caused misregistration between first and second images of the same object, said artifacts appearing on a third image made by merging said first and second images, said method comprising the steps of: obtaining data for first and second images of the same object, which may have normally changing and normally non-changing items; selecting a point on a normally non-changing item, locating said point in each of said images; the step of locating said point on each of said images comprising the steps of: locating an artifact on the third image, selecting a portion of the third image which includes the located artifact, selecting corresponding portions of said first and second images, obtaining the density of said corresponding portions of said first and second image, obtaining the gradients of the obtained density, obtaining the amplitudes of density gradients of the corresponding portions of the first and second images, transforming the said amplitudes of the density gradients to quantitites that are all positive, and and determining the centers of gravity of the positive amplitudes within the corresponding portions, determining differences between the locations of the COGs in each of said first and second images to obtain a vector of the motion causing the misregistration, and using said vector to correct for the misregistration caused by object motion between the acquisition of said first and second images.

Claim 33

A method of correcting artifacts generated by object motion caused misregistration between first and second images of the same object, said artifacts appearing on a third image made by merging said first and second images, said method comprising the steps of: obtaining data for first and second images of the same object, which may have normally changing and normally non-changing items; selecting a point on a normally non-changing item, locating said point in each of said images; the step of locating said point on each of said images comprising the steps of: locating an artifact on the third image, selecting a portion of the third image which includes the located artifact, selecting corresponding portions of said first and second images, obtaining the density of said corresponding portions of said first and second image, obtaining the gradients of the obtained density, obtaining the amplitudes of density gradients of the corresponding portions of the first and second images, transforming the said amplitudes of the density gradients to quantitites that are all positive, and and determining the centers of gravity of the positive amplitudes within the corresponding portions, determining differences between the locations of the COGs in each of said first and second images to obtain a vector of the motion causing the misregistration, and using said vector to correct for the misregistration caused by object motion between the acquisition of said first and second images.

Claim 36

A system for correcting for artifacts generated by object motion caused misregistration between different images of the same object, said system comprising: means for obtaining transmittance data for first and second images of the same object, which may have items normally changing in transmittance and items normally non-changing in transmittance, said artifacts appearing on a third image comprised of a merging of said first and second images, means for selecting a point in a normally non-changing item, means for locating said point in each of said images, said means for locating said point in each of said images comprising: means for selecting a portion of the third images, said portion containing an artifact, means for obtaining gradients of said transmittance data in portions of said first and second images corresponding to said selected portion of said third image, means for obtaining amplitude of the gradients of said transmittance data in the corresponding portions of the first and second images, means for transforming the obtained amplitudes of the gradients to quantities that are all positive, means for reducing the effect of image noise, means for determining centers of gravity (COGs) of said positive amplitudes in regions around said normally non-changing items in the corresponding portions in each of said first and second images, means for determining coordinate differences between the locations of the COGs in each of said images to obtain vector coordinate, of the vector of the motion causing the misregistration, and means for utilizing the vector for moving said first image relative to the second image the amount of the vector in both amplitude and direction to correct for the misregistration.

Claim 37

A system for correcting for artifacts generated by object motion caused misregistration between different images of the same object, said system comprising: means for obtaining transmittance data for first and second images of the same object, which may have items normally changing in transmittance and items normally non-changing in transmittance, said artifacts appearing on a third image comprised of a merging of said first and second images, means for selecting a point in a normally non-changing item, means for locating said point in each of said images, said means for locating said point in each of said images comprising: means for selecting a portion of the third images, said portion containing an artifact, means for obtaining gradients of said transmittance data in portions of said first and second images corresponding to said selected portion of said third image, means for obtaining amplitude of the gradients of said transmittance data in the corresponding portions of the first and second images, means for transforming the obtained amplitudes of the gradients to quantities that are all positive, means for reducing the effect of image noise, means for determining centers of gravity (COGs) of said positive amplitudes in regions around said normally non-changing items in the corresponding portions in each of said first and second images, means for determining coordinate differences between the locations of the COGs in each of said images to obtain vector coordinate, of the vector of the motion causing the misregistration, and means for utilizing the vector for moving said first image relative to the second image the amount of the vector in both amplitude and direction to correct for the misregistration.