Method and system for removing scatter and veiling glate and other artifacts in digital radiography

Claim 1

A method for reconstructing an image obtained from plural sequential radiographic exposures of an object using a multiple slit beam scanning system including a radiation source for radiating the object, a multiple slit beam scanning assembly positioned between the source and the object, and means for performing plural successive image acquisition steps for acquiring successive frames of original image data, wherein the original image data of each successive frame is in the form of plural pixels and corresponds to radiation passing through the scanning assembly and the object at respective of successive image acquisition steps, comprising the following steps: producing relative movement between the source and the scanning assembly; performing plural successive image acquisitioin steps during production of said relative movement, wherein original image data are acquired for each pixel at each of said successive image acquisition steps during production of said relative movement; determining for each pixel a minimum pixel value of original image data acquired during the successive image acquisition steps; comparing the image data of each pixel acquired at each of the image acquisition steps with a respective comparison cutoff value which bears a predetermined relationship to the minimum value for each pixel determined in said determining step; summing for each pixel only the values of original image data acquired during the plural image acquisition steps which exceed said cutoff value as determined in the comparing step; and outputting a reconstructed image data based at least in part on the sums produced in said summing step.

Claim 2

A method for reconstructing an image obtained from plural sequential radiographic exposures of an object using a multiple slit beam scanning system including a radiation source for radiating the object, a multiple slit beam scanning assembly positioned between the source and the object, and means for performing plural successive image acquisition steps for acquiring successive frames of original image data, wherein the original image data of each successive frame is in the form of plural pixels and corresponds to radiation passing through the scanning assembly and the object at respective of successive image acquisition steps, comprising the following steps: producing relative movement between the source and the scanning assembly; performing plural successive image acquisitioin steps during production of said relative movement, wherein original image data are acquired for each pixel at each of said successive image acquisition steps during production of said relative movement; determining for each pixel a minimum pixel value of original image data acquired during the successive image acquisition steps; comparing the image data of each pixel acquired at each of the image acquisition steps with a respective comparison cutoff value which bears a predetermined relationship to the minimum value for each pixel determined in said determining step; summing for each pixel only the values of original image data acquired during the plural image acquisition steps which exceed said cutoff value as determined in the comparing step; and outputting a reconstructed image data based at least in part on the sums produced in said summing step.

Claim 9

A system for reconstructing an image obtained from plural sequential exposures of an object by a radiation source comprising: multiple slit beam scanning means positioned between the source and the object for exposing said object with radiation emanating from said source and passing through said scanning means; means for performing plural successive image acquisition steps in which successive frames of original image data each in the form of plural pixels are acquired at said plural successive image data acquisition steps during relative movement of said source and said scanning means; means for determining for each pixel a minimum value (I min ) of image data acquired during the successive image data acquisition steps; means for comparing the image data of each pixel acquired for each frame with a comparison cutoff value which bears a predetermined relationship to the minimum pixel value for that frame; means for summing for each pixel all of the values of original image data which exceed said cutoff value for all of said frames of original image data; and means for outputting a reconstructed image data based at least in part on the sums produced by said summing means.

Claim 10

A system for reconstructing an image obtained from plural sequential exposures of an object by a radiation source comprising: multiple slit beam scanning means positioned between the source and the object for exposing said object with radiation emanating from said source and passing through said scanning means; means for performing plural successive image acquisition steps in which successive frames of original image data each in the form of plural pixels are acquired at said plural successive image data acquisition steps during relative movement of said source and said scanning means; means for determining for each pixel a minimum value (I min ) of image data acquired during the successive image data acquisition steps; means for comparing the image data of each pixel acquired for each frame with a comparison cutoff value which bears a predetermined relationship to the minimum pixel value for that frame; means for summing for each pixel all of the values of original image data which exceed said cutoff value for all of said frames of original image data; and means for outputting a reconstructed image data based at least in part on the sums produced by said summing means.

Claim 17

A method for reconstructing an image obtained from plural sequential radiographic exposures of an object using a multiple slit beam scanning assembly including a radiation source for radiating the object, a multiple slit beam scanning assembly positioned between the source and the object, means for producing relative movement between the source and the scanning assembly, and means for performing plural successive image acquisition steps in which original image data in the form of plural pixels are acquired at said successive image acquisition steps during relative movement of said source and said scanning assembly, said original image data corresponding to radiation passing through the scanning assembly and the object at each of said image acquisition steps comprising: selecting a slit beam width of said scanning assembly to be narrower than a pixel size of said original image data acquired by said means for performing plural successive image acquisition steps at an image plane of said means for performing plural successive image acquisition steps; producing relative movement between the source and the scanning assembly; producing a series of image data derived from radiation passing through a common slit of the scanning assembly in consecutive image acquisition steps performed by said means for performing plural successive image acquisition steps during relative movement of said source and scanning assembly steps; forming an enlarged pixel matrix by assigning said series of image data to respective series of adjacent pixels arranged in a direction perpendicular to the scanning beams of said scanning assembly in the enlarged pixel matrix; and forming an image based at least in part on said series of image data assigned to said enlarged pixel matrix.

Claim 18

A method for reconstructing an image obtained from plural sequential radiographic exposures of an object using a multiple slit beam scanning assembly including a radiation source for radiating the object, a multiple slit beam scanning assembly positioned between the source and the object, means for producing relative movement between the source and the scanning assembly, and means for performing plural successive image acquisition steps in which original image data in the form of plural pixels are acquired at said successive image acquisition steps during relative movement of said source and said scanning assembly, said original image data corresponding to radiation passing through the scanning assembly and the object at each of said image acquisition steps comprising: selecting a slit beam width of said scanning assembly to be narrower than a pixel size of said original image data acquired by said means for performing plural successive image acquisition steps at an image plane of said means for performing plural successive image acquisition steps; producing relative movement between the source and the scanning assembly; producing a series of image data derived from radiation passing through a common slit of the scanning assembly in consecutive image acquisition steps performed by said means for performing plural successive image acquisition steps during relative movement of said source and scanning assembly steps; forming an enlarged pixel matrix by assigning said series of image data to respective series of adjacent pixels arranged in a direction perpendicular to the scanning beams of said scanning assembly in the enlarged pixel matrix; and forming an image based at least in part on said series of image data assigned to said enlarged pixel matrix.

Claim 20

A system for reconstructing an image obtained from plural sequential exposures of an object by a radiation source, comprising: multiple slit beam scanning means positioned between the source and the object for exposing the object with radiation emanating from said source and passing through said scanning means; means for producing relative movement between the source and the scanning means; means for performing plural successive image acquisition steps in which successive frames of original image data each in the form of a matrix of plural pixels are acquired at each of said plural image data acquisition steps upon relative movements of said source and said scanning means; said scanning means having a slit beam width selected to be narrower than a pixel size of the pixel matrix at an image plane of said means for performing plural image acquisition steps; means for producing based on said original image data a series of image data derived from radiation passing through a common slit of the scanning means in consecutive image acquisition steps; means for forming an enlarged pixel matrix by assigning said series of image data to a respective series of adjacent pixels arranged in a direction perpendicular to the scanning beams of said scanning means in the enlarged pixel matrix; and means for forming an image based at least in part on said series of image data assigned in said enlarged pixel matrix.

Claim 21

A system for reconstructing an image obtained from plural sequential exposures of an object by a radiation source, comprising: multiple slit beam scanning means positioned between the source and the object for exposing the object with radiation emanating from said source and passing through said scanning means; means for producing relative movement between the source and the scanning means; means for performing plural successive image acquisition steps in which successive frames of original image data each in the form of a matrix of plural pixels are acquired at each of said plural image data acquisition steps upon relative movements of said source and said scanning means; said scanning means having a slit beam width selected to be narrower than a pixel size of the pixel matrix at an image plane of said means for performing plural image acquisition steps; means for producing based on said original image data a series of image data derived from radiation passing through a common slit of the scanning means in consecutive image acquisition steps; means for forming an enlarged pixel matrix by assigning said series of image data to a respective series of adjacent pixels arranged in a direction perpendicular to the scanning beams of said scanning means in the enlarged pixel matrix; and means for forming an image based at least in part on said series of image data assigned in said enlarged pixel matrix.