Three-dimensional reprojected image forming apparatus

Claim 2

An image information processing apparatus comprising: tomographic image forming unit for forming continuous tomographic image data; two-dimensional image memory means for storing the continuous tomographic image data formed by said tomographic image forming unit; two-dimensional image adding means for adding the continuous tomographic image data in an image reprojection direction while offsetting the tomographic images stored in the two-dimensional image memory means; two-dimensional space filtering means for performing space filtering of spaces between the continuous tomographic image data added by said two-dimensional image adding means to interpolate the spaces; and two-dimensional affine transforming means for performing two-dimensional affine transformation of an interpolated image obtained in said two-dimensional space filtering means to obtain a compressed reprojected image; wherein said two-dimensional image adding means include: means for judging whether an indicated reprojecting direction is perpendicular to a slice plane of the tomographic image; and means for adding values at corresponding addresses of all successive tomographic images stored in said image memory means.

Claim 3

The apparatus according to claim 1, wherein said two-dimensional image adding means include: means for calculating offset amounts of projected points on the tomographic images in accordance with an angle defined between a projecting direction and the tomographic images; means for obtaining corresponding pixel points on the tomographic images in accordance with the offset amounts; and means for adding pixel values at the pixel points.

Claim 4

The apparatus according to claim 2, wherein said offset amounts calculating means include means for calculating offset amounts (Δx,Δy) of the projected points: Δx=(D/tanψ)cosθ Δy=(D/tanψ)sinθ where D denotes a distance between two adjacent tomographic images, ψ denotes an angle defined between the reprojecting direction and an tomographic image plane and θ denotes an angle defined between the reprojection direction on the tomographic image plane and x axis; means for executing calculation of: ##EQU10## denotes an image obtained after addition, m denotes number of tomographic images to be added and Gk denotes a Kth tomographic image; and means for executing two-dimensional affine transformation to obtain a reprojection image R(X,Y); ##EQU11##

Claim 5

An image information processing apparatus comprising: a control computer means for controlling an operation of the image information processing apparatus; a system bus connected to the control computer means; tomographic image forming unit connected to the system bus for forming continuous tomographic images data; two-dimensional image memory means connected to the system bus for storing the continuous tomographic images data formed by said tomographic image forming unit; two-dimensional image adding processor connected to said system bus for adding the continuous tomographic images data in an image reprojection direction while offsetting the tomographic images stored in the two-dimensional image memory means under control of said control computer means; two-dimensional space filtering processor connected to said system bus for performing space filtering of dataless spaces between the continuous tomographic images added by said two-dimensional image adding processor to interpolate the spaces under control of said control computer means; and two-dimensional affine transforming processor connected to said system bus for performing two-dimensional affine transformation of an interpolated image obtained in said two-dimensional space filtering processor to obtain a compressed reprojected image.

Claim 6

An image information processing apparatus comprising: a control computer means for controlling an operation of the image information processing apparatus; a system bus connected to the control computer means; tomographic image forming unit connected to the system bus for forming continuous tomographic images data; two-dimensional image memory means connected to the system bus for storing the continuous tomographic images data formed by said tomographic image forming unit; two-dimensional image adding processor connected to said system bus for adding the continuous tomographic images data in an image reprojection direction while offsetting the tomographic images stored in the two-dimensional image memory means under control of said control computer means; two-dimensional space filtering processor connected to said system bus for performing space filtering of dataless spaces between the continuous tomographic images added by said two-dimensional image adding processor to interpolate the spaces under control of said control computer means; and two-dimensional affine transforming processor connected to said system bus for performing two-dimensional affine transformation of an interpolated image obtained in said two-dimensional space filtering processor to obtain a compressed reprojected image.