Out of view CT scan reconstruction
A computer-implemented method and system of CT reconstruction can include receiving one or more CT projection images; performing smooth filtering on the one or more CT projection images to generate one or more smooth boundary filtered images; and back-projecting the one or more smooth boundary filtered images.
1 . A computer-implemented method of CT reconstruction, comprising:
receiving one or more CT projection images, each of the one or more CT projection images comprising one or more pixel rows, each pixel row comprising a first detector pixel and a last detector pixel;
generating a mirror image of one or more rows of the one or more CT projection images;
adding the mirror image of a particular row before the first detector pixel and after the last detector pixel of the particular row to provide a smoothed row;
performing filtering on the one or more CT projection images to generate one or more smooth boundary filtered images; and
back-projecting the one or more smooth boundary filtered images.
2 . The method of claim 1 , wherein back-projecting comprises augmented back-projecting.
3 . The method of claim 2 , wherein augmented back-projecting comprises not zeroing out regions outside of the view cylinder.
4 . The method of claim 2 , wherein augmented back-projecting comprises back-projecting a volume outside of a view cylinder boundary.
5 . The method of claim 1 , wherein the one or more pixel rows comprise pixel intensity values.
6 . The method of claim 1 , wherein the number of pixels in the mirror image is at least the same as a detector width.
7 . The method of claim 1 , wherein performing filtering comprises applying a filter function to the one or more smoothed rows to provide one or more smooth filtered CT projection images.
8 . A system to CT reconstruct images, comprising:
a processor;
a computer-readable storage medium comprising instructions executable by the processor to perform steps comprising:
receiving one or more CT projection images, each of the one or more CT projection images comprising one or more pixel rows, each pixel row comprising a first detector pixel and a last detector pixel;
generating a mirror image of one or more rows of the one or more CT projection images;
adding the mirror image of a particular row before the first detector pixel and after the last detector pixel of the particular row to provide a smoothed row;
performing filtering on the one or more CT projection images to generate one or more smooth boundary filtered images; and
back-projecting the one or more smooth boundary filtered images.
9 . The system of claim 8 , wherein back-projecting comprises augmented back-projecting.
10 . The system of claim 9 , wherein augmented back-projecting comprises not zeroing out regions outside of the view cylinder.
11 . The system of claim 9 , wherein augmented back-projecting comprises back-projecting a volume outside of a view cylinder boundary.
12 . The system of claim 1 , wherein the one or more pixel rows comprise pixel intensity values.
13 . The system of claim 8 , wherein the number of pixels in the mirror image is at least the same as a detector width.
14 . The system of claim 8 , wherein performing filtering comprises applying a filter function to the one or more smoothed rows to provide one or more smooth filtered CT projection images.
15 . A non-transitory computer readable medium storing executable computer program instructions for CT reconstruction, the computer program instructions comprising instructions for: receiving one or more CT projection images, each of the one or more CT projection images comprising one or more pixel rows, each pixel row comprising a first detector pixel and a last detector pixel; generating a mirror image of one or more rows of the one or more CT projection images; adding the mirror image of a particular row before the first detector pixel and after the last detector pixel of the particular row to provide a smoothed row; performing filtering on the one or more CT projection images to generate one or more smooth boundary filtered images; and back-projecting the one or more smooth boundary filtered images.
16 . The medium of claim 15 , wherein back-projecting comprises augmented back-projecting.
17 . The medium of claim 16 , wherein augmented back-projecting comprises not zeroing out regions outside of the view cylinder.
18 . The medium of claim 16 , wherein augmented back-projecting comprises back-projecting a volume outside of a view cylinder boundary.
19 . The medium of claim 15 , wherein the one or more pixel rows comprise pixel intensity values.
20 . The medium of claim 15 , wherein the number of pixels in the mirror image is at least the same as a detector width.