Digital radiography detector image readout system and process
A radiographic imaging system and digital detector detect extraneous signals during DR detector image readout and compensate or remove extraneous signal artifacts from radiographic images. Novel capture and post processing procedures prevent undesirable noise artifacts from appearing in final radiographic images.
1. A method of radiographic image correction for a digital radiographic detector, the method comprising:
obtaining an exposed image frame;
obtaining an unexposed image frame;
combining the exposed image frame and the unexposed image frame to form a corrected image frame;
obtaining an exposed leakage frame;
obtaining an unexposed leakage frame;
combining the exposed leakage frame and the unexposed leakage frame to form a conditioned null frame; and
combining the corrected image frame and the conditioned null frame to form a final corrected radiographic image.
2. The method of claim 1 , wherein the step of obtaining an unexposed image frame comprises capturing and averaging two or more unexposed image frames to obtain the unexposed image frame, and wherein the step of obtaining an unexposed leakage frame comprises capturing and averaging two or more unexposed leakage frames to obtain the unexposed leakage frame.
3. The method of claim 1 , wherein the step of combining the exposed image frame and the unexposed image frame comprises subtracting the unexposed image frame from the exposed image frame.
4. The method of claim 3 , wherein the step of combining the exposed leakage frame and the unexposed leakage frame comprise: subtracting the unexposed leakage frame from the exposed leakage frame.
5. The method of claim 4 , wherein the step of combining the corrected image frame and the conditioned null frame comprises subtracting the conditioned null frame from the corrected image frame.
6. The method of claim 1 , wherein the exposed image frame comprises an X-ray beam start.
7. The method of claim 1 , wherein the step of combining the corrected image frame and the conditioned null frame to form a final corrected radiographic image is performed in the digital radiographic detector.
8. A method of image correction for a digital radiographic detector, the method comprising:
obtaining at least one exposed image data frame including activating gate lines to read out the at least one exposed image data frame row by row;
obtaining at least one unexposed dark frame including activating the gate lines to read out the at least one unexposed dark frame row by row;
obtaining at least one exposed leakage frame including keeping the gate lines off to read out the at least one exposed leakage frame row by row;
obtaining at least one unexposed dark leakage frame including keeping the gate lines off to read out the at least one unexposed dark leakage frame row by row;
correcting the at least one exposed image data frame using the at least one unexposed dark frame;
correcting the at least one exposed leakage frame using the at least one unexposed dark leakage frame; and
combining the corrected at least one exposed image data frame and the corrected at least one exposed leakage frame to obtain a corrected image frame.
9. The method of claim 8 , further comprising determining x-ray beam on or x-ray beam off using row-to-row comparison of the at least one exposed image data frame.
10. The method of claim 8 , wherein the step of obtaining at least one unexposed dark frame comprises capturing and averaging two or more unexposed dark frames to obtain the at least one unexposed dark frame, and wherein the step of obtaining at least one unexposed dark leakage frame comprises capturing and averaging two or more unexposed dark leakage frames to obtain the at least one unexposed dark leakage frame.
11. The method of claim 8 , wherein the step of correcting the at least one exposed image data frame comprises subtracting the at least one unexposed dark frame from the at least one exposed image data frame.
12. The method of claim 11 , wherein the step of correcting the at least one exposed leakage frame comprises subtracting the at least one unexposed dark leakage frame from the at least one exposed leakage frame.
13. The method of claim 12 , wherein the step of combining the corrected at least one exposed image data frame and the corrected at least one exposed leakage frame comprises subtracting the at least one exposed leakage frame from the corrected at least one exposed image data frame.
14. The method of claim 8 , wherein the at least one exposed image data frame comprises an X-ray beam start.
15. The method of claim 8 , wherein the method is performed in the digital radiographic detector.
16. A digital radiographic detector comprising a program of instructions configured to be executed on a processor in the digital radiographic detector, the program of instructions causing the digital radiographic detector to perform the steps of:
obtaining an exposed image frame;
obtaining an unexposed image frame;
combining the exposed image frame and the unexposed image frame to form a corrected image frame;
obtaining an exposed leakage frame;
obtaining an unexposed leakage frame;
combining the exposed leakage frame and the unexposed leakage frame to form a conditioned null frame; and
combining the corrected image frame and the conditioned null frame to form a final corrected radiographic image.
17. The method of claim 16 , wherein the step of combining the exposed image frame and the unexposed image frame comprises subtracting the unexposed image frame from the exposed image frame.
18. The method of claim 17 , wherein the step of combining the exposed leakage frame and the unexposed leakage frame comprises subtracting the unexposed leakage frame from the exposed leakage frame.
19. The method of claim 18 , wherein the step of combining the corrected image frame and the conditioned null frame comprises subtracting the conditioned null frame from the corrected image frame.