X-ray imaging apparatus and method of updating a pixel map

1. A method of updating a pixel map, the method comprising:

generating an X-ray transmission image by detecting an X-ray penetrating an object;

determining whether a difference between a value associated with each one of the pixels forming the X-ray transmission image and a value associated with a nearby pixel adjacent to the each one of the pixels is equal to or greater than a predetermined reference value by comparing the value of the each one of the pixels with the value of the nearby pixel;

determining a pixel having a value representing a difference equal to or greater than the reference value as a candidate for a bad pixel among the pixels if the difference is equal to or greater than the reference value;

determining whether the candidate for the bad pixel is the bad pixel; and

updating the pixel map in real time prior to performing image processing on the X-ray transmission image by use of the updated pixel map by showing the determined bad pixel on the pixel map if the candidate for the bad pixel is determined as the bad pixel.

2. The method of claim 1 , wherein the step of determining whether the difference between the value of each one of the pixels forming the X-ray transmission image and the value of a nearby pixel adjacent to the each one of the pixels is equal to or greater than the reference value, includes determining whether a predetermined pixel among the pixels forming the X-ray transmission image is greater in value than the value of an area surrounding the predetermined pixel by the reference value and a value greater than the reference value.

3. The method of claim 2 , wherein the area surrounding the predetermined pixel comprises at least one pixel.

4. The method of claim 1 , wherein the step of determining the pixel having the value representing the difference equal to or greater than the reference value as the candidate for the bad pixel among the pixels if the difference is equal to or greater than the reference value, includes the step of determining a predetermined pixel among the pixels forming the X-ray transmission image as the candidate for the bad pixel if the predetermined pixel is greater in value than a value of an area surrounding the predetermined pixel by the reference value and a value greater than the reference value.

5. The method of claim 1 , wherein the updating of the pixel map by showing the determined bad pixel on the pixel map if the candidate for the bad pixel is determined as the bad pixel comprises:

updating the pixel map by indicating the determined bad pixel as the bad pixel on the pixel map; and

storing the updated pixel map.

6. The method of claim 1 , wherein the value associated with the pixel is a value representing a brightness of the pixel.

7. The method according to claim 1 , wherein prior to determining whether the candidate for the bad pixel is the bad pixel, displaying a message which prompts a selection of whether to perform the determining as to whether the candidate for the bad pixel is the bad pixel.

8. The method of claim 7 , wherein the step of displaying of the message requesting a selection of whether to determine the candidate for the bad pixel as the bad pixel, includes displaying, on a display unit:

a pixel map, which indicates the candidate for the bad pixel such that a user is enabled to verify whether the candidate for the bad pixel corresponds to the bad pixel, and a message, which requests a selection of whether to determine the indicated candidate for the bad pixel as the bad pixel.

9. The method according to claim 1 , wherein the determining that the candidate for the bad pixel is the bad pixel is performed automatically without user intervention.

10. An X-ray imaging apparatus comprising:

a detection unit configured to detect an X-ray penetrating an object and to output an X-ray detection signal; and

a control unit configured to generate an X-ray transmission image of the object from the X-ray detection signal that is output from the detection unit, to determine a candidate for a bad pixel with respect to each one of the pixels forming the X-ray transmission image, to determine whether the candidate for the bad pixel is the bad pixel, and to update a pixel map in real time prior to performing image processing on the X-ray transmission image by use of the updated pixel map by showing the determined bad pixel on the pixel map if the candidate for the bad pixel is determined as the bad pixel.

11. The X-ray imaging apparatus of claim 10 , wherein the control unit determines whether a predetermined pixel of the pixels forming the X-ray transmission image is greater in an associated value than an associated value of an area surrounding the predetermined pixel by a predetermined reference value and a value greater than the reference value, and determines the predetermined pixel as the candidate for the bad pixel if the value of the predetermined pixel is equal to or greater than the value of an area surrounding the predetermined pixel by the reference value and a value greater than the reference value.

12. The X-ray imaging apparatus of claim 11 , wherein the area surrounding the predetermined pixel comprises at least one pixel.

13. The X-ray image apparatus of claim 11 , wherein the value associated with the pixel is a value representing a brightness of the pixel.

14. The X-ray image apparatus of claim 10 , wherein the control unit displays a pixel map, which indicates the candidate for the bad pixel such that a user is enabled to verify whether the candidate for the bad pixel corresponds to the bad pixel, and a message, which requests a selection of whether to determine the indicated candidate for the bad pixel as the bad pixel, on a display unit.

15. The X-ray image apparatus of claim 10 , wherein the control unit updates the pixel map by indicating the determined bad pixel as the bad pixel on the pixel map, and stores the updated pixel map.

16. The X-ray image apparatus of claim 10 , wherein the controller is configured to display a message requesting a selection of whether to determine that the candidate for the bad pixel is the bad pixel.

17. The X-ray image apparatus of claim 10 , wherein the controller is configured to determine automatically whether the candidate for the bad pixel is the bad pixel.