Image processing apparatus, image processing method, and image processing program
An image acquisition unit acquires first and second radiation images from first and second radiation detectors. A first frequency analysis unit generates a first high-frequency component which is a high-frequency component of the first radiation image, and a second frequency analysis unit generates a second high-frequency component and a second low-frequency component which are a high-frequency component and a low-frequency component of the second radiation image. An addition processing unit performs weighting and addition with respect to the first and second high-frequency components to generate an addition high-frequency component, and a synthesis unit synthesizes the addition high-frequency component and the second low-frequency component to generate a processed image.
1. An image processing apparatus comprising:
a processor configured to
acquire two radiation images obtained by radiation rays passed through a subject, having different amounts of radiation,
generate a first high-frequency component which is a high-frequency component of a first radiation image acquired by radiation having a large amount of radiation among the two radiation images,
generate a second high-frequency component which is a high-frequency component of a second radiation image acquired by radiation having a small amount of radiation among the two radiation images and a second low-frequency component which is a low-frequency component of the second radiation image,
perform weighting and addition between corresponding pixels with respect to the first high-frequency component and the second high-frequency component to generate an addition high-frequency component, and
synthesis the addition high-frequency component and the second low-frequency component to generate a processed image.
2. The image processing apparatus according to claim 1 ,
wherein the processor sets a weighting coefficient in performing the weighting and addition on the basis of a pixel value of the first radiation image.
3. The image processing apparatus according to claim 2 ,
wherein the processor sets the weighting coefficient to 0 with respect to a pixel value corresponding to a pixel value that exceeds a saturated pixel value in the first radiation image and sets the weighting coefficient to 1 with respect to a pixel value corresponding to a pixel value that is equal to or smaller the saturated pixel value in the first radiation image, with respect to the first high-frequency component.
4. The image processing apparatus according to claim 3 ,
wherein the processor gradually changes the weighting coefficient in the vicinity of the saturated pixel value.
5. The image processing apparatus according to claim 1 ,
wherein the processor sets the weighting coefficient in performing the weighting and addition on the basis of a characteristic of a radiation detector for acquiring the first radiation image.
6. The image processing apparatus according to claim 1 ,
wherein the processor generates the first high-frequency component in a frequency band according to an imaging portion of the subject, and
wherein the processor generates the second high-frequency component and the second low-frequency component in a frequency band according to an imaging portion of the subject.
7. An image processing method comprising:
acquiring two radiation images obtained by radiation rays passed through a subject, having different amounts of radiation;
generating a first high-frequency component which is a high-frequency component of a first radiation image acquired by radiation having a large amount of radiation among the two radiation images;
generating a second high-frequency component which is a high-frequency component of a second radiation image acquired by radiation having a small amount of radiation among the two radiation images and a second low-frequency component which is a low-frequency component of the second radiation image;
performing weighting and addition between corresponding pixels with respect to the first high-frequency component and the second high-frequency component to generate an addition high-frequency component; and
synthesizing the addition high-frequency component and the second low-frequency component to generate a processed image.
8. A non-transitory computer-readable recording medium having stored therein an image processing program that causes a computer to execute:
a process of acquiring two radiation images obtained by radiation rays passed through a subject, having different amounts of radiation;
a process of generating a first high-frequency component which is a high-frequency component of a first radiation image acquired by radiation having a large amount of radiation among the two radiation images;
a process of generating a second high-frequency component which is a high-frequency component of a second radiation image acquired by radiation having a small amount of radiation among the two radiation images and a second low-frequency component which is a low-frequency component of the second radiation image;
a process of performing weighting and addition between corresponding pixels with respect to the first high-frequency component and the second high-frequency component to generate an addition high-frequency component; and
a process of synthesizing the addition high-frequency component and the second low-frequency component to generate a processed image.