Image processing apparatus, radiation imaging apparatus, image processing method, and storage medium

An image processing apparatus comprising:

• a dark correction unit configured to obtain a dark corrected image by removing a dark image obtained in a state without radiation irradiation from an object image obtained by radiation irradiation;
• an evaluation value obtaining unit configured to analyze pixel values included in the dark corrected image and obtain an analysis result of the pixel values including a negative pixel value as an evaluation value;
• a statistic information obtaining unit configured to obtain statistic information based on a plurality of evaluation values obtained along with an elapse of time;
• an addition value obtaining unit configured to obtain an addition value used to correct the negative pixel value based on a variation in the evaluation values with respect to the statistic information;
• and
• an adding unit configured to add the addition value to the pixel values of the dark corrected image.

A radiation imaging apparatus comprising:

• a radiation generator configured to generate radiation;
• a detection unit configured to detect the radiation;
• and
• an image processing apparatus configured to process image data detected by the detection unit,
• the image processing apparatus comprising:
• a dark correction unit configured to obtain a dark corrected image by removing a dark image obtained in a state without radiation irradiation from an object image obtained by radiation irradiation;
• an addition value obtaining unit configured to analyze pixel values included in a plurality of dark corrected images and, based on an analysis result of the pixel values including a negative pixel value, obtain an addition value used to correct the negative pixel value;
• and
• an adding unit configured to add the addition value to the pixel values of the dark corrected image.

An image processing method comprising:

• obtaining a dark corrected image by removing a dark image obtained in a state without radiation irradiation from an object image obtained by radiation irradiation;
• analyzing pixel values included in a plurality of dark corrected images and, based on an analysis result of the pixel values including a negative pixel value, obtaining an addition value used to correct the negative pixel value;
• and
• adding the addition value to the pixel values of the dark corrected image.

An image processing method comprising:

• obtaining a dark corrected image by removing a dark image obtained in a state without radiation irradiation from an object image obtained by radiation irradiation;
• analyzing pixel values included in the dark corrected image and obtaining an analysis result of the pixel values including a negative pixel value as an evaluation value;
• obtaining statistic information based on a plurality of evaluation values obtained along with an elapse of time;
• obtaining an addition value used to correct the negative pixel value based on a variation in the evaluation values with respect to the statistic information;
• and
• adding the addition value to the pixel values of the dark corrected image.

A computer-readable storage medium storing a program that causes a computer to function as each unit of an image processing apparatus, the image processing apparatus comprising:

• a dark correction unit configured to obtain a dark corrected image by removing a dark image obtained in a state without radiation irradiation from an object image obtained by radiation irradiation;
• an addition value obtaining unit configured to analyze pixel values included in a plurality of dark corrected images and, based on an analysis result of the pixel values including a negative pixel value, obtain an addition value used to correct the negative pixel value;
• and
• an adding unit configured to add the addition value to the pixel values of the dark corrected image.