Patent ID: 8823835

Claim:
An image processing apparatus for radiation images, the apparatus comprising: a condition acquisition unit configured to acquire conditions for performing radiation imaging, including information indicating an anatomical region to be imaged; an image acquisition unit configured to acquire partial images obtained by shooting partial regions of an entire shooting region, respectively, wherein the entire shooting region corresponds to the acquired information indicating an anatomical region to be imaged; a correction unit configured to acquire a correction value for shifting a pixel value of at least one of the partial regions so that a difference between pixel values of regions common to the partial images is reduced; a feature amount acquisition unit configured to acquire a feature amount of at least one of the partial images based on the acquired information indicating an anatomical region to be imaged, wherein the acquired feature amount is for gradation conversion processing; a characteristic acquisition unit configured to acquire a gradation conversion processing characteristic based on the acquired correction value and the acquired feature amount; and an image processing unit configured to perform, based on the acquired correction value and the processing characteristic, image processing on an image acquired by joining the partial images, to acquire a processed image, wherein gradation of the processed image has been converted.