RADIOGRAPHIC MOVING IMAGE SHOOTING DEVICE, METHOD FOR SETTING REGION-OF-INTEREST FOR RADIOGRAPHIC MOVING IMAGE SHOOTING DEVICE, RADIOACTIVE MOVING IMAGE SHOOTING SYSTEM, RADIOGRAPHIC MOVING IMAGE SHOOTING CONTROL PROGRAM, AND MEMORY MEDIUM FOR RADIOGRAPHIC MOVING IMAGE SHOOTING CONTROL PROGRAM

摘要

The purpose of the present invention is to reduce the exposure amount of radiation to a subject without adversely affecting the identification of a region-of-interest mainly in the shooting of a moving image. In a radiographic image shooting system, when a moving image is to be shot, the exposure of radiation to a subject is continued for a longer period compared with that in the shooting of a still image, and therefore it is needed to have the exposure amount of radiation to a subject under consideration. Then, during the setting of a region-of-interest (ROI) which is to be performed before image shooting, the amount of radiation from a radiation source (22A) is reduced as possible (at a level lower than a level in a stationary time), and the compression rate of a dynamic range is increased compared with that in a stationary time in accordance with the distribution of a histogram of an QL value on the basis of the reduced amount of radiation. Consequently, even when the distribution of the QL value is unbalanced, it becomes possible to utilize the dynamic range with economy and it also becomes possible to achieve both the reduction in exposure amount of radiation to a subject through the reduction in the amount of radiation and the highly accurate setting of an ROI.