| 摘要 |
<p>The first step (10) in the method is to obtain an output from the image sensor when the radiation source is inactive, then to obtain (11) one or more reference images of known objects. Then (12) image offsets and mean gain values are determined and at least one image of the object to be measured is obtained (13), with uniform attenuation in the case of an X-ray detector and uniform attenuation for a gamma ray detector. A first mean value and standard deviation for the whole image of the object being measured are then determined (14). As a function of pixel grey level and the calculated mean and standard deviations, a first confidence map is built up (17) which can be used for correction.</p> |
