Verfahren zur Bestimmung der gewünschten Bereiche eines Bildsignals und Verfahren zur Bestimmung der gewünschten Bildbereiche

摘要

A method for determining a desired image signal range comprises the steps of carrying out differentiation processing on image signal components of an image signal corresponding to positions located along each of a plurality of lines on a recording medium having a radiation image recorded thereon, which lines include lines extending across an image part corresponding to a radiation blocking material. Absolute values are found from the values resulting from the differentiation processing on the image signal components, which absolute values exceed a threshold value. The image signal components are extracted which correspond to the points on the recording medium associated with the absolute values exceeding the threshold value. A probability density function of the extracted image signal components is generated, and a specific signal value is found which is determined by a signal value corresponding to the maximum value of the probability density function. The signal range on the higher image density side than the specific signal value is determined as a desired image signal range.