04952805 is referenced by 21 patents and cites 6 patents.

A method of judging the presence or absence of a limited irradiation field on a recording medium in the case where a radiation image has been recorded on the recording medium comprises the steps of creating a histogram of image signals detected from the recording medium, and dividing the histogram into small regions by an automatic threshold value selecting process using a discriminant criterion or a standard equivalent to the discriminant criterion. The small region located on the lowest signal level side is divided into a lower level division and a higher level division with respect to a mean image signal level of the small region. The limited irradiation field is judged to be present in the case where spread of the lower level division is wider than spread of the higher level division, and judged to be absent in the case where the spread of the lower level division is narrower than the spread of the higher level division.

Title
Method of judging the presence or absence of a limited irradiation field, method of selecting a correct irradiation field, and method of judging correctness or incorrectness of an irradiation field
Application Number
7/234784
Publication Number
4952805
Application Date
August 22, 1988
Publication Date
August 28, 1990
Inventor
Nobuyuki Tanaka
Kanagawa
JP
Agent
Sughrue Mion Zinn Macpeak & Seas
Assignee
Fuji Photo Film
JP
IPC
G03B 42/00
G21K 4/00
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