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US 4,394,737 AGranted
Method of processing radiographic image
AssigneeFuji Photo Film Co., Ltd.
InventorsTakao Komaki, Seiji Matsumoto
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AssigneeFuji Photo Film Co., Ltd.
InventorsTakao Komaki, Seiji Matsumoto
Estimating the term…
In radiography, a plurality of radiographic films are used for recording radiographic images of an object viewed from the same direction. For instance, a stack of radiographic films stacked together with intensifying screens is exposed to X-rays passing through an object to record the images on the films simultaneously. Alternatively, the plurality of radiographic films are exposed to X-rays passing through the object one by one with the object held still at a position. The images on the plurality of radiographic films are superposed together by electrical signal processing means to obtain an image having averaged density. Then, the gradient of the gradation of the averaged image is enhanced. The radiographic films may be stacked together with self-supporting intensifying screens to reduce the thickness of the stack of the films and intensifying screens when recording the radiographic images. Further, double-side coated intensifying screens may be used together with the stack of the films to reduce the thickness of the stack of the films and intensifying screens when recording the radiographic images.
In radiographic image recording system, a method of processing a radiographic image comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, and enhancing the gradient of gradation of the averaged image.
A method of processing a radiographic image in a radiographic image recording system comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, obtaining an unsharp mask density Dus corresponding to a super-low frequency of said averaged image, and performing an operation represented by a formula of Dorg+.beta.(Dorg-Dus) where Dorg is the density of the image and .beta. is an emphasis coefficient, whereby the gradient of gradation of the averaged image is enhanced with respect to a frequency component above said super-low frequency.
A method of processing a radiographic image in a radiographic image recording system comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, obtaining an unsharp mask density Dus corresponding to a super-low frequency of said radiographic images on the radiographic films, and performing an operation represented by a formula of Dorg+.beta.(Dorg-Dus) where Dorg is the density of the image and .beta. is an emphasis coefficient, whereby the gradient of gradation of the averaged image is enhanced with respect to a frequency component above said super-low frequency.
Dependencies are inferred from the claim text.