For the whole image, we perform the given arithmetic operation point by point. These operations are useful when we want to change the brightness by exactly a given number of brightness levels, or to adjust the contrast. It is possible to perform:
On every two pixels (equal in position in both images) we perform the given arithmetic operation. The basic arithmetic operations include:
These operations are especially suitable for binary images (only brightness levels 0 and 255). However, they can also be applied to a combination of binary and grayscale images, where the grayscale image can be modified in various ways.
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Image A - blood serum crystalograms
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Image B - synthetic image
A AND B |
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A
OR B A
XOR B
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A
ADD B A
SUB B
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A
MULT B A
DIV B
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MIN(A,B)
MAX(A,B)
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A
AVE B A
OVERLAY B
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WEIGHT - 25% A + 75% B
Operace WEIGHT - 75% A + 25% B |
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