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mmneg
Negate an image.

Synopsis

function y = mmneg ( f )

Input

f Image Unsigned gray-scale (uint8 or uint16), signed (int32) or binary image

Output

y Image Unsigned gray-scale (uint8 or uint16), signed (int32) or binary image

Description

mmneg returns an image y that is the negation (i.e., inverse or involution) of the image f. In the binary case, y is the complement of f.

Examples

f=uint8([255 255 0 10 20 10 0 255 255]);

y = mmneg(f)

y =
    0    0  255  245  235  245  255    0    0

mmneg(uint8([0, 1]))

ans =
  255  254
Binary image:
a = mmreadgray('gear.tif');

b = mmneg(a);

mmshow(a); 

mmshow(b);
a b
Gray-scale image:
c = mmreadgray('astablet.tif');

d = mmneg(c);

mmshow(c); 

mmshow(d);
c d

Equation

Algorithm

function y = mmneg_equ(f)
  if (mmisbinary(f))
    k = 1;
  elseif (isa(f,'uint8'))
    k = 255;
  else
    k = 65535;
  end 
  y = k - f;

See also

mmfreedom Control automatic data type conversion.
mmsubm Subtraction of two images, with saturation.
mmlimits Get the possible minimum and maximum of an image.
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