# mmneg
Negate an image.

## Synopsis

y = mmneg( f )

Implemented in Python.

### 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])

    >>> print mmneg(f)

    [  0   0 255 245 235 245 255   0   0]

    >>> print mmneg(uint8([0, 1]))

    [255 254]

    >>> print mmneg(int32([0, 1]))

    [ 0 -1]

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

## Source Code

    def mmneg(f):
        y = mmlimits(f)[0] + mmlimits(f)[1] - f
        y = y.astype(f.typecode())
        return y

## 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.

[`mmislesseq`] [Up] [`mmtoggle`] |
Copyright (c) 2003, Roberto A. Lotufo, UNICAMP-University of Campinas; Rubens C. Machado, CenPRA-Renato Archer Research Center.