# The PIL.ImageOps Module

(New in 1.1.3) The ImageOps module contains a number of 'ready-made' image processing operations. This module is somewhat experimental, and most operators only work on L and RGB images.

## Module Contents

autocontrast(image, cutoff=0, ignore=None) [#]

  Maximize (normalize) image contrast. This function calculates a histogram of the input image, removes cutoff percent of the lightest and darkest pixels from the histogram, and remaps the image so that the darkest pixel becomes black (0), and the lightest becomes white (255).

  image
    The image to process.
  cutoff
    How many percent to cut off from the histogram.
  ignore
    The background pixel value (use None for no background).
  Returns:
    An image.
colorize(image, black, white) [#]

  Colorize grayscale image. The black and white arguments should be RGB tuples; this function calculates a colour wedge mapping all black pixels in the source image to the first colour, and all white pixels to the second colour.

  image
    The image to colourize.
  black
    The colour to use for black input pixels.
  white
    The colour to use for white input pixels.
  Returns:
    An image.
crop(image, border=0) [#]

  Remove border from image. The same amount of pixels are removed from all four sides. This function works on all image modes.

  image
    The image to crop.
  border
    The number of pixels to remove.
  Returns:
    An image.
deform(image, deformer, resample=Image.BILINEAR) [#]

  Deform the image.

  image
    The image to deform.
  deformer
    A deformer object.
  resample
    What resampling filter to use.
  Returns:
    An image.
equalize(image, mask=None) [#]

  Equalize the image histogram. This function applies a non-linear mapping to the input image, in order to create a uniform distribution of grayscale values in the output image.

  image
    The image to equalize.
  mask
    An optional mask. If given, only the pixels selected by the mask are included in the analysis.
  Returns:
    An image.
expand(image, border=0, fill=0) [#]

  Add border to the image

  image
    The image to expand.
  border
    Border width, in pixels.
  fill
    Pixel fill value (a colour value). Default is 0 (black).
  Returns:
    An image.
fit(image, size, method=Image.NEAREST, bleed=0.0, centering=(0.5, 0.5)) [#]

  Returns a sized and cropped version of the image, cropped to the requested aspect ratio and size.

  The fit function was contributed by Kevin Cazabon.

  size
    The requested output size in pixels, given as a (width, height) tuple.
  method
    What resampling method to use. Default is Image.NEAREST.
  bleed
    Remove a border around the outside of the image (from all four edges. The value is a decimal percentage (use 0.01 for one percent). The default value is 0 (no border).
  centering
    Control the cropping position. Use (0.5, 0.5) for center cropping (e.g. if cropping the width, take 50% off of the left side, and therefore 50% off the right side). (0.0, 0.0) will crop from the top left corner (i.e. if cropping the width, take all of the crop off of the right side, and if cropping the height, take all of it off the bottom). (1.0, 0.0) will crop from the bottom left corner, etc. (i.e. if cropping the width, take all of the crop off the left side, and if cropping the height take none from the top, and therefore all off the bottom).
  Returns:
    An image.
flip(image) [#]

  Flip the image vertically (top to bottom).

  image
    The image to flip.
  Returns:
    An image.
grayscale(image) [#]

  Convert the image to grayscale.

  image
    The image to convert.
  Returns:
    An image.
invert(image) [#]

  Invert (negate) the image.

  image
    The image to invert.
  Returns:
    An image.
mirror(image) [#]

  Flip image horizontally (left to right).

  image
    The image to mirror.
  Returns:
    An image.
posterize(image, bits) [#]

  Reduce the number of bits for each colour channel.

  image
    The image to posterize.
  bits
    The number of bits to keep for each channel (1-8).
  Returns:
    An image.
solarize(image, threshold=128) [#]

  Invert all pixel values above a threshold.

  image
    The image to posterize.
  threshold
    All pixels above this greyscale level are inverted.
  Returns:
    An image.