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On this page:
Example
Interface
The Color Class
The Brightness Class
The Contrast Class
The Sharpness Class

The ImageEnhance Module

The ImageEnhance module contains a number of classes that can be used for image enhancement.

Example

Vary the Sharpness of an Image
import ImageEnhance

enhancer = ImageEnhance.Sharpness(image)

for i in range(8):
    factor = i / 4.0
    enhancer.enhance(factor).show("Sharpness %f" % factor)

See the enhancer.py demo program in the Scripts directory.

Interface

All enhancement classes implement a common interface, containing a single method:

enhancer.enhance(factor) => image

Returns an enhanced image. The factor is a floating point value controlling the enhancement. Factor 1.0 always returns a copy of the original image, lower factors mean less colour (brightness, contrast, etc), and higher values more. There are no restrictions on this value.

The Color Class

The colour enhancement class is used to adjust the colour balance of an image, in a manner similar to the controls on a colour TV set. This class implements the enhancement interface as described above.

ImageEnhance.Color(image) => Color enhancer instance

Creates an enhancement object for adjusting colour in an image. A factor of 0.0 gives a black and white image, a factor of 1.0 gives the original image.

The Brightness Class

The brightness enhancement class is used to control the brightness of an image.

ImageEnhance.Brightness(image) => Brightness enhancer instance

Creates an enhancement object for adjusting brightness in an image. A factor of 0.0 gives a black image, factor 1.0 gives the original image.

The Contrast Class

The contrast enhancement class is used to control the contrast of an image, similar to the contrast control on a TV set.

ImageEnhance.Contrast(image) => Contrast enhancer instance

Creates an enhancement object for adjusting contrast in an image. A factor of 0.0 gives an solid grey image, factor 1.0 gives the original image.

The Sharpness Class

The sharpness enhancement class is used to control the sharpness of an image.

ImageEnhance.Sharpness(image) => Sharpness enhancer instance

Creates an enhancement object for adjusting the sharpness of an image. The factor 0.0 gives a blurred image, 1.0 gives the original image, and a factor of 2.0 gives a sharpened image.

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