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The ImageFilter module contains definitions for a pre-defined set of filters, which can be be used in conjuction with the filter method of the Image class.
import ImageFilter im1 = im.filter(ImageFilter.BLUR) im2 = im.filter(ImageFilter.MinFilter(3)) im3 = im.filter(ImageFilter.MinFilter) # same as MinFilter(3)
The current version of the library provides the following set of predefined image enhancement filters:
BLUR, CONTOUR, DETAIL, EDGE_ENHANCE, EDGE_ENHANCE_MORE, EMBOSS, FIND_EDGES, SMOOTH, SMOOTH_MORE, and SHARPEN.
Kernel(size, kernel, scale=None, offset=0)
(New in 1.1.5) Create a convolution kernel of the given size. In the current version, the size must be either (3, 3) or (5, 5), and the kernel argument must be a sequence containing 9 or 25 integer or floating point weights.
If the scale argument is given, the result of applying the kernel to each pixel is divided by the scale value. The default is the sum of the kernel weights.
If the offset argument is given, the value is added to the result, after it has been divided by the scale.
RankFilter(size, rank)
(New in 1.1.5) Create a rank filter of the given size. For each pixel in the input image, the rank filter sorts all pixels in a (size, size) environment, and copies the rank'th value to the output image.
MinFilter(size=3)
(New in 1.1.5) Create a min filter of the given size. For each pixel in the input image, this filter copies the smallest pixel value from a (size, size) environment to the output image.
MedianFilter(size=3)
(New in 1.1.5) Create a min filter of the given size. For each pixel in the input image, this filter copies the smallest pixel value from a (size, size) environment to the output image.
MaxFilter(size=3)
(New in 1.1.5) Create a max filter of the given size. For each pixel in the input image, this filter copies the largest pixel value from a (size, size) environment to the output image.