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Diffstat (limited to 'PIL/ImageFilter.py')
| -rw-r--r-- | PIL/ImageFilter.py | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/PIL/ImageFilter.py b/PIL/ImageFilter.py new file mode 100644 index 0000000..5857686 --- /dev/null +++ b/PIL/ImageFilter.py @@ -0,0 +1,263 @@ +# +# The Python Imaging Library. +# $Id: ImageFilter.py 2134 2004-10-06 08:55:20Z fredrik $ +# +# standard filters +# +# History: +# 1995-11-27 fl Created +# 2002-06-08 fl Added rank and mode filters +# 2003-09-15 fl Fixed rank calculation in rank filter; added expand call +# +# Copyright (c) 1997-2003 by Secret Labs AB. +# Copyright (c) 1995-2002 by Fredrik Lundh. +# +# See the README file for information on usage and redistribution. +# + +class Filter: + pass + +## +# Convolution filter kernel. + +class Kernel(Filter): + + ## + # Create a convolution kernel. The current version only + # supports 3x3 and 5x5 integer and floating point kernels. + # <p> + # In the current version, kernels can only be applied to + # "L" and "RGB" images. + # + # @def __init__(size, kernel, **options) + # @param size Kernel size, given as (width, height). In + # the current version, this must be (3,3) or (5,5). + # @param kernel A sequence containing kernel weights. + # @param **options Optional keyword arguments. + # @keyparam scale Scale factor. If given, the result for each + # pixel is divided by this value. The default is the sum + # of the kernel weights. + # @keyparam offset Offset. If given, this value is added to the + # result, after it has been divided by the scale factor. + + def __init__(self, size, kernel, scale=None, offset=0): + if scale is None: + # default scale is sum of kernel + scale = reduce(lambda a,b: a+b, kernel) + if size[0] * size[1] != len(kernel): + raise ValueError("not enough coefficients in kernel") + self.filterargs = size, scale, offset, kernel + + def filter(self, image): + if image.mode == "P": + raise ValueError("cannot filter palette images") + return apply(image.filter, self.filterargs) + +class BuiltinFilter(Kernel): + def __init__(self): + pass + +## +# Rank filter. + +class RankFilter(Filter): + name = "Rank" + + ## + # Create a rank filter. The rank filter sorts all pixels in + # a window of the given size, and returns the rank'th value. + # + # @param size The kernel size, in pixels. + # @param rank What pixel value to pick. Use 0 for a min filter, + # size*size/2 for a median filter, size*size-1 for a max filter, + # etc. + + def __init__(self, size, rank): + self.size = size + self.rank = rank + + def filter(self, image): + image = image.expand(self.size/2, self.size/2) + return image.rankfilter(self.size, self.rank) + +## +# Median filter. Picks the median pixel value in a window with the +# given size. + +class MedianFilter(RankFilter): + name = "Median" + + ## + # Create a median filter. + # + # @param size The kernel size, in pixels. + + def __init__(self, size=3): + self.size = size + self.rank = size*size/2 + +## +# Min filter. Picks the lowest pixel value in a window with the given +# size. + +class MinFilter(RankFilter): + name = "Min" + + ## + # Create a min filter. + # + # @param size The kernel size, in pixels. + + def __init__(self, size=3): + self.size = size + self.rank = 0 + +## +# Max filter. Picks the largest pixel value in a window with the +# given size. + +class MaxFilter(RankFilter): + name = "Max" + + ## + # Create a max filter. + # + # @param size The kernel size, in pixels. + + def __init__(self, size=3): + self.size = size + self.rank = size*size-1 + +## +# Mode filter. Picks the most frequent pixel value in a box with the +# given size. Pixel values that occur only once or twice are ignored; +# if no pixel value occurs more than twice, the original pixel value +# is preserved. + +class ModeFilter(Filter): + name = "Mode" + + ## + # Create a mode filter. + # + # @param size The kernel size, in pixels. + + def __init__(self, size=3): + self.size = size + def filter(self, image): + return image.modefilter(self.size) + +## +# Blur filter. + +class BLUR(BuiltinFilter): + name = "Blur" + filterargs = (5, 5), 16, 0, ( + 1, 1, 1, 1, 1, + 1, 0, 0, 0, 1, + 1, 0, 0, 0, 1, + 1, 0, 0, 0, 1, + 1, 1, 1, 1, 1 + ) + +## +# Contour filter. + +class CONTOUR(BuiltinFilter): + name = "Contour" + filterargs = (3, 3), 1, 255, ( + -1, -1, -1, + -1, 8, -1, + -1, -1, -1 + ) + +## +# Detail filter. + +class DETAIL(BuiltinFilter): + name = "Detail" + filterargs = (3, 3), 6, 0, ( + 0, -1, 0, + -1, 10, -1, + 0, -1, 0 + ) + +## +# Edge enhancement filter. + +class EDGE_ENHANCE(BuiltinFilter): + name = "Edge-enhance" + filterargs = (3, 3), 2, 0, ( + -1, -1, -1, + -1, 10, -1, + -1, -1, -1 + ) + +## +# Stronger edge enhancement filter. + +class EDGE_ENHANCE_MORE(BuiltinFilter): + name = "Edge-enhance More" + filterargs = (3, 3), 1, 0, ( + -1, -1, -1, + -1, 9, -1, + -1, -1, -1 + ) + +## +# Embossing filter. + +class EMBOSS(BuiltinFilter): + name = "Emboss" + filterargs = (3, 3), 1, 128, ( + -1, 0, 0, + 0, 1, 0, + 0, 0, 0 + ) + +## +# Edge-finding filter. + +class FIND_EDGES(BuiltinFilter): + name = "Find Edges" + filterargs = (3, 3), 1, 0, ( + -1, -1, -1, + -1, 8, -1, + -1, -1, -1 + ) + +## +# Smoothing filter. + +class SMOOTH(BuiltinFilter): + name = "Smooth" + filterargs = (3, 3), 13, 0, ( + 1, 1, 1, + 1, 5, 1, + 1, 1, 1 + ) + +## +# Stronger smoothing filter. + +class SMOOTH_MORE(BuiltinFilter): + name = "Smooth More" + filterargs = (5, 5), 100, 0, ( + 1, 1, 1, 1, 1, + 1, 5, 5, 5, 1, + 1, 5, 44, 5, 1, + 1, 5, 5, 5, 1, + 1, 1, 1, 1, 1 + ) + +## +# Sharpening filter. + +class SHARPEN(BuiltinFilter): + name = "Sharpen" + filterargs = (3, 3), 16, 0, ( + -2, -2, -2, + -2, 32, -2, + -2, -2, -2 + ) |