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-rw-r--r--lib/Python/Lib/PIL/ImageMath.py270
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diff --git a/lib/Python/Lib/PIL/ImageMath.py b/lib/Python/Lib/PIL/ImageMath.py
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+#
+# The Python Imaging Library
+# $Id$
+#
+# a simple math add-on for the Python Imaging Library
+#
+# History:
+# 1999-02-15 fl Original PIL Plus release
+# 2005-05-05 fl Simplified and cleaned up for PIL 1.1.6
+# 2005-09-12 fl Fixed int() and float() for Python 2.4.1
+#
+# Copyright (c) 1999-2005 by Secret Labs AB
+# Copyright (c) 2005 by Fredrik Lundh
+#
+# See the README file for information on usage and redistribution.
+#
+
+from PIL import Image
+from PIL import _imagingmath
+
+try:
+ import builtins
+except ImportError:
+ import __builtin__
+ builtins = __builtin__
+
+VERBOSE = 0
+
+
+def _isconstant(v):
+ return isinstance(v, int) or isinstance(v, float)
+
+
+class _Operand:
+ # wraps an image operand, providing standard operators
+
+ def __init__(self, im):
+ self.im = im
+
+ def __fixup(self, im1):
+ # convert image to suitable mode
+ if isinstance(im1, _Operand):
+ # argument was an image.
+ if im1.im.mode in ("1", "L"):
+ return im1.im.convert("I")
+ elif im1.im.mode in ("I", "F"):
+ return im1.im
+ else:
+ raise ValueError("unsupported mode: %s" % im1.im.mode)
+ else:
+ # argument was a constant
+ if _isconstant(im1) and self.im.mode in ("1", "L", "I"):
+ return Image.new("I", self.im.size, im1)
+ else:
+ return Image.new("F", self.im.size, im1)
+
+ def apply(self, op, im1, im2=None, mode=None):
+ im1 = self.__fixup(im1)
+ if im2 is None:
+ # unary operation
+ out = Image.new(mode or im1.mode, im1.size, None)
+ im1.load()
+ try:
+ op = getattr(_imagingmath, op+"_"+im1.mode)
+ except AttributeError:
+ raise TypeError("bad operand type for '%s'" % op)
+ _imagingmath.unop(op, out.im.id, im1.im.id)
+ else:
+ # binary operation
+ im2 = self.__fixup(im2)
+ if im1.mode != im2.mode:
+ # convert both arguments to floating point
+ if im1.mode != "F":
+ im1 = im1.convert("F")
+ if im2.mode != "F":
+ im2 = im2.convert("F")
+ if im1.mode != im2.mode:
+ raise ValueError("mode mismatch")
+ if im1.size != im2.size:
+ # crop both arguments to a common size
+ size = (min(im1.size[0], im2.size[0]),
+ min(im1.size[1], im2.size[1]))
+ if im1.size != size:
+ im1 = im1.crop((0, 0) + size)
+ if im2.size != size:
+ im2 = im2.crop((0, 0) + size)
+ out = Image.new(mode or im1.mode, size, None)
+ else:
+ out = Image.new(mode or im1.mode, im1.size, None)
+ im1.load()
+ im2.load()
+ try:
+ op = getattr(_imagingmath, op+"_"+im1.mode)
+ except AttributeError:
+ raise TypeError("bad operand type for '%s'" % op)
+ _imagingmath.binop(op, out.im.id, im1.im.id, im2.im.id)
+ return _Operand(out)
+
+ # unary operators
+ def __bool__(self):
+ # an image is "true" if it contains at least one non-zero pixel
+ return self.im.getbbox() is not None
+
+ if bytes is str:
+ # Provide __nonzero__ for pre-Py3k
+ __nonzero__ = __bool__
+ del __bool__
+
+ def __abs__(self):
+ return self.apply("abs", self)
+
+ def __pos__(self):
+ return self
+
+ def __neg__(self):
+ return self.apply("neg", self)
+
+ # binary operators
+ def __add__(self, other):
+ return self.apply("add", self, other)
+
+ def __radd__(self, other):
+ return self.apply("add", other, self)
+
+ def __sub__(self, other):
+ return self.apply("sub", self, other)
+
+ def __rsub__(self, other):
+ return self.apply("sub", other, self)
+
+ def __mul__(self, other):
+ return self.apply("mul", self, other)
+
+ def __rmul__(self, other):
+ return self.apply("mul", other, self)
+
+ def __truediv__(self, other):
+ return self.apply("div", self, other)
+
+ def __rtruediv__(self, other):
+ return self.apply("div", other, self)
+
+ def __mod__(self, other):
+ return self.apply("mod", self, other)
+
+ def __rmod__(self, other):
+ return self.apply("mod", other, self)
+
+ def __pow__(self, other):
+ return self.apply("pow", self, other)
+
+ def __rpow__(self, other):
+ return self.apply("pow", other, self)
+
+ if bytes is str:
+ # Provide __div__ and __rdiv__ for pre-Py3k
+ __div__ = __truediv__
+ __rdiv__ = __rtruediv__
+ del __truediv__
+ del __rtruediv__
+
+ # bitwise
+ def __invert__(self):
+ return self.apply("invert", self)
+
+ def __and__(self, other):
+ return self.apply("and", self, other)
+
+ def __rand__(self, other):
+ return self.apply("and", other, self)
+
+ def __or__(self, other):
+ return self.apply("or", self, other)
+
+ def __ror__(self, other):
+ return self.apply("or", other, self)
+
+ def __xor__(self, other):
+ return self.apply("xor", self, other)
+
+ def __rxor__(self, other):
+ return self.apply("xor", other, self)
+
+ def __lshift__(self, other):
+ return self.apply("lshift", self, other)
+
+ def __rshift__(self, other):
+ return self.apply("rshift", self, other)
+
+ # logical
+ def __eq__(self, other):
+ return self.apply("eq", self, other)
+
+ def __ne__(self, other):
+ return self.apply("ne", self, other)
+
+ def __lt__(self, other):
+ return self.apply("lt", self, other)
+
+ def __le__(self, other):
+ return self.apply("le", self, other)
+
+ def __gt__(self, other):
+ return self.apply("gt", self, other)
+
+ def __ge__(self, other):
+ return self.apply("ge", self, other)
+
+
+# conversions
+def imagemath_int(self):
+ return _Operand(self.im.convert("I"))
+
+
+def imagemath_float(self):
+ return _Operand(self.im.convert("F"))
+
+
+# logical
+def imagemath_equal(self, other):
+ return self.apply("eq", self, other, mode="I")
+
+
+def imagemath_notequal(self, other):
+ return self.apply("ne", self, other, mode="I")
+
+
+def imagemath_min(self, other):
+ return self.apply("min", self, other)
+
+
+def imagemath_max(self, other):
+ return self.apply("max", self, other)
+
+
+def imagemath_convert(self, mode):
+ return _Operand(self.im.convert(mode))
+
+ops = {}
+for k, v in list(globals().items()):
+ if k[:10] == "imagemath_":
+ ops[k[10:]] = v
+
+
+def eval(expression, _dict={}, **kw):
+ """
+ Evaluates an image expression.
+
+ :param expression: A string containing a Python-style expression.
+ :param options: Values to add to the evaluation context. You
+ can either use a dictionary, or one or more keyword
+ arguments.
+ :return: The evaluated expression. This is usually an image object, but can
+ also be an integer, a floating point value, or a pixel tuple,
+ depending on the expression.
+ """
+
+ # build execution namespace
+ args = ops.copy()
+ args.update(_dict)
+ args.update(kw)
+ for k, v in list(args.items()):
+ if hasattr(v, "im"):
+ args[k] = _Operand(v)
+
+ out = builtins.eval(expression, args)
+ try:
+ return out.im
+ except AttributeError:
+ return out