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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 . import Image, _imagingmath
- from ._util import py3
-
- try:
- import builtins
- except ImportError:
- import __builtin__
- builtins = __builtin__
-
- VERBOSE = 0
-
-
- def _isconstant(v):
- return isinstance(v, int) or isinstance(v, float)
-
-
- class _Operand(object):
- """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 not py3:
- # 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 not py3:
- # 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
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