369 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			Python
		
	
	
	
			
		
		
	
	
			369 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			Python
		
	
	
	
#
 | 
						|
# 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 __future__ import annotations
 | 
						|
 | 
						|
import builtins
 | 
						|
from types import CodeType
 | 
						|
from typing import Any, Callable
 | 
						|
 | 
						|
from . import Image, _imagingmath
 | 
						|
from ._deprecate import deprecate
 | 
						|
 | 
						|
 | 
						|
class _Operand:
 | 
						|
    """Wraps an image operand, providing standard operators"""
 | 
						|
 | 
						|
    def __init__(self, im: Image.Image):
 | 
						|
        self.im = im
 | 
						|
 | 
						|
    def __fixup(self, im1: _Operand | float) -> Image.Image:
 | 
						|
        # 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:
 | 
						|
                msg = f"unsupported mode: {im1.im.mode}"
 | 
						|
                raise ValueError(msg)
 | 
						|
        else:
 | 
						|
            # argument was a constant
 | 
						|
            if isinstance(im1, (int, float)) 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: str,
 | 
						|
        im1: _Operand | float,
 | 
						|
        im2: _Operand | float | None = None,
 | 
						|
        mode: str | None = None,
 | 
						|
    ) -> _Operand:
 | 
						|
        im_1 = self.__fixup(im1)
 | 
						|
        if im2 is None:
 | 
						|
            # unary operation
 | 
						|
            out = Image.new(mode or im_1.mode, im_1.size, None)
 | 
						|
            try:
 | 
						|
                op = getattr(_imagingmath, f"{op}_{im_1.mode}")
 | 
						|
            except AttributeError as e:
 | 
						|
                msg = f"bad operand type for '{op}'"
 | 
						|
                raise TypeError(msg) from e
 | 
						|
            _imagingmath.unop(op, out.getim(), im_1.getim())
 | 
						|
        else:
 | 
						|
            # binary operation
 | 
						|
            im_2 = self.__fixup(im2)
 | 
						|
            if im_1.mode != im_2.mode:
 | 
						|
                # convert both arguments to floating point
 | 
						|
                if im_1.mode != "F":
 | 
						|
                    im_1 = im_1.convert("F")
 | 
						|
                if im_2.mode != "F":
 | 
						|
                    im_2 = im_2.convert("F")
 | 
						|
            if im_1.size != im_2.size:
 | 
						|
                # crop both arguments to a common size
 | 
						|
                size = (
 | 
						|
                    min(im_1.size[0], im_2.size[0]),
 | 
						|
                    min(im_1.size[1], im_2.size[1]),
 | 
						|
                )
 | 
						|
                if im_1.size != size:
 | 
						|
                    im_1 = im_1.crop((0, 0) + size)
 | 
						|
                if im_2.size != size:
 | 
						|
                    im_2 = im_2.crop((0, 0) + size)
 | 
						|
            out = Image.new(mode or im_1.mode, im_1.size, None)
 | 
						|
            try:
 | 
						|
                op = getattr(_imagingmath, f"{op}_{im_1.mode}")
 | 
						|
            except AttributeError as e:
 | 
						|
                msg = f"bad operand type for '{op}'"
 | 
						|
                raise TypeError(msg) from e
 | 
						|
            _imagingmath.binop(op, out.getim(), im_1.getim(), im_2.getim())
 | 
						|
        return _Operand(out)
 | 
						|
 | 
						|
    # unary operators
 | 
						|
    def __bool__(self) -> bool:
 | 
						|
        # an image is "true" if it contains at least one non-zero pixel
 | 
						|
        return self.im.getbbox() is not None
 | 
						|
 | 
						|
    def __abs__(self) -> _Operand:
 | 
						|
        return self.apply("abs", self)
 | 
						|
 | 
						|
    def __pos__(self) -> _Operand:
 | 
						|
        return self
 | 
						|
 | 
						|
    def __neg__(self) -> _Operand:
 | 
						|
        return self.apply("neg", self)
 | 
						|
 | 
						|
    # binary operators
 | 
						|
    def __add__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("add", self, other)
 | 
						|
 | 
						|
    def __radd__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("add", other, self)
 | 
						|
 | 
						|
    def __sub__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("sub", self, other)
 | 
						|
 | 
						|
    def __rsub__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("sub", other, self)
 | 
						|
 | 
						|
    def __mul__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("mul", self, other)
 | 
						|
 | 
						|
    def __rmul__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("mul", other, self)
 | 
						|
 | 
						|
    def __truediv__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("div", self, other)
 | 
						|
 | 
						|
    def __rtruediv__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("div", other, self)
 | 
						|
 | 
						|
    def __mod__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("mod", self, other)
 | 
						|
 | 
						|
    def __rmod__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("mod", other, self)
 | 
						|
 | 
						|
    def __pow__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("pow", self, other)
 | 
						|
 | 
						|
    def __rpow__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("pow", other, self)
 | 
						|
 | 
						|
    # bitwise
 | 
						|
    def __invert__(self) -> _Operand:
 | 
						|
        return self.apply("invert", self)
 | 
						|
 | 
						|
    def __and__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("and", self, other)
 | 
						|
 | 
						|
    def __rand__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("and", other, self)
 | 
						|
 | 
						|
    def __or__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("or", self, other)
 | 
						|
 | 
						|
    def __ror__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("or", other, self)
 | 
						|
 | 
						|
    def __xor__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("xor", self, other)
 | 
						|
 | 
						|
    def __rxor__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("xor", other, self)
 | 
						|
 | 
						|
    def __lshift__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("lshift", self, other)
 | 
						|
 | 
						|
    def __rshift__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("rshift", self, other)
 | 
						|
 | 
						|
    # logical
 | 
						|
    def __eq__(self, other: _Operand | float) -> _Operand:  # type: ignore[override]
 | 
						|
        return self.apply("eq", self, other)
 | 
						|
 | 
						|
    def __ne__(self, other: _Operand | float) -> _Operand:  # type: ignore[override]
 | 
						|
        return self.apply("ne", self, other)
 | 
						|
 | 
						|
    def __lt__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("lt", self, other)
 | 
						|
 | 
						|
    def __le__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("le", self, other)
 | 
						|
 | 
						|
    def __gt__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("gt", self, other)
 | 
						|
 | 
						|
    def __ge__(self, other: _Operand | float) -> _Operand:
 | 
						|
        return self.apply("ge", self, other)
 | 
						|
 | 
						|
 | 
						|
# conversions
 | 
						|
def imagemath_int(self: _Operand) -> _Operand:
 | 
						|
    return _Operand(self.im.convert("I"))
 | 
						|
 | 
						|
 | 
						|
def imagemath_float(self: _Operand) -> _Operand:
 | 
						|
    return _Operand(self.im.convert("F"))
 | 
						|
 | 
						|
 | 
						|
# logical
 | 
						|
def imagemath_equal(self: _Operand, other: _Operand | float | None) -> _Operand:
 | 
						|
    return self.apply("eq", self, other, mode="I")
 | 
						|
 | 
						|
 | 
						|
def imagemath_notequal(self: _Operand, other: _Operand | float | None) -> _Operand:
 | 
						|
    return self.apply("ne", self, other, mode="I")
 | 
						|
 | 
						|
 | 
						|
def imagemath_min(self: _Operand, other: _Operand | float | None) -> _Operand:
 | 
						|
    return self.apply("min", self, other)
 | 
						|
 | 
						|
 | 
						|
def imagemath_max(self: _Operand, other: _Operand | float | None) -> _Operand:
 | 
						|
    return self.apply("max", self, other)
 | 
						|
 | 
						|
 | 
						|
def imagemath_convert(self: _Operand, mode: str) -> _Operand:
 | 
						|
    return _Operand(self.im.convert(mode))
 | 
						|
 | 
						|
 | 
						|
ops = {
 | 
						|
    "int": imagemath_int,
 | 
						|
    "float": imagemath_float,
 | 
						|
    "equal": imagemath_equal,
 | 
						|
    "notequal": imagemath_notequal,
 | 
						|
    "min": imagemath_min,
 | 
						|
    "max": imagemath_max,
 | 
						|
    "convert": imagemath_convert,
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
def lambda_eval(
 | 
						|
    expression: Callable[[dict[str, Any]], Any],
 | 
						|
    options: dict[str, Any] = {},
 | 
						|
    **kw: Any,
 | 
						|
) -> Any:
 | 
						|
    """
 | 
						|
    Returns the result of an image function.
 | 
						|
 | 
						|
    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multi-band
 | 
						|
    images, use the :py:meth:`~PIL.Image.Image.split` method or
 | 
						|
    :py:func:`~PIL.Image.merge` function.
 | 
						|
 | 
						|
    :param expression: A function that receives a dictionary.
 | 
						|
    :param options: Values to add to the function's dictionary. Deprecated.
 | 
						|
                    You can instead use one or more keyword arguments.
 | 
						|
    :param **kw: Values to add to the function's dictionary.
 | 
						|
    :return: The expression result. This is usually an image object, but can
 | 
						|
             also be an integer, a floating point value, or a pixel tuple,
 | 
						|
             depending on the expression.
 | 
						|
    """
 | 
						|
 | 
						|
    if options:
 | 
						|
        deprecate(
 | 
						|
            "ImageMath.lambda_eval options",
 | 
						|
            12,
 | 
						|
            "ImageMath.lambda_eval keyword arguments",
 | 
						|
        )
 | 
						|
 | 
						|
    args: dict[str, Any] = ops.copy()
 | 
						|
    args.update(options)
 | 
						|
    args.update(kw)
 | 
						|
    for k, v in args.items():
 | 
						|
        if isinstance(v, Image.Image):
 | 
						|
            args[k] = _Operand(v)
 | 
						|
 | 
						|
    out = expression(args)
 | 
						|
    try:
 | 
						|
        return out.im
 | 
						|
    except AttributeError:
 | 
						|
        return out
 | 
						|
 | 
						|
 | 
						|
def unsafe_eval(
 | 
						|
    expression: str,
 | 
						|
    options: dict[str, Any] = {},
 | 
						|
    **kw: Any,
 | 
						|
) -> Any:
 | 
						|
    """
 | 
						|
    Evaluates an image expression. This uses Python's ``eval()`` function to process
 | 
						|
    the expression string, and carries the security risks of doing so. It is not
 | 
						|
    recommended to process expressions without considering this.
 | 
						|
    :py:meth:`~lambda_eval` is a more secure alternative.
 | 
						|
 | 
						|
    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multi-band
 | 
						|
    images, use the :py:meth:`~PIL.Image.Image.split` method or
 | 
						|
    :py:func:`~PIL.Image.merge` function.
 | 
						|
 | 
						|
    :param expression: A string containing a Python-style expression.
 | 
						|
    :param options: Values to add to the evaluation context. Deprecated.
 | 
						|
                    You can instead use one or more keyword arguments.
 | 
						|
    :param **kw: Values to add to the evaluation context.
 | 
						|
    :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.
 | 
						|
    """
 | 
						|
 | 
						|
    if options:
 | 
						|
        deprecate(
 | 
						|
            "ImageMath.unsafe_eval options",
 | 
						|
            12,
 | 
						|
            "ImageMath.unsafe_eval keyword arguments",
 | 
						|
        )
 | 
						|
 | 
						|
    # build execution namespace
 | 
						|
    args: dict[str, Any] = ops.copy()
 | 
						|
    for k in [*options, *kw]:
 | 
						|
        if "__" in k or hasattr(builtins, k):
 | 
						|
            msg = f"'{k}' not allowed"
 | 
						|
            raise ValueError(msg)
 | 
						|
 | 
						|
    args.update(options)
 | 
						|
    args.update(kw)
 | 
						|
    for k, v in args.items():
 | 
						|
        if isinstance(v, Image.Image):
 | 
						|
            args[k] = _Operand(v)
 | 
						|
 | 
						|
    compiled_code = compile(expression, "<string>", "eval")
 | 
						|
 | 
						|
    def scan(code: CodeType) -> None:
 | 
						|
        for const in code.co_consts:
 | 
						|
            if type(const) is type(compiled_code):
 | 
						|
                scan(const)
 | 
						|
 | 
						|
        for name in code.co_names:
 | 
						|
            if name not in args and name != "abs":
 | 
						|
                msg = f"'{name}' not allowed"
 | 
						|
                raise ValueError(msg)
 | 
						|
 | 
						|
    scan(compiled_code)
 | 
						|
    out = builtins.eval(expression, {"__builtins": {"abs": abs}}, args)
 | 
						|
    try:
 | 
						|
        return out.im
 | 
						|
    except AttributeError:
 | 
						|
        return out
 | 
						|
 | 
						|
 | 
						|
def eval(
 | 
						|
    expression: str,
 | 
						|
    _dict: dict[str, Any] = {},
 | 
						|
    **kw: Any,
 | 
						|
) -> Any:
 | 
						|
    """
 | 
						|
    Evaluates an image expression.
 | 
						|
 | 
						|
    Deprecated. Use lambda_eval() or unsafe_eval() instead.
 | 
						|
 | 
						|
    :param expression: A string containing a Python-style expression.
 | 
						|
    :param _dict: 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.
 | 
						|
 | 
						|
    ..  deprecated:: 10.3.0
 | 
						|
    """
 | 
						|
 | 
						|
    deprecate(
 | 
						|
        "ImageMath.eval",
 | 
						|
        12,
 | 
						|
        "ImageMath.lambda_eval or ImageMath.unsafe_eval",
 | 
						|
    )
 | 
						|
    return unsafe_eval(expression, _dict, **kw)
 |