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# | |
# The Python Imaging Library. | |
# $Id$ | |
# | |
# transform wrappers | |
# | |
# History: | |
# 2002-04-08 fl Created | |
# | |
# Copyright (c) 2002 by Secret Labs AB | |
# Copyright (c) 2002 by Fredrik Lundh | |
# | |
# See the README file for information on usage and redistribution. | |
# | |
from __future__ import annotations | |
from typing import Any, Sequence | |
from . import Image | |
class Transform(Image.ImageTransformHandler): | |
"""Base class for other transforms defined in :py:mod:`~PIL.ImageTransform`.""" | |
method: Image.Transform | |
def __init__(self, data: Sequence[Any]) -> None: | |
self.data = data | |
def getdata(self) -> tuple[Image.Transform, Sequence[int]]: | |
return self.method, self.data | |
def transform( | |
self, | |
size: tuple[int, int], | |
image: Image.Image, | |
**options: Any, | |
) -> Image.Image: | |
"""Perform the transform. Called from :py:meth:`.Image.transform`.""" | |
# can be overridden | |
method, data = self.getdata() | |
return image.transform(size, method, data, **options) | |
class AffineTransform(Transform): | |
""" | |
Define an affine image transform. | |
This function takes a 6-tuple (a, b, c, d, e, f) which contain the first | |
two rows from an affine transform matrix. For each pixel (x, y) in the | |
output image, the new value is taken from a position (a x + b y + c, | |
d x + e y + f) in the input image, rounded to nearest pixel. | |
This function can be used to scale, translate, rotate, and shear the | |
original image. | |
See :py:meth:`.Image.transform` | |
:param matrix: A 6-tuple (a, b, c, d, e, f) containing the first two rows | |
from an affine transform matrix. | |
""" | |
method = Image.Transform.AFFINE | |
class PerspectiveTransform(Transform): | |
""" | |
Define a perspective image transform. | |
This function takes an 8-tuple (a, b, c, d, e, f, g, h). For each pixel | |
(x, y) in the output image, the new value is taken from a position | |
((a x + b y + c) / (g x + h y + 1), (d x + e y + f) / (g x + h y + 1)) in | |
the input image, rounded to nearest pixel. | |
This function can be used to scale, translate, rotate, and shear the | |
original image. | |
See :py:meth:`.Image.transform` | |
:param matrix: An 8-tuple (a, b, c, d, e, f, g, h). | |
""" | |
method = Image.Transform.PERSPECTIVE | |
class ExtentTransform(Transform): | |
""" | |
Define a transform to extract a subregion from an image. | |
Maps a rectangle (defined by two corners) from the image to a rectangle of | |
the given size. The resulting image will contain data sampled from between | |
the corners, such that (x0, y0) in the input image will end up at (0,0) in | |
the output image, and (x1, y1) at size. | |
This method can be used to crop, stretch, shrink, or mirror an arbitrary | |
rectangle in the current image. It is slightly slower than crop, but about | |
as fast as a corresponding resize operation. | |
See :py:meth:`.Image.transform` | |
:param bbox: A 4-tuple (x0, y0, x1, y1) which specifies two points in the | |
input image's coordinate system. See :ref:`coordinate-system`. | |
""" | |
method = Image.Transform.EXTENT | |
class QuadTransform(Transform): | |
""" | |
Define a quad image transform. | |
Maps a quadrilateral (a region defined by four corners) from the image to a | |
rectangle of the given size. | |
See :py:meth:`.Image.transform` | |
:param xy: An 8-tuple (x0, y0, x1, y1, x2, y2, x3, y3) which contain the | |
upper left, lower left, lower right, and upper right corner of the | |
source quadrilateral. | |
""" | |
method = Image.Transform.QUAD | |
class MeshTransform(Transform): | |
""" | |
Define a mesh image transform. A mesh transform consists of one or more | |
individual quad transforms. | |
See :py:meth:`.Image.transform` | |
:param data: A list of (bbox, quad) tuples. | |
""" | |
method = Image.Transform.MESH | |