Pillow/docs/reference/PixelAccess.rst
2023-02-24 08:17:10 +11:00

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.. _PixelAccess:
:py:class:`PixelAccess` Class
=============================
The PixelAccess class provides read and write access to
:py:class:`PIL.Image` data at a pixel level.
.. note:: Accessing individual pixels is fairly slow. If you are
looping over all of the pixels in an image, there is likely
a faster way using other parts of the Pillow API.
:mod:`~PIL.Image`, :mod:`~PIL.ImageChops` and :mod:`~PIL.ImageOps`
have methods for many standard operations. If you wish to perform
a custom mapping, check out :py:meth:`~PIL.Image.Image.point`.
Example
-------
The following script loads an image, accesses one pixel from it, then
changes it. ::
from PIL import Image
with Image.open("hopper.jpg") as im:
px = im.load()
print(px[4, 4])
px[4, 4] = (0, 0, 0)
print(px[4, 4])
Results in the following::
(23, 24, 68)
(0, 0, 0)
Access using negative indexes is also possible. ::
px[-1, -1] = (0, 0, 0)
print(px[-1, -1])
:py:class:`PixelAccess` Class
-----------------------------
.. class:: PixelAccess
.. method:: __setitem__(self, xy, color):
Modifies the pixel at x,y. The color is given as a single
numerical value for single band images, and a tuple for
multi-band images
:param xy: The pixel coordinate, given as (x, y).
:param color: The pixel value according to its mode. e.g. tuple (r, g, b) for RGB mode)
.. method:: __getitem__(self, xy):
Returns the pixel at x,y. The pixel is returned as a single
value for single band images or a tuple for multiple band
images
:param xy: The pixel coordinate, given as (x, y).
:returns: a pixel value for single band images, a tuple of
pixel values for multiband images.
.. method:: putpixel(self, xy, color):
Modifies the pixel at x,y. The color is given as a single
numerical value for single band images, and a tuple for
multi-band images. In addition to this, RGB and RGBA tuples
are accepted for P and PA images.
:param xy: The pixel coordinate, given as (x, y).
:param color: The pixel value according to its mode. e.g. tuple (r, g, b) for RGB mode)
.. method:: getpixel(self, xy):
Returns the pixel at x,y. The pixel is returned as a single
value for single band images or a tuple for multiple band
images
:param xy: The pixel coordinate, given as (x, y).
:returns: a pixel value for single band images, a tuple of
pixel values for multiband images.