Pillow/docs/reference/PixelAccess.rst
2018-12-31 11:35:15 +11:00

83 lines
2.3 KiB
ReStructuredText

.. _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.
Example
-------
The following script loads an image, accesses one pixel from it, then
changes it.
.. code-block:: python
from PIL import Image
im = Image.open('hopper.jpg')
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.
.. code-block:: python
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 tuples are accepted
for P 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.