Pillow/docs/reference/Image.rst
2018-01-27 00:04:46 -06:00

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.. py:module:: PIL.Image
.. py:currentmodule:: PIL.Image
:py:mod:`Image` Module
======================
The :py:mod:`~PIL.Image` module provides a class with the same name which is
used to represent a PIL image. The module also provides a number of factory
functions, including functions to load images from files, and to create new
images.
Examples
--------
The following script loads an image, rotates it 45 degrees, and displays it
using an external viewer (usually xv on Unix, and the paint program on
Windows).
Open, rotate, and display an image (using the default viewer)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.. code-block:: python
from PIL import Image
im = Image.open("bride.jpg")
im.rotate(45).show()
The following script creates nice thumbnails of all JPEG images in the
current directory preserving aspect ratios with 128x128 max resolution.
Create thumbnails
^^^^^^^^^^^^^^^^^
.. code-block:: python
from PIL import Image
import glob, os
size = 128, 128
for infile in glob.glob("*.jpg"):
file, ext = os.path.splitext(infile)
im = Image.open(infile)
im.thumbnail(size)
im.save(file + ".thumbnail", "JPEG")
Functions
---------
.. autofunction:: open
.. warning::
To protect against potential DOS attacks caused by "`decompression bombs`_" (i.e. malicious files
which decompress into a huge amount of data and are designed to crash or cause disruption by using up
a lot of memory), Pillow will issue a `DecompressionBombWarning` if the image is over a certain
limit. If desired, the warning can be turned into an error with
``warnings.simplefilter('error', Image.DecompressionBombWarning)`` or suppressed entirely with
``warnings.simplefilter('ignore', Image.DecompressionBombWarning)``. See also `the logging
documentation`_ to have warnings output to the logging facility instead of stderr.
.. _decompression bombs: https://en.wikipedia.org/wiki/Zip_bomb
.. _the logging documentation: https://docs.python.org/2/library/logging.html?highlight=logging#integration-with-the-warnings-module
Image processing
^^^^^^^^^^^^^^^^
.. autofunction:: alpha_composite
.. autofunction:: blend
.. autofunction:: composite
.. autofunction:: eval
.. autofunction:: merge
Constructing images
^^^^^^^^^^^^^^^^^^^
.. autofunction:: new
.. autofunction:: fromarray
.. autofunction:: frombytes
.. autofunction:: fromstring
.. autofunction:: frombuffer
Registering plugins
^^^^^^^^^^^^^^^^^^^
.. note::
These functions are for use by plugin authors. Application authors can
ignore them.
.. autofunction:: register_open
.. autofunction:: register_decoder
.. autofunction:: register_mime
.. autofunction:: register_save
.. autofunction:: register_encoder
.. autofunction:: register_extension
The Image Class
---------------
.. autoclass:: PIL.Image.Image
An instance of the :py:class:`~PIL.Image.Image` class has the following
methods. Unless otherwise stated, all methods return a new instance of the
:py:class:`~PIL.Image.Image` class, holding the resulting image.
.. automethod:: PIL.Image.Image.alpha_composite
.. automethod:: PIL.Image.Image.convert
The following example converts an RGB image (linearly calibrated according to
ITU-R 709, using the D65 luminant) to the CIE XYZ color space:
.. code-block:: python
rgb2xyz = (
0.412453, 0.357580, 0.180423, 0,
0.212671, 0.715160, 0.072169, 0,
0.019334, 0.119193, 0.950227, 0 )
out = im.convert("RGB", rgb2xyz)
.. automethod:: PIL.Image.Image.copy
.. automethod:: PIL.Image.Image.crop
.. automethod:: PIL.Image.Image.draft
.. automethod:: PIL.Image.Image.filter
.. automethod:: PIL.Image.Image.getbands
.. automethod:: PIL.Image.Image.getbbox
.. automethod:: PIL.Image.Image.getcolors
.. automethod:: PIL.Image.Image.getdata
.. automethod:: PIL.Image.Image.getextrema
.. automethod:: PIL.Image.Image.getpalette
.. automethod:: PIL.Image.Image.getpixel
.. automethod:: PIL.Image.Image.histogram
.. automethod:: PIL.Image.Image.offset
.. automethod:: PIL.Image.Image.paste
.. automethod:: PIL.Image.Image.point
.. automethod:: PIL.Image.Image.putalpha
.. automethod:: PIL.Image.Image.putdata
.. automethod:: PIL.Image.Image.putpalette
.. automethod:: PIL.Image.Image.putpixel
.. automethod:: PIL.Image.Image.quantize
.. automethod:: PIL.Image.Image.resize
.. automethod:: PIL.Image.Image.remap_palette
.. automethod:: PIL.Image.Image.rotate
.. automethod:: PIL.Image.Image.save
.. automethod:: PIL.Image.Image.seek
.. automethod:: PIL.Image.Image.show
.. automethod:: PIL.Image.Image.split
.. automethod:: PIL.Image.Image.getchannel
.. automethod:: PIL.Image.Image.tell
.. automethod:: PIL.Image.Image.thumbnail
.. automethod:: PIL.Image.Image.tobitmap
.. automethod:: PIL.Image.Image.tobytes
.. automethod:: PIL.Image.Image.tostring
.. automethod:: PIL.Image.Image.transform
.. automethod:: PIL.Image.Image.transpose
.. automethod:: PIL.Image.Image.verify
.. automethod:: PIL.Image.Image.fromstring
.. automethod:: PIL.Image.Image.load
.. automethod:: PIL.Image.Image.close
Attributes
----------
Instances of the :py:class:`Image` class have the following attributes:
.. py:attribute:: filename
The filename or path of the source file. Only images created with the
factory function `open` have a filename attribute. If the input is a
file like object, the filename attribute is set to an empty string.
:type: :py:class: `string`
.. py:attribute:: format
The file format of the source file. For images created by the library
itself (via a factory function, or by running a method on an existing
image), this attribute is set to ``None``.
:type: :py:class:`string` or ``None``
.. py:attribute:: mode
Image mode. This is a string specifying the pixel format used by the image.
Typical values are “1”, “L”, “RGB”, or “CMYK.” See
:ref:`concept-modes` for a full list.
:type: :py:class:`string`
.. py:attribute:: size
Image size, in pixels. The size is given as a 2-tuple (width, height).
:type: ``(width, height)``
.. py:attribute:: width
Image width, in pixels.
:type: :py:class:`int`
.. py:attribute:: height
Image height, in pixels.
:type: :py:class:`int`
.. py:attribute:: palette
Colour palette table, if any. If mode is “P”, this should be an instance of
the :py:class:`~PIL.ImagePalette.ImagePalette` class. Otherwise, it should
be set to ``None``.
:type: :py:class:`~PIL.ImagePalette.ImagePalette` or ``None``
.. py:attribute:: info
A dictionary holding data associated with the image. This dictionary is
used by file handlers to pass on various non-image information read from
the file. See documentation for the various file handlers for details.
Most methods ignore the dictionary when returning new images; since the
keys are not standardized, its not possible for a method to know if the
operation affects the dictionary. If you need the information later on,
keep a reference to the info dictionary returned from the open method.
Unless noted elsewhere, this dictionary does not affect saving files.
:type: :py:class:`dict`