Pillow/docs/releasenotes/7.0.0.rst
2019-12-21 03:16:42 +03:00

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7.0.0
-----
Backwards Incompatible Changes
==============================
PILLOW_VERSION constant
^^^^^^^^^^^^^^^^^^^^^^^
``PILLOW_VERSION`` has been removed. Use ``__version__`` instead.
PIL.*ImagePlugin.__version__ attributes
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The version constants of individual plugins have been removed. Use ``PIL.__version__``
instead.
=============================== ================================= ==================================
Removed Removed Removed
=============================== ================================= ==================================
``BmpImagePlugin.__version__`` ``Jpeg2KImagePlugin.__version__`` ``PngImagePlugin.__version__``
``CurImagePlugin.__version__`` ``JpegImagePlugin.__version__`` ``PpmImagePlugin.__version__``
``DcxImagePlugin.__version__`` ``McIdasImagePlugin.__version__`` ``PsdImagePlugin.__version__``
``EpsImagePlugin.__version__`` ``MicImagePlugin.__version__`` ``SgiImagePlugin.__version__``
``FliImagePlugin.__version__`` ``MpegImagePlugin.__version__`` ``SunImagePlugin.__version__``
``FpxImagePlugin.__version__`` ``MpoImagePlugin.__version__`` ``TgaImagePlugin.__version__``
``GdImageFile.__version__`` ``MspImagePlugin.__version__`` ``TiffImagePlugin.__version__``
``GifImagePlugin.__version__`` ``PalmImagePlugin.__version__`` ``WmfImagePlugin.__version__``
``IcoImagePlugin.__version__`` ``PcdImagePlugin.__version__`` ``XbmImagePlugin.__version__``
``ImImagePlugin.__version__`` ``PcxImagePlugin.__version__`` ``XpmImagePlugin.__version__``
``ImtImagePlugin.__version__`` ``PdfImagePlugin.__version__`` ``XVThumbImagePlugin.__version__``
``IptcImagePlugin.__version__`` ``PixarImagePlugin.__version__``
=============================== ================================= ==================================
PyQt4 and PySide
^^^^^^^^^^^^^^^^
Qt 4 reached end-of-life on 2015-12-19. Its Python bindings are also EOL: PyQt4 since
2018-08-31 and PySide since 2015-10-14.
Support for PyQt4 and PySide has been removed from ``ImageQt``. Please upgrade to PyQt5
or PySide2.
Setting the size of TIFF images
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Setting the size of a TIFF image directly (eg. ``im.size = (256, 256)``) throws
an error. Use ``Image.resize`` instead.
Default resampling filter
^^^^^^^^^^^^^^^^^^^^^^^^^
The default resampling filter has been changed to the high-quality convolution
``Image.BICUBIC`` instead of ``Image.NEAREST``, for the :py:meth:`~PIL.Image.Image.resize`
method and the :py:meth:`~PIL.ImageOps.pad``, :py:meth:`~PIL.ImageOps.scale``
and :py:meth:`~PIL.ImageOps.fit`` functions.
``Image.NEAREST`` is still always used for images in "P" and "1" modes.
See :ref:`concept-filters` to learn the difference. In short,
``Image.NEAREST`` is a very fast filter, but simple and low-quality.
Image.draft() return value
^^^^^^^^^^^^^^^^^^^^^^^^^^
The ``Image.draft()`` method used to return ``None`` or the image itself.
Unlike other `chain methods`_, ``draft()`` modifies the image in-place
rather than returning a modified version.
In the new version, ``draft()`` returns ``None`` if it has no effect or
a tuple of new image mode and the box of original coordinates in the
bounds of resulting image otherwise
(the box could be useful in subsequent ``resize()`` call).
.. _chain methods: https://en.wikipedia.org/wiki/Method_chaining
API Changes
===========
Deprecations
^^^^^^^^^^^^
TODO
~~~~
TODO
API Additions
=============
Custom unidentified image error
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Pillow will now throw a custom ``UnidentifiedImageError`` when an image cannot be
identified. For backwards compatibility, this will inherit from ``IOError``.
New argument ``reducing_gap`` for Image.resize() and Image.thumbnail() methods
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Speeds up resizing by resizing the image in two steps. The bigger ``reducing_gap``,
the closer the result to the fair resampling. The smaller ``reducing_gap``,
the faster resizing. With ``reducing_gap`` greater or equal to 3.0 result is
indistinguishable from fair resampling.
The default value for :py:meth:`~PIL.Image.Image.resize` is ``None``,
which means that the optimization is turned off by default.
The default value for :py:meth:`~PIL.Image.Image.thumbnail` is 2.0,
which is very close to fair resampling while still faster in many cases.
In addition, the same gap is applied when :py:meth:`~PIL.Image.Image.thumbnail`
calls :py:meth:`~PIL.Image.Image.draft`, which could greatly improve the quality
of JPEG thumbnails. As a result, :py:meth:`~PIL.Image.Image.thumbnail`
in the new version provides equally high speed and high quality from any
sources (JPEG or arbitrary images).
New Image.reduce() method
^^^^^^^^^^^^^^^^^^^^^^^^^
:py:meth:`~PIL.Image.Image.reduce` is a highly efficient operation
to reduce an image by integer times. Normally, shouldn't be used directly.
Used internally by :py:meth:`~PIL.Image.Image.resize` and :py:meth:`~PIL.Image.Image.thumbnail`
methods to speed up resize when a new argument ``reducing_gap`` is set.
Other Changes
=============
Image.__del__
^^^^^^^^^^^^^
Implicitly closing the image's underlying file in ``Image.__del__`` has been removed.
Use a context manager or call ``Image.close()`` instead to close the file in a
deterministic way.
Previous method:
.. code-block:: python
im = Image.open("hopper.png")
im.save("out.jpg")
Use instead:
.. code-block:: python
with Image.open("hopper.png") as im:
im.save("out.jpg")
Better thumbnail aspect ratio preservation
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
When calculating the new dimensions in ``Image.thumbnail``, round to the
nearest integer, instead of always rounding down.