4.2.0
-----

Backwards Incompatible Changes
==============================

Several deprecated items have been removed
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

* The methods ``PIL.ImageWin.Dib.fromstring``,
  ``PIL.ImageWin.Dib.tostring`` and
  ``PIL.TiffImagePlugin.ImageFileDirectory_v2.as_dict`` have
  been removed.

* Before Pillow 4.2.0, attempting to save an RGBA image as JPEG would
  discard the alpha channel. From Pillow 3.4.0, a deprecation warning
  was shown. From Pillow 4.2.0, the deprecation warning is removed and
  an :py:exc:`IOError` is raised.

Removed Core Image Function
^^^^^^^^^^^^^^^^^^^^^^^^^^^

The unused function ``Image.core.new_array`` was removed. This is an
internal function that should not have been used by user code, but it
was accessible from the python layer.

Other Changes
=============

Added Complex Text Rendering
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Pillow now supports complex text rendering for scripts requiring glyph
composition and bidirectional flow. This optional feature adds three
dependencies: harfbuzz, fribidi, and raqm. See the :doc:`install documentation
<../installation>` for further details. This feature is tested and works on
Unix and Mac, but has not yet been built on Windows platforms.

New Optional Parameters
^^^^^^^^^^^^^^^^^^^^^^^

* :py:meth:`PIL.ImageDraw.floodfill` has a new optional parameter:
  threshold. This specifies a tolerance for the color to replace with
  the flood fill.

* The TIFF and PDF image writers now support the ``append_images``
  optional parameter for specifying additional images to create
  multipage outputs.

New DecompressionBomb Warning
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

:py:meth:`PIL.Image.Image.crop` now may raise a DecompressionBomb
warning if the crop region enlarges the image over the threshold
specified by :py:data:`PIL.Image.MAX_IMAGE_PIXELS`.
