Pillow/docs/releasenotes/9.4.0.rst

9.4.0
-----

Security
========

Fix memory DOS in ImageFont
^^^^^^^^^^^^^^^^^^^^^^^^^^^

A corrupt or specially crafted TTF font could have font metrics that lead to
unreasonably large sizes when rendering text in font. ``ImageFont.py`` did not
check the image size before allocating memory for it. This dates to the PIL
fork. Pillow 8.2.0 added a check for large sizes, but did not consider the
case where one dimension is zero.

Null pointer dereference crash in ImageFont
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Pillow attempted to dereference a null pointer in ``ImageFont``, leading to a
crash. An error is now raised instead. This has been present since
Pillow 8.0.0.

API Additions
=============

Added start position for getmask and getmask2
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Text may render differently when starting at fractional coordinates, so
:py:meth:`.FreeTypeFont.getmask` and :py:meth:`.FreeTypeFont.getmask2` now
support a ``start`` argument. This tuple of horizontal and vertical offset
will be used internally by :py:meth:`.ImageDraw.text` to more accurately place
text at the ``xy`` coordinates.

Added the ``exact`` encoding option for WebP
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The ``exact`` encoding option for WebP is now supported. The WebP encoder
removes the hidden RGB values for better compression by default in libwebp 0.5
or later. By setting this option to ``True``, the encoder will keep the hidden
RGB values.

Added ``signed`` option when saving JPEG2000
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

If the ``signed`` keyword argument is present and true when saving JPEG2000
images, then tell the encoder to save the image as signed.

Added IFD, Interop and LightSource ExifTags enums
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

:py:data:`~PIL.ExifTags.IFD` has been added, allowing enums to be used with
:py:meth:`~PIL.Image.Exif.get_ifd`::

    from PIL import Image, ExifTags
    im = Image.open("Tests/images/flower.jpg")
    print(im.getexif().get_ifd(ExifTags.IFD.Exif))

``IFD1`` can also be used with :py:meth:`~PIL.Image.Exif.get_ifd`, but it should
not be used in other contexts, as the enum value is only internally meaningful.

:py:data:`~PIL.ExifTags.Interop` has been added for tags within the Interop IFD::

    from PIL import Image, ExifTags
    im = Image.open("Tests/images/flower.jpg")
    interop_ifd = im.getexif().get_ifd(ExifTags.IFD.Interop)
    print(interop_ifd.get(ExifTags.Interop.InteropIndex))  # R98

:py:data:`~PIL.ExifTags.LightSource` has been added for values within the LightSource
tag::

    from PIL import Image, ExifTags
    im = Image.open("Tests/images/iptc.jpg")
    exif_ifd = im.getexif().get_ifd(ExifTags.IFD.Exif)
    print(ExifTags.LightSource(exif_ifd[0x9208]))  # LightSource.Unknown

getxmp()
^^^^^^^^

`XMP data <https://en.wikipedia.org/wiki/Extensible_Metadata_Platform>`_ can now be
decoded for WEBP images through ``getxmp()``.

Writing JPEG comments
^^^^^^^^^^^^^^^^^^^^^

When saving a JPEG image, a comment can now be written from
:py:attr:`~PIL.Image.Image.info`, or by using an argument when saving::

    im.save(out, comment="Test comment")

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

Added support for DDS L and LA images
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Support has been added to read and write L and LA DDS images in the uncompressed
format, known as "luminance" textures.

.. _restored-image-constants:

Constants
^^^^^^^^^

In Pillow 9.1.0, the following constants were deprecated. That has been reversed and
these constants will now remain available.

- ``Image.NONE``
- ``Image.NEAREST``
- ``Image.ORDERED``
- ``Image.RASTERIZE``
- ``Image.FLOYDSTEINBERG``
- ``Image.WEB``
- ``Image.ADAPTIVE``
- ``Image.AFFINE``
- ``Image.EXTENT``
- ``Image.PERSPECTIVE``
- ``Image.QUAD``
- ``Image.MESH``
- ``Image.FLIP_LEFT_RIGHT``
- ``Image.FLIP_TOP_BOTTOM``
- ``Image.ROTATE_90``
- ``Image.ROTATE_180``
- ``Image.ROTATE_270``
- ``Image.TRANSPOSE``
- ``Image.TRANSVERSE``
- ``Image.BOX``
- ``Image.BILINEAR``
- ``Image.HAMMING``
- ``Image.BICUBIC``
- ``Image.LANCZOS``
- ``Image.MEDIANCUT``
- ``Image.MAXCOVERAGE``
- ``Image.FASTOCTREE``
- ``Image.LIBIMAGEQUANT``