Pillow/docs/releasenotes/5.4.0.rst

5.4.0
-----

API Changes
===========

APNG extension to PNG plugin
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Animated Portable Network Graphics (APNG) images are not fully supported but
can be opened via the PNG plugin to get some basic info::

    im = Image.open("image.apng")
    print(im.mode)  # "RGBA"
    print(im.size)  # (245, 245)
    im.show()  # Shows a single frame

Check for libjpeg-turbo
^^^^^^^^^^^^^^^^^^^^^^^

You can check if Pillow has been built against the libjpeg-turbo version of the
libjpeg library::

    from PIL import features
    features.check_feature("libjpeg_turbo")  # True or False

Negative indexes in pixel access
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

When accessing individual image pixels, negative indexes are now also accepted.
For example, to get or set the farthest pixel in the lower right of an image::

    px = im.load()
    print(px[-1, -1])
    px[-1, -1] = (0, 0, 0)


New custom TIFF tags
^^^^^^^^^^^^^^^^^^^^

TIFF images can now be saved with custom integer, float and string TIFF tags::

    im = Image.new("RGB", (200, 100))
    custom = {
        37000: 4,
        37001: 4.2,
        37002: "custom tag value",
        37003: u"custom tag value",
        37004: b"custom tag value",
    }
    im.save("output.tif", tiffinfo=custom)

    im2 = Image.open("output.tif")
    print(im2.tag_v2[37000])  # 4
    print(im2.tag_v2[37002])  # "custom tag value"
    print(im2.tag_v2[37004])  # b"custom tag value"

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

ImageOps.fit
^^^^^^^^^^^^

Now uses one resize operation with ``box`` parameter internally
instead of a crop and scale operations sequence.
This improves the performance and accuracy of cropping since
the ``box`` parameter accepts float values.