python-pillow/Pillow
1
1
Fork 0
mirror of https://github.com/python-pillow/Pillow.git synced 2025-01-13 18:56:17 +03:00
Code Issues Packages Projects Releases Wiki Activity

extend documentation for PNG transparency

Browse Source
This commit is contained in:
Oliver Tonnhofer 2016-04-19 10:21:19 +02:00
parent c773688f37
commit eb0f400e02
1 changed files with 10 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
docs/handbook/image-file-formats.rst
View File

@ -370,8 +370,13 @@ The :py:meth:`~PIL.Image.Image.open` method sets the following
Gamma, given as a floating point number.
**transparency**
Transparency color index. This key is omitted if the image is not a
transparent palette image.
For ``P`` images: Either the palette index for full transparent pixels,
or a byte string with alpha values for each palette entry.
For ``L`` and ``RGB`` images, the color that represents full transparent
pixels in this image.
This key is omitted if the image is not a transparent palette image.
``Open`` also sets ``Image.text`` to a list of the values of the
``tEXt``, ``zTXt``, and ``iTXt`` chunks of the PNG image. Individual
@ -392,6 +397,9 @@ The :py:meth:`~PIL.Image.Image.save` method supports the following options:
For ``P``, ``L``, and ``RGB`` images, this option controls what
color image to mark as transparent.
For ``P`` images, this can be a either the palette index,
or a byte string with alpha values for each palette entry.
**dpi**
A tuple of two numbers corresponding to the desired dpi in each direction.