PIL.GdImageFile 源代码

#
# The Python Imaging Library.
# $Id$
#
# GD file handling
#
# History:
# 1996-04-12 fl   Created
#
# Copyright (c) 1997 by Secret Labs AB.
# Copyright (c) 1996 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#


"""
.. note::
    This format cannot be automatically recognized, so the
    class is not registered for use with :py:func:`PIL.Image.open()`.  To open a
    gd file, use the :py:func:`PIL.GdImageFile.open()` function instead.

.. warning::
    THE GD FORMAT IS NOT DESIGNED FOR DATA INTERCHANGE.  This
    implementation is provided for convenience and demonstrational
    purposes only.
"""


from . import ImageFile, ImagePalette, UnidentifiedImageError
from ._binary import i16be as i16
from ._binary import i32be as i32


[文档] class GdImageFile(ImageFile.ImageFile): """ Image plugin for the GD uncompressed format. Note that this format is not supported by the standard :py:func:`PIL.Image.open()` function. To use this plugin, you have to import the :py:mod:`PIL.GdImageFile` module and use the :py:func:`PIL.GdImageFile.open()` function. """ format = "GD" format_description = "GD uncompressed images" def _open(self): # Header s = self.fp.read(1037) if i16(s) not in [65534, 65535]: msg = "Not a valid GD 2.x .gd file" raise SyntaxError(msg) self.mode = "L" # FIXME: "P" self._size = i16(s, 2), i16(s, 4) true_color = s[6] true_color_offset = 2 if true_color else 0 # transparency index tindex = i32(s, 7 + true_color_offset) if tindex < 256: self.info["transparency"] = tindex self.palette = ImagePalette.raw( "XBGR", s[7 + true_color_offset + 4 : 7 + true_color_offset + 4 + 256 * 4] ) self.tile = [ ( "raw", (0, 0) + self.size, 7 + true_color_offset + 4 + 256 * 4, ("L", 0, 1), ) ]
[文档] def open(fp, mode="r"): """ Load texture from a GD image file. :param fp: GD file name, or an opened file handle. :param mode: Optional mode. In this version, if the mode argument is given, it must be "r". :returns: An image instance. :raises OSError: If the image could not be read. """ if mode != "r": msg = "bad mode" raise ValueError(msg) try: return GdImageFile(fp) except SyntaxError as e: msg = "cannot identify this image file" raise UnidentifiedImageError(msg) from e