#
# 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 Image.open(). To open a
# gd file, use the GdImageFile.open() function instead.
# THE GD FORMAT IS NOT DESIGNED FOR DATA INTERCHANGE. This
# implementation is provided for convenience and demonstrational
# purposes only.
from . import ImageFile, ImagePalette
from ._binary import i8, i16be as i16, i32be as i32
__version__ = "0.1"
##
# Image plugin for the GD uncompressed format. Note that this format
# is not supported by the standard <b>Image.open</b> function. To use
# this plugin, you have to import the <b>GdImageFile</b> module and
# use the <b>GdImageFile.open</b> function.
[文档]class GdImageFile(ImageFile.ImageFile):
format = "GD"
format_description = "GD uncompressed images"
def _open(self):
# Header
s = self.fp.read(1037)
if not i16(s[:2]) in [65534, 65535]:
raise SyntaxError("Not a valid GD 2.x .gd file")
self.mode = "L" # FIXME: "P"
self._size = i16(s[2:4]), i16(s[4:6])
trueColor = i8(s[6])
trueColorOffset = 2 if trueColor else 0
# transparency index
tindex = i32(s[7+trueColorOffset:7+trueColorOffset+4])
if tindex < 256:
self.info["transparency"] = tindex
self.palette = ImagePalette.raw(
"XBGR", s[7+trueColorOffset+4:7+trueColorOffset+4+256*4])
self.tile = [("raw", (0, 0)+self.size, 7+trueColorOffset+4+256*4,
("L", 0, 1))]
[文档]def open(fp, mode="r"):
"""
Load texture from a GD image file.
:param filename: 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 IOError: If the image could not be read.
"""
if mode != "r":
raise ValueError("bad mode")
try:
return GdImageFile(fp)
except SyntaxError:
raise IOError("cannot identify this image file")