varia.website/venv/lib/python3.11/site-packages/PIL/GdImageFile.py
2024-11-19 14:01:39 +01:00

91 lines
2.4 KiB
Python

#
# 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
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 not i16(s) in [65534, 65535]:
raise SyntaxError("Not a valid GD 2.x .gd file")
self.mode = "L" # FIXME: "P"
self._size = i16(s, 2), i16(s, 4)
trueColor = s[6]
trueColorOffset = 2 if trueColor else 0
# transparency index
tindex = i32(s, 7 + trueColorOffset)
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))
]
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 OSError: If the image could not be read.
"""
if mode != "r":
raise ValueError("bad mode")
try:
return GdImageFile(fp)
except SyntaxError as e:
raise UnidentifiedImageError("cannot identify this image file") from e