Aluode/PerceptionLabPortable

1#
2# The Python Imaging Library.
3# $Id$
4#
5# GD file handling
6#
7# History:
8# 1996-04-12 fl   Created
9#
10# Copyright (c) 1997 by Secret Labs AB.
11# Copyright (c) 1996 by Fredrik Lundh.
12#
13# See the README file for information on usage and redistribution.
14#
15
16
17"""
18.. note::
19    This format cannot be automatically recognized, so the
20    class is not registered for use with :py:func:`PIL.Image.open()`.  To open a
21    gd file, use the :py:func:`PIL.GdImageFile.open()` function instead.
22
23.. warning::
24    THE GD FORMAT IS NOT DESIGNED FOR DATA INTERCHANGE.  This
25    implementation is provided for convenience and demonstrational
26    purposes only.
27"""
28from __future__ import annotations
29
30from typing import IO
31
32from . import ImageFile, ImagePalette, UnidentifiedImageError
33from ._binary import i16be as i16
34from ._binary import i32be as i32
35from ._typing import StrOrBytesPath
36
37
38class GdImageFile(ImageFile.ImageFile):
39    """
40    Image plugin for the GD uncompressed format.  Note that this format
41    is not supported by the standard :py:func:`PIL.Image.open()` function.  To use
42    this plugin, you have to import the :py:mod:`PIL.GdImageFile` module and
43    use the :py:func:`PIL.GdImageFile.open()` function.
44    """
45
46    format = "GD"
47    format_description = "GD uncompressed images"
48
49    def _open(self) -> None:
50        # Header
51        assert self.fp is not None
52
53        s = self.fp.read(1037)
54
55        if i16(s) not in [65534, 65535]:
56            msg = "Not a valid GD 2.x .gd file"
57            raise SyntaxError(msg)
58
59        self._mode = "P"
60        self._size = i16(s, 2), i16(s, 4)
61
62        true_color = s[6]
63        true_color_offset = 2 if true_color else 0
64
65        # transparency index
66        tindex = i32(s, 7 + true_color_offset)
67        if tindex < 256:
68            self.info["transparency"] = tindex
69
70        self.palette = ImagePalette.raw(
71            "RGBX", s[7 + true_color_offset + 6 : 7 + true_color_offset + 6 + 256 * 4]
72        )
73
74        self.tile = [
75            ImageFile._Tile(
76                "raw",
77                (0, 0) + self.size,
78                7 + true_color_offset + 6 + 256 * 4,
79                "L",
80            )
81        ]
82
83
84def open(fp: StrOrBytesPath | IO[bytes], mode: str = "r") -> GdImageFile:
85    """
86    Load texture from a GD image file.
87
88    :param fp: GD file name, or an opened file handle.
89    :param mode: Optional mode.  In this version, if the mode argument
90        is given, it must be "r".
91    :returns: An image instance.
92    :raises OSError: If the image could not be read.
93    """
94    if mode != "r":
95        msg = "bad mode"
96        raise ValueError(msg)
97
98    try:
99        return GdImageFile(fp)
100    except SyntaxError as e:
101        msg = "cannot identify this image file"
102        raise UnidentifiedImageError(msg) from e
103