Aluode/PerceptionLabPortable

1#
2# The Python Imaging Library.
3# $Id$
4#
5# XPM File handling
6#
7# History:
8# 1996-12-29 fl   Created
9# 2001-02-17 fl   Use 're' instead of 'regex' (Python 2.1) (0.7)
10#
11# Copyright (c) Secret Labs AB 1997-2001.
12# Copyright (c) Fredrik Lundh 1996-2001.
13#
14# See the README file for information on usage and redistribution.
15#
16from __future__ import annotations
17
18import re
19
20from . import Image, ImageFile, ImagePalette
21from ._binary import o8
22
23# XPM header
24xpm_head = re.compile(b'"([0-9]*) ([0-9]*) ([0-9]*) ([0-9]*)')
25
26
27def _accept(prefix: bytes) -> bool:
28    return prefix.startswith(b"/* XPM */")
29
30
31##
32# Image plugin for X11 pixel maps.
33
34
35class XpmImageFile(ImageFile.ImageFile):
36    format = "XPM"
37    format_description = "X11 Pixel Map"
38
39    def _open(self) -> None:
40        assert self.fp is not None
41        if not _accept(self.fp.read(9)):
42            msg = "not an XPM file"
43            raise SyntaxError(msg)
44
45        # skip forward to next string
46        while True:
47            line = self.fp.readline()
48            if not line:
49                msg = "broken XPM file"
50                raise SyntaxError(msg)
51            m = xpm_head.match(line)
52            if m:
53                break
54
55        self._size = int(m.group(1)), int(m.group(2))
56
57        palette_length = int(m.group(3))
58        bpp = int(m.group(4))
59
60        #
61        # load palette description
62
63        palette = {}
64
65        for _ in range(palette_length):
66            line = self.fp.readline().rstrip()
67
68            c = line[1 : bpp + 1]
69            s = line[bpp + 1 : -2].split()
70
71            for i in range(0, len(s), 2):
72                if s[i] == b"c":
73                    # process colour key
74                    rgb = s[i + 1]
75                    if rgb == b"None":
76                        self.info["transparency"] = c
77                    elif rgb.startswith(b"#"):
78                        rgb_int = int(rgb[1:], 16)
79                        palette[c] = (
80                            o8((rgb_int >> 16) & 255)
81                            + o8((rgb_int >> 8) & 255)
82                            + o8(rgb_int & 255)
83                        )
84                    else:
85                        # unknown colour
86                        msg = "cannot read this XPM file"
87                        raise ValueError(msg)
88                    break
89
90            else:
91                # missing colour key
92                msg = "cannot read this XPM file"
93                raise ValueError(msg)
94
95        args: tuple[int, dict[bytes, bytes] | tuple[bytes, ...]]
96        if palette_length > 256:
97            self._mode = "RGB"
98            args = (bpp, palette)
99        else:
100            self._mode = "P"
101            self.palette = ImagePalette.raw("RGB", b"".join(palette.values()))
102            args = (bpp, tuple(palette.keys()))
103
104        self.tile = [ImageFile._Tile("xpm", (0, 0) + self.size, self.fp.tell(), args)]
105
106    def load_read(self, read_bytes: int) -> bytes:
107        #
108        # load all image data in one chunk
109
110        xsize, ysize = self.size
111
112        assert self.fp is not None
113        s = [self.fp.readline()[1 : xsize + 1].ljust(xsize) for i in range(ysize)]
114
115        return b"".join(s)
116
117
118class XpmDecoder(ImageFile.PyDecoder):
119    _pulls_fd = True
120
121    def decode(self, buffer: bytes | Image.SupportsArrayInterface) -> tuple[int, int]:
122        assert self.fd is not None
123
124        data = bytearray()
125        bpp, palette = self.args
126        dest_length = self.state.xsize * self.state.ysize
127        if self.mode == "RGB":
128            dest_length *= 3
129        pixel_header = False
130        while len(data) < dest_length:
131            line = self.fd.readline()
132            if not line:
133                break
134            if line.rstrip() == b"/* pixels */" and not pixel_header:
135                pixel_header = True
136                continue
137            line = b'"'.join(line.split(b'"')[1:-1])
138            for i in range(0, len(line), bpp):
139                key = line[i : i + bpp]
140                if self.mode == "RGB":
141                    data += palette[key]
142                else:
143                    data += o8(palette.index(key))
144        self.set_as_raw(bytes(data))
145        return -1, 0
146
147
148#
149# Registry
150
151
152Image.register_open(XpmImageFile.format, XpmImageFile, _accept)
153Image.register_decoder("xpm", XpmDecoder)
154
155Image.register_extension(XpmImageFile.format, ".xpm")
156
157Image.register_mime(XpmImageFile.format, "image/xpm")
158