Aluode/PerceptionLabPortable

1#
2# Python Imaging Library
3# $Id$
4#
5# stuff to read GIMP palette files
6#
7# History:
8# 1997-08-23 fl     Created
9# 2004-09-07 fl     Support GIMP 2.0 palette files.
10#
11# Copyright (c) Secret Labs AB 1997-2004.  All rights reserved.
12# Copyright (c) Fredrik Lundh 1997-2004.
13#
14# See the README file for information on usage and redistribution.
15#
16from __future__ import annotations
17
18import re
19from io import BytesIO
20
21TYPE_CHECKING = False
22if TYPE_CHECKING:
23    from typing import IO
24
25
26class GimpPaletteFile:
27    """File handler for GIMP's palette format."""
28
29    rawmode = "RGB"
30
31    def _read(self, fp: IO[bytes], limit: bool = True) -> None:
32        if not fp.readline().startswith(b"GIMP Palette"):
33            msg = "not a GIMP palette file"
34            raise SyntaxError(msg)
35
36        palette: list[int] = []
37        i = 0
38        while True:
39            if limit and i == 256 + 3:
40                break
41
42            i += 1
43            s = fp.readline()
44            if not s:
45                break
46
47            # skip fields and comment lines
48            if re.match(rb"\w+:|#", s):
49                continue
50            if limit and len(s) > 100:
51                msg = "bad palette file"
52                raise SyntaxError(msg)
53
54            v = s.split(maxsplit=3)
55            if len(v) < 3:
56                msg = "bad palette entry"
57                raise ValueError(msg)
58
59            palette += (int(v[i]) for i in range(3))
60            if limit and len(palette) == 768:
61                break
62
63        self.palette = bytes(palette)
64
65    def __init__(self, fp: IO[bytes]) -> None:
66        self._read(fp)
67
68    @classmethod
69    def frombytes(cls, data: bytes) -> GimpPaletteFile:
70        self = cls.__new__(cls)
71        self._read(BytesIO(data), False)
72        return self
73
74    def getpalette(self) -> tuple[bytes, str]:
75        return self.palette, self.rawmode
76