codekingpro/portable-devtools

1#
2# The Python Imaging Library.
3# $Id$
4#
5# FLI/FLC file handling.
6#
7# History:
8#       95-09-01 fl     Created
9#       97-01-03 fl     Fixed parser, setup decoder tile
10#       98-07-15 fl     Renamed offset attribute to avoid name clash
11#
12# Copyright (c) Secret Labs AB 1997-98.
13# Copyright (c) Fredrik Lundh 1995-97.
14#
15# See the README file for information on usage and redistribution.
16#
17from __future__ import annotations
18
19import os
20
21from . import Image, ImageFile, ImagePalette
22from ._binary import i16le as i16
23from ._binary import i32le as i32
24from ._binary import o8
25from ._util import DeferredError
26
27#
28# decoder
29
30
31def _accept(prefix: bytes) -> bool:
32    return (
33        len(prefix) >= 16
34        and i16(prefix, 4) in [0xAF11, 0xAF12]
35        and i16(prefix, 14) in [0, 3]  # flags
36    )
37
38
39##
40# Image plugin for the FLI/FLC animation format.  Use the <b>seek</b>
41# method to load individual frames.
42
43
44class FliImageFile(ImageFile.ImageFile):
45    format = "FLI"
46    format_description = "Autodesk FLI/FLC Animation"
47    _close_exclusive_fp_after_loading = False
48
49    def _open(self) -> None:
50        # HEAD
51        assert self.fp is not None
52        s = self.fp.read(128)
53        if not (
54            _accept(s)
55            and s[20:22] == b"\x00" * 2
56            and s[42:80] == b"\x00" * 38
57            and s[88:] == b"\x00" * 40
58        ):
59            msg = "not an FLI/FLC file"
60            raise SyntaxError(msg)
61
62        # frames
63        self.n_frames = i16(s, 6)
64        self.is_animated = self.n_frames > 1
65
66        # image characteristics
67        self._mode = "P"
68        self._size = i16(s, 8), i16(s, 10)
69
70        # animation speed
71        duration = i32(s, 16)
72        magic = i16(s, 4)
73        if magic == 0xAF11:
74            duration = (duration * 1000) // 70
75        self.info["duration"] = duration
76
77        # look for palette
78        palette = [(a, a, a) for a in range(256)]
79
80        s = self.fp.read(16)
81
82        self.__offset = 128
83
84        if i16(s, 4) == 0xF100:
85            # prefix chunk; ignore it
86            self.fp.seek(self.__offset + i32(s))
87            s = self.fp.read(16)
88
89        if i16(s, 4) == 0xF1FA:
90            # look for palette chunk
91            number_of_subchunks = i16(s, 6)
92            chunk_size: int | None = None
93            for _ in range(number_of_subchunks):
94                if chunk_size is not None:
95                    self.fp.seek(chunk_size - 6, os.SEEK_CUR)
96                s = self.fp.read(6)
97                chunk_type = i16(s, 4)
98                if chunk_type in (4, 11):
99                    self._palette(palette, 2 if chunk_type == 11 else 0)
100                    break
101                chunk_size = i32(s)
102                if not chunk_size:
103                    break
104
105        self.palette = ImagePalette.raw(
106            "RGB", b"".join(o8(r) + o8(g) + o8(b) for (r, g, b) in palette)
107        )
108
109        # set things up to decode first frame
110        self.__frame = -1
111        self._fp = self.fp
112        self.__rewind = self.fp.tell()
113        self.seek(0)
114
115    def _palette(self, palette: list[tuple[int, int, int]], shift: int) -> None:
116        # load palette
117
118        i = 0
119        assert self.fp is not None
120        for e in range(i16(self.fp.read(2))):
121            s = self.fp.read(2)
122            i = i + s[0]
123            n = s[1]
124            if n == 0:
125                n = 256
126            s = self.fp.read(n * 3)
127            for n in range(0, len(s), 3):
128                r = s[n] << shift
129                g = s[n + 1] << shift
130                b = s[n + 2] << shift
131                palette[i] = (r, g, b)
132                i += 1
133
134    def seek(self, frame: int) -> None:
135        if not self._seek_check(frame):
136            return
137        if frame < self.__frame:
138            self._seek(0)
139
140        for f in range(self.__frame + 1, frame + 1):
141            self._seek(f)
142
143    def _seek(self, frame: int) -> None:
144        if isinstance(self._fp, DeferredError):
145            raise self._fp.ex
146        if frame == 0:
147            self.__frame = -1
148            self._fp.seek(self.__rewind)
149            self.__offset = 128
150        else:
151            # ensure that the previous frame was loaded
152            self.load()
153
154        if frame != self.__frame + 1:
155            msg = f"cannot seek to frame {frame}"
156            raise ValueError(msg)
157        self.__frame = frame
158
159        # move to next frame
160        self.fp = self._fp
161        self.fp.seek(self.__offset)
162
163        s = self.fp.read(4)
164        if not s:
165            msg = "missing frame size"
166            raise EOFError(msg)
167
168        framesize = i32(s)
169
170        self.decodermaxblock = framesize
171        self.tile = [ImageFile._Tile("fli", (0, 0) + self.size, self.__offset)]
172
173        self.__offset += framesize
174
175    def tell(self) -> int:
176        return self.__frame
177
178
179#
180# registry
181
182Image.register_open(FliImageFile.format, FliImageFile, _accept)
183
184Image.register_extensions(FliImageFile.format, [".fli", ".flc"])
185