spectra/lib/python3.12/site-packages/PIL/FliImagePlugin.py
2024-11-05 13:55:44 -05:00

176 lines
4.6 KiB
Python

#
# The Python Imaging Library.
# $Id$
#
# FLI/FLC file handling.
#
# History:
# 95-09-01 fl Created
# 97-01-03 fl Fixed parser, setup decoder tile
# 98-07-15 fl Renamed offset attribute to avoid name clash
#
# Copyright (c) Secret Labs AB 1997-98.
# Copyright (c) Fredrik Lundh 1995-97.
#
# See the README file for information on usage and redistribution.
#
from __future__ import annotations
import os
from . import Image, ImageFile, ImagePalette
from ._binary import i16le as i16
from ._binary import i32le as i32
from ._binary import o8
#
# decoder
def _accept(prefix: bytes) -> bool:
return (
len(prefix) >= 6
and i16(prefix, 4) in [0xAF11, 0xAF12]
and i16(prefix, 14) in [0, 3] # flags
)
##
# Image plugin for the FLI/FLC animation format. Use the <b>seek</b>
# method to load individual frames.
class FliImageFile(ImageFile.ImageFile):
format = "FLI"
format_description = "Autodesk FLI/FLC Animation"
_close_exclusive_fp_after_loading = False
def _open(self) -> None:
# HEAD
s = self.fp.read(128)
if not (_accept(s) and s[20:22] == b"\x00\x00"):
msg = "not an FLI/FLC file"
raise SyntaxError(msg)
# frames
self.n_frames = i16(s, 6)
self.is_animated = self.n_frames > 1
# image characteristics
self._mode = "P"
self._size = i16(s, 8), i16(s, 10)
# animation speed
duration = i32(s, 16)
magic = i16(s, 4)
if magic == 0xAF11:
duration = (duration * 1000) // 70
self.info["duration"] = duration
# look for palette
palette = [(a, a, a) for a in range(256)]
s = self.fp.read(16)
self.__offset = 128
if i16(s, 4) == 0xF100:
# prefix chunk; ignore it
self.__offset = self.__offset + i32(s)
self.fp.seek(self.__offset)
s = self.fp.read(16)
if i16(s, 4) == 0xF1FA:
# look for palette chunk
number_of_subchunks = i16(s, 6)
chunk_size: int | None = None
for _ in range(number_of_subchunks):
if chunk_size is not None:
self.fp.seek(chunk_size - 6, os.SEEK_CUR)
s = self.fp.read(6)
chunk_type = i16(s, 4)
if chunk_type in (4, 11):
self._palette(palette, 2 if chunk_type == 11 else 0)
break
chunk_size = i32(s)
if not chunk_size:
break
self.palette = ImagePalette.raw(
"RGB", b"".join(o8(r) + o8(g) + o8(b) for (r, g, b) in palette)
)
# set things up to decode first frame
self.__frame = -1
self._fp = self.fp
self.__rewind = self.fp.tell()
self.seek(0)
def _palette(self, palette: list[tuple[int, int, int]], shift: int) -> None:
# load palette
i = 0
for e in range(i16(self.fp.read(2))):
s = self.fp.read(2)
i = i + s[0]
n = s[1]
if n == 0:
n = 256
s = self.fp.read(n * 3)
for n in range(0, len(s), 3):
r = s[n] << shift
g = s[n + 1] << shift
b = s[n + 2] << shift
palette[i] = (r, g, b)
i += 1
def seek(self, frame: int) -> None:
if not self._seek_check(frame):
return
if frame < self.__frame:
self._seek(0)
for f in range(self.__frame + 1, frame + 1):
self._seek(f)
def _seek(self, frame: int) -> None:
if frame == 0:
self.__frame = -1
self._fp.seek(self.__rewind)
self.__offset = 128
else:
# ensure that the previous frame was loaded
self.load()
if frame != self.__frame + 1:
msg = f"cannot seek to frame {frame}"
raise ValueError(msg)
self.__frame = frame
# move to next frame
self.fp = self._fp
self.fp.seek(self.__offset)
s = self.fp.read(4)
if not s:
msg = "missing frame size"
raise EOFError(msg)
framesize = i32(s)
self.decodermaxblock = framesize
self.tile = [ImageFile._Tile("fli", (0, 0) + self.size, self.__offset, None)]
self.__offset += framesize
def tell(self) -> int:
return self.__frame
#
# registry
Image.register_open(FliImageFile.format, FliImageFile, _accept)
Image.register_extensions(FliImageFile.format, [".fli", ".flc"])