PIL.FliImagePlugin 源代码

#
# 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 PIL import Image, ImageFile, ImagePalette, _binary

__version__ = "0.2"

i8 = _binary.i8
i16 = _binary.i16le
i32 = _binary.i32le
o8 = _binary.o8


#
# decoder

def _accept(prefix):
    return len(prefix) >= 6 and i16(prefix[4:6]) in [0xAF11, 0xAF12]


##
# Image plugin for the FLI/FLC animation format.  Use the <b>seek</b>
# method to load individual frames.

[文档]class FliImageFile(ImageFile.ImageFile): format = "FLI" format_description = "Autodesk FLI/FLC Animation" def _open(self): # HEAD s = self.fp.read(128) magic = i16(s[4:6]) if not (magic in [0xAF11, 0xAF12] and i16(s[14:16]) in [0, 3] and # flags s[20:22] == b"\x00\x00"): # reserved raise SyntaxError("not an FLI/FLC file") # image characteristics self.mode = "P" self.size = i16(s[8:10]), i16(s[10:12]) # animation speed duration = i32(s[16:20]) 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[4:6]) == 0xF100: # prefix chunk; ignore it self.__offset = self.__offset + i32(s) s = self.fp.read(16) if i16(s[4:6]) == 0xF1FA: # look for palette chunk s = self.fp.read(6) if i16(s[4:6]) == 11: self._palette(palette, 2) elif i16(s[4:6]) == 4: self._palette(palette, 0) palette = [o8(r)+o8(g)+o8(b) for (r, g, b) in palette] self.palette = ImagePalette.raw("RGB", b"".join(palette)) # set things up to decode first frame self.__frame = -1 self.__fp = self.fp self.__rewind = self.fp.tell() self._n_frames = None self._is_animated = None self.seek(0) def _palette(self, palette, shift): # load palette i = 0 for e in range(i16(self.fp.read(2))): s = self.fp.read(2) i = i + i8(s[0]) n = i8(s[1]) if n == 0: n = 256 s = self.fp.read(n * 3) for n in range(0, len(s), 3): r = i8(s[n]) << shift g = i8(s[n+1]) << shift b = i8(s[n+2]) << shift palette[i] = (r, g, b) i += 1 @property def n_frames(self): if self._n_frames is None: current = self.tell() try: while True: self.seek(self.tell() + 1) except EOFError: self._n_frames = self.tell() + 1 self.seek(current) return self._n_frames @property def is_animated(self): if self._is_animated is None: current = self.tell() try: self.seek(1) self._is_animated = True except EOFError: self._is_animated = False self.seek(current) return self._is_animated
[文档] def seek(self, frame): if frame == self.__frame: return if frame < self.__frame: self._seek(0) last_frame = self.__frame for f in range(self.__frame + 1, frame + 1): try: self._seek(f) except EOFError: self.seek(last_frame) raise EOFError("no more images in FLI file")
def _seek(self, frame): if frame == 0: self.__frame = -1 self.__fp.seek(self.__rewind) self.__offset = 128 if frame != self.__frame + 1: raise ValueError("cannot seek to frame %d" % frame) self.__frame = frame # move to next frame self.fp = self.__fp self.fp.seek(self.__offset) s = self.fp.read(4) if not s: raise EOFError framesize = i32(s) self.decodermaxblock = framesize self.tile = [("fli", (0, 0)+self.size, self.__offset, None)] self.__offset += framesize
[文档] def tell(self): return self.__frame
# # registry Image.register_open(FliImageFile.format, FliImageFile, _accept) Image.register_extension(FliImageFile.format, ".fli") Image.register_extension(FliImageFile.format, ".flc")