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- #
- # The Python Imaging Library.
- # $Id$
- #
- # MPEG file handling
- #
- # History:
- # 95-09-09 fl Created
- #
- # Copyright (c) Secret Labs AB 1997.
- # Copyright (c) Fredrik Lundh 1995.
- #
- # See the README file for information on usage and redistribution.
- #
-
-
- from . import Image, ImageFile
- from ._binary import i8
-
- __version__ = "0.1"
-
-
- #
- # Bitstream parser
-
- class BitStream(object):
-
- def __init__(self, fp):
- self.fp = fp
- self.bits = 0
- self.bitbuffer = 0
-
- def next(self):
- return i8(self.fp.read(1))
-
- def peek(self, bits):
- while self.bits < bits:
- c = self.next()
- if c < 0:
- self.bits = 0
- continue
- self.bitbuffer = (self.bitbuffer << 8) + c
- self.bits += 8
- return self.bitbuffer >> (self.bits - bits) & (1 << bits) - 1
-
- def skip(self, bits):
- while self.bits < bits:
- self.bitbuffer = (self.bitbuffer << 8) + i8(self.fp.read(1))
- self.bits += 8
- self.bits = self.bits - bits
-
- def read(self, bits):
- v = self.peek(bits)
- self.bits = self.bits - bits
- return v
-
-
- ##
- # Image plugin for MPEG streams. This plugin can identify a stream,
- # but it cannot read it.
-
- class MpegImageFile(ImageFile.ImageFile):
-
- format = "MPEG"
- format_description = "MPEG"
-
- def _open(self):
-
- s = BitStream(self.fp)
-
- if s.read(32) != 0x1B3:
- raise SyntaxError("not an MPEG file")
-
- self.mode = "RGB"
- self._size = s.read(12), s.read(12)
-
-
- # --------------------------------------------------------------------
- # Registry stuff
-
- Image.register_open(MpegImageFile.format, MpegImageFile)
-
- Image.register_extensions(MpegImageFile.format, [".mpg", ".mpeg"])
-
- Image.register_mime(MpegImageFile.format, "video/mpeg")
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